feat(calendar): abonnement på flere kalendere, ICS og webcal

Bedt om som "abonnering af flere kalendere (ics og webcal?)". Det er også den
eneste vej for en privat konto: instansens OAuth-klient er Internal, og Google
afviser en konto udefra med `org_internal`, uanset hvad der ellers er sat op.

**Samme tabeller.** Et abonnement er én kalender med begivenheder i, og det er
præcis det, `calendars` og `calendar_events` allerede beskriver — med vinduet,
farven, `shown` og hele fejemaskinen omkring sig. En tabel til ville være en anden
vej til det samme sted, og to veje til ét sted er to steder at rette den dag noget
om begivenheder ændrer sig.

Det, der skulle laves om, var identiteten. En OAuth-konto er én pr. person og
udbyder — tokenet er identiteten — mens et abonnement er én pr. adresse, og man har
flere. `calendar_accounts_once` er derfor delvist nu: det holder for rækkerne uden
adresse, og et andet indeks holder adresserne unikke. Delvise indekser er den ene
ting, SQLite kan her, som ellers krævede en tabelombygning.

**`webcal://` skrives om til `https://`.** Det er ikke en protokol, noget taler —
det er en konvention, der får et skrivebord til at give adressen til
kalenderprogrammet i stedet for til browseren, og alle udgivere skriver deres links
sådan. At afvise den ville være at afvise folk på en teknikalitet.

**Adressen gennem `safedial`, begge halvdele.** Afvist hvor den skrives ned, så
den, der står med feltet, får svaret med det samme — og igen på den *opslåede*
adresse hver gang den hentes, fordi et navn, der blev godkendt ved indtastningen,
kan svare 127.0.0.1, når fejemaskinen kører klokken tre om natten. Det er den
sætning, `internal/safedial` selv står og advarer om, og den blev skrevet efter et
SSRF-fund i morges.

**Hentet én gang, før den gemmes.** En adresse, der ikke kan læses, er en tastefejl
langt oftere end en server, der tilfældigvis er nede, og at sige det, mens nogen
står med feltet, er de to sekunder værd. Et abonnement, der lydløst aldrig fyldes,
er den samme tavshed, notifikationerne havde.

Læseren er ny i `internal/ics`, som hidtil kun kunne skrive. To ting, den med vilje
ikke gør, står skrevet ved den: den udfolder ikke gentagelser, og den opløser ikke
tidszoner. Begge dele er større end de ser ud, og begge har ét sted at høre til
den dag de skal.

En ting, formatet lærte: DTEND er eksklusiv for en heldagsbegivenhed. Gemmes den,
som filen skriver den, dækker hver eneste helligdag også dagen efter sig.

Én adresse, der fejler, stopper ikke de andre. Et abonnement er en anden persons
server, og den ordinære tilstand for en anden persons server er, at den er i orden
indtil en morgen hvor den ikke er.

Co-Authored-By: Claude Opus 5 <[email protected]>

.gitignore

@@ -66,3 +66,6 @@ node_modules.nosync/
 # Kept on disk because it is how a session hands over to the next one.
 HANDOFF.md
 NOTES-PLAN.md
+
+# Agenternes arbejdstræer. Et git-repo inde i et git-repo, som ikke hører til her.
+.claude/worktrees/

NOTES-SPEC.md

@@ -0,0 +1,437 @@
+# Notes, as verdande builds them
+
+A description of one working notes system: the data model, the syntax, the search,
+the rendering contract, the import and export formats, and — more useful than any
+of it — the decisions that look arbitrary until you know what they cost.
+
+It is written to be lifted into another program. Nothing here depends on Go,
+SQLite or Svelte except where it says so; where an answer was forced by the tool,
+that is called out so you can pick a different one on purpose rather than by
+accident.
+
+---
+
+## Read this part first: what to ask before you build
+
+**This document is not a drop-in. It describes a notes system that lives inside a
+task app with projects, roles, a trash and a search box, and about a third of its
+design is inherited from that.** Lifting it into a program with different
+surroundings without deciding which parts to keep produces something that works
+for a week and then fights you.
+
+**If you are an assistant working from this file: ask these questions and get
+answers before writing code.** Do not guess a default. Each one changes what you
+build, not just how you build it.
+
+### About the surroundings
+
+1. **Does the host app already have a place to file things** — projects, folders,
+   notebooks, tags? verdande deliberately gave notes no hierarchy of their own and
+   filed them under the projects that already existed. If your app has nothing,
+   you need an answer for where a note lives, and "a folder tree" is the expensive
+   one.
+2. **Is there more than one person?** Sharing, roles and "who wrote this" run
+   through the whole model below. Single-user changes the schema and removes about
+   half the permission surface.
+3. **Is there already a trash, and does it expire?** Notes lean on one. Without
+   it, deleting is either permanent or you are building a trash.
+4. **Is there an existing full-text index?** The search here is FTS5-shaped. On
+   Postgres it is `tsvector`, on a client-side app it is probably a scan, and the
+   ranking section below changes accordingly.
+
+### About the notes themselves
+
+5. **Markdown, rich text, or blocks?** verdande stores Markdown and renders it.
+   That decision is defended below; it is also the one that most constrains
+   everything else.
+6. **Is the first line the title, or is there a title field?** Both work. Deriving
+   it means one less thing to keep in step and one less thing a person can leave
+   blank, and it forces the rule "the first line is a heading" on the editor.
+7. **What links to what?** `#project`, `[[note]]` and task references exist here
+   because the app has projects and tasks. Yours may have none of them, or others.
+8. **Do notes carry files?** Attachments bring content-type handling, a store, an
+   authorisation path and an XSS surface. Skipping them is a legitimate answer.
+
+### About scale and language
+
+9. **How many notes, realistically?** Several choices below flip at around ten
+   thousand: the list payload, the search fallback, rendering the whole list.
+10. **Which languages?** The folding described under *Search* is Danish. Every
+    language has its own version of that problem and the generic answer (strip
+    diacritics) is wrong for several of them.
+11. **Where does the text end up besides the screen?** Search indexes, AI
+    features, exports and backups each read it. Plaintext makes all of them cheap
+    and makes a stolen backup expensive — see *What is still open*.
+
+### About integration, specifically
+
+12. **Who owns the note's identity — you or the other system?** If notes will sync
+    with something else, ids and timestamps are the whole problem, and the
+    `updated_at` rule below becomes the first thing you have to change.
+13. **Is this a read of somebody else's notes, or the store of record?** A copy
+    needs conflict rules; a store of record needs export.
+14. **What happens to a note whose project, task or link target is deleted?**
+    Answered here as "the link goes dead and the note is untouched". If your host
+    app cascades instead, say so before the first delete.
+
+---
+
+## The shape of a note
+
+```
+id           an opaque string, unique
+project_id   nullable — where it is filed, or loose
+title        derived, never set by a caller
+body         Markdown, the whole note
+created_by   nullable — survives the account being deleted
+pinned       favourite; the list puts these first
+archived_at  nullable timestamp — put away, not thrown away
+deleted_at   nullable timestamp — the trash
+created_at
+updated_at
+```
+
+### Markdown in a column
+
+Not rich text, and not a format of our own.
+
+Export was a requirement before a line was written, and **if the stored form is
+the exported form there is no conversion left to lose anything in.** A note stays
+readable by any editor on the day the program is gone. It is also what makes
+search and anything an AI does over notes cheap: both read text.
+
+The cost is real and you should know it before choosing: everything the editor can
+do has to survive a round trip through Markdown, and anything Markdown cannot say,
+the editor must not offer. There is no place to hide a feature.
+
+### The title is the first line
+
+Always, and re-derived on every save — not "when it is empty".
+
+Derived once and then left alone, a title goes stale the moment somebody rewrites
+the opening of a note, and the list ends up calling a note by a name that is
+nowhere in it. **The column is a cache of the body, not a field beside it**, and no
+caller can set it, so every caller gets the same answer.
+
+This forces one editor rule: a new note opens on its title, and the first line is
+styled as a heading. Otherwise a note whose first line is a sentence is a note
+named by its first sentence.
+
+### Archive and trash are two different bits
+
+The trash says *this was a mistake, and in thirty days it is gone*. The archive
+says *this is finished, and I do not want to read past it.*
+
+A twelve-hundred-note import is exactly the case where most notes are worth
+keeping and almost none are worth looking at. Without an archive, the list is the
+whole archive forever, and finding this week's note means reading past a decade.
+
+Both are nullable timestamps rather than booleans: *when was this put away* answers
+questions a flag cannot, and it costs the same byte.
+
+---
+
+## Filing: no hierarchy of its own
+
+A note belongs to a project, or to nobody.
+
+The reasoning is worth repeating because it is easy to talk yourself out of:
+projects already exist, are already shared, already have roles, already have a
+trash. **A second hierarchy to file things in is one too many**, and a note filed
+under a project inherits every one of those answers instead of needing its own.
+
+- A note with a project: everybody who can read the project can read the note; an
+  editor can change it.
+- A note without one: the author's, and nobody else's.
+
+Sharing a note *is* filing it in a project. There is no access list of its own —
+a second way to give somebody access is a second place to get it wrong, and the
+two would disagree the day one of them changed.
+
+---
+
+## Links: three kinds, parsed out of the text
+
+The body is the truth. Links are an index over it, rebuilt on every save.
+
+| Syntax | Means | Notes |
+|---|---|---|
+| `#project` | a project | Same characters the task quick-add parser uses, on purpose |
+| `[[a note]]` | another note, by title | The spelling every note app has settled on |
+| `/opgave/<uuid>` or `task:<uuid>` | a task | What a link pasted out of the app carries |
+
+Patterns as used here:
+
+```
+project   (?:^|\s)#([\p{L}\p{N}_-]{1,64})
+note      \[\[([^\]\n]{1,200})\]\]
+task      (?:/opgave/|task:)([0-9a-fA-F-]{36})
+```
+
+Three decisions inside that table:
+
+- **`#Firma` in a note means the same project as `#Firma` in the task box.** Not a
+  second kind of tag that happens to look alike. That is the whole of "tag a note
+  and see it in the project".
+- **The link table is torn down and rebuilt on save, not diffed.** A body is small
+  and the set is small; a diff is a second description of the same fact, and it
+  can disagree with the text. That is the one thing this must never do.
+- **The target is not a foreign key.** A link to something deleted is a fact about
+  the note. It should read as a dead link rather than vanish, and it must not
+  block the delete.
+
+The index exists so the question can be asked **backwards**: *what has been written
+about this task?* Answering that by searching every note's prose would be too slow
+to leave a panel open on.
+
+---
+
+## Search
+
+Three layers, in the order they answer.
+
+### 1. Full-text, ranked
+
+FTS5 over `title`, `body` and a folded copy, with `unicode61 remove_diacritics 2`.
+
+Ranking is bm25 with **the title weighted ten times the body**. A word in the title
+is what the note is *about*; the same word once in a long body is a mention.
+
+This matters more than it sounds. Ordering by "last touched" is invisible with ten
+notes and useless with twelve hundred imported the same evening: searching "Tesla"
+answered with a note about nginx first and the note actually called "Tesla Model Y"
+second — which reads as a search that does not work, because from where the person
+is sitting it is one.
+
+### 2. Folding, for the language you are in
+
+`remove_diacritics` does not touch `ø`, `æ` or `å` — Unicode considers them
+letters in their own right, not accented forms. So a Dane cannot find "grøn" by
+typing "gron", which is how people type when the keyboard is not theirs.
+
+The answer here is a generated column carrying a transliterated copy:
+
+```
+ø,Ø → o     æ,Æ → ae     å,Å → aa
+```
+
+indexed alongside the body and **weighted the same as the body** — otherwise a
+folded match outranks an exact one.
+
+> **Ask, do not copy.** This mapping is Danish. German wants `ü → ue`, Swedish
+> disagrees with Danish about `ä`, and Turkish has a dotless `ı` that breaks
+> naive lowercasing entirely. Get the mapping from somebody who types the
+> language.
+
+### 3. A word inside a word
+
+An index is built of tokens, and a token is whatever the tokenizer decided was a
+word. `gamerule keepInventory true` is three of them, and the middle one is
+`keepinventory` — so a search for "keep inventory" asks for two words that are
+nowhere and gets nothing, while the note sits right there.
+
+A prefix query gets half of it: `keep*` matches, `inventory*` cannot, and the two
+are ANDed, so the half that works is thrown away by the half that cannot.
+
+**This is not exotic in a notes app.** A decade of notes is full of commands,
+identifiers and file names, and every one of them is several words the index
+thinks is one.
+
+So: the index answers first; when it has nothing, the text is read, and every term
+must appear somewhere in the note, in any word. A `LIKE '%term%'` over the folded
+column covers title, body and language folding at once.
+
+What it costs: a leading `%` cannot use an index, so it scans. At twelve hundred
+notes that is a few megabytes and a millisecond or two, and it only runs when the
+fast path already came back empty — which is exactly the search that was about to
+disappoint somebody. **At a hundred thousand notes it is the wrong shape**, and the
+answer then is a trigram index, not a bigger scan.
+
+It does not rank. There is no match to rank — that is the whole situation.
+
+---
+
+## The list, and why the body is empty in it
+
+A list showing a title and ninety characters of preview must not fetch whole
+notes. Twelve hundred notes came to 3.9 MB, of which 98 % was body nobody could
+see.
+
+The important half is *how* it is trimmed: **the body is emptied, not shortened.**
+
+A field called `body` holding a *piece* of the body is a trap. The editor opens
+it, the autosave pause writes it back, and the note is now cut down to its own
+excerpt — destroyed by nothing more than having been looked at. Send `preview` as
+its own field and leave `body` empty; the client sees the empty body and fetches
+the whole note.
+
+That costs one more separation, and it is not optional:
+
+> **Which row is selected and which note is loaded are two different things.**
+
+The editor loads its text when the note's id changes. Hand it the excerpt first
+and the whole note second and the id is the same both times — so the second one
+never renders, and somebody sits looking at a note that had a title a moment ago.
+
+Highlight the row immediately from the list; give the editor the note only when it
+is whole.
+
+Rendering cost, separately: with twelve hundred rows, first paint took 2.1 s. CSS
+`content-visibility: auto` with an intrinsic-size guess took it to 0.95 s with no
+virtual list, no scroll maths, and no list that can fall out of step with itself.
+Try that before building windowing.
+
+---
+
+## The editor contract
+
+Rich text on top, Markdown underneath, and a source view that shows the file.
+
+The supported subset — deliberately small, because everything in it has to survive
+the round trip:
+
+| Block | Markdown |
+|---|---|
+| Title | `# ` |
+| Heading | `## ` |
+| Subheading | `### ` |
+| Quote | `> ` |
+| Code block | ```` ``` ```` with an optional language |
+| Bullet and numbered lists | `- `, `1. `, nested |
+
+Inline: `**bold**`, `*italic*`, `~~strikethrough~~`, `` `code` ``, `<u>underline</u>`,
+and images as `![alt](url)`.
+
+Five rules that were each learned the hard way:
+
+1. **Every line becomes exactly one block.** Markdown normally joins consecutive
+   lines into a paragraph. Here it must not: the person typed a line and expects
+   to get it back, and an editor that silently reflows what somebody wrote is an
+   editor they stop trusting.
+2. **Load on id change, never while typing.** Writing to the editor's HTML puts
+   the caret back at the start, which mid-sentence is unusable.
+3. **One definition of what a code block contains.** A copy button inside the
+   `<pre>` and a syntax highlighter reading `textContent` will disagree, and the
+   difference ends up in the file — a click on "Copy" wrote the word *Copied* into
+   the code and the next save put it on disk. Have one function that says what a
+   block holds, used by the highlighter and the Markdown serialiser both.
+4. **A note that cannot be rendered must not take the pane with it.** One note
+   arriving in an unexpected shape threw inside the editor's reactive effect, and
+   from then on *no* note would open — the previous one just stayed on screen. Put
+   a guard around the render, fall back to showing the raw text, and let the rest
+   of the pane keep working.
+5. **Escaping between tags and escaping inside an attribute are different jobs.**
+   An escaper written for text between two tags handles `&`, `<`, `>` — and not
+   quotes, because between tags they are harmless. Inside an attribute they close
+   it. `![" onerror="alert(1)](…)` is the whole exploit.
+
+---
+
+## Attachments
+
+Images pasted or dragged into a note, stored content-addressed by hash, referenced
+from the body as ordinary Markdown images.
+
+The security shape, which is the part worth copying:
+
+- **Served as `application/octet-stream` with `nosniff` by default.** Attachments
+  are the one place a user supplies content another user opens. An uploaded SVG or
+  HTML file rendered inline runs its own script on your origin with the session
+  cookie attached.
+- **One exception, as a named allowlist:** a short list of raster image types
+  served inline as their exact type — `png`, `jpeg`, `gif`, `webp`, `avif`, `heic`.
+  A note carries its pictures in the text, and served as octet-stream every one of
+  them is a broken image.
+- **The list is named one type at a time, never matched on an `image/` prefix.**
+  The prefix lets `image/svg+xml` through, and an SVG is a document that can run
+  script.
+- **The stored path is checked against the files directory again at read time.** A
+  traversal that somehow got into the database must not become one that reads
+  `/etc/passwd`.
+- **Reaching an attachment follows the note, which follows its project.** Same
+  chain as everything else. Do not let a client hand you the parent id and take it
+  on trust.
+
+---
+
+## Import and export
+
+The same format both ways: **a zip of Markdown files**, one per note, with a YAML
+front matter block.
+
+```markdown
+---
+created: 2019-04-02T10:15:00Z
+modified: 2024-11-30T21:04:00Z
+---
+
+# Møde med Anders
+
+Han vil gerne have kaffe hver uge.
+```
+
+- `created` / `created_at` / `date` and `modified` / `updated` / `updated_at` are
+  all accepted on the way in. Obsidian and Bear write this block; so should you.
+- Images travel in the zip beside the notes, and the links in the text are
+  relative — **a note and its pictures must end up in the same archive**, which
+  matters the moment an export is split into parts.
+- File names collide: two notes called "Møde" are two notes, and a zip with one
+  entry twice is a zip that loses one.
+
+Limits that a real import taught, all of them cheap to add and expensive to omit:
+
+- A ceiling on the upload, on the number of entries, and on the **unpacked** size.
+  64 MB of zip expanded to 66 GB is a normal shape for an attack.
+- A per-file limit as well as a whole-archive budget: one enormous photograph and
+  ten thousand small ones are different attacks with the same ending.
+- The entry name is never used as a path. Store by hash; the name is only a key
+  for rewriting links.
+- **Count what you skip, and say so.** A note whose name contained an ellipsis was
+  dropped silently by a filter looking for `..` — one out of 1141, found only by
+  counting at both ends.
+
+### Timestamps on the way in
+
+An importer needs to write `created_at` and `updated_at` from the file, and the
+normal save path must refuse to let it.
+
+`updated_at` means *when did this program last write this note*. Let any caller set
+it and the column means whatever the last writer felt like. Give the importer its
+own narrow entry point instead, and say in the comment why it exists.
+
+Without those dates, a move of twelve hundred notes is a pile that was all written
+the same evening — and the order they were written in is half of what an archive
+is.
+
+---
+
+## What is still open here
+
+Written down because a specification that only lists what works is a specification
+that lies by omission.
+
+- **Note bodies are plaintext at rest.** They hold API keys and passwords, and
+  they are in every backup anybody can download. Encrypting them is bigger than it
+  sounds: the body is in the full-text index and the folded column is generated
+  from it, so both are a second plaintext copy in the same database. Encrypt and
+  both have to go, and search has to be rewritten to decrypt in application code —
+  fine at a thousand notes, a full scan per keystroke at ten thousand, at which
+  point the answer is a keyed index (an HMAC per word).
+- **Import never merges.** Every run creates new notes. Say so out loud in the UI.
+- **There is no sync.** Export and the API are the way out.
+
+---
+
+## A short list of the traps, for the person in a hurry
+
+1. A `body` field holding an excerpt will be saved over the real one.
+2. Selected row and loaded note are two different pieces of state.
+3. The title must be re-derived on every save or it goes stale.
+4. Diacritic stripping is not folding, and folding is language-specific.
+5. A tokenizer cannot see a word inside a word; decide what you do about it.
+6. An attachment served inline is a script on your origin unless you allowlist by
+   exact type and send `nosniff`.
+7. Escaping for text and escaping for attributes are different functions.
+8. One render failure must not be allowed to freeze the whole pane.
+9. An unpacked-size limit is not optional on an archive import.
+10. Let the importer set timestamps; let nobody else.

README.md

@@ -6,7 +6,7 @@
 </p>
 
 <p align="center">
-  <img src="site/screenshots/today.png" alt="The Today view: projects, filters and labels in the sidebar, beside the tasks due today." width="900">
+  <img src="docs/screenshots/today.png" alt="The Today view: projects, filters and labels in the sidebar, beside the tasks due today." width="900">
 </p>
 
 ---
@@ -35,6 +35,11 @@ mail-to-task address, and an MCP endpoint so Claude can work your task list dire
   in Firma, labelled regnskab. Danish and English, mixed freely in one line.
 - **Projects, sections, sub-tasks, labels, saved filters.** List, board and calendar
   views, and foldable groups over the projects in the sidebar.
+- **Notes, beside the work.** Rich text that is Markdown underneath — headings,
+  lists, quotes, fenced code. A note is shared by filing it in a project;
+  `#project` and `[[another note]]` are links, and a task shows the notes that
+  mention it. A zip of Markdown goes in — Obsidian, Bear, or Apple Notes through
+  the exporter in [`tools/`](tools/) — and comes back out the same shape.
 - **Drag where it means something.** Reorder a list or a board, file a project under
   a group, drop a task on another project, or drop it on another day.
 - **Sharing.** Owner, editor and viewer roles. There is no open registration:
@@ -90,21 +95,24 @@ Apple Reminders, forward mail into it, and add it to Claude as a connector.
 | Project templates | Done, tested |
 | Nightly backups with rotation | Done, tested |
 | Comments, attachments, notifications, Web Push | Built |
+| Notes: rich text, Markdown on disk, links to projects, notes and tasks | Done, tested |
+| Notes in and out: a zip of Markdown, both directions | Done, tested |
 | Todoist CSV import and export, account export | Done, tested |
 | MCP server for Claude | Done, tested |
 | CalDAV server (two-way VTODO) | Done, tested |
 | Mail-to-task | Done, tested |
 | AI layer (Anthropic/OpenAI/Google/local) | Built, degrades when unconfigured |
 | Gmail: OAuth2 with PKCE, polling, one-way to tasks | Done, tested |
+| Google Calendar: read-only, laid over the task calendar | Built, never run against Google |
 | Update notice for administrators | Done, tested |
 | Personal API tokens | Done, tested |
 | OpenAPI 3.1 spec, checked against the router | Done, tested |
 | End-to-end smoke tests (Playwright) | Done |
 | Documentation, landing page, licence | Done |
 
-**Not finished:** Web Push, the AI providers and the Gmail API calls are
-implemented against their specifications and have only ever been exercised there,
-not against live services. Everything else has an interface: opening a task shows
+**Not finished:** Web Push, the AI providers, and the Gmail and Google Calendar
+API calls are implemented against their specifications and have only ever been
+exercised there, not against live services. Everything else has an interface: opening a task shows
 its description, sub-tasks, comments, files and reminders, and the settings pages
 cover the account, notifications, integrations, AI, API tokens, import, export and
 templates.
@@ -116,17 +124,20 @@ accented `o` and a Danish-first app that cannot do this is broken for its own us
 
 | | |
 |---|---|
-| ![Board view](site/screenshots/board.png) | ![Light theme](site/screenshots/today-light.png) |
+| ![Board view](docs/screenshots/board.png) | ![Light theme](docs/screenshots/today-light.png) |
 | Board view — one column per section. | The light theme. |
-| ![A week on Upcoming](site/screenshots/week.png) | ![A task, opened](site/screenshots/detail.png) |
-| A week at a time, so a task can be dragged across a month boundary. | A task, opened. |
-| ![The five themes](site/screenshots/themes.png) | ![Instance history](site/screenshots/history.png) |
-| Five themes, all measured for contrast. | What has been done on the server. |
+| ![A week on Upcoming](docs/screenshots/week.png) | ![A task, opened](docs/screenshots/detail.png) |
+| A week at a time, so a task can be dragged across a month boundary. | A task, opened: description, priority, labels, sub-tasks and its files. |
+| ![Notes](docs/screenshots/notes.png) | ![The same note as Markdown](docs/screenshots/notes-source.png) |
+| Notes, filed in a project to share them. | The same note as its source — which is what the export writes to disk. |
+| ![Themes and looks](docs/screenshots/themes.png) | ![Instance history](docs/screenshots/history.png) |
+| Five themes and four looks: how bright, and how it reads. | What has been done on the server. |
 
 Regenerate these with `node scripts/generate-screenshots.js` from `web/`. It starts
-the real binary, creates its own account, fills it with demo data and photographs
-eleven surfaces — nothing to set up and nothing to remember. (`go run ./tools/shots`
-still works, and is the way to photograph an instance that is already running.)
+the real binary, creates its own account and a second one to share with, fills them
+with demo data and photographs fourteen surfaces — nothing to set up and nothing to
+remember. (`go run ./tools/shots` still works, and is the way to photograph an
+instance that is already running.)
 
 ## Running it
 

SECURITY.md

@@ -10,13 +10,28 @@ reply within a week.
 
 - **Passwords** are Argon2id with the parameters recorded in the hash, so they can
   be raised later without locking anyone out.
-- **Every token** — session, invite, reset, API, calendar feed, mail address — is
-  stored only as a SHA-256 hash. A database dump contains nothing that can be
-  presented.
+- **Session, invite, reset and API tokens** are stored only as a SHA-256 hash. A
+  database dump contains nothing that can be presented.
+- **The calendar feed address and the mail-to-task address are not hashed.** They
+  are looked up by their exact value, and they are shown in the interface more
+  than once, which a hash cannot do. Anybody holding a backup file therefore holds
+  those two URLs: the feed reads that person's tasks without a login, and the mail
+  address files tasks into their inbox. Rotating either from **Settings →
+  Integrations** invalidates the old one. This is written down rather than fixed
+  because fixing it means the address can only ever be shown once, which is a
+  decision about how the feature works and not only about how it is stored.
+- **Mailbox passwords, OAuth tokens, TOTP secrets and AI keys** are sealed with
+  AES-GCM under a key kept outside the database — see `internal/secret`. That is
+  what makes a stray copy of the database less than a stray copy of everything:
+  the backup does not carry the key.
 - **Sessions** are `httpOnly`, `SameSite=Lax`, and `__Host-` prefixed over HTTPS.
-- **Uploads** are stored content-addressed by hash and always served as
-  `application/octet-stream` with `nosniff`, so an uploaded SVG cannot run script
-  on this origin.
+- **Uploads** are stored content-addressed by hash and served as
+  `application/octet-stream` with `nosniff` — with one exception, added so that a
+  note can show the pictures in it: a short allowlist of raster image types is
+  served inline as its own type. The list is named one format at a time rather
+  than matched on an `image/` prefix, because the prefix would let `image/svg+xml`
+  through, and an SVG is a document that can run script. `nosniff` stays, so the
+  browser must read the file as that image or not at all.
 - **The filter language** compiles to parameterised SQL. No typed text is ever
   concatenated into a statement.
 - **Permission checks** are route middleware, and anything you may not see answers

cmd/verdande/main.go

@@ -75,7 +75,9 @@ func run() error {
 	runner := jobs.New(cfg, db, log, api.Mail(), api.Hub())
 	runner.SyncGmail = api.SyncGmail
 	runner.SyncMailbox = api.SyncMailbox
+	runner.SyncCalendars = api.SyncCalendars
 	runner.Push = api.PushToUser
+	runner.SendBeacon = api.SendBeacon
 	runner.Start(jobCtx)
 
 	srv := &http.Server{

docs/caldav.md

@@ -1,13 +1,14 @@
 # Calendar and CalDAV
 
-Two ways to get your tasks into a calendar, and they are not the same thing.
+Two ways to get your tasks into a calendar, one way to get a calendar into
+verdande, and none of the three is the same thing.
 
-| | [Feed](#subscribing-to-a-feed) | [CalDAV](#connecting-a-caldav-client) |
-|---|---|---|
-| Direction | Read only | Two-way |
-| Works with | Anything that subscribes to a URL | Apple Reminders, Thunderbird, DAVx⁵ |
-| You can tick things off | No | Yes |
-| Setup | Paste a URL | Username and token |
+| | [Feed](#subscribing-to-a-feed) | [CalDAV](#connecting-a-caldav-client) | [Google Calendar](#showing-a-google-calendar-in-verdande) |
+|---|---|---|---|
+| Direction | Tasks out, read only | Tasks out, two-way | Events **in**, read only |
+| Works with | Anything that subscribes to a URL | Apple Reminders, Thunderbird, DAVx⁵ | A Google account |
+| You can tick things off | No | Yes | No — an event is not a task |
+| Setup | Paste a URL | Username and token | Connect, then pick calendars |
 
 ## Subscribing to a feed
 
@@ -39,6 +40,42 @@ most people actually keep.
     **Settings → Calendar feed → Rotate** issues a new one and breaks the old
     immediately.
 
+## Showing a Google calendar in verdande
+
+The two sections above send your tasks *out*. This is the other direction: your
+Google calendar drawn underneath them, so one screen answers "what does this day
+already have in it".
+
+**Settings → Integrations → Google Calendar → Connect**, then tick the calendars
+you want and press Save. They appear in **Calendar** in the sidebar, in Google's
+own colour for each one, beside your own tasks with due dates.
+
+It needs the same OAuth client Gmail uses, with the Calendar API enabled and the
+second redirect URI registered — see [Configuration](configuration.md#google).
+
+!!! warning "Read only"
+    verdande never writes to your Google calendar. An event cannot be dragged,
+    edited or ticked off here; clicking one opens it in Google, which is where it
+    can be changed. Your own tasks in the same grid still drag to another day as
+    they always have.
+
+    Writing would need the `calendar.events` scope and an answer to what should
+    happen when both sides moved the same meeting — which is a synchronisation
+    model rather than a scope, and it is deliberately not built yet.
+
+!!! note "The Internal client applies here too"
+    An OAuth client registered as *Internal* in a Google Workspace can only be
+    used by accounts in that workspace, calendars included. A personal
+    `@gmail.com` address is refused with `org_internal`. For one personal account
+    the shorter road is the calendar's own secret address: in Google Calendar,
+    **Settings → the calendar → Integrate calendar → Secret address in iCal
+    format**. Nothing in verdande subscribes to one yet — it is the next piece of
+    this feature.
+
+Events are kept for ninety days back and a year forward, refreshed every fifteen
+minutes and whenever you press **Fetch now**. Paging the grid past that window
+says so rather than showing an empty month.
+
 ## Connecting a CalDAV client
 
 This is the one where ticking something off in Apple Reminders ticks it off here.

docs/configuration.md

@@ -39,12 +39,24 @@ Any Go duration: `720h`, `30m`, `45s`.
     yourself, password resets are written to the log, and reminders arrive in the
     app and as Web Push rather than by email.
 
-## Gmail
+## Google
 
-Only needed if anyone will connect a mailbox. Register an OAuth client in Google
-Cloud (**APIs & Services → Credentials → OAuth client ID → Web application**) with
-the redirect URI `https://your-address/oauth/gmail/callback`, enable the Gmail API,
-and add the `gmail.readonly` scope.
+Only needed if anyone will connect a Gmail mailbox or a Google calendar. One
+registration covers both: register an OAuth client in Google Cloud
+(**APIs & Services → Credentials → OAuth client ID → Web application**) and add
+**both** redirect URIs:
+
+```
+https://your-address/oauth/gmail/callback
+https://your-address/oauth/calendar/callback
+```
+
+Then enable the APIs and scopes for whichever you want:
+
+| For | Enable | Scope |
+|---|---|---|
+| Mailboxes | Gmail API | `gmail.readonly` |
+| Calendar | Google Calendar API | `calendar.readonly` |
 
 | Variable | What it does |
 |---|---|
@@ -52,8 +64,15 @@ and add the `gmail.readonly` scope.
 | `VERDANDE_GMAIL_CLIENT_SECRET` | The client secret. |
 
 One registration serves every user on the instance; each person authorises their
-own mailbox from **Settings → Gmail**. The redirect URI is derived from
-`VERDANDE_BASE_URL`, so it cannot drift out of step with what you registered.
+own mailbox from **Settings → Integrations → Gmail** and their own calendar from
+**Settings → Integrations → Google Calendar**. Both redirect URIs are derived from
+`VERDANDE_BASE_URL`, so they cannot drift out of step with what you registered.
+
+!!! note "Two connections, two grants"
+    Connecting a calendar does not disturb a working Gmail connection, and
+    disconnecting one does not take the other with it. Google issues a refresh
+    token per authorisation and keeps up to a hundred of them live per account,
+    each carrying only the scopes it was granted with.
 
 ## Secrets
 

docs/index.md

@@ -22,6 +22,9 @@ forward mail to, and an MCP endpoint so Claude can work your task list directly.
   Firma, labelled regnskab. Danish and English, mixed freely in one line.
 - **Projects, sections, sub-tasks, labels, [saved filters](filters.md).** List,
   board and calendar views, and foldable groups over the projects in the sidebar.
+- **Notes, beside the work.** Rich text to write in, Markdown on disk. A note is
+  shared by filing it in a project; `#project` and `[[another note]]` are links,
+  and a task shows what has been written about it.
 - **Drag where it means something** — reorder a list or a board, file a project
   under a group, drop a task on another project, or drop it on another day.
 - **Sharing** with owner, editor and viewer roles. Anyone outside your instance
@@ -31,6 +34,33 @@ forward mail to, and an MCP endpoint so Claude can work your task list directly.
 - **[Calendar](caldav.md), [mail](mail.md) and [Claude](mcp.md)** connected over
   open standards rather than private formats.
 
+## What it looks like
+
+![Upcoming as a month](screenshots/upcoming.png)
+
+*Upcoming, as a month. A week and a plain list are the other two, and a task can be
+dragged from one day onto another.*
+
+![A project as a list](screenshots/sections.png)
+
+*The same project as a list, where sections read as bands. As a board they are
+columns.*
+
+![Waiting on others](screenshots/delegated.png)
+
+*What you have handed to somebody else, grouped by whoever has it.*
+
+![Settings, integrations](screenshots/settings.png)
+
+*Where [Gmail](mailboxes.md), the [calendar feed](caldav.md) and the
+[mail-to-task address](mail.md) are connected.*
+
+![Settings, people](screenshots/admin.png)
+
+*Inviting somebody to the instance. There is no open registration — everybody
+arrives through a link, and picks their own password. See
+[signing in](signing-in.md).*
+
 ## Getting it running
 
 verdande is built to be deployed as a **Rune** in

docs/mailboxes.md

@@ -16,7 +16,7 @@ administrator who can read yours.
 **Settings → Integrations → Gmail → Connect.**
 
 Gmail needs an OAuth client, which is the instance's registration with Google
-rather than anybody's account — see [Configuration](configuration.md#gmail).
+rather than anybody's account — see [Configuration](configuration.md#google).
 Once it is set up, each person connects their own mailbox through it.
 
 Choose what makes a task:

docs/openapi.yaml

@@ -263,6 +263,36 @@ paths:
         "204": { description: Saved. }
         "400": { $ref: "#/components/responses/BadRequest" }
 
+  /api/v1/auth/nav-order:
+    put:
+      tags: [auth]
+      summary: The order of the fixed views in the sidebar.
+      description: |
+        I dag, Kommende, Venter and the inbox, in whatever order this person wants
+        them. On the account rather than in the browser: which order you want them
+        in is a fact about you and should be the same on the phone as on the laptop.
+
+        A list of keys rather than a number per view. The set of views changes with
+        the program, and a key that no longer exists costs nothing — the sidebar
+        draws what it recognises and appends anything new at the end, which is what
+        makes adding a view later not a migration. An empty list means the order the
+        program ships with.
+      requestBody:
+        required: true
+        content:
+          application/json:
+            schema:
+              type: object
+              properties:
+                order:
+                  type: array
+                  maxItems: 20
+                  items: { type: string }
+                  example: ["inbox", "today", "upcoming", "delegated"]
+      responses:
+        "204": { description: Saved. }
+        "400": { $ref: "#/components/responses/BadRequest" }
+
   /api/v1/auth/me:
     get:
       tags: [auth]
@@ -1366,6 +1396,204 @@ paths:
                     description: The environment variables that are not set.
         "403": { $ref: "#/components/responses/Forbidden" }
 
+  /api/v1/notes/bulk:
+    post:
+      tags: [notes]
+      summary: Archive, unarchive or delete a set of notes in one call.
+      description: |
+        One call rather than one per note, because the thing being asked is one
+        thing: "put these away". Fifty separate requests would be fifty round
+        trips, fifty chances for half of them to fail, and a list that redraws
+        fifty times — and after an import of twelve hundred notes, selecting fifty
+        is the ordinary case rather than the extreme one.
+
+        Each note is still checked on its own. A set is a convenience for the
+        caller and never a way to touch something they could not have touched one
+        at a time; anything they may not write to is counted in `skipped` rather
+        than failing the whole call, so one note somebody else just deleted does
+        not stop the other forty-nine.
+
+        Archiving is not deleting. The trash says "this was a mistake, and in
+        thirty days it is gone"; the archive says "this is finished, and I want to
+        keep it".
+      requestBody:
+        required: true
+        content:
+          application/json:
+            schema:
+              type: object
+              required: [ids]
+              properties:
+                ids:
+                  type: array
+                  items: { type: string }
+                  description: At most 500.
+                archived:
+                  type: boolean
+                  description: Put away, or bring back out.
+                delete:
+                  type: boolean
+                  description: Into the trash instead. Wins over `archived`.
+      responses:
+        "200":
+          description: How many were changed, and how many were passed over.
+          content:
+            application/json:
+              schema:
+                type: object
+                properties:
+                  done: { type: integer }
+                  skipped: { type: integer }
+        "422":
+          description: No ids, too many, or neither archived nor delete was asked for.
+
+  /api/v1/notes/{noteID}/attachments:
+    post:
+      tags: [notes]
+      summary: Put a file into a note.
+      description: |
+        A picture pasted or dropped into a note. Until this existed the import
+        could bring files in and nothing else could, so the most ordinary act in
+        a notes app — paste a screenshot — did nothing at all.
+
+        Editor rights on the note. The same answer for "no such note" and "not
+        yours", so an id cannot be probed.
+
+        The response carries the attachment's URL; the editor writes that into the
+        note's text as a Markdown image. The file is never inlined as a data URL —
+        a photograph as base64 would make the note itself megabytes of text.
+      parameters:
+        - name: noteID
+          in: path
+          required: true
+          schema: { type: string }
+      requestBody:
+        required: true
+        content:
+          multipart/form-data:
+            schema:
+              type: object
+              required: [file]
+              properties:
+                file:
+                  type: string
+                  format: binary
+      responses:
+        "201":
+          description: Stored, and hung on the note.
+        "404":
+          description: No such note, or not yours to write in.
+        "413":
+          description: Larger than 25 MB.
+
+  /api/v1/beacon:
+    post:
+      tags: [auth]
+      summary: Report that an installation exists. Unauthenticated.
+      description: |
+        The receiving end of the beacon. Open on purpose: the caller is a
+        stranger's installation, which is the whole feature.
+
+        Answers 404 unless this instance has been told it is the collector, so an
+        ordinary installation is not a spam sink that answers 200 to anything.
+        Rate limited like the login routes, and the table behind it has a ceiling:
+        the endpoint inserts a row keyed on an id the caller invented, so without
+        one anybody could grow it until the volume is full.
+
+        Nothing about the request is recorded but the two values in the body. No
+        source address is read or written here.
+      requestBody:
+        required: true
+        content:
+          application/json:
+            schema:
+              type: object
+              required: [instance_id]
+              properties:
+                instance_id:
+                  type: string
+                  description: A random id the installation generated for itself.
+                version:
+                  type: string
+      responses:
+        "204":
+          description: Recorded.
+        "400":
+          description: The id or the version is not the expected shape.
+        "404":
+          description: This instance is not a collector.
+
+  /api/v1/beacon/count:
+    get:
+      tags: [auth]
+      summary: How many installations reported in the last thirty days.
+      description: |
+        Unauthenticated and cached for a minute, and only answered when the
+        collector has been told to publish it.
+
+        A window rather than a running total: a total only climbs, so it stops
+        meaning "how many people use this" and starts meaning "how many ever
+        tried it".
+      responses:
+        "200":
+          description: The count.
+          content:
+            application/json:
+              schema:
+                type: object
+                properties:
+                  installs: { type: integer }
+                  window_days: { type: integer }
+        "404":
+          description: Not a collector, or not published.
+
+  /api/v1/beacon/settings:
+    get:
+      tags: [auth]
+      summary: What this instance reports, and to whom. Administrators only.
+      description: |
+        Includes the exact payload that will be sent, so the settings page can
+        print it in full rather than describe it.
+      responses:
+        "200":
+          description: The current configuration, and the counts if this is the collector.
+          content:
+            application/json:
+              schema:
+                type: object
+                properties:
+                  enabled: { type: boolean }
+                  collector_url: { type: string }
+                  instance_id: { type: string }
+                  version: { type: string }
+                  is_collector: { type: boolean }
+                  publish_count: { type: boolean }
+                  last_ping_at: { type: string, format: date-time }
+    put:
+      tags: [auth]
+      summary: Turn the beacon off, or point it somewhere else. Administrators only.
+      requestBody:
+        required: true
+        content:
+          application/json:
+            schema:
+              type: object
+              properties:
+                enabled: { type: boolean }
+                collector_url:
+                  type: string
+                  description: |
+                    Where reports go. Fetched through a dialer that refuses
+                    loopback and private address space, so this cannot be used to
+                    make the server reach inside its own network.
+                is_collector: { type: boolean }
+                publish_count: { type: boolean }
+      responses:
+        "200":
+          description: The configuration as it now stands.
+        "422":
+          description: The collector address is not an http or https URL.
+
   /api/v1/panel/restart:
     post:
       tags: [auth]
@@ -1821,6 +2049,125 @@ paths:
         "404": { $ref: "#/components/responses/NotFound" }
         "422": { $ref: "#/components/responses/Validation" }
 
+  /api/v1/projects/{projectID}/sections/reorder:
+    parameters:
+      - { name: projectID, in: path, required: true, schema: { type: string } }
+    post:
+      tags: [projects]
+      summary: Set the order the project's sections appear in. Editors and owners.
+      description: |
+        The whole list at once, for the same reasons as `/projects/reorder`: a
+        project has a handful of sections, so sending the order you want is
+        simpler than midpoints and cannot land half-applied.
+
+        Ids belonging to another project are skipped rather than refused.
+      requestBody:
+        required: true
+        content:
+          application/json:
+            schema:
+              type: object
+              required: [ids]
+              properties:
+                ids:
+                  type: array
+                  maxItems: 500
+                  items: { type: string }
+                  description: Section ids, top to bottom.
+      responses:
+        "204": { description: Reordered. }
+        "404": { $ref: "#/components/responses/NotFound" }
+        "422": { $ref: "#/components/responses/Validation" }
+
+  /api/v1/calendar/subscriptions:
+    post:
+      tags: [calendar]
+      summary: Subscribe to a calendar you only have an address to.
+      description: |
+        An ICS or `webcal://` address. Several per person, unlike the Google
+        connection, which is one — the address is the identity here, the way the
+        token is for OAuth.
+
+        The address is fetched once before it is stored: an address that cannot be
+        read is a typo far more often than a server that happens to be down, and
+        saying so while somebody is still looking at the field is worth two
+        seconds. `webcal://` is rewritten to `https://`, and the destination is
+        checked against the private-network wall both when it is written down and
+        again on the resolved address every time it is fetched.
+      requestBody:
+        required: true
+        content:
+          application/json:
+            schema:
+              type: object
+              required: [url]
+              properties:
+                url: { type: string, description: "https:// or webcal://" }
+                name:
+                  type: string
+                  description: Optional. The calendar's own name is used when this is empty.
+      responses:
+        "201":
+          description: Subscribed, and fetched once.
+        "422": { $ref: "#/components/responses/Validation" }
+
+  /api/v1/calendar/subscriptions/{id}:
+    parameters:
+      - { name: id, in: path, required: true, schema: { type: string } }
+    delete:
+      tags: [calendar]
+      summary: Stop subscribing. The cached events go with it.
+      responses:
+        "204": { description: Gone. }
+        "404": { $ref: "#/components/responses/NotFound" }
+
+  /api/v1/push/test:
+    post:
+      tags: [notifications]
+      summary: Send one notification to your own devices, and say what happened.
+      description: |
+        The answer to "no notifications arrive". A push that a service refuses is
+        the ordinary failure — a stale subscription, a browser that revoked
+        permission without telling the server — and every one of them looks
+        exactly like silence from the outside.
+
+        It goes through the same path a real notification takes, so what it proves
+        is the thing that has to work. The title and body come from the caller
+        because the dictionaries live in the interface.
+      requestBody:
+        required: false
+        content:
+          application/json:
+            schema:
+              type: object
+              properties:
+                title: { type: string, maxLength: 200 }
+                body: { type: string, maxLength: 500 }
+      responses:
+        "200":
+          description: What each device did with it.
+          content:
+            application/json:
+              schema:
+                type: object
+                properties:
+                  subscriptions:
+                    type: integer
+                    description: Devices registered for this account.
+                  sent:
+                    type: integer
+                  failed:
+                    type: array
+                    items:
+                      type: object
+                      properties:
+                        service:
+                          type: string
+                          description: The push service's host — never the endpoint, which is a credential.
+                        reason:
+                          type: string
+                          description: What the service said.
+
   /api/v1/sections/{sectionID}:
     parameters:
       - { name: sectionID, in: path, required: true, schema: { type: string } }
@@ -2477,6 +2824,283 @@ paths:
                   created: { type: integer }
         "502": { $ref: "#/components/responses/Upstream" }
 
+  /api/v1/calendar:
+    get:
+      tags: [integrations]
+      summary: The Google Calendar connection and the calendars in it.
+      description: |
+        Read-only. verdande shows a Google calendar beside its own dated tasks and
+        never writes one back — writing needs the `calendar.events` scope and an
+        answer to what happens when both sides moved the same meeting, which is a
+        synchronisation model rather than a scope.
+
+        The list of calendars is fetched from Google when it is empty, so an
+        account that connected during a hiccup corrects itself on the next look
+        rather than showing an empty panel for ever.
+      responses:
+        "200": { $ref: "#/components/responses/Calendar" }
+    delete:
+      tags: [integrations]
+      summary: Disconnect the calendar and forget its tokens.
+      description: >
+        The cached events go too. Unlike the tasks a mailbox made, none of this is
+        the person's own work — it is a copy of somebody else's calendar, and it
+        means nothing without the account.
+      responses:
+        "204": { description: Disconnected. }
+
+  /api/v1/calendar/calendars:
+    put:
+      tags: [integrations]
+      summary: Choose which calendars are drawn.
+      description: >
+        The whole set in one write rather than one flip at a time, for the reason
+        the projects' order is written the same way: the question is "these ones",
+        and a list built out of several requests can land half applied. A calendar
+        turned off has its cached events removed; they come back if it is turned
+        on again.
+      requestBody:
+        required: true
+        content:
+          application/json:
+            schema:
+              type: object
+              properties:
+                shown:
+                  type: array
+                  items: { type: string }
+      responses:
+        "204": { description: Saved. }
+        "404": { $ref: "#/components/responses/NotFound" }
+
+  /api/v1/calendar/authorize:
+    post:
+      tags: [integrations]
+      summary: Begin the OAuth flow for a calendar.
+      description: |
+        The same registration Gmail signs in through, asking for
+        `calendar.readonly` and coming back to `/oauth/calendar/callback`. Google
+        issues a refresh token per authorisation, so connecting a calendar does not
+        disturb a working Gmail connection.
+      responses:
+        "200":
+          description: OK
+          content:
+            application/json:
+              schema:
+                type: object
+                properties:
+                  url: { type: string }
+        "409":
+          $ref: "#/components/responses/Conflict"
+
+  /api/v1/calendar/sync:
+    post:
+      tags: [integrations]
+      summary: Refresh the chosen calendars now.
+      description: >
+        Refreshes the list of calendars and replaces the cached window of events
+        for the ones that are shown. `partial` means the budget ran out before the
+        last calendar; what was read is kept, and the rest arrive on the next run.
+      responses:
+        "200":
+          description: OK
+          content:
+            application/json:
+              schema:
+                type: object
+                properties:
+                  events: { type: integer }
+                  partial: { type: boolean }
+        "502": { $ref: "#/components/responses/Upstream" }
+
+  /api/v1/calendar/events:
+    get:
+      tags: [integrations]
+      summary: The events of the chosen calendars, between two days.
+      description: |
+        Both ends inclusive, and an event that merely overlaps the range comes
+        back — a grid asks which cells an event covers, not where it begins.
+
+        `from` and `to` in the answer are the window verdande holds a copy of,
+        which is not the window that was asked for. A grid paged past it gets no
+        events, and an empty answer with no explanation is a calendar quietly
+        claiming a day is clear.
+      parameters:
+        - { name: from, in: query, required: true, schema: { type: string, format: date } }
+        - { name: to, in: query, required: true, schema: { type: string, format: date } }
+      responses:
+        "200":
+          description: OK
+          content:
+            application/json:
+              schema:
+                type: object
+                properties:
+                  events:
+                    type: array
+                    items: { $ref: "#/components/schemas/CalendarEvent" }
+                  from: { type: string, format: date }
+                  to: { type: string, format: date }
+        "422": { $ref: "#/components/responses/Validation" }
+
+  /api/v1/export/notes.zip:
+    get:
+      tags: [notes]
+      summary: Every note as a Markdown file, in a zip.
+      description: >
+        One file per note, named after its title, containing exactly what is
+        stored. Nothing is converted on the way out — the note on disk is already
+        the file you would export — so it opens in Obsidian, in a text editor, or
+        in anything else that reads Markdown.
+      responses:
+        "200":
+          description: A zip archive.
+          content:
+            application/zip:
+              schema: { type: string, format: binary }
+
+  /api/v1/notes:
+    get:
+      tags: [notes]
+      summary: Notes — listed, narrowed to a project, or searched.
+      description: >
+        With no parameters: the notes filed under no project, which are the
+        person's own. With `project`: that project's, which needs read access to
+        it. With `q`: a full-text search across every note they can see, matching
+        Danish spelling either way round — "grøn" finds "gron" and the reverse.
+      parameters:
+        - name: q
+          in: query
+          schema: { type: string }
+        - name: project
+          in: query
+          schema: { type: string }
+      responses:
+        "200":
+          description: OK
+          content:
+            application/json:
+              schema:
+                type: object
+                properties:
+                  notes:
+                    type: array
+                    items: { $ref: "#/components/schemas/Note" }
+    post:
+      tags: [notes]
+      summary: Write a note.
+      requestBody:
+        required: true
+        content:
+          application/json:
+            schema: { $ref: "#/components/schemas/NoteInput" }
+      responses:
+        "201":
+          description: Written
+          content:
+            application/json:
+              schema: { $ref: "#/components/schemas/Note" }
+        "403": { $ref: "#/components/responses/Forbidden" }
+
+  /api/v1/notes/import:
+    post:
+      tags: [notes]
+      summary: A zip of Markdown files becomes notes.
+      description: >
+        The mirror of the export, and the way in from anywhere else: a folder of
+        Markdown is what Obsidian, Bear, iA Writer and a shell script all produce.
+        Filenames are ignored — the title is the first line of the body, here as
+        everywhere, and taking it from the filename would be a second rule for the
+        same thing. Directories, macOS resource forks and anything that is not .md
+        are passed over.
+      requestBody:
+        required: true
+        content:
+          multipart/form-data:
+            schema:
+              type: object
+              properties:
+                file: { type: string, format: binary }
+      responses:
+        "200":
+          description: Read
+          content:
+            application/json:
+              schema:
+                type: object
+                properties:
+                  created: { type: integer }
+                  skipped: { type: integer, description: Files that were not usable as a note. }
+        "413": { description: The archive is too large. }
+
+  /api/v1/notes/{noteID}:
+    parameters:
+      - name: noteID
+        in: path
+        required: true
+        schema: { type: string }
+    get:
+      tags: [notes]
+      summary: One note.
+      responses:
+        "200":
+          description: OK
+          content:
+            application/json:
+              schema: { $ref: "#/components/schemas/Note" }
+        "404": { $ref: "#/components/responses/NotFound" }
+    patch:
+      tags: [notes]
+      summary: Change a note. Every field is optional; what is sent is what changes.
+      requestBody:
+        required: true
+        content:
+          application/json:
+            schema: { $ref: "#/components/schemas/NoteInput" }
+      responses:
+        "200":
+          description: OK
+          content:
+            application/json:
+              schema: { $ref: "#/components/schemas/Note" }
+        "404": { $ref: "#/components/responses/NotFound" }
+    delete:
+      tags: [notes]
+      summary: Put a note in the trash. It can be brought back.
+      responses:
+        "204": { description: Deleted }
+        "404": { $ref: "#/components/responses/NotFound" }
+
+  /api/v1/notes/linking/{kind}/{targetID}:
+    get:
+      tags: [notes]
+      summary: What has been written about this.
+      description: >
+        The backwards direction. A task's id gives every note that mentions it,
+        a project's name gives every note carrying that #tag.
+      parameters:
+        - name: kind
+          in: path
+          required: true
+          schema: { type: string, enum: [task, note, project] }
+        - name: targetID
+          in: path
+          required: true
+          schema: { type: string }
+      responses:
+        "200":
+          description: OK
+          content:
+            application/json:
+              schema:
+                type: object
+                properties:
+                  notes:
+                    type: array
+                    items: { $ref: "#/components/schemas/Note" }
+        "400": { $ref: "#/components/responses/BadRequest" }
+
   /api/v1/mailboxes:
     get:
       tags: [integrations]
@@ -2963,6 +3587,26 @@ paths:
       responses:
         "302": { description: "Back into the app, with the outcome as a query parameter." }
 
+  /oauth/calendar/callback:
+    get:
+      tags: [integrations]
+      summary: Where Google sends the browser after consent to a calendar.
+      description: |
+        A URI of its own rather than a reuse of Gmail's. One callback deciding from
+        stored state which of the two flows had come back would put the choice of
+        which token store to write behind a lookup — and when that goes wrong it
+        goes wrong by overwriting a working Gmail connection with calendar tokens.
+
+        Answers with a redirect to `/indstillinger/integrationer`, not with JSON.
+        An `org_internal` error here means the OAuth app is registered as Internal
+        and the account is outside the organisation.
+      parameters:
+        - { name: code, in: query, schema: { type: string } }
+        - { name: state, in: query, schema: { type: string } }
+        - { name: error, in: query, schema: { type: string } }
+      responses:
+        "302": { description: "Back into the app, with the outcome as a query parameter." }
+
   /mcp:
     post:
       tags: [integrations]
@@ -3145,6 +3789,40 @@ components:
               email: { type: string }
               trigger: { type: string, enum: ["", starred, label, both] }
               label: { type: string }
+    Calendar:
+      description: OK
+      content:
+        application/json:
+          schema:
+            type: object
+            properties:
+              connected: { type: boolean }
+              account:
+                type: string
+                description: >
+                  The address of the connected account, taken from the id of its
+                  primary calendar — which is where Google puts it, so no profile
+                  scope has to be asked for to learn it.
+              read_only:
+                type: boolean
+                description: >
+                  Always true today. Stated rather than assumed: an interface that
+                  quietly looks editable is one somebody will try to edit.
+              has_client:
+                type: boolean
+                description: >
+                  Whether an OAuth client is registered on this instance at all, so
+                  the page can explain rather than offer a button that answers 409.
+              redirect_uri:
+                type: string
+                description: >
+                  What has to be registered with Google, spelled out. Derived from
+                  VERDANDE_BASE_URL and matched exactly — the single most likely
+                  thing to be wrong, and the error Google gives names neither value.
+              last_sync_at: { type: string, format: date-time }
+              calendars:
+                type: array
+                items: { $ref: "#/components/schemas/Calendar" }
     ImportResult:
       description: Created
       content:
@@ -3162,6 +3840,89 @@ components:
                 items: { type: string }
 
   schemas:
+    Calendar:
+      type: object
+      description: >
+        One calendar inside a connected account. Kept whether or not it is shown,
+        so turning one off and on again gives back the same row.
+      properties:
+        id: { type: string }
+        remote_id: { type: string, description: "The id Google knows it by; an address for the primary calendar." }
+        name: { type: string }
+        colour:
+          type: string
+          description: >
+            Google's own hex value, not one of verdande's ten named colours. Those
+            are names so the interface can restyle them per theme and they are
+            verdande's palette; a Google calendar is told apart by the colour the
+            person already knows it by.
+        time_zone: { type: string }
+        primary: { type: boolean }
+        writable:
+          type: boolean
+          description: >
+            Whether the connected account could write to it. Nothing does — the
+            scope is read-only — and it is stored so the day something can, the
+            interface knows which calendars could even be offered.
+        shown: { type: boolean }
+
+    CalendarEvent:
+      type: object
+      description: >
+        One occurrence, in the shape a grid asks about. A recurrence is expanded by
+        Google into its occurrences, so what arrives here is a day, not a rule.
+      properties:
+        id: { type: string }
+        calendar_id: { type: string }
+        summary: { type: string }
+        starts_at:
+          type: string
+          description: >
+            RFC 3339 as Google wrote it, offset and all. Empty for an all-day
+            event, which has a day rather than a moment — inventing midnight for it
+            is how an event moves a day when a container moves time zone.
+        ends_at: { type: string }
+        start_day: { type: string, format: date }
+        end_day:
+          type: string
+          format: date
+          description: >
+            The last day the event covers, inclusive. Google's all-day end date is
+            exclusive and is corrected on the way in, once, rather than by every
+            reader.
+        all_day: { type: boolean }
+        location: { type: string }
+        url: { type: string, description: "Opens the event in Google's own interface." }
+        calendar_name: { type: string }
+        colour: { type: string }
+
+    Note:
+      type: object
+      description: A page of Markdown. The body is the stored form and the exported form.
+      properties:
+        id: { type: string }
+        project_id: { type: string }
+        title: { type: string, readOnly: true, description: "The note's first line. Derived on every save; it cannot be set." }
+        body: { type: string, description: Markdown }
+        pinned: { type: boolean }
+        created_at: { type: string, format: date-time }
+        updated_at: { type: string, format: date-time }
+        links:
+          type: array
+          description: What the body points at, read out of the text on the way in.
+          items:
+            type: object
+            properties:
+              kind: { type: string, enum: [task, note, project] }
+              target_id: { type: string }
+
+    NoteInput:
+      type: object
+      properties:
+        project_id: { type: string, description: "Empty files it under no project." }
+        body: { type: string, description: "Markdown. Its first line becomes the title." }
+        pinned: { type: boolean }
+
     Mailbox:
       type: object
       description: One connected mailbox. The password and any token are never returned.

internal/ai/ai.go

@@ -19,6 +19,8 @@ import (
 	"fmt"
 	"io"
 	"net/http"
+
+	"github.com/kristianwind/verdande/internal/safedial"
 	"strings"
 	"time"
 )
@@ -76,7 +78,16 @@ func New(cfg Config) *Client {
 		// Generous: a local model on modest hardware can take a while to produce
 		// its first token, and the alternative is a timeout that only ever fires
 		// for the people running their own.
-		http: &http.Client{Timeout: 120 * time.Second},
+		// safedial, not a plain client. `base_url` is typed into a field in the
+		// interface, so it is a user-supplied address — and a server that fetches a
+		// user-supplied address is a way to ask it to reach things the caller
+		// cannot: the panel next door, a database on the same bridge, the cloud
+		// metadata endpoint. On a homelab that is most of what is worth reaching.
+		//
+		// The check is on the resolved address rather than on the URL, because a
+		// name answers whatever its owner says — and can answer differently the
+		// second time, after a parse-time check has passed.
+		http: safedial.Client(120 * time.Second),
 	}
 }
 
@@ -268,11 +279,35 @@ func (c *Client) do(req *http.Request, out any) error {
 		// The provider's own message is included: for a local model it is usually
 		// the actual problem ("model not found"), and hiding it would leave the
 		// operator with nothing to go on.
-		return fmt.Errorf("ai: %s said %s: %s", req.URL.Host, resp.Status, truncate(string(raw), 300))
+		// The provider's body is no longer passed back to the caller.
+		//
+		// It was, and combined with a free-text base URL that made a working
+		// internal scanner: point it at a host, read the first three hundred bytes
+		// of whatever answered. The operator still needs the message — for a local
+		// model it is usually the actual problem — so it goes to the log, where it
+		// is available to the person running the instance and to nobody else.
+		return &upstreamError{Host: req.URL.Host, Status: resp.Status, Body: truncate(string(raw), 300)}
 	}
 	return json.Unmarshal(raw, out)
 }
 
+// upstreamError keeps the provider's own words for the log and away from the
+// response. Error() is what reaches a caller; Detail() is what is written down.
+type upstreamError struct {
+	Host   string
+	Status string
+	Body   string
+}
+
+func (e *upstreamError) Error() string {
+	return fmt.Sprintf("ai: %s said %s", e.Host, e.Status)
+}
+
+// Detail is the whole of it, for the instance's own error log.
+func (e *upstreamError) Detail() string {
+	return fmt.Sprintf("ai: %s said %s: %s", e.Host, e.Status, e.Body)
+}
+
 func truncate(s string, max int) string {
 	if len(s) <= max {
 		return s

internal/beacon/beacon.go

@@ -0,0 +1,139 @@
+// Package beacon answers one question for the project, and refuses to answer any
+// other: how many installations are out there.
+//
+// It sends two values once a day — an anonymous id the installation made up for
+// itself, and the version it is running — and nothing else. No IP is stored by
+// the collector, no hostname, no domain, no account, no usage. The payload is
+// small enough to be printed in full on the settings page, and it is, because a
+// promise about telemetry is worth exactly as much as the reader's ability to
+// check it.
+//
+// # On by default, and off in one click
+//
+// The alternative that was asked for first was mandatory, and the argument
+// against it is practical rather than principled: it cannot be enforced. The
+// domain can be blocked, the binary can be patched, and a fork removes it in its
+// first commit — so mandatory buys nothing over on-by-default, while costing the
+// trust the rest of this program works for. Secrets are sealed here, the key is
+// kept out of the database, and the backup page warns you what a copy contains.
+// Telemetry you are not allowed to refuse is the one sentence in that story that
+// does not fit.
+//
+// So: on by default, said plainly, one switch to turn it off. That collects
+// essentially the same number and leaves nobody feeling tricked.
+//
+// # Where this disagrees with the rest of the program
+//
+// `config.UpdateCheck` is off unless asked for, and its comment gives the reason:
+// "a self-hosted app that reaches out without being told to has broken the deal
+// its operator made by self-hosting." That is the same situation as this one, and
+// the two defaults do not agree.
+//
+// The disagreement is written down here rather than smoothed over, because it is
+// a real one and the reader deserves to see both halves. The case for treating
+// them differently is that the update check reveals an instance to a third party
+// (GitHub) and returns something the operator can act on, while this returns
+// nothing and goes to the project itself — and that a count nobody sends is a
+// count that does not exist, whereas an update nobody checks for is one you can
+// still go and look up. Whether that is a distinction or an excuse is a judgement
+// call, and it was made deliberately by the person whose instance this is.
+//
+// If it is ever decided the other way, the change is one word: the default in
+// `beaconSettings`. Nothing else in this package assumes which way it points.
+//
+// # What the collector can still see
+//
+// A request has a source address whether or not anybody writes it down. The
+// collector does not store or log it, and the code is arranged so that it never
+// reaches a function that could — but it passes through a reverse proxy and a
+// tunnel on the way, and those keep their own logs. Saying "we send no IP" would
+// be a half-truth; what is true is that nothing here records one.
+package beacon
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"regexp"
+	"time"
+)
+
+// DefaultCollector is where a fresh installation reports, unless it is told
+// otherwise. Somebody running their own fleet points it at their own instance;
+// the field is on the settings page for exactly that.
+const DefaultCollector = "https://verdande.yggdrasilpanel.com/api/v1/beacon"
+
+// Payload is the entire message. Two fields, and adding a third is a change to
+// what this program promises, not a change to a struct.
+type Payload struct {
+	InstanceID string `json:"instance_id"`
+	Version    string `json:"version"`
+}
+
+// InstanceID and Version are checked on the way in as well as written on the way
+// out, because the collector's endpoint is unauthenticated: anything that reaches
+// it is a stranger's bytes, and it should be able to store only the two shapes it
+// expects.
+var (
+	idShape      = regexp.MustCompile(`^[0-9a-fA-F-]{16,64}$`)
+	versionShape = regexp.MustCompile(`^v?[0-9]{1,4}(\.[0-9]{1,5}){0,3}(-[0-9A-Za-z.]{1,20})?$`)
+)
+
+// ValidID reports whether an id is the shape this program writes.
+func ValidID(s string) bool { return idShape.MatchString(s) }
+
+// ValidVersion allows a version number and the word this binary uses when it was
+// built outside a release.
+func ValidVersion(s string) bool { return s == "dev" || versionShape.MatchString(s) }
+
+// Send delivers one ping. It is deliberately dull: a short timeout, no retry, no
+// queue, and a failure that is returned rather than made anybody's problem.
+//
+// No retry, because the next pass is tomorrow and a missed day changes a count of
+// installations by nothing. A telemetry ping that retries is a telemetry ping
+// that can hammer somebody's server on the day it is down.
+func Send(ctx context.Context, client *http.Client, collector string, p Payload) error {
+	if !ValidID(p.InstanceID) {
+		return fmt.Errorf("beacon: refusing to send a malformed id")
+	}
+	// Versionen kontrolleres også her, ikke kun hos modtageren. Kommentaren ved
+	// mønstrene lovede begge veje, og gjorde det ikke — og en installation, der
+	// sender noget mærkeligt, skal opdage det hos sig selv frem for at være noget,
+	// en fremmed collector skal filtrere fra.
+	if !ValidVersion(p.Version) {
+		return fmt.Errorf("beacon: refusing to send a malformed version")
+	}
+	body, err := json.Marshal(p)
+	if err != nil {
+		return err
+	}
+
+	ctx, cancel := context.WithTimeout(ctx, 15*time.Second)
+	defer cancel()
+
+	req, err := http.NewRequestWithContext(ctx, http.MethodPost, collector, bytes.NewReader(body))
+	if err != nil {
+		return err
+	}
+	req.Header.Set("Content-Type", "application/json")
+	// A plain user agent with the version already in the payload. Nothing is
+	// learned from it that the body does not already say, and it makes the request
+	// legible in a log rather than anonymous-looking.
+	req.Header.Set("User-Agent", "verdande-beacon/1")
+
+	resp, err := client.Do(req)
+	if err != nil {
+		return err
+	}
+	defer resp.Body.Close()
+	// Read and discard, so the connection can be reused rather than dropped.
+	_, _ = io.Copy(io.Discard, io.LimitReader(resp.Body, 4<<10))
+
+	if resp.StatusCode >= 400 {
+		return fmt.Errorf("beacon: collector answered %d", resp.StatusCode)
+	}
+	return nil
+}

internal/beacon/beacon_test.go

@@ -0,0 +1,114 @@
+package beacon
+
+import (
+	"context"
+	"encoding/json"
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+)
+
+// Hvad der bliver sendt, tegn for tegn.
+//
+// Prøven er skrevet imod *hele* kroppen og ikke imod enkelte felter, fordi det er
+// den, der er løftet: siden siger "præcis det her og ikke mere", og et felt lagt
+// til senere skal vælte noget. En prøve, der kun så efter, at instance_id var med,
+// ville lade en ny nøgle glide igennem uden at nogen opdagede det.
+func TestSendsExactlyTwoFields(t *testing.T) {
+	var got map[string]any
+	var contentType string
+
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		contentType = r.Header.Get("Content-Type")
+		body, _ := io.ReadAll(r.Body)
+		if err := json.Unmarshal(body, &got); err != nil {
+			t.Errorf("kroppen er ikke JSON: %v", err)
+		}
+		w.WriteHeader(http.StatusNoContent)
+	}))
+	defer srv.Close()
+
+	err := Send(context.Background(), srv.Client(), srv.URL, Payload{
+		InstanceID: "01a01b16-4e54-7000-9eaa-2f8eb0629c3a",
+		Version:    "v0.26.3",
+	})
+	if err != nil {
+		t.Fatalf("Send: %v", err)
+	}
+
+	if contentType != "application/json" {
+		t.Errorf("Content-Type = %q", contentType)
+	}
+	if len(got) != 2 {
+		t.Fatalf("der blev sendt %d felter, ikke to: %v", len(got), got)
+	}
+	if got["instance_id"] != "01a01b16-4e54-7000-9eaa-2f8eb0629c3a" {
+		t.Errorf("instance_id = %v", got["instance_id"])
+	}
+	if got["version"] != "v0.26.3" {
+		t.Errorf("version = %v", got["version"])
+	}
+}
+
+// En collector, der er nede, er ikke denne installations problem.
+func TestSendReportsAFailureRatherThanRetrying(t *testing.T) {
+	calls := 0
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		calls++
+		w.WriteHeader(http.StatusInternalServerError)
+	}))
+	defer srv.Close()
+
+	err := Send(context.Background(), srv.Client(), srv.URL, Payload{
+		InstanceID: "01a01b16-4e54-7000-9eaa-2f8eb0629c3a", Version: "v1.0.0",
+	})
+	if err == nil {
+		t.Fatal("en 500 skal give en fejl")
+	}
+	if calls != 1 {
+		t.Errorf("der blev prøvet %d gange; en telemetri-ping må ikke hamre på en server, der er nede", calls)
+	}
+}
+
+// Et id, der ikke er id-formet, sendes slet ikke — så en fejl her ikke bliver til
+// noget, en fremmed collector skal filtrere fra.
+func TestSendRefusesAMalformedID(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		t.Error("der blev sendt noget, som ikke skulle sendes")
+	}))
+	defer srv.Close()
+
+	if err := Send(context.Background(), srv.Client(), srv.URL, Payload{
+		InstanceID: "; DROP TABLE beacon_installs", Version: "v1.0.0",
+	}); err == nil {
+		t.Fatal("et misformet id skal afvises før det forlader maskinen")
+	}
+}
+
+func TestShapes(t *testing.T) {
+	ok := []string{"01a01b16-4e54-7000-9eaa-2f8eb0629c3a", "89df44d7-3742-4611-9a43-db0b07733c6d"}
+	for _, s := range ok {
+		if !ValidID(s) {
+			t.Errorf("ValidID(%q) = false", s)
+		}
+	}
+	bad := []string{"", "kort", "../../etc/passwd", "01a01b16-4e54-7000-9eaa-2f8eb0629c3a'; --",
+		"<script>alert(1)</script>"}
+	for _, s := range bad {
+		if ValidID(s) {
+			t.Errorf("ValidID(%q) = true", s)
+		}
+	}
+
+	for _, s := range []string{"v0.26.3", "0.26.3", "v1.2.3-rc.1", "dev"} {
+		if !ValidVersion(s) {
+			t.Errorf("ValidVersion(%q) = false", s)
+		}
+	}
+	for _, s := range []string{"", "v<script>", "v" + string(make([]byte, 200))} {
+		if ValidVersion(s) {
+			t.Errorf("ValidVersion(%q) = true", s)
+		}
+	}
+}

internal/config/config.go

@@ -59,10 +59,19 @@ type Config struct {
 	// without spending the real one on every run.
 	GmailSyncBudget time.Duration
 
-	// GmailEndpoints redirects the Gmail calls at a server the tests control. Empty
-	// in production, where it means Google.
-	GmailTokenURL string
-	GmailAPIURL   string
+	// CalendarSyncBudget is the same bound for one calendar refresh, and exists for
+	// the same reason: a slow Google held the request open past what Cloudflare is
+	// willing to wait, and the browser got Cloudflare's HTML instead of an error
+	// this server could explain.
+	CalendarSyncBudget time.Duration
+
+	// Where Google is. Empty in production; a test points them at a server it
+	// controls, which is the only way to exercise a Google that is slow or refuses.
+	// The token endpoint is shared — Gmail and Calendar sign in through the same
+	// registration — and the two APIs are not.
+	GoogleTokenURL string
+	GmailAPIURL    string
+	CalendarAPIURL string
 
 	PanelURL      string
 	PanelToken    string
@@ -98,14 +107,15 @@ func Load() (*Config, error) {
 		TrashRetention: 30 * 24 * time.Hour,
 		Dev:            envBool("VERDANDE_DEV", false),
 
-		GmailClientID:     env("VERDANDE_GMAIL_CLIENT_ID", ""),
-		GmailSyncBudget:   25 * time.Second,
-		PanelURL:          strings.TrimSuffix(env("VERDANDE_PANEL_URL", ""), "/"),
-		PanelToken:        env("VERDANDE_PANEL_TOKEN", ""),
-		PanelServerID:     env("VERDANDE_PANEL_SERVER_ID", ""),
-		GmailClientSecret: env("VERDANDE_GMAIL_CLIENT_SECRET", ""),
-		SecretKey:         env("VERDANDE_SECRET_KEY", ""),
-		UpdateCheck:       envBool("VERDANDE_UPDATE_CHECK", false),
+		GmailClientID:      env("VERDANDE_GMAIL_CLIENT_ID", ""),
+		GmailSyncBudget:    25 * time.Second,
+		CalendarSyncBudget: 25 * time.Second,
+		PanelURL:           strings.TrimSuffix(env("VERDANDE_PANEL_URL", ""), "/"),
+		PanelToken:         env("VERDANDE_PANEL_TOKEN", ""),
+		PanelServerID:      env("VERDANDE_PANEL_SERVER_ID", ""),
+		GmailClientSecret:  env("VERDANDE_GMAIL_CLIENT_SECRET", ""),
+		SecretKey:          env("VERDANDE_SECRET_KEY", ""),
+		UpdateCheck:        envBool("VERDANDE_UPDATE_CHECK", false),
 	}
 
 	var err error
@@ -152,6 +162,15 @@ func (c *Config) BackupsDir() string { return filepath.Join(c.DataDir, "backups"
 // configured separately and left to drift out of step with it.
 func (c *Config) GmailRedirectURL() string { return c.BaseURL + "/oauth/gmail/callback" }
 
+// CalendarRedirectURL is a second registered URI rather than a reuse of Gmail's.
+//
+// One callback that decided from server-side state which of the two flows had come
+// back would save the operator one line in Google Cloud, and would put the choice
+// of *which token store to write* behind a lookup. When that goes wrong it goes
+// wrong by overwriting a working Gmail connection with calendar tokens — a failure
+// nobody would think to look for. Two paths cannot do that.
+func (c *Config) CalendarRedirectURL() string { return c.BaseURL + "/oauth/calendar/callback" }
+
 func env(key, def string) string {
 	if v, ok := os.LookupEnv(key); ok && v != "" {
 		return v

internal/filterquery/filterquery.go

@@ -60,6 +60,20 @@ func Parse(query string, ctx Context) (Compiled, error) {
 	if len(p.tokens) == 0 {
 		return Compiled{}, fmt.Errorf("filteret er tomt")
 	}
+	// Refused before it is parsed, not while.
+	//
+	// `combine` rebuilds the whole accumulated SQL string and re-copies the
+	// argument slice per operator, so the cost is quadratic in the number of
+	// terms: fifty thousand of them — three hundred kilobytes, which fits in a
+	// query string — took seven seconds of CPU and forty-six gigabytes of
+	// allocation in one request. The preview endpoint runs this on whatever is
+	// typed, and there is no write timeout on the server to cut it off.
+	//
+	// Two hundred terms is a filter nobody has ever written and far below where it
+	// costs anything.
+	if len(p.tokens) > maxTokens {
+		return Compiled{}, fmt.Errorf("filteret er for langt")
+	}
 
 	node, err := p.parseExpression()
 	if err != nil {
@@ -140,10 +154,19 @@ func isOperator(r rune) bool {
 
 // --- parser -------------------------------------------------------------------
 
+// The ceilings on one filter. See Parse for why.
+const (
+	maxTokens = 200
+	maxDepth  = 32
+)
+
 type parser struct {
 	tokens []token
 	pos    int
 	ctx    Context
+	// depth guards against a filter that is only parentheses. Each level is a
+	// stack frame, and nothing else stops somebody sending a megabyte of them.
+	depth int
 }
 
 func (p *parser) done() bool  { return p.pos >= len(p.tokens) }
@@ -187,6 +210,13 @@ func (p *parser) parseTerm() (Compiled, error) {
 	if p.done() {
 		return Compiled{}, fmt.Errorf("filteret slutter midt i et udtryk")
 	}
+	// Nesting is stack depth. A filter made of half a million opening parentheses
+	// is a megabyte of text and a stack frame for each.
+	p.depth++
+	defer func() { p.depth-- }()
+	if p.depth > maxDepth {
+		return Compiled{}, fmt.Errorf("filteret har for mange niveauer")
+	}
 
 	switch t := p.peek(); t.kind {
 	case tokNot:

internal/gcal/gcal.go

@@ -0,0 +1,339 @@
+// Package gcal reads a Google Calendar. It never writes one.
+//
+// The scope is calendar.readonly, and that is the whole of the decision: verdande
+// already is a CalDAV server, so a Google event shown here is a second calendar
+// laid over the first, not a copy Google and verdande now both have to agree
+// about. Writing needs `calendar.events`, and it needs an answer to what happens
+// when both sides moved the same meeting — which is a synchronisation model, not a
+// scope. Read first; write later and to one calendar at a time.
+//
+// What the API gives back and what this returns are deliberately different shapes.
+// Google answers with RFC 3339 instants for a timed event and bare dates for an
+// all-day one, and with an *exclusive* end date for the second. A calendar grid
+// asks one question — "which cells does this event cover" — so that is what an
+// Event answers, in days, worked out once here rather than in every caller.
+package gcal
+
+import (
+	"context"
+	"fmt"
+	"net/http"
+	"net/url"
+	"strings"
+	"time"
+
+	"github.com/kristianwind/verdande/internal/google"
+)
+
+// Scope is read-only, and only the calendar.
+//
+// Google also offers calendar.calendarlist.readonly and calendar.events.readonly,
+// which together are strictly less than this — they leave out access rules and
+// account settings, which verdande has no use for. They are the tighter pair and
+// worth moving to; they are also newer, and this one has been documented and
+// accepted unchanged for a decade. A consent screen that fails with `invalid_scope`
+// is not a place to be adventurous on somebody else's Google account.
+const Scope = "https://www.googleapis.com/auth/calendar.readonly"
+
+const defaultAPIBase = "https://www.googleapis.com/calendar/v3"
+
+// The OAuth flow, which is Google's rather than the calendar's — the same one
+// Gmail signs in through, asking for the scope above. Aliased so a caller reads
+// one package for one feature.
+type (
+	Config = google.Config
+	PKCE   = google.PKCE
+	Token  = google.Token
+)
+
+var NewPKCE = google.NewPKCE
+
+// ErrUnauthorized means the tokens are no longer good — access was revoked, or the
+// password changed. Re-exported so a caller need not know the flow lives elsewhere.
+var ErrUnauthorized = google.ErrUnauthorized
+
+type Client struct {
+	accessToken string
+	// base is where the Calendar API is. A field rather than a constant so a test
+	// can point it at a server it controls; empty is Google. There is no other way
+	// to exercise a calendar that is slow, empty, or refuses.
+	base string
+	http *http.Client
+}
+
+func NewClient(accessToken string) *Client {
+	return &Client{accessToken: accessToken, http: &http.Client{Timeout: 30 * time.Second}}
+}
+
+// At points the client at another server. Tests only; the zero value is Google.
+func (c *Client) At(base string) *Client {
+	c.base = base
+	return c
+}
+
+func (c *Client) api() string {
+	if c.base != "" {
+		return c.base
+	}
+	return defaultAPIBase
+}
+
+// Calendar is one entry in the person's calendar list.
+type Calendar struct {
+	ID string
+	// Name is the summary Google holds. A calendar somebody renamed for themselves
+	// carries summaryOverride instead, and that is the name they will look for.
+	Name string
+	// Colour is Google's own hex value for the calendar, which is what makes two
+	// calendars in one grid tellable apart. Their own colour rather than one picked
+	// here: it is the colour they already know the calendar by.
+	Colour   string
+	TimeZone string
+	Primary  bool
+	// Owner means the connected account can write to it. Nothing writes today —
+	// it is stored so the day something does, the interface knows which calendars
+	// could even be offered.
+	Owner bool
+}
+
+// Calendars lists what the connected account can see.
+func (c *Client) Calendars(ctx context.Context) ([]Calendar, error) {
+	var out []Calendar
+	page := ""
+	// Bounded rather than "until Google stops": a page token that never empties is
+	// a loop that never ends, and the difference between a bug at Google and a
+	// hung sync should not be this server hanging.
+	for range 10 {
+		v := url.Values{}
+		v.Set("minAccessRole", "reader")
+		v.Set("maxResults", "250")
+		if page != "" {
+			v.Set("pageToken", page)
+		}
+
+		var parsed struct {
+			Items []struct {
+				ID              string `json:"id"`
+				Summary         string `json:"summary"`
+				SummaryOverride string `json:"summaryOverride"`
+				BackgroundColor string `json:"backgroundColor"`
+				TimeZone        string `json:"timeZone"`
+				Primary         bool   `json:"primary"`
+				AccessRole      string `json:"accessRole"`
+				Deleted         bool   `json:"deleted"`
+			} `json:"items"`
+			NextPageToken string `json:"nextPageToken"`
+		}
+		if err := c.get(ctx, c.api()+"/users/me/calendarList?"+v.Encode(), &parsed); err != nil {
+			return nil, err
+		}
+
+		for _, item := range parsed.Items {
+			if item.Deleted {
+				continue
+			}
+			name := item.SummaryOverride
+			if name == "" {
+				name = item.Summary
+			}
+			out = append(out, Calendar{
+				ID: item.ID, Name: name, Colour: item.BackgroundColor,
+				TimeZone: item.TimeZone, Primary: item.Primary,
+				Owner: item.AccessRole == "owner" || item.AccessRole == "writer",
+			})
+		}
+		if parsed.NextPageToken == "" {
+			break
+		}
+		page = parsed.NextPageToken
+	}
+	return out, nil
+}
+
+// Event is one occurrence, in the shape a calendar grid asks about.
+type Event struct {
+	ID      string
+	Summary string
+	// StartsAt and EndsAt are RFC 3339 for a timed event and empty for an all-day
+	// one — an all-day event has no instant, only a day, and inventing midnight for
+	// it is how an event moves a day every time a server changes time zone.
+	StartsAt string
+	EndsAt   string
+	// StartDay and EndDay are the first and last day the event covers, inclusive at
+	// both ends. Google's all-day end date is exclusive; that is corrected here,
+	// once, rather than in every reader.
+	StartDay string
+	EndDay   string
+	AllDay   bool
+	Location string
+	// URL opens the event in Google's own interface. Same reasoning as the Gmail
+	// link on a task made from a mail: what verdande shows is a pointer to the
+	// event, not a second copy of it that somebody could try to edit.
+	URL string
+}
+
+// Events lists what falls inside a window, one calendar at a time.
+//
+// `singleEvents` expands a recurrence into its occurrences, which is the only form
+// a grid can draw: an RRULE is an instruction, and a Tuesday cell needs the Tuesday
+// it produced. It also means verdande does not have to grow a second recurrence
+// engine that agrees with Google's about Danish summer time.
+//
+// from and to are dates, inclusive. The window is the caller's business; this
+// turns it into the half-open interval Google wants.
+func (c *Client) Events(ctx context.Context, calendarID, from, to string) ([]Event, error) {
+	start, err := time.Parse(dateLayout, from)
+	if err != nil {
+		return nil, fmt.Errorf("gcal: from: %w", err)
+	}
+	end, err := time.Parse(dateLayout, to)
+	if err != nil {
+		return nil, fmt.Errorf("gcal: to: %w", err)
+	}
+
+	var out []Event
+	page := ""
+	for range 20 {
+		v := url.Values{}
+		v.Set("singleEvents", "true")
+		v.Set("orderBy", "startTime")
+		v.Set("maxResults", "2500")
+		// UTC, and a day of slack at each end. An event at 23:30 on the last day in
+		// Copenhagen is 21:30 UTC that day, but one at 00:30 on the first day is
+		// 22:30 UTC the day *before* — so a window cut exactly at the requested
+		// dates loses the events at both edges. The extra day is thrown away again
+		// by the day fields below, which are computed from the event's own offset.
+		v.Set("timeMin", start.AddDate(0, 0, -1).Format(time.RFC3339))
+		v.Set("timeMax", end.AddDate(0, 0, 2).Format(time.RFC3339))
+		if page != "" {
+			v.Set("pageToken", page)
+		}
+
+		var parsed struct {
+			Items         []rawEvent `json:"items"`
+			NextPageToken string     `json:"nextPageToken"`
+		}
+		url := c.api() + "/calendars/" + url.PathEscape(calendarID) + "/events?" + v.Encode()
+		if err := c.get(ctx, url, &parsed); err != nil {
+			return nil, err
+		}
+
+		for _, item := range parsed.Items {
+			// A cancelled occurrence of a recurring event still comes back, so that
+			// a client keeping its own copy knows to drop it. verdande replaces the
+			// window wholesale, so it only has to not add it.
+			if item.Status == "cancelled" {
+				continue
+			}
+			event, ok := item.event()
+			if !ok {
+				continue
+			}
+			if event.EndDay < from || event.StartDay > to {
+				continue // the slack above, thrown away
+			}
+			out = append(out, event)
+		}
+		if parsed.NextPageToken == "" {
+			break
+		}
+		page = parsed.NextPageToken
+	}
+	return out, nil
+}
+
+const dateLayout = "2006-01-02"
+
+type rawEvent struct {
+	ID       string `json:"id"`
+	Status   string `json:"status"`
+	Summary  string `json:"summary"`
+	Location string `json:"location"`
+	HTMLLink string `json:"htmlLink"`
+	Start    when   `json:"start"`
+	End      when   `json:"end"`
+}
+
+type when struct {
+	Date     string `json:"date"`
+	DateTime string `json:"dateTime"`
+}
+
+// event turns Google's two shapes into the one a grid can read.
+//
+// The second return is false for an event with neither a date nor a dateTime —
+// which Google does return, for an event somebody is still being asked about. It
+// belongs on no day, so there is no cell to draw it in.
+func (r rawEvent) event() (Event, bool) {
+	e := Event{
+		ID: r.ID, Summary: strings.TrimSpace(r.Summary),
+		Location: r.Location, URL: r.HTMLLink,
+	}
+	if e.Summary == "" {
+		// Google's own interface says this for an event with no title, and a blank
+		// chip in a grid reads as a rendering fault rather than as an empty title.
+		e.Summary = "(uden titel)"
+	}
+
+	switch {
+	case r.Start.Date != "":
+		e.AllDay = true
+		e.StartDay = r.Start.Date
+		// Google's all-day end is the day *after* the last one, so a one-day event
+		// ends tomorrow. Subtracting a day is what makes "covers this cell" a
+		// comparison rather than a special case at every call site.
+		e.EndDay = r.Start.Date
+		if day, err := time.Parse(dateLayout, r.End.Date); err == nil {
+			if last := day.AddDate(0, 0, -1); !last.Before(mustDay(r.Start.Date)) {
+				e.EndDay = last.Format(dateLayout)
+			}
+		}
+	case r.Start.DateTime != "":
+		e.StartsAt = r.Start.DateTime
+		e.EndsAt = r.End.DateTime
+		// The day is the date part of the timestamp Google returned, which carries
+		// the event's own offset. Parsing it into a time.Time and formatting it
+		// back would ask *this process* what day it is — and a container running in
+		// UTC would then move a 23:30 meeting in Copenhagen to the day before.
+		e.StartDay = dayOf(r.Start.DateTime)
+		e.EndDay = dayOf(r.End.DateTime)
+		if e.EndDay == "" {
+			e.EndDay = e.StartDay
+		}
+		// An event ending at midnight ends the evening before, as far as a grid is
+		// concerned. Without this, every meeting that runs to 24:00 puts a chip in
+		// the following day as well.
+		if e.EndDay > e.StartDay && strings.Contains(r.End.DateTime, "T00:00:00") {
+			if day, err := time.Parse(dateLayout, e.EndDay); err == nil {
+				e.EndDay = day.AddDate(0, 0, -1).Format(dateLayout)
+			}
+		}
+	default:
+		return Event{}, false
+	}
+	if e.EndDay < e.StartDay {
+		e.EndDay = e.StartDay
+	}
+	return e, true
+}
+
+// dayOf takes the date out of an RFC 3339 timestamp without interpreting it.
+func dayOf(stamp string) string {
+	if len(stamp) < len(dateLayout) {
+		return ""
+	}
+	day := stamp[:len(dateLayout)]
+	if _, err := time.Parse(dateLayout, day); err != nil {
+		return ""
+	}
+	return day
+}
+
+func mustDay(s string) time.Time {
+	day, _ := time.Parse(dateLayout, s)
+	return day
+}
+
+func (c *Client) get(ctx context.Context, url string, out any) error {
+	return google.Get(ctx, c.http, c.accessToken, url, out)
+}

internal/gcal/gcal_test.go

@@ -0,0 +1,255 @@
+package gcal
+
+import (
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+)
+
+// fakeGoogle answers the two calls this package makes, out of whatever the test
+// hands it. There is no other way to exercise this: the real Calendar needs an
+// account, a registered client and somebody's consent, and none of the three can be
+// had inside a test — so the shapes Google returns are written down here and the
+// parsing is checked against them.
+func fakeGoogle(t *testing.T, calendarList any, events map[string]any) *Client {
+	t.Helper()
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		switch {
+		case strings.HasPrefix(r.URL.Path, "/users/me/calendarList"):
+			_ = json.NewEncoder(w).Encode(calendarList)
+		case strings.HasPrefix(r.URL.Path, "/calendars/"):
+			id := strings.TrimSuffix(strings.TrimPrefix(r.URL.Path, "/calendars/"), "/events")
+			body, ok := events[id]
+			if !ok {
+				http.Error(w, `{"error":"not found"}`, http.StatusNotFound)
+				return
+			}
+			_ = json.NewEncoder(w).Encode(body)
+		default:
+			http.Error(w, "unexpected path "+r.URL.Path, http.StatusNotFound)
+		}
+	}))
+	t.Cleanup(srv.Close)
+	return NewClient("token").At(srv.URL)
+}
+
+func TestCalendarsPrefersTheNameThePersonGaveIt(t *testing.T) {
+	client := fakeGoogle(t, map[string]any{
+		"items": []map[string]any{
+			{"id": "primary", "summary": "[email protected]", "backgroundColor": "#3f51b5",
+				"timeZone": "Europe/Copenhagen", "primary": true, "accessRole": "owner"},
+			{"id": "fam", "summary": "Family", "summaryOverride": "Familien",
+				"backgroundColor": "#0b8043", "accessRole": "reader"},
+			// A calendar removed from the list still arrives, flagged.
+			{"id": "gone", "summary": "Væk", "deleted": true, "accessRole": "reader"},
+		},
+	}, nil)
+
+	got, err := client.Calendars(t.Context())
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(got) != 2 {
+		t.Fatalf("got %d calendars, want 2 — a deleted one is not one you can show", len(got))
+	}
+	if got[1].Name != "Familien" {
+		t.Errorf("name = %q; summaryOverride is the name the person will look for", got[1].Name)
+	}
+	if !got[0].Primary || !got[0].Owner {
+		t.Errorf("the primary calendar came back as %+v", got[0])
+	}
+	if got[1].Owner {
+		t.Error("a reader was reported as an owner; nothing may offer to write to it")
+	}
+	if got[0].Colour != "#3f51b5" {
+		t.Errorf("colour = %q; two calendars in one grid are told apart by it", got[0].Colour)
+	}
+}
+
+// The three shapes an event arrives in, and the one shape a grid can read.
+func TestEventsBecomeDaysAGridCanAskAbout(t *testing.T) {
+	client := fakeGoogle(t, nil, map[string]any{
+		"primary": map[string]any{
+			"items": []map[string]any{
+				{
+					"id": "timed", "summary": "Bestyrelsesmøde", "htmlLink": "https://cal/1",
+					"start": map[string]string{"dateTime": "2026-08-20T14:00:00+02:00"},
+					"end":   map[string]string{"dateTime": "2026-08-20T15:30:00+02:00"},
+				},
+				{
+					// All-day, one day. Google's end is the day after.
+					"id": "allday", "summary": "Fridag",
+					"start": map[string]string{"date": "2026-08-21"},
+					"end":   map[string]string{"date": "2026-08-22"},
+				},
+				{
+					// All-day, three days.
+					"id": "trip", "summary": "Aarhus",
+					"start": map[string]string{"date": "2026-08-24"},
+					"end":   map[string]string{"date": "2026-08-27"},
+				},
+				{
+					// Runs to midnight, which is the evening before as far as a
+					// grid is concerned.
+					"id": "late", "summary": "Nattevagt",
+					"start": map[string]string{"dateTime": "2026-08-22T20:00:00+02:00"},
+					"end":   map[string]string{"dateTime": "2026-08-23T00:00:00+02:00"},
+				},
+				{
+					// A cancelled occurrence of a recurring event.
+					"id": "off", "status": "cancelled", "summary": "Aflyst",
+					"start": map[string]string{"date": "2026-08-25"},
+					"end":   map[string]string{"date": "2026-08-26"},
+				},
+				{
+					// Neither a date nor a dateTime: belongs on no day at all.
+					"id": "nowhere", "summary": "Uden tid",
+				},
+			},
+		},
+	})
+
+	got, err := client.Events(t.Context(), "primary", "2026-08-01", "2026-08-31")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	byID := map[string]Event{}
+	for _, e := range got {
+		byID[e.ID] = e
+	}
+	if len(got) != 4 {
+		t.Fatalf("got %d events, want 4: %+v", len(got), got)
+	}
+	if _, ok := byID["off"]; ok {
+		t.Error("a cancelled occurrence was kept; it is an event that is not happening")
+	}
+	if _, ok := byID["nowhere"]; ok {
+		t.Error("an event with no time was kept; there is no cell to draw it in")
+	}
+
+	timed := byID["timed"]
+	if timed.AllDay || timed.StartDay != "2026-08-20" || timed.EndDay != "2026-08-20" {
+		t.Errorf("timed = %+v", timed)
+	}
+	if timed.StartsAt != "2026-08-20T14:00:00+02:00" {
+		t.Errorf("the instant was rewritten: %q", timed.StartsAt)
+	}
+
+	allday := byID["allday"]
+	if !allday.AllDay || allday.StartDay != "2026-08-21" || allday.EndDay != "2026-08-21" {
+		t.Errorf("allday = %+v; Google's end date is exclusive and has to be corrected here",
+			allday)
+	}
+	if allday.StartsAt != "" {
+		t.Errorf("an all-day event was given an instant: %q — it has a day, not a moment",
+			allday.StartsAt)
+	}
+
+	if trip := byID["trip"]; trip.StartDay != "2026-08-24" || trip.EndDay != "2026-08-26" {
+		t.Errorf("trip = %+v, want 24th to 26th inclusive", trip)
+	}
+	if late := byID["late"]; late.EndDay != "2026-08-22" {
+		t.Errorf("late ends on %q; an event running to midnight ends the evening before, "+
+			"or every one of them puts a chip in the following day", late.EndDay)
+	}
+}
+
+// An event with no title has to say so. A blank chip in a grid reads as a
+// rendering fault rather than as an empty title.
+func TestAnEventWithNoTitleStillSaysSomething(t *testing.T) {
+	client := fakeGoogle(t, nil, map[string]any{
+		"c": map[string]any{"items": []map[string]any{{
+			"id":    "x",
+			"start": map[string]string{"date": "2026-08-20"},
+			"end":   map[string]string{"date": "2026-08-21"},
+		}}},
+	})
+	got, err := client.Events(t.Context(), "c", "2026-08-01", "2026-08-31")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(got) != 1 || got[0].Summary == "" {
+		t.Fatalf("got %+v", got)
+	}
+}
+
+// The window is asked for with a day of slack at each end, because an event late
+// in the evening in Copenhagen is the next day in UTC. The slack must not leak
+// out: an event on the day before the window is not in the window.
+func TestTheSlackAtTheEdgesIsThrownAwayAgain(t *testing.T) {
+	client := fakeGoogle(t, nil, map[string]any{
+		"c": map[string]any{"items": []map[string]any{
+			{"id": "before", "summary": "For tidligt",
+				"start": map[string]string{"date": "2026-08-09"},
+				"end":   map[string]string{"date": "2026-08-10"}},
+			{"id": "inside", "summary": "Med",
+				"start": map[string]string{"date": "2026-08-10"},
+				"end":   map[string]string{"date": "2026-08-11"}},
+			{"id": "after", "summary": "For sent",
+				"start": map[string]string{"date": "2026-08-21"},
+				"end":   map[string]string{"date": "2026-08-22"}},
+		}},
+	})
+	got, err := client.Events(t.Context(), "c", "2026-08-10", "2026-08-20")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(got) != 1 || got[0].ID != "inside" {
+		t.Fatalf("got %+v, want only the one inside the window", got)
+	}
+}
+
+// A page token has to be followed, or a busy calendar silently shows its first
+// page and nothing else — which is a calendar that lies about a day being clear.
+func TestEveryPageIsRead(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		body := map[string]any{
+			"items": []map[string]any{{"id": "a", "summary": "Første",
+				"start": map[string]string{"date": "2026-08-11"},
+				"end":   map[string]string{"date": "2026-08-12"}}},
+			"nextPageToken": "more",
+		}
+		if r.URL.Query().Get("pageToken") == "more" {
+			body = map[string]any{"items": []map[string]any{{"id": "b", "summary": "Anden",
+				"start": map[string]string{"date": "2026-08-12"},
+				"end":   map[string]string{"date": "2026-08-13"}}}}
+		}
+		_ = json.NewEncoder(w).Encode(body)
+	}))
+	defer srv.Close()
+
+	got, err := NewClient("t").At(srv.URL).Events(t.Context(), "c", "2026-08-01", "2026-08-31")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(got) != 2 {
+		t.Fatalf("got %d events, want both pages: %+v", len(got), got)
+	}
+}
+
+// A 401 is not a failure to retry; it is a connection that has ended. Telling the
+// two apart is what stops a revoked account being polled every ten minutes for ever.
+func TestARefusedTokenIsItsOwnError(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		http.Error(w, `{"error":"invalid_credentials"}`, http.StatusUnauthorized)
+	}))
+	defer srv.Close()
+
+	_, err := NewClient("spent").At(srv.URL).Calendars(t.Context())
+	if err != ErrUnauthorized {
+		t.Fatalf("err = %v, want ErrUnauthorized", err)
+	}
+}
+
+// Read-only, and only the calendar. The consent screen is what somebody agrees to,
+// and a scope that quietly grew is a promise quietly broken.
+func TestTheScopeIsReadOnly(t *testing.T) {
+	if !strings.HasSuffix(Scope, "calendar.readonly") {
+		t.Errorf("scope = %q; nothing here writes a calendar", Scope)
+	}
+}

internal/gmail/gmail.go

@@ -1,5 +1,5 @@
-// Package gmail implements the OAuth2 authorisation-code flow with PKCE against
-// Google, and the small slice of the Gmail API verdande needs.
+// Package gmail is the small slice of the Gmail API verdande needs, and the scope
+// it asks for.
 //
 // The connection is one-way on purpose: a starred or labelled message becomes a
 // task, and nothing verdande does afterwards touches the mailbox. Unstarring the
@@ -9,200 +9,51 @@
 //
 // Scope is gmail.readonly. verdande never needs to send, modify or delete, and
 // asking for less is what makes the consent screen something a person can agree to.
+//
+// The OAuth flow itself moved to internal/google when Calendar needed the same one.
+// The names below are aliases so that every call site — and this package's own
+// tests — still read as Gmail's, which is what they are: one registration, one
+// flow, one scope each.
 package gmail
 
 import (
 	"context"
-	"crypto/rand"
-	"crypto/sha256"
-	"encoding/base64"
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"net/url"
 	"strings"
 	"time"
+
+	"github.com/kristianwind/verdande/internal/google"
 )
 
-const (
-	authEndpoint         = "https://accounts.google.com/o/oauth2/v2/auth"
-	defaultTokenEndpoint = "https://oauth2.googleapis.com/token"
-	defaultAPIBase       = "https://gmail.googleapis.com/gmail/v1"
+// Read-only, and only mail. Not profile, not contacts, not send.
+const Scope = "https://www.googleapis.com/auth/gmail.readonly"
 
-	// Read-only, and only mail. Not profile, not contacts, not send.
-	Scope = "https://www.googleapis.com/auth/gmail.readonly"
+const defaultAPIBase = "https://gmail.googleapis.com/gmail/v1"
+
+// The OAuth flow, which is Google's rather than Gmail's.
+type (
+	Config = google.Config
+	PKCE   = google.PKCE
+	Token  = google.Token
 )
 
-// Endpoints is where Google is.
-//
-// A field rather than a constant so a test can point it at a server it controls.
-// There is no other way to exercise what happens when Gmail is slow or refuses —
-// and "the sync comes back before whatever sits in front of this server gives up
-// on it" is exactly the kind of promise worth a test and impossible to make
-// against the real thing.
-//
-// The zero value is Google, so nothing outside a test has to know it exists.
-type Endpoints struct {
-	Token string
-	API   string
-}
-
-func (e Endpoints) token() string {
-	if e.Token != "" {
-		return e.Token
-	}
-	return defaultTokenEndpoint
-}
-
-func (e Endpoints) api() string {
-	if e.API != "" {
-		return e.API
-	}
-	return defaultAPIBase
-}
-
-// Config is the OAuth client the operator registered in Google Cloud. It belongs to
-// the instance rather than to a person: one registration, any number of users.
-type Config struct {
-	ClientID     string
-	ClientSecret string
-	RedirectURL  string
-	// Endpoints is Google unless a test says otherwise.
-	Endpoints Endpoints
-}
-
-func (c Config) Configured() bool {
-	return c.ClientID != "" && c.ClientSecret != "" && c.RedirectURL != ""
-}
-
-// PKCE is the proof-key pair for one authorisation attempt.
-//
-// PKCE on a server-side client is not strictly required — the client secret already
-// authenticates the token exchange — but it costs nothing and closes the window in
-// which an authorisation code intercepted from the redirect could be replayed
-// before verdande gets to it.
-type PKCE struct {
-	Verifier  string
-	Challenge string
-	State     string
-}
-
-func NewPKCE() (PKCE, error) {
-	verifier, err := randomString(64)
-	if err != nil {
-		return PKCE{}, err
-	}
-	state, err := randomString(32)
-	if err != nil {
-		return PKCE{}, err
-	}
-	sum := sha256.Sum256([]byte(verifier))
-	return PKCE{
-		Verifier:  verifier,
-		Challenge: base64.RawURLEncoding.EncodeToString(sum[:]),
-		State:     state,
-	}, nil
-}
-
-// AuthURL is where the browser is sent to ask the person for consent.
-func (c Config) AuthURL(p PKCE) string {
-	v := url.Values{}
-	v.Set("client_id", c.ClientID)
-	v.Set("redirect_uri", c.RedirectURL)
-	v.Set("response_type", "code")
-	v.Set("scope", Scope)
-	v.Set("state", p.State)
-	v.Set("code_challenge", p.Challenge)
-	v.Set("code_challenge_method", "S256")
-	// Without both of these Google returns no refresh token on a re-authorisation,
-	// and the connection silently stops working an hour later.
-	v.Set("access_type", "offline")
-	v.Set("prompt", "consent")
-	return authEndpoint + "?" + v.Encode()
-}
-
-type Token struct {
-	AccessToken  string
-	RefreshToken string
-	ExpiresAt    time.Time
-}
-
-// Exchange trades the authorisation code for tokens.
-func (c Config) Exchange(ctx context.Context, code string, p PKCE) (Token, error) {
-	form := url.Values{}
-	form.Set("code", code)
-	form.Set("client_id", c.ClientID)
-	form.Set("client_secret", c.ClientSecret)
-	form.Set("redirect_uri", c.RedirectURL)
-	form.Set("grant_type", "authorization_code")
-	form.Set("code_verifier", p.Verifier)
-
-	return c.token(ctx, form)
-}
-
-// Refresh gets a fresh access token. Google does not return a new refresh token
-// here, so the caller keeps the one it has.
-func (c Config) Refresh(ctx context.Context, refreshToken string) (Token, error) {
-	form := url.Values{}
-	form.Set("refresh_token", refreshToken)
-	form.Set("client_id", c.ClientID)
-	form.Set("client_secret", c.ClientSecret)
-	form.Set("grant_type", "refresh_token")
-
-	token, err := c.token(ctx, form)
-	if err != nil {
-		return Token{}, err
-	}
-	token.RefreshToken = refreshToken
-	return token, nil
-}
-
-func (c Config) token(ctx context.Context, form url.Values) (Token, error) {
-	req, err := http.NewRequestWithContext(ctx, http.MethodPost, c.Endpoints.token(),
-		strings.NewReader(form.Encode()))
-	if err != nil {
-		return Token{}, err
-	}
-	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
-
-	resp, err := (&http.Client{Timeout: 30 * time.Second}).Do(req)
-	if err != nil {
-		return Token{}, err
-	}
-	defer resp.Body.Close()
-
-	var parsed struct {
-		AccessToken      string `json:"access_token"`
-		RefreshToken     string `json:"refresh_token"`
-		ExpiresIn        int    `json:"expires_in"`
-		Error            string `json:"error"`
-		ErrorDescription string `json:"error_description"`
-	}
-	if err := json.NewDecoder(resp.Body).Decode(&parsed); err != nil {
-		return Token{}, fmt.Errorf("gmail: reading token response: %w", err)
-	}
-	if parsed.Error != "" {
-		return Token{}, fmt.Errorf("gmail: %s: %s", parsed.Error, parsed.ErrorDescription)
-	}
-	if resp.StatusCode != http.StatusOK || parsed.AccessToken == "" {
-		return Token{}, fmt.Errorf("gmail: token exchange failed with %s", resp.Status)
-	}
-
-	return Token{
-		AccessToken:  parsed.AccessToken,
-		RefreshToken: parsed.RefreshToken,
-		// A minute of slack, so a token that is about to expire is refreshed
-		// rather than used and rejected.
-		ExpiresAt: time.Now().Add(time.Duration(parsed.ExpiresIn-60) * time.Second),
-	}, nil
-}
+var (
+	NewPKCE         = google.NewPKCE
+	ErrUnauthorized = google.ErrUnauthorized
+)
 
 // --- the API ---------------------------------------------------------------------
 
 type Client struct {
 	accessToken string
-	endpoints   Endpoints
-	http        *http.Client
+	// base is where the Gmail API is. A field rather than a constant so a test can
+	// point it at a server it controls — and "the sync comes back before whatever
+	// sits in front of this server gives up on it" is exactly the kind of promise
+	// worth a test and impossible to make against the real thing. Empty is Google.
+	base string
+	http *http.Client
 }
 
 func NewClient(accessToken string) *Client {
@@ -210,11 +61,18 @@ func NewClient(accessToken string) *Client {
 }
 
 // At points the client at another server. Tests only; the zero value is Google.
-func (c *Client) At(e Endpoints) *Client {
-	c.endpoints = e
+func (c *Client) At(base string) *Client {
+	c.base = base
 	return c
 }
 
+func (c *Client) api() string {
+	if c.base != "" {
+		return c.base
+	}
+	return defaultAPIBase
+}
+
 // Message is the part of a Gmail message a task is made from.
 type Message struct {
 	ID       string
@@ -233,7 +91,7 @@ func (c *Client) Profile(ctx context.Context) (string, error) {
 	var parsed struct {
 		EmailAddress string `json:"emailAddress"`
 	}
-	if err := c.get(ctx, c.endpoints.api()+"/users/me/profile", &parsed); err != nil {
+	if err := c.get(ctx, c.api()+"/users/me/profile", &parsed); err != nil {
 		return "", err
 	}
 	return parsed.EmailAddress, nil
@@ -257,7 +115,7 @@ func (c *Client) List(ctx context.Context, query string, max int) ([]string, err
 			ID string `json:"id"`
 		} `json:"messages"`
 	}
-	if err := c.get(ctx, c.endpoints.api()+"/users/me/messages?"+v.Encode(), &parsed); err != nil {
+	if err := c.get(ctx, c.api()+"/users/me/messages?"+v.Encode(), &parsed); err != nil {
 		return nil, err
 	}
 
@@ -288,7 +146,7 @@ func (c *Client) Get(ctx context.Context, id string) (Message, error) {
 			} `json:"headers"`
 		} `json:"payload"`
 	}
-	if err := c.get(ctx, c.endpoints.api()+"/users/me/messages/"+url.PathEscape(id)+"?"+v.Encode(), &parsed); err != nil {
+	if err := c.get(ctx, c.api()+"/users/me/messages/"+url.PathEscape(id)+"?"+v.Encode(), &parsed); err != nil {
 		return Message{}, err
 	}
 
@@ -308,31 +166,9 @@ func (c *Client) Get(ctx context.Context, id string) (Message, error) {
 }
 
 func (c *Client) get(ctx context.Context, url string, out any) error {
-	req, err := http.NewRequestWithContext(ctx, http.MethodGet, url, nil)
-	if err != nil {
-		return err
-	}
-	req.Header.Set("Authorization", "Bearer "+c.accessToken)
-
-	resp, err := c.http.Do(req)
-	if err != nil {
-		return err
-	}
-	defer resp.Body.Close()
-
-	if resp.StatusCode == http.StatusUnauthorized {
-		return ErrUnauthorized
-	}
-	if resp.StatusCode != http.StatusOK {
-		return fmt.Errorf("gmail: %s", resp.Status)
-	}
-	return json.NewDecoder(resp.Body).Decode(out)
+	return google.Get(ctx, c.http, c.accessToken, url, out)
 }
 
-// ErrUnauthorized means the tokens are no longer good — the person revoked access,
-// or changed their password. The caller disconnects rather than retrying.
-var ErrUnauthorized = fmt.Errorf("gmail: authorisation was refused")
-
 // SenderName pulls "Anders Jensen" out of "Anders Jensen <[email protected]>",
 // falling back to the address when there is no display name.
 func SenderName(from string) string {
@@ -375,11 +211,3 @@ func Query(trigger, label string) string {
 	terms = append(terms, "newer_than:30d")
 	return strings.Join(terms, " ")
 }
-
-func randomString(n int) (string, error) {
-	b := make([]byte, n)
-	if _, err := rand.Read(b); err != nil {
-		return "", err
-	}
-	return base64.RawURLEncoding.EncodeToString(b)[:n], nil
-}

internal/gmail/gmail_test.go

@@ -1,113 +1,19 @@
 package gmail
 
 import (
-	"crypto/sha256"
-	"encoding/base64"
-	"net/url"
 	"strings"
 	"testing"
 )
 
-// The challenge has to be the SHA-256 of the verifier, base64url without padding.
-// Getting this wrong means Google refuses every exchange with a message that does
-// not say which end is at fault.
-func TestPKCEChallengeMatchesItsVerifier(t *testing.T) {
-	p, err := NewPKCE()
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	sum := sha256.Sum256([]byte(p.Verifier))
-	want := base64.RawURLEncoding.EncodeToString(sum[:])
-	if p.Challenge != want {
-		t.Errorf("challenge = %q, want %q", p.Challenge, want)
-	}
-
-	// RFC 7636 requires 43–128 characters, and no padding.
-	if n := len(p.Verifier); n < 43 || n > 128 {
-		t.Errorf("verifier is %d characters, outside the 43–128 the spec allows", n)
-	}
-	if strings.ContainsAny(p.Verifier, "=+/") {
-		t.Errorf("verifier %q contains characters that are not URL-safe", p.Verifier)
-	}
-	if p.State == "" {
-		t.Error("no state was generated")
-	}
-
-	// Two attempts must not share anything.
-	other, err := NewPKCE()
-	if err != nil {
-		t.Fatal(err)
-	}
-	if other.Verifier == p.Verifier || other.State == p.State {
-		t.Error("two authorisation attempts produced the same secrets")
-	}
-}
-
-func TestAuthURL(t *testing.T) {
-	cfg := Config{
-		ClientID:     "client-123",
-		ClientSecret: "secret",
-		RedirectURL:  "https://todo.example.dk/oauth/gmail/callback",
-	}
-	p, err := NewPKCE()
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	raw := cfg.AuthURL(p)
-	parsed, err := url.Parse(raw)
-	if err != nil {
-		t.Fatalf("the URL does not parse: %v", err)
-	}
-	q := parsed.Query()
-
-	checks := map[string]string{
-		"client_id":             cfg.ClientID,
-		"redirect_uri":          cfg.RedirectURL,
-		"response_type":         "code",
-		"scope":                 Scope,
-		"code_challenge":        p.Challenge,
-		"code_challenge_method": "S256",
-		"state":                 p.State,
-		// Without both of these Google returns no refresh token on a
-		// re-authorisation, and the connection dies silently an hour later.
-		"access_type": "offline",
-		"prompt":      "consent",
-	}
-	for key, want := range checks {
-		if got := q.Get(key); got != want {
-			t.Errorf("%s = %q, want %q", key, got, want)
-		}
-	}
-
-	// The verifier itself must never leave the server.
-	if strings.Contains(raw, p.Verifier) {
-		t.Error("the code verifier was put in the authorisation URL")
-	}
-	// Read-only, and only mail.
+// The scope is the one thing verdande chooses about the connection, and it is the
+// one the person reads on the consent screen. The flow itself is exercised in
+// internal/google; what belongs here is that Gmail still asks for read-only mail.
+func TestTheScopeIsReadOnlyMail(t *testing.T) {
 	if !strings.HasSuffix(Scope, "gmail.readonly") {
 		t.Errorf("scope = %q; verdande never needs to send or modify", Scope)
 	}
 }
 
-func TestConfigured(t *testing.T) {
-	full := Config{ClientID: "a", ClientSecret: "b", RedirectURL: "c"}
-	if !full.Configured() {
-		t.Error("a complete config is not reported as configured")
-	}
-	for _, partial := range []Config{
-		{},
-		{ClientID: "a"},
-		{ClientID: "a", ClientSecret: "b"},
-		{ClientSecret: "b", RedirectURL: "c"},
-	} {
-		if partial.Configured() {
-			t.Errorf("%+v was reported as configured", partial)
-		}
-	}
-}
-
 func TestQuery(t *testing.T) {
 	cases := []struct {
 		trigger, label string

internal/google/google.go

@@ -0,0 +1,224 @@
+// Package google implements the OAuth2 authorisation-code flow with PKCE against
+// Google.
+//
+// It was written inside internal/gmail, because Gmail was the only thing that
+// needed it. Calendar needs the same flow — the same endpoints, the same PKCE, the
+// same refresh — and the only thing that differs between them is one string: the
+// scope. A second copy would be a second place for "access_type=offline" to be
+// forgotten, which is the mistake that makes a connection die silently an hour
+// after it was made.
+//
+// What is *not* here is the API calls. Those differ completely, so gmail and gcal
+// keep their own clients and share only the way in.
+package google
+
+import (
+	"context"
+	"crypto/rand"
+	"crypto/sha256"
+	"encoding/base64"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/url"
+	"strings"
+	"time"
+)
+
+const (
+	authEndpoint         = "https://accounts.google.com/o/oauth2/v2/auth"
+	defaultTokenEndpoint = "https://oauth2.googleapis.com/token"
+)
+
+// Config is the OAuth client the operator registered in Google Cloud, plus the
+// scope one feature is asking for.
+//
+// The client belongs to the instance rather than to a person: one registration,
+// any number of users. The scope belongs to the feature: Gmail and Calendar sign
+// in through the same registration and ask for different things, and Google issues
+// a refresh token per authorisation — so connecting one does not disturb the other.
+type Config struct {
+	ClientID     string
+	ClientSecret string
+	RedirectURL  string
+	Scope        string
+
+	// TokenURL is where Google is. A field rather than a constant so a test can
+	// point it at a server it controls: there is no other way to exercise what
+	// happens when the token endpoint is slow or refuses. Empty is Google, so
+	// nothing outside a test has to know it exists.
+	TokenURL string
+}
+
+func (c Config) Configured() bool {
+	return c.ClientID != "" && c.ClientSecret != "" && c.RedirectURL != ""
+}
+
+func (c Config) tokenURL() string {
+	if c.TokenURL != "" {
+		return c.TokenURL
+	}
+	return defaultTokenEndpoint
+}
+
+// PKCE is the proof-key pair for one authorisation attempt.
+//
+// PKCE on a server-side client is not strictly required — the client secret already
+// authenticates the token exchange — but it costs nothing and closes the window in
+// which an authorisation code intercepted from the redirect could be replayed
+// before verdande gets to it.
+type PKCE struct {
+	Verifier  string
+	Challenge string
+	State     string
+}
+
+func NewPKCE() (PKCE, error) {
+	verifier, err := randomString(64)
+	if err != nil {
+		return PKCE{}, err
+	}
+	state, err := randomString(32)
+	if err != nil {
+		return PKCE{}, err
+	}
+	sum := sha256.Sum256([]byte(verifier))
+	return PKCE{
+		Verifier:  verifier,
+		Challenge: base64.RawURLEncoding.EncodeToString(sum[:]),
+		State:     state,
+	}, nil
+}
+
+// AuthURL is where the browser is sent to ask the person for consent.
+func (c Config) AuthURL(p PKCE) string {
+	v := url.Values{}
+	v.Set("client_id", c.ClientID)
+	v.Set("redirect_uri", c.RedirectURL)
+	v.Set("response_type", "code")
+	v.Set("scope", c.Scope)
+	v.Set("state", p.State)
+	v.Set("code_challenge", p.Challenge)
+	v.Set("code_challenge_method", "S256")
+	// Without both of these Google returns no refresh token on a re-authorisation,
+	// and the connection silently stops working an hour later.
+	v.Set("access_type", "offline")
+	v.Set("prompt", "consent")
+	return authEndpoint + "?" + v.Encode()
+}
+
+type Token struct {
+	AccessToken  string
+	RefreshToken string
+	ExpiresAt    time.Time
+}
+
+// Exchange trades the authorisation code for tokens.
+func (c Config) Exchange(ctx context.Context, code string, p PKCE) (Token, error) {
+	form := url.Values{}
+	form.Set("code", code)
+	form.Set("client_id", c.ClientID)
+	form.Set("client_secret", c.ClientSecret)
+	form.Set("redirect_uri", c.RedirectURL)
+	form.Set("grant_type", "authorization_code")
+	form.Set("code_verifier", p.Verifier)
+
+	return c.token(ctx, form)
+}
+
+// Refresh gets a fresh access token. Google does not return a new refresh token
+// here, so the caller keeps the one it has.
+func (c Config) Refresh(ctx context.Context, refreshToken string) (Token, error) {
+	form := url.Values{}
+	form.Set("refresh_token", refreshToken)
+	form.Set("client_id", c.ClientID)
+	form.Set("client_secret", c.ClientSecret)
+	form.Set("grant_type", "refresh_token")
+
+	token, err := c.token(ctx, form)
+	if err != nil {
+		return Token{}, err
+	}
+	token.RefreshToken = refreshToken
+	return token, nil
+}
+
+func (c Config) token(ctx context.Context, form url.Values) (Token, error) {
+	req, err := http.NewRequestWithContext(ctx, http.MethodPost, c.tokenURL(),
+		strings.NewReader(form.Encode()))
+	if err != nil {
+		return Token{}, err
+	}
+	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
+
+	resp, err := (&http.Client{Timeout: 30 * time.Second}).Do(req)
+	if err != nil {
+		return Token{}, err
+	}
+	defer resp.Body.Close()
+
+	var parsed struct {
+		AccessToken      string `json:"access_token"`
+		RefreshToken     string `json:"refresh_token"`
+		ExpiresIn        int    `json:"expires_in"`
+		Error            string `json:"error"`
+		ErrorDescription string `json:"error_description"`
+	}
+	if err := json.NewDecoder(resp.Body).Decode(&parsed); err != nil {
+		return Token{}, fmt.Errorf("google: reading token response: %w", err)
+	}
+	if parsed.Error != "" {
+		return Token{}, fmt.Errorf("google: %s: %s", parsed.Error, parsed.ErrorDescription)
+	}
+	if resp.StatusCode != http.StatusOK || parsed.AccessToken == "" {
+		return Token{}, fmt.Errorf("google: token exchange failed with %s", resp.Status)
+	}
+
+	return Token{
+		AccessToken:  parsed.AccessToken,
+		RefreshToken: parsed.RefreshToken,
+		// A minute of slack, so a token that is about to expire is refreshed
+		// rather than used and rejected.
+		ExpiresAt: time.Now().Add(time.Duration(parsed.ExpiresIn-60) * time.Second),
+	}, nil
+}
+
+// ErrUnauthorized means the tokens are no longer good — the person revoked access,
+// or changed their password. The caller disconnects rather than retrying.
+var ErrUnauthorized = fmt.Errorf("google: authorisation was refused")
+
+// Get performs an authorised GET and decodes the JSON body into out.
+//
+// Shared by the two API clients because the interesting part is the same in both:
+// a 401 is not a failure to retry, it is a connection that has ended, and telling
+// those apart is what stops a revoked account being polled every ten minutes for
+// ever.
+func Get(ctx context.Context, client *http.Client, accessToken, url string, out any) error {
+	req, err := http.NewRequestWithContext(ctx, http.MethodGet, url, nil)
+	if err != nil {
+		return err
+	}
+	req.Header.Set("Authorization", "Bearer "+accessToken)
+
+	resp, err := client.Do(req)
+	if err != nil {
+		return err
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode == http.StatusUnauthorized {
+		return ErrUnauthorized
+	}
+	if resp.StatusCode != http.StatusOK {
+		return fmt.Errorf("google: %s", resp.Status)
+	}
+	return json.NewDecoder(resp.Body).Decode(out)
+}
+
+func randomString(n int) (string, error) {
+	b := make([]byte, n)
+	if _, err := rand.Read(b); err != nil {
+		return "", err
+	}
+	return base64.RawURLEncoding.EncodeToString(b)[:n], nil
+}

internal/google/google_test.go

@@ -0,0 +1,127 @@
+package google
+
+import (
+	"crypto/sha256"
+	"encoding/base64"
+	"net/url"
+	"strings"
+	"testing"
+)
+
+// The challenge has to be the SHA-256 of the verifier, base64url without padding.
+// Getting this wrong means Google refuses every exchange with a message that does
+// not say which end is at fault.
+func TestPKCEChallengeMatchesItsVerifier(t *testing.T) {
+	p, err := NewPKCE()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	sum := sha256.Sum256([]byte(p.Verifier))
+	want := base64.RawURLEncoding.EncodeToString(sum[:])
+	if p.Challenge != want {
+		t.Errorf("challenge = %q, want %q", p.Challenge, want)
+	}
+
+	// RFC 7636 requires 43–128 characters, and no padding.
+	if n := len(p.Verifier); n < 43 || n > 128 {
+		t.Errorf("verifier is %d characters, outside the 43–128 the spec allows", n)
+	}
+	if strings.ContainsAny(p.Verifier, "=+/") {
+		t.Errorf("verifier %q contains characters that are not URL-safe", p.Verifier)
+	}
+	if p.State == "" {
+		t.Error("no state was generated")
+	}
+
+	// Two attempts must not share anything.
+	other, err := NewPKCE()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if other.Verifier == p.Verifier || other.State == p.State {
+		t.Error("two authorisation attempts produced the same secrets")
+	}
+}
+
+func TestAuthURL(t *testing.T) {
+	cfg := Config{
+		ClientID:     "client-123",
+		ClientSecret: "secret",
+		RedirectURL:  "https://todo.example.dk/oauth/gmail/callback",
+		Scope:        "https://www.googleapis.com/auth/gmail.readonly",
+	}
+	p, err := NewPKCE()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	raw := cfg.AuthURL(p)
+	parsed, err := url.Parse(raw)
+	if err != nil {
+		t.Fatalf("the URL does not parse: %v", err)
+	}
+	q := parsed.Query()
+
+	checks := map[string]string{
+		"client_id":             cfg.ClientID,
+		"redirect_uri":          cfg.RedirectURL,
+		"response_type":         "code",
+		"scope":                 cfg.Scope,
+		"code_challenge":        p.Challenge,
+		"code_challenge_method": "S256",
+		"state":                 p.State,
+		// Without both of these Google returns no refresh token on a
+		// re-authorisation, and the connection dies silently an hour later.
+		"access_type": "offline",
+		"prompt":      "consent",
+	}
+	for key, want := range checks {
+		if got := q.Get(key); got != want {
+			t.Errorf("%s = %q, want %q", key, got, want)
+		}
+	}
+
+	// The verifier itself must never leave the server.
+	if strings.Contains(raw, p.Verifier) {
+		t.Error("the code verifier was put in the authorisation URL")
+	}
+}
+
+// The scope is the one thing that differs between the two features signing in
+// through this, so it has to come out of the config rather than out of a constant
+// somebody could forget to change.
+func TestTheScopeComesFromTheConfig(t *testing.T) {
+	p, err := NewPKCE()
+	if err != nil {
+		t.Fatal(err)
+	}
+	calendar := "https://www.googleapis.com/auth/calendar.readonly"
+	raw := Config{ClientID: "a", Scope: calendar}.AuthURL(p)
+
+	parsed, err := url.Parse(raw)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if got := parsed.Query().Get("scope"); got != calendar {
+		t.Errorf("scope = %q, want %q — asking for the wrong one is a consent screen "+
+			"that grants the wrong thing", got, calendar)
+	}
+}
+
+func TestConfigured(t *testing.T) {
+	full := Config{ClientID: "a", ClientSecret: "b", RedirectURL: "c"}
+	if !full.Configured() {
+		t.Error("a complete config is not reported as configured")
+	}
+	for _, partial := range []Config{
+		{},
+		{ClientID: "a"},
+		{ClientID: "a", ClientSecret: "b"},
+		{ClientSecret: "b", RedirectURL: "c"},
+	} {
+		if partial.Configured() {
+			t.Errorf("%+v was reported as configured", partial)
+		}
+	}
+}

internal/httpapi/auth_handlers.go

@@ -32,6 +32,7 @@ type userJSON struct {
 	// about the work and not about the screen — the sidebar's width is the
 	// opposite case and stays in localStorage.
 	SidebarCollapsed []string `json:"sidebar_collapsed"`
+	NavOrder         []string `json:"nav_order"`
 	CreatedAt        string   `json:"created_at"`
 }
 
@@ -42,10 +43,14 @@ func toUserJSON(u *store.User) userJSON {
 	if collapsed == nil {
 		collapsed = []string{}
 	}
+	order := u.NavOrder
+	if order == nil {
+		order = []string{}
+	}
 	return userJSON{
 		ID: u.ID, Email: u.Email, Name: u.Name, AvatarColor: u.AvatarColor,
 		Timezone: u.Timezone, Locale: u.Locale, IsAdmin: u.IsAdmin,
-		TOTPEnabled: u.TOTPEnabled, SidebarCollapsed: collapsed,
+		TOTPEnabled: u.TOTPEnabled, SidebarCollapsed: collapsed, NavOrder: order,
 		CreatedAt: u.CreatedAt.Format(time.RFC3339),
 	}
 }
@@ -83,6 +88,30 @@ func (s *Server) handleSetSidebarSections(w http.ResponseWriter, r *http.Request
 	w.WriteHeader(http.StatusNoContent)
 }
 
+// handleSetNavOrder records the order of the fixed views in the sidebar.
+//
+// Its own route for the same reason as the folds: this writes on every drop, and
+// sharing the profile's path would make a reorder send a name and a timezone it
+// was never asked to change.
+func (s *Server) handleSetNavOrder(w http.ResponseWriter, r *http.Request) {
+	var req struct {
+		Order []string `json:"order"`
+	}
+	if err := decodeJSON(w, r, &req); err != nil {
+		return
+	}
+	if len(req.Order) > 20 {
+		writeError(w, http.StatusBadRequest, CodeBadRequest, "too many entries")
+		return
+	}
+	user := userFrom(r.Context())
+	if err := s.db.SetNavOrder(r.Context(), user.ID, req.Order); err != nil {
+		s.storeError(w, r, "set nav order", err)
+		return
+	}
+	w.WriteHeader(http.StatusNoContent)
+}
+
 // --- sign in -----------------------------------------------------------------
 
 type loginRequest struct {
@@ -125,7 +154,21 @@ func (s *Server) handleLogin(w http.ResponseWriter, r *http.Request) {
 		}
 	}
 
-	s.loginLimiter.reset(clientIP(r))
+	// The bucket is cleared only when the login is *finished*.
+	//
+	// It used to be cleared here, on the strength of the password alone — before
+	// the second factor had been asked for at all. That handed somebody who
+	// already had the password an unlimited supply of ten-guess batches: log in,
+	// get a fresh bucket and a fresh pending session, spend ten guesses on the
+	// code, log in again. At three valid codes in any moment and twenty requests a
+	// second, that is even odds inside an afternoon — against the one control that
+	// exists precisely for when the password is already gone.
+	//
+	// So an account with a second factor clears nothing yet. handleLoginTOTP does
+	// it, once the code is right.
+	if !user.TOTPEnabled {
+		s.loginLimiter.reset(clientIP(r))
+	}
 
 	// A session that still needs a code gets a short life of its own: long enough
 	// to fetch a phone, not long enough to be worth stealing.
@@ -162,6 +205,19 @@ func (s *Server) handleLoginTOTP(w http.ResponseWriter, r *http.Request) {
 	user := userFrom(r.Context())
 	session := sessionFrom(r.Context())
 
+	// Counted per account as well as per address.
+	//
+	// The address bucket alone is defeated by anybody with more than one, which is
+	// the ordinary case — a phone and a laptop is already two. A code is six
+	// digits: the only thing that makes it safe is that guesses are scarce, and
+	// scarcity has to be counted against the thing being attacked.
+	if ok, retry := s.totpLimiter.allow(user.ID); !ok {
+		w.Header().Set("Retry-After", retryAfterSeconds(retry))
+		writeError(w, http.StatusTooManyRequests, CodeRateLimited,
+			"too many verification codes; wait a moment and try again")
+		return
+	}
+
 	err := auth.VerifyTOTP(user.TOTPSecret, req.Code, time.Now())
 	if err != nil {
 		// A recovery code is accepted in the same field. Making somebody find a
@@ -169,6 +225,15 @@ func (s *Server) handleLoginTOTP(w http.ResponseWriter, r *http.Request) {
 		// introduce a second concept.
 		used, rerr := s.db.UseRecoveryCode(r.Context(), user.ID, req.Code)
 		if rerr != nil || !used {
+			// The pending session is left alive on purpose.
+			//
+			// Ending it on the first wrong digit was considered and rejected: it
+			// would make somebody who mistyped one number type their password again,
+			// and it buys almost nothing. What makes a six-digit code safe is that
+			// guesses are scarce, and the per-account bucket above is what makes
+			// them scarce — ten an hour, however many times the password is
+			// re-entered. The attack this closes was never "one session, many
+			// guesses"; it was "a fresh bucket for every password check".
 			writeError(w, http.StatusUnauthorized, CodeUnauthorized,
 				"that verification code is not valid")
 			return
@@ -176,6 +241,11 @@ func (s *Server) handleLoginTOTP(w http.ResponseWriter, r *http.Request) {
 		s.log.Info("recovery code used", "user", user.ID)
 	}
 
+	// Finished. Now the buckets may be cleared — both of them, so somebody who
+	// fumbled the code twice is not still waiting once they get it right.
+	s.loginLimiter.reset(clientIP(r))
+	s.totpLimiter.reset(user.ID)
+
 	if err := s.db.PromoteSession(r.Context(), session.ID, s.cfg.SessionTTL); err != nil {
 		s.internal(w, r, "promote session", err)
 		return

internal/httpapi/auth_test.go

@@ -27,6 +27,9 @@ type testServer struct {
 	*httptest.Server
 	db     *store.DB
 	client *http.Client
+	// api er den samme server, routeren hænger på. Et par prøver har brug for at
+	// nå ind i den — se `icsFetch` — og uden den her er der kun håndtaget udefra.
+	api *Server
 }
 
 func newTestServer(t *testing.T) *testServer {
@@ -62,7 +65,8 @@ func newTestServerWith(t *testing.T, configure func(*config.Config)) *testServer
 	// Discard: a passing test should print nothing, and these handlers log freely.
 	log := slog.New(slog.NewTextHandler(io.Discard, nil))
 
-	srv := httptest.NewServer(New(cfg, db, log, nil))
+	api := New(cfg, db, log, nil)
+	srv := httptest.NewServer(api)
 	t.Cleanup(srv.Close)
 
 	jar, err := cookiejar.New(nil)
@@ -75,6 +79,7 @@ func newTestServerWith(t *testing.T, configure func(*config.Config)) *testServer
 		// The cookie jar is what makes this a session test rather than a
 		// sequence of unrelated requests.
 		client: &http.Client{Jar: jar, Timeout: 10 * time.Second},
+		api:    api,
 	}
 }
 
@@ -301,7 +306,11 @@ func TestTOTPEnrolmentAndTwoStepLogin(t *testing.T) {
 
 	// Begin: a secret exists, but 2FA is not on yet — closing the tab here must
 	// not lock the account.
-	resp, body := ts.do(t, "POST", "/api/v1/auth/totp/setup", nil)
+	// Med adgangskoden: at slå andenfaktoren til er mindst lige så indgribende som
+	// at slå den fra, og den har altid spurgt.
+	resp, body := ts.do(t, "POST", "/api/v1/auth/totp/setup", map[string]string{
+		"password": "et langt kodeord",
+	})
 	if resp.StatusCode != http.StatusOK {
 		t.Fatalf("totp setup: %d %v", resp.StatusCode, body)
 	}
@@ -368,7 +377,9 @@ func TestRecoveryCodeCompletesLoginOnce(t *testing.T) {
 	ts := newTestServer(t)
 	ts.bootstrap(t)
 
-	_, body := ts.do(t, "POST", "/api/v1/auth/totp/setup", nil)
+	_, body := ts.do(t, "POST", "/api/v1/auth/totp/setup", map[string]string{
+		"password": "et langt kodeord",
+	})
 	secret := body["secret"].(string)
 	_, body = ts.do(t, "POST", "/api/v1/auth/totp/confirm", map[string]string{
 		"code": codeFor(t, secret),
@@ -897,3 +908,65 @@ func TestUserAgentsAreSummarisedForAPerson(t *testing.T) {
 		}
 	}
 }
+
+// Andenfaktoren kan ikke slås til uden adgangskoden.
+//
+// Døren åbnede før med et token og lukkede kun med et kodeord: `disable` har
+// altid spurgt, `setup` spurgte om ingenting. Et stjålet token kunne derfor hente
+// hemmeligheden, lægge den i sin egen godkender, bekræfte den og beholde den
+// eneste kopi af gendannelseskoderne — hvorefter ejerens næste login stoppede ved
+// en kode, de ikke havde, og de ikke kunne slå den fra uden at logge ind først.
+func TestTOTPCannotBeSwitchedOnWithoutThePassword(t *testing.T) {
+	ts := newTestServer(t)
+	ts.bootstrap(t)
+
+	resp, _ := ts.do(t, "POST", "/api/v1/auth/totp/setup", map[string]string{
+		"password": "det forkerte kodeord",
+	})
+	if resp.StatusCode != http.StatusUnprocessableEntity {
+		t.Fatalf("status %d, ventede at en forkert adgangskode blev afvist", resp.StatusCode)
+	}
+
+	resp, _ = ts.do(t, "POST", "/api/v1/auth/totp/setup", map[string]string{})
+	if resp.StatusCode == http.StatusOK {
+		t.Fatal("en tom adgangskode blev accepteret")
+	}
+}
+
+// Ratebegrænseren må ikke nulstilles af adgangskoden alene.
+//
+// Den blev det, og det gav én, der havde kodeordet, ubegrænsede portioner på ti
+// gæt: log ind, få en frisk spand og en frisk ventende session, brug ti gæt på
+// koden, log ind igen. Andenfaktoren findes præcis til det tilfælde, hvor
+// kodeordet allerede er tabt, så den portion skal betales for hver gang.
+func TestAPasswordAloneDoesNotRefillTheCodeAttempts(t *testing.T) {
+	ts := newTestServer(t)
+	ts.bootstrap(t)
+
+	_, body := ts.do(t, "POST", "/api/v1/auth/totp/setup", map[string]string{
+		"password": "et langt kodeord",
+	})
+	secret := body["secret"].(string)
+	ts.do(t, "POST", "/api/v1/auth/totp/confirm", map[string]string{"code": codeFor(t, secret)})
+	ts.do(t, "POST", "/api/v1/auth/logout", nil)
+
+	// Kodeordet er rigtigt hver gang; kun koden er forkert. Uden loftet ville det
+	// her kunne blive ved i det uendelige.
+	refused := 0
+	for i := 0; i < 14; i++ {
+		resp, _ := ts.do(t, "POST", "/api/v1/auth/login", map[string]string{
+			"email": "[email protected]", "password": "et langt kodeord",
+		})
+		if resp.StatusCode == http.StatusTooManyRequests {
+			refused++
+			continue
+		}
+		resp, _ = ts.do(t, "POST", "/api/v1/auth/login/totp", map[string]string{"code": "000000"})
+		if resp.StatusCode == http.StatusTooManyRequests {
+			refused++
+		}
+	}
+	if refused == 0 {
+		t.Fatal("fjorten runder med forkerte koder blev aldrig afvist; spanden fyldes stadig af adgangskoden")
+	}
+}

internal/httpapi/beacon_handlers.go

@@ -0,0 +1,297 @@
+package httpapi
+
+import (
+	"context"
+	"net/http"
+	"strings"
+	"time"
+
+	"github.com/kristianwind/verdande/internal/beacon"
+	"github.com/kristianwind/verdande/internal/safedial"
+	"github.com/kristianwind/verdande/internal/store"
+)
+
+// The beacon, from the instance's side.
+//
+// Two halves that happen to live in the same binary: the part that reports in,
+// which every installation runs, and the part that receives, which only the one
+// acting as collector turns on. See internal/beacon for what is sent and why it
+// is on by default rather than compulsory.
+
+const beaconScope = "beacon"
+
+// beaconConfig is what this instance has been told to do. The zero value is what
+// a fresh installation gets, which is why Enabled defaults to true elsewhere and
+// not here — a zero struct must never mean "silently on".
+type beaconConfig struct {
+	Enabled      bool   `json:"enabled"`
+	Collector    string `json:"collector_url"`
+	InstanceID   string `json:"instance_id"`
+	IsCollector  bool   `json:"is_collector"`
+	PublishCount bool   `json:"publish_count"`
+	LastPingAt   int64  `json:"last_ping_at,omitempty"`
+}
+
+// beaconSettings reads the configuration, filling in the defaults and minting the
+// anonymous id on first use.
+//
+// The id is generated here rather than derived from anything about the machine.
+// A hash of the hostname or the base URL would be stable and convenient and would
+// also be a value the collector could compare against a guess — which is the
+// difference between anonymous and pseudonymous, and it is the whole point.
+func (s *Server) beaconSettings(ctx context.Context) (beaconConfig, error) {
+	cfg := beaconConfig{Enabled: true, Collector: beacon.DefaultCollector}
+
+	stored, err := s.db.InstanceSettings(ctx, beaconScope)
+	if err != nil {
+		return cfg, err
+	}
+
+	if v, ok := stored["enabled"].(bool); ok {
+		cfg.Enabled = v
+	}
+	if v, ok := stored["collector_url"].(string); ok && strings.TrimSpace(v) != "" {
+		cfg.Collector = strings.TrimSpace(v)
+	}
+	if v, ok := stored["instance_id"].(string); ok && beacon.ValidID(v) {
+		cfg.InstanceID = v
+	}
+	if v, ok := stored["is_collector"].(bool); ok {
+		cfg.IsCollector = v
+	}
+	if v, ok := stored["publish_count"].(bool); ok {
+		cfg.PublishCount = v
+	}
+	if v, ok := stored["last_ping_at"].(float64); ok {
+		cfg.LastPingAt = int64(v)
+	}
+
+	if cfg.InstanceID == "" {
+		cfg.InstanceID = store.NewID()
+		if err := s.saveBeaconSettings(ctx, cfg); err != nil {
+			return cfg, err
+		}
+	}
+	return cfg, nil
+}
+
+func (s *Server) saveBeaconSettings(ctx context.Context, cfg beaconConfig) error {
+	return s.db.SetInstanceSettings(ctx, beaconScope, map[string]any{
+		"enabled":       cfg.Enabled,
+		"collector_url": cfg.Collector,
+		"instance_id":   cfg.InstanceID,
+		"is_collector":  cfg.IsCollector,
+		"publish_count": cfg.PublishCount,
+		"last_ping_at":  cfg.LastPingAt,
+	})
+}
+
+// --- what the settings page shows ------------------------------------------------
+
+type beaconStatusJSON struct {
+	Enabled      bool               `json:"enabled"`
+	Collector    string             `json:"collector_url"`
+	InstanceID   string             `json:"instance_id"`
+	Version      string             `json:"version"`
+	IsCollector  bool               `json:"is_collector"`
+	PublishCount bool               `json:"publish_count"`
+	LastPingAt   string             `json:"last_ping_at,omitempty"`
+	Stats        *store.BeaconStats `json:"stats,omitempty"`
+}
+
+func (s *Server) handleBeaconStatus(w http.ResponseWriter, r *http.Request) {
+	cfg, err := s.beaconSettings(r.Context())
+	if err != nil {
+		s.internal(w, r, "beacon settings", err)
+		return
+	}
+
+	out := beaconStatusJSON{
+		Enabled: cfg.Enabled, Collector: cfg.Collector, InstanceID: cfg.InstanceID,
+		Version: Version, IsCollector: cfg.IsCollector, PublishCount: cfg.PublishCount,
+	}
+	if cfg.LastPingAt > 0 {
+		out.LastPingAt = time.Unix(cfg.LastPingAt, 0).Format(time.RFC3339)
+	}
+	if cfg.IsCollector {
+		stats, err := s.db.BeaconSummary(r.Context())
+		if err != nil {
+			s.internal(w, r, "beacon summary", err)
+			return
+		}
+		out.Stats = &stats
+	}
+	writeJSON(w, http.StatusOK, out)
+}
+
+type beaconRequest struct {
+	Enabled      *bool   `json:"enabled"`
+	Collector    *string `json:"collector_url"`
+	IsCollector  *bool   `json:"is_collector"`
+	PublishCount *bool   `json:"publish_count"`
+}
+
+func (s *Server) handleSetBeacon(w http.ResponseWriter, r *http.Request) {
+	var req beaconRequest
+	if err := decodeJSON(w, r, &req); err != nil {
+		return
+	}
+	cfg, err := s.beaconSettings(r.Context())
+	if err != nil {
+		s.internal(w, r, "beacon settings", err)
+		return
+	}
+
+	if req.Enabled != nil {
+		cfg.Enabled = *req.Enabled
+	}
+	if req.IsCollector != nil {
+		cfg.IsCollector = *req.IsCollector
+	}
+	if req.PublishCount != nil {
+		cfg.PublishCount = *req.PublishCount
+	}
+	if req.Collector != nil {
+		url := strings.TrimSpace(*req.Collector)
+		if url == "" {
+			url = beacon.DefaultCollector
+		}
+		// http and https only, and said as a field error rather than a 500: an
+		// operator pointing this at their own collector will mistype it, and the
+		// page should say which field is wrong.
+		if !strings.HasPrefix(url, "http://") && !strings.HasPrefix(url, "https://") {
+			writeFieldErrors(w, map[string]string{"collector_url": "must start with http:// or https://"})
+			return
+		}
+		cfg.Collector = url
+	}
+
+	if err := s.saveBeaconSettings(r.Context(), cfg); err != nil {
+		s.internal(w, r, "save beacon settings", err)
+		return
+	}
+	s.handleBeaconStatus(w, r)
+}
+
+// --- the collector's side ---------------------------------------------------------
+
+// handleBeaconPing receives one report. Unauthenticated, because the whole point
+// is that a stranger's installation can reach it.
+//
+// Nothing about the request is recorded except the two values in the body. The
+// source address is not read here, and there is no code path from this function
+// to anything that could write one down — which is the only version of that
+// promise worth making.
+func (s *Server) handleBeaconPing(w http.ResponseWriter, r *http.Request) {
+	cfg, err := s.beaconSettings(r.Context())
+	if err != nil {
+		s.internal(w, r, "beacon settings", err)
+		return
+	}
+	// An instance that is not a collector does not quietly accept and drop pings —
+	// it says there is nothing here. Otherwise every installation in the world is a
+	// spam sink that answers 200 to anything.
+	if !cfg.IsCollector {
+		writeError(w, http.StatusNotFound, CodeNotFound, "this instance is not a beacon collector")
+		return
+	}
+
+	r.Body = http.MaxBytesReader(w, r.Body, 4<<10)
+	var p beacon.Payload
+	if err := decodeJSON(w, r, &p); err != nil {
+		return
+	}
+
+	// Checked, not trusted. This is the one endpoint anybody can post to, and the
+	// two columns behind it should only ever hold the two shapes this program
+	// writes — an id that is not id-shaped is somebody probing, not an install.
+	if !beacon.ValidID(p.InstanceID) {
+		writeFieldErrors(w, map[string]string{"instance_id": "malformed"})
+		return
+	}
+	if p.Version != "" && !beacon.ValidVersion(p.Version) {
+		writeFieldErrors(w, map[string]string{"version": "malformed"})
+		return
+	}
+
+	if err := s.db.RecordBeacon(r.Context(), p.InstanceID, p.Version); err != nil {
+		s.internal(w, r, "record beacon", err)
+		return
+	}
+	w.WriteHeader(http.StatusNoContent)
+}
+
+// handleBeaconCount publishes the number, when the collector has been told to.
+//
+// Thirty days rather than a running total: a total only climbs, so it stops
+// meaning "how many people use this" and starts meaning "how many ever tried it".
+func (s *Server) handleBeaconCount(w http.ResponseWriter, r *http.Request) {
+	cfg, err := s.beaconSettings(r.Context())
+	if err != nil {
+		s.internal(w, r, "beacon settings", err)
+		return
+	}
+	if !cfg.IsCollector || !cfg.PublishCount {
+		writeError(w, http.StatusNotFound, CodeNotFound, "not published")
+		return
+	}
+
+	n, err := s.db.BeaconCount(r.Context(), 30*24*time.Hour)
+	if err != nil {
+		s.internal(w, r, "beacon count", err)
+		return
+	}
+	w.Header().Set("Cache-Control", "public, max-age=60")
+	writeJSON(w, http.StatusOK, map[string]any{"installs": n, "window_days": 30})
+}
+
+// SendBeacon reports this installation, at most once a day.
+//
+// Exported and handed to the jobs runner the same way the mailbox syncs are: the
+// settings, the anonymous id and the version all live on this side, and the
+// runner should not have to know about any of them.
+//
+// The day is counted from the last successful send, not from a wall-clock hour.
+// A fleet of installations that all pinged at 03:00 would arrive in one spike;
+// counted this way they spread themselves out by when each was started.
+func (s *Server) SendBeacon(ctx context.Context) error {
+	cfg, err := s.beaconSettings(ctx)
+	if err != nil {
+		return err
+	}
+	if !cfg.Enabled {
+		return nil
+	}
+	// The collector does not report to itself over the network. It would work, and
+	// it would also mean the one instance whose count matters most depends on its
+	// own tunnel being up to be counted.
+	if cfg.IsCollector {
+		if err := s.db.RecordBeacon(ctx, cfg.InstanceID, Version); err != nil {
+			return err
+		}
+		cfg.LastPingAt = time.Now().Unix()
+		return s.saveBeaconSettings(ctx, cfg)
+	}
+
+	if time.Since(time.Unix(cfg.LastPingAt, 0)) < 24*time.Hour {
+		return nil
+	}
+
+	// safedial, ikke http.DefaultClient. Adressen kan skrives i fladen, og en
+	// administrator, der peger den på 127.0.0.1 eller på 169.254.169.254, ville
+	// ellers have en maskine, der henter indefra på kommando — og svaret på om den
+	// svarede, er i sig selv det, sådan et forsøg leder efter.
+	if err := beacon.Send(ctx, safedial.Client(15*time.Second), cfg.Collector, beacon.Payload{
+		InstanceID: cfg.InstanceID,
+		Version:    Version,
+	}); err != nil {
+		// Logged at info, not error. The collector being unreachable is not this
+		// installation's problem and must never look like one — it is somebody
+		// else's server, and the only consequence is a number being one lower.
+		s.log.Info("beacon not delivered", "err", err)
+		return nil
+	}
+
+	cfg.LastPingAt = time.Now().Unix()
+	return s.saveBeaconSettings(ctx, cfg)
+}

internal/httpapi/caldav_handlers.go

@@ -231,6 +231,33 @@ func (s *Server) handleCalDAVPut(w http.ResponseWriter, r *http.Request) {
 
 	existing, getErr := s.db.GetTask(r.Context(), taskID, user.ID)
 	if getErr == nil {
+		// The task decides, not the URL.
+		//
+		// The check above is about the project the *client named*, and a client
+		// names both halves of this address. Asking the project for permission and
+		// then taking the task id from the same string ties nothing together: a
+		// viewer on a shared project could name a project of their own — the Inbox,
+		// which everybody owns and may edit — and put the shared task's id in the
+		// filename. The project check passed on the Inbox and the write landed on a
+		// task they may only read.
+		//
+		// GetTask does not close it either: it answers "may this person see it",
+		// and a viewer may. `CanEdit` is the question, and it is the same one
+		// handleUpdateTask asks — the API door has always asked it.
+		role, err := store.TaskRole(r.Context(), s.db, taskID, user.ID)
+		if err != nil || !role.CanEdit() {
+			http.Error(w, "forbidden", http.StatusForbidden)
+			return
+		}
+		// And it has to live where the address says it does. Without this an editor
+		// on two projects can reach either through the other's URL — nothing is
+		// escalated by that on its own, but a URL allowed to lie about where a
+		// resource lives is how the case above got in.
+		if existing.ProjectID != projectID {
+			http.NotFound(w, r)
+			return
+		}
+
 		// An update. Only the fields a task client can express are touched;
 		// everything else the task carries stays as it is.
 		content := parsed.Summary

internal/httpapi/calendar_handlers.go

@@ -0,0 +1,808 @@
+package httpapi
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"io"
+	"net/http"
+	"strings"
+	"time"
+
+	"github.com/go-chi/chi/v5"
+
+	"github.com/kristianwind/verdande/internal/gcal"
+	"github.com/kristianwind/verdande/internal/ics"
+	"github.com/kristianwind/verdande/internal/safedial"
+	"github.com/kristianwind/verdande/internal/store"
+)
+
+// defaultCalendarSyncBudget bounds one "fetch now" when nothing else says
+// otherwise. Well under the hundred seconds a proxy is willing to wait, so this
+// server is the one that answers a slow Google rather than Cloudflare's own HTML
+// page — which is how a failure arrives with no code, no message and nothing in
+// the error log.
+const defaultCalendarSyncBudget = 25 * time.Second
+
+// The window verdande keeps a copy of.
+//
+// A month grid pages, so asking Google on every arrow press would mean a round trip
+// for a question answered ninety seconds ago — a calendar slower than the calendar
+// it is showing. A cached window is the alternative, and a window has to end
+// somewhere. Ninety days back is roughly "when was that", a year forward is past
+// anything anybody has booked; between them they cover every screen the grid can
+// reach without a person noticing an edge.
+//
+// The edge is still real, and the events endpoint says where it is rather than
+// answering an empty list for a month outside it. A calendar that quietly shows no
+// events is a calendar that lies about a day being clear.
+const (
+	calendarWindowBack   = 90
+	calendarWindowAhead  = 365
+	calendarDateLayout   = "2006-01-02"
+	calendarProviderName = "google"
+)
+
+func (s *Server) calendarClient(accessToken string) *gcal.Client {
+	return gcal.NewClient(accessToken).At(s.cfg.CalendarAPIURL)
+}
+
+// calendarConfig is the same registration Gmail signs in through, asking for a
+// different scope and coming back to a different URI.
+//
+// One OAuth client, two features. Google issues a refresh token per authorisation
+// and keeps up to a hundred of them live per account, each carrying the scopes it
+// was granted with — so connecting the calendar does not disturb a working Gmail,
+// and disconnecting one does not take the other with it.
+func (s *Server) calendarConfig(ctx context.Context) gcal.Config {
+	cfg := s.gmailConfig(ctx)
+	cfg.Scope = gcal.Scope
+	cfg.RedirectURL = s.cfg.CalendarRedirectURL()
+	return cfg
+}
+
+// --- connecting ------------------------------------------------------------------
+
+// handleCalendarAuthorize starts the flow. Same shape as Gmail's, and the same
+// reason for keeping the verifier server-side: the callback arrives as a top-level
+// navigation from Google, and a SameSite=Lax cookie is the kind of thing that works
+// until a browser tightens its defaults.
+func (s *Server) handleCalendarAuthorize(w http.ResponseWriter, r *http.Request) {
+	user := userFrom(r.Context())
+	cfg := s.calendarConfig(r.Context())
+
+	if !cfg.Configured() {
+		writeError(w, http.StatusConflict, CodeGmailNotConfigured,
+			"no Google OAuth client is registered on this server")
+		return
+	}
+
+	pkce, err := gcal.NewPKCE()
+	if err != nil {
+		s.internal(w, r, "calendar pkce", err)
+		return
+	}
+
+	// Its own settings scope, not Gmail's. Two handshakes in one row would mean a
+	// person who started both flows had one verifier, and whichever came back
+	// second would be refused for a reason nothing on the screen could explain.
+	settings, err := s.db.UserSettings(r.Context(), user.ID, "calendar")
+	if err != nil {
+		s.internal(w, r, "calendar settings", err)
+		return
+	}
+	settings["pkce_verifier"] = pkce.Verifier
+	settings["pkce_state"] = pkce.State
+	// The attempt expires: a stored verifier that lives forever is a replay window
+	// that lives forever.
+	settings["pkce_expires"] = time.Now().Add(10 * time.Minute).Unix()
+
+	if err := s.db.SetUserSettings(r.Context(), user.ID, "calendar", settings); err != nil {
+		s.internal(w, r, "calendar settings", err)
+		return
+	}
+	writeJSON(w, http.StatusOK, map[string]string{"url": cfg.AuthURL(pkce)})
+}
+
+// handleCalendarCallback is where Google sends the browser back.
+//
+// It answers with a redirect into the app rather than with JSON: the person is
+// looking at a browser tab, not at a fetch response.
+func (s *Server) handleCalendarCallback(w http.ResponseWriter, r *http.Request) {
+	user := userFrom(r.Context())
+	settingsURL := s.cfg.BaseURL + "/indstillinger/integrationer"
+
+	if errParam := r.URL.Query().Get("error"); errParam != "" {
+		// Somebody clicked "cancel" on the consent screen — or, on an Internal
+		// OAuth app, Google refused an account outside the organisation with
+		// `org_internal`. Both arrive here, and the page names what it was given.
+		http.Redirect(w, r, settingsURL+"?calendar="+errParam, http.StatusFound)
+		return
+	}
+
+	code := r.URL.Query().Get("code")
+	state := r.URL.Query().Get("state")
+	if code == "" || state == "" {
+		http.Redirect(w, r, settingsURL+"?calendar=invalid", http.StatusFound)
+		return
+	}
+
+	settings, err := s.db.UserSettings(r.Context(), user.ID, "calendar")
+	if err != nil {
+		s.internal(w, r, "calendar settings", err)
+		return
+	}
+	verifier, _ := settings["pkce_verifier"].(string)
+	expected, _ := settings["pkce_state"].(string)
+	expires, _ := settings["pkce_expires"].(float64)
+
+	// The state has to match, or this endpoint accepts a code from anywhere.
+	if verifier == "" || expected == "" || state != expected {
+		http.Redirect(w, r, settingsURL+"?calendar=state", http.StatusFound)
+		return
+	}
+	if int64(expires) < time.Now().Unix() {
+		http.Redirect(w, r, settingsURL+"?calendar=expired", http.StatusFound)
+		return
+	}
+
+	token, err := s.calendarConfig(r.Context()).Exchange(r.Context(), code,
+		gcal.PKCE{Verifier: verifier})
+	if err != nil {
+		s.log.Error("calendar exchange", "err", err, "user", user.ID)
+		http.Redirect(w, r, settingsURL+"?calendar=failed", http.StatusFound)
+		return
+	}
+	if token.RefreshToken == "" {
+		// Without one the connection dies in an hour. Google only withholds it when
+		// the consent prompt was skipped, which access_type and prompt are meant to
+		// prevent — so this means something is wrong with the client registration
+		// rather than with this request.
+		s.log.Error("calendar returned no refresh token", "user", user.ID)
+		http.Redirect(w, r, settingsURL+"?calendar=norefresh", http.StatusFound)
+		return
+	}
+
+	// The one-time values are cleared: keeping a spent verifier serves nothing and
+	// is one more secret at rest.
+	delete(settings, "pkce_verifier")
+	delete(settings, "pkce_state")
+	delete(settings, "pkce_expires")
+	if err := s.db.SetUserSettings(r.Context(), user.ID, "calendar", settings); err != nil {
+		s.internal(w, r, "clear calendar handshake", err)
+		return
+	}
+
+	account := &store.CalendarAccount{
+		UserID: user.ID, Provider: calendarProviderName,
+		RefreshToken: token.RefreshToken, AccessToken: token.AccessToken,
+		ExpiresAt: token.ExpiresAt,
+	}
+	if err := s.db.SaveCalendarAccount(r.Context(), account); err != nil {
+		s.internal(w, r, "save calendar tokens", err)
+		return
+	}
+
+	// The list of calendars, fetched now so the page that opens next has something
+	// to tick rather than an empty panel and a button. Best effort: an account that
+	// connects but cannot list itself is still connected, and the status endpoint
+	// asks again when it finds nothing.
+	if _, err := s.refreshCalendarList(r.Context(), account); err != nil {
+		s.log.Warn("calendar list", "err", err, "user", user.ID)
+	}
+
+	s.log.Info("calendar connected", "user", user.ID, "account", account.Account)
+	http.Redirect(w, r, settingsURL+"?calendar=connected", http.StatusFound)
+}
+
+// --- what the settings page reads --------------------------------------------------
+
+type calendarStatusJSON struct {
+	Connected bool             `json:"connected"`
+	Account   string           `json:"account,omitempty"`
+	Calendars []store.Calendar `json:"calendars"`
+	// RedirectURI is what has to be registered with Google, spelled out. Derived
+	// from VERDANDE_BASE_URL and matched exactly — the single most likely thing to
+	// be wrong, and the error Google gives for it names neither value.
+	RedirectURI string `json:"redirect_uri"`
+	// HasClient says whether there is an OAuth registration to connect through at
+	// all, so the page can explain rather than offer a button that answers 409.
+	HasClient  bool   `json:"has_client"`
+	LastSyncAt string `json:"last_sync_at,omitempty"`
+	// ReadOnly is stated rather than assumed. Nothing writes a Google calendar, and
+	// an interface that quietly looks editable is one somebody will try to edit.
+	ReadOnly bool `json:"read_only"`
+
+	// Abonnementer står ved siden af Google-kontoen og ikke inde i den: man kan
+	// have det ene uden det andet, og det er hele pointen med dem — en privat
+	// konto, der ikke kan bruge en Internal OAuth-klient, kan abonnere.
+	Subscriptions []store.CalendarAccount `json:"subscriptions"`
+}
+
+func (s *Server) handleGetCalendar(w http.ResponseWriter, r *http.Request) {
+	// Læst først, så de også kommer med, når der ingen Google-konto er.
+	subscriptions, err := s.db.Subscriptions(r.Context(), userFrom(r.Context()).ID)
+	if err != nil {
+		s.internal(w, r, "subscriptions", err)
+		return
+	}
+
+	user := userFrom(r.Context())
+
+	out := calendarStatusJSON{
+		Calendars:   []store.Calendar{},
+		RedirectURI: s.cfg.CalendarRedirectURL(),
+		HasClient:   s.calendarConfig(r.Context()).Configured(),
+		ReadOnly:    true,
+	}
+
+	account, err := s.db.CalendarAccountFor(r.Context(), user.ID, calendarProviderName)
+	if err != nil {
+		s.internal(w, r, "calendar account", err)
+		return
+	}
+	if account == nil || account.RefreshToken == "" {
+		out.Subscriptions = subscriptions
+		writeJSON(w, http.StatusOK, out)
+		return
+	}
+
+	out.Connected = true
+	out.Account = account.Account
+	if !account.LastSyncAt.IsZero() {
+		out.LastSyncAt = account.LastSyncAt.Format(time.RFC3339)
+	}
+
+	calendars, err := s.db.Calendars(r.Context(), account.ID)
+	if err != nil {
+		s.internal(w, r, "calendars", err)
+		return
+	}
+	// An account connected during a Google hiccup has no calendars and no way back:
+	// the person sees an empty list and nothing to press. Asking again here costs
+	// one request on a page nobody opens often, and means the wrong answer lasts
+	// until the next look rather than for ever. Same reasoning as the Gmail address.
+	if len(calendars) == 0 {
+		if fetched, err := s.refreshCalendarList(r.Context(), account); err == nil {
+			calendars = fetched
+			out.Account = account.Account
+		} else {
+			s.log.Warn("calendar list", "err", err, "user", user.ID)
+		}
+	}
+	if calendars != nil {
+		out.Calendars = calendars
+	}
+	out.Subscriptions = subscriptions
+	writeJSON(w, http.StatusOK, out)
+}
+
+type showCalendarsRequest struct {
+	// Shown is the whole set, not one flip. Same reasoning as the projects' order:
+	// a person has a handful of calendars, the question is "these ones", and a list
+	// that can only be built by several requests can land half applied.
+	Shown []string `json:"shown"`
+}
+
+func (s *Server) handleSetCalendars(w http.ResponseWriter, r *http.Request) {
+	var req showCalendarsRequest
+	if err := decodeJSON(w, r, &req); err != nil {
+		return
+	}
+	user := userFrom(r.Context())
+
+	account, err := s.db.CalendarAccountFor(r.Context(), user.ID, calendarProviderName)
+	if err != nil {
+		s.internal(w, r, "calendar account", err)
+		return
+	}
+	if account == nil {
+		// A 404 rather than a 409: everything the caller may not see answers 404,
+		// and "there is no such connection" is the true answer either way.
+		writeError(w, http.StatusNotFound, CodeNotFound, "no calendar is connected")
+		return
+	}
+	if err := s.db.ShowCalendars(r.Context(), account.ID, req.Shown); err != nil {
+		s.internal(w, r, "show calendars", err)
+		return
+	}
+	w.WriteHeader(http.StatusNoContent)
+}
+
+// handleDisconnectCalendar forgets the connection, and the copy of the calendars
+// with it. Unlike the tasks a mailbox made, none of this is the person's own work.
+func (s *Server) handleDisconnectCalendar(w http.ResponseWriter, r *http.Request) {
+	user := userFrom(r.Context())
+	account, err := s.db.CalendarAccountFor(r.Context(), user.ID, calendarProviderName)
+	if err != nil {
+		s.internal(w, r, "calendar account", err)
+		return
+	}
+	if account != nil {
+		if err := s.db.DeleteCalendarAccount(r.Context(), user.ID, account.ID); err != nil {
+			s.internal(w, r, "disconnect calendar", err)
+			return
+		}
+	}
+	w.WriteHeader(http.StatusNoContent)
+}
+
+// --- what the grid reads -----------------------------------------------------------
+
+type calendarEventsJSON struct {
+	Events []store.CalendarEvent `json:"events"`
+	// From and To are the window verdande holds a copy of, not the window that was
+	// asked for. A grid that has paged past it gets no events, and an empty answer
+	// with no explanation is a calendar quietly claiming a day is clear.
+	From string `json:"from"`
+	To   string `json:"to"`
+}
+
+func (s *Server) handleCalendarEvents(w http.ResponseWriter, r *http.Request) {
+	user := userFrom(r.Context())
+	from := r.URL.Query().Get("from")
+	to := r.URL.Query().Get("to")
+
+	fields := map[string]string{}
+	if !validDay(from) {
+		fields["from"] = "must be a date, as 2026-08-20"
+	}
+	if !validDay(to) {
+		fields["to"] = "must be a date, as 2026-08-20"
+	}
+	if len(fields) > 0 {
+		writeFieldErrors(w, fields)
+		return
+	}
+
+	events, err := s.db.CalendarEvents(r.Context(), user.ID, from, to)
+	if err != nil {
+		s.internal(w, r, "calendar events", err)
+		return
+	}
+	if events == nil {
+		events = []store.CalendarEvent{}
+	}
+	windowFrom, windowTo := calendarWindow(time.Now())
+	writeJSON(w, http.StatusOK, calendarEventsJSON{
+		Events: events, From: windowFrom, To: windowTo,
+	})
+}
+
+// handleCalendarSyncNow refreshes immediately, so somebody who has just connected
+// can see it work rather than wondering whether it did.
+func (s *Server) handleCalendarSyncNow(w http.ResponseWriter, r *http.Request) {
+	user := userFrom(r.Context())
+
+	// A budget of its own, well under what sits in front of this server. An unset
+	// budget is not a budget of nothing: a zero here would expire the context
+	// before the first call and make every sync a silent no-op.
+	budget := s.cfg.CalendarSyncBudget
+	if budget <= 0 {
+		budget = defaultCalendarSyncBudget
+	}
+	ctx, cancel := context.WithTimeout(r.Context(), budget)
+	defer cancel()
+
+	count, err := s.SyncCalendars(ctx, user)
+	if err != nil {
+		if errors.Is(err, context.DeadlineExceeded) {
+			// Not a failure: Google is slow or busy, some calendars were read, and
+			// the rest arrive on the next run. Every calendar is committed as it is
+			// read, so a short budget is a shorter run rather than a lost one.
+			writeJSON(w, http.StatusOK, map[string]any{"events": count, "partial": true})
+			return
+		}
+		s.upstream(w, r, CodeCalendarFailed, "sync calendar", err)
+		return
+	}
+	writeJSON(w, http.StatusOK, map[string]int{"events": count})
+}
+
+// SyncCalendars refreshes every calendar this person has chosen to see.
+//
+// Returns how many events were written. Also used by the background job, which is
+// why it takes a context and a user rather than a request.
+func (s *Server) SyncCalendars(ctx context.Context, user *store.User) (int, error) {
+	// Abonnementer først, og deres fejl tæller ikke mod Google.
+	//
+	// De to har intet med hinanden at gøre ud over at ende samme sted: et
+	// abonnement er en adresse, der hentes, hvor Google er et token, der udløber.
+	// En kalender, hvis vært er nede, må ikke få det til at se ud som om
+	// Google-forbindelsen er væk — og omvendt.
+	written, err := s.syncSubscriptions(ctx, user)
+	if err != nil {
+		s.log.Warn("calendar subscriptions", "err", err, "user", user.ID)
+	}
+
+	account, err := s.db.CalendarAccountFor(ctx, user.ID, calendarProviderName)
+	if err != nil {
+		return written, err
+	}
+	if account == nil || account.RefreshToken == "" {
+		return written, nil // not connected; nothing to do and nothing to complain about
+	}
+
+	// The same guard the mailboxes have, for the same reason: a press of "fetch
+	// now" during the sweep would otherwise have two runs replacing the same window
+	// at once, and the loser's delete would land after the winner's insert.
+	unlock := s.lockSync("calendar:" + account.ID)
+	defer unlock()
+	if fresh, err := s.db.CalendarAccountFor(ctx, user.ID, calendarProviderName); err == nil && fresh != nil {
+		account = fresh
+	}
+
+	access, err := s.calendarAccessToken(ctx, account)
+	if err != nil {
+		return 0, err
+	}
+	client := s.calendarClient(access)
+
+	// The list first, so a calendar added or renamed since the last run is drawn
+	// under its new name and one that has gone stops being drawn at all.
+	calendars, err := s.calendarList(ctx, client, account)
+	if err != nil {
+		return 0, s.forgetIfRevoked(ctx, user, account, err)
+	}
+
+	from, to := calendarWindow(time.Now())
+	for _, calendar := range calendars {
+		if !calendar.Shown {
+			continue
+		}
+		// A spent budget ends the run rather than turning into a failed fetch per
+		// calendar, logged one at a time.
+		if ctx.Err() != nil {
+			return written, ctx.Err()
+		}
+		events, err := client.Events(ctx, calendar.RemoteID, from, to)
+		if err != nil {
+			if errors.Is(err, gcal.ErrUnauthorized) {
+				return written, s.forgetIfRevoked(ctx, user, account, err)
+			}
+			// One calendar somebody was unshared from must not stop the others.
+			s.log.Warn("calendar events", "err", err, "calendar", calendar.Name)
+			continue
+		}
+
+		rows := make([]store.CalendarEvent, 0, len(events))
+		for _, e := range events {
+			rows = append(rows, store.CalendarEvent{
+				RemoteID: e.ID, Summary: e.Summary,
+				StartsAt: e.StartsAt, EndsAt: e.EndsAt,
+				StartDay: e.StartDay, EndDay: e.EndDay,
+				AllDay: e.AllDay, Location: e.Location, URL: e.URL,
+			})
+		}
+		if err := s.db.ReplaceCalendarEvents(ctx, calendar.ID, from, to, rows); err != nil {
+			return written, err
+		}
+		written += len(rows)
+	}
+
+	if err := s.db.MarkCalendarSynced(ctx, account.ID, time.Now()); err != nil {
+		return written, err
+	}
+	return written, nil
+}
+
+// calendarAccessToken returns a usable access token, refreshing only when the one
+// held has actually expired.
+func (s *Server) calendarAccessToken(ctx context.Context, account *store.CalendarAccount) (string, error) {
+	if account.AccessToken != "" && account.ExpiresAt.After(time.Now()) {
+		return account.AccessToken, nil
+	}
+	token, err := s.calendarConfig(ctx).Refresh(ctx, account.RefreshToken)
+	if err != nil {
+		return "", err
+	}
+	account.AccessToken = token.AccessToken
+	account.ExpiresAt = token.ExpiresAt
+	if err := s.db.SaveCalendarAccount(ctx, account); err != nil {
+		return "", err
+	}
+	return account.AccessToken, nil
+}
+
+// refreshCalendarList fetches the calendar list with a token it obtains itself.
+// Used by the paths that have an account but no client yet — connecting, and the
+// status endpoint correcting an empty list.
+func (s *Server) refreshCalendarList(ctx context.Context, account *store.CalendarAccount) ([]store.Calendar, error) {
+	access, err := s.calendarAccessToken(ctx, account)
+	if err != nil {
+		return nil, err
+	}
+	return s.calendarList(ctx, s.calendarClient(access), account)
+}
+
+// calendarList writes what the provider says and returns what is stored, which is
+// not the same list: the provider says what exists, and only verdande knows which
+// of them somebody chose to look at.
+func (s *Server) calendarList(ctx context.Context, client *gcal.Client, account *store.CalendarAccount) ([]store.Calendar, error) {
+	remote, err := client.Calendars(ctx)
+	if err != nil {
+		return nil, err
+	}
+
+	list := make([]store.Calendar, 0, len(remote))
+	for _, c := range remote {
+		list = append(list, store.Calendar{
+			RemoteID: c.ID, Name: c.Name, Colour: c.Colour,
+			TimeZone: c.TimeZone, Primary: c.Primary, Writable: c.Owner,
+		})
+		// The primary calendar is the account, and its id is the address. It is the
+		// only place the connected account names itself without a second scope —
+		// asking for a profile scope to learn an address already in the answer would
+		// be one more thing on the consent screen for nothing.
+		if c.Primary && account.Account == "" {
+			account.Account = c.ID
+			if err := s.db.SaveCalendarAccount(ctx, account); err != nil {
+				return nil, err
+			}
+		}
+	}
+	if err := s.db.ReplaceCalendars(ctx, account.ID, list); err != nil {
+		return nil, err
+	}
+	return s.db.Calendars(ctx, account.ID)
+}
+
+// forgetIfRevoked disconnects when Google says the grant is gone, and passes every
+// other failure through untouched.
+//
+// The distinction is the point. A revoked account polled every ten minutes for ever
+// is a log line a week long and a connection the person believes they removed; a
+// Google that is merely down is one that will answer next time.
+func (s *Server) forgetIfRevoked(ctx context.Context, user *store.User, account *store.CalendarAccount, err error) error {
+	if errors.Is(err, gcal.ErrUnauthorized) {
+		s.log.Info("calendar access was revoked; disconnecting", "user", user.ID)
+		_ = s.db.DeleteCalendarAccount(ctx, user.ID, account.ID)
+	}
+	return err
+}
+
+// calendarWindow is the span verdande keeps a copy of, measured from today.
+//
+// Built from the calendar date rather than by truncating the instant: Truncate
+// rounds against the Unix epoch, which is midnight UTC, and in Copenhagen that is
+// two in the morning — so for two hours of every summer day the window would start
+// and end a day out.
+func calendarWindow(now time.Time) (string, string) {
+	day := time.Date(now.Year(), now.Month(), now.Day(), 0, 0, 0, 0, now.Location())
+	return day.AddDate(0, 0, -calendarWindowBack).Format(calendarDateLayout),
+		day.AddDate(0, 0, calendarWindowAhead).Format(calendarDateLayout)
+}
+
+func validDay(s string) bool {
+	_, err := time.Parse(calendarDateLayout, s)
+	return err == nil
+}
+
+// --- abonnementer -----------------------------------------------------------------
+
+// maxICSBytes bounds one fetch. A published calendar of a decade of holidays is a
+// few hundred kilobytes; ten megabytes is not a calendar, and reading it into
+// memory on a schedule with nobody watching is how a homelab instance falls over
+// at three in the morning.
+const maxICSBytes = 10 << 20
+
+// normaliseCalendarURL turns what somebody pastes into something that can be
+// fetched.
+//
+// `webcal://` is not a scheme anything speaks. It is a convention — the same URL
+// over https, with a scheme that makes a desktop hand it to the calendar app
+// instead of the browser — and every publisher writes their links that way. A
+// person pasting one has pasted the right address; refusing it would be refusing
+// them on a technicality.
+func normaliseCalendarURL(raw string) (string, error) {
+	raw = strings.TrimSpace(raw)
+	if after, ok := strings.CutPrefix(raw, "webcal://"); ok {
+		raw = "https://" + after
+	}
+	if !strings.HasPrefix(raw, "https://") && !strings.HasPrefix(raw, "http://") {
+		return "", errors.New("must be an https:// or webcal:// address")
+	}
+	// The same wall the AI provider's base_url goes through, and for the same
+	// reason: this is an address a user typed, and the server is about to fetch it
+	// on a schedule of their choosing.
+	if reason := safedial.CheckURL(raw); reason != "" {
+		return "", errors.New(reason)
+	}
+	return raw, nil
+}
+
+// icsClient is the client a subscribed calendar is fetched with.
+//
+// safedial, checked on the *resolved* address at connect time and on every
+// redirect hop — because a name that passed the check when it was pasted can
+// answer 127.0.0.1 when the sweep runs at three in the morning.
+//
+// The field exists so a test can put an ordinary client here: httptest listens on
+// loopback, which is exactly what this refuses, so a test of the *format* cannot
+// otherwise reach its own server. It is never set outside a test, and the wall it
+// bypasses is tested where it belongs — `normaliseCalendarURL` refuses a private
+// address where it is written down, and `internal/push` proves the connect-time
+// half.
+func (s *Server) icsClient() *http.Client {
+	if s.icsFetch != nil {
+		return s.icsFetch
+	}
+	return safedial.Client(30 * time.Second)
+}
+
+// fetchICS reads a subscribed calendar.
+//
+// safedial, not a plain client — checked on the resolved address at connect time
+// and on every redirect hop, because a name that passed the check when it was
+// pasted can answer 127.0.0.1 when the sweep runs at three in the morning.
+func (s *Server) fetchICS(ctx context.Context, url string) (ics.Subscribed, error) {
+	req, err := http.NewRequestWithContext(ctx, http.MethodGet, url, nil)
+	if err != nil {
+		return ics.Subscribed{}, err
+	}
+	req.Header.Set("Accept", "text/calendar, text/plain;q=0.9, */*;q=0.5")
+	req.Header.Set("User-Agent", "verdande/"+Version)
+
+	resp, err := s.icsClient().Do(req)
+	if err != nil {
+		return ics.Subscribed{}, err
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode >= 300 {
+		return ics.Subscribed{}, fmt.Errorf("%s said %s", resp.Request.URL.Host, resp.Status)
+	}
+
+	body, err := io.ReadAll(io.LimitReader(resp.Body, maxICSBytes+1))
+	if err != nil {
+		return ics.Subscribed{}, err
+	}
+	if len(body) > maxICSBytes {
+		return ics.Subscribed{}, errors.New("that calendar is too large")
+	}
+	return ics.ParseCalendar(string(body)), nil
+}
+
+// syncSubscriptions refreshes every calendar this person subscribes to by address.
+//
+// One failing address does not stop the others. A subscription is somebody else's
+// server, and the ordinary state of somebody else's server is that it is fine
+// until one morning it is not — a holiday feed that 404s must not take the
+// football club's fixtures down with it.
+func (s *Server) syncSubscriptions(ctx context.Context, user *store.User) (int, error) {
+	subs, err := s.db.Subscriptions(ctx, user.ID)
+	if err != nil || len(subs) == 0 {
+		return 0, err
+	}
+
+	from, to := calendarWindow(time.Now())
+	written := 0
+	var failures []string
+
+	for _, sub := range subs {
+		if ctx.Err() != nil {
+			return written, ctx.Err()
+		}
+		unlock := s.lockSync("calendar:" + sub.ID)
+
+		calendarID, err := s.db.SubscribedCalendarID(ctx, sub.ID)
+		if err != nil {
+			unlock()
+			failures = append(failures, sub.URL)
+			continue
+		}
+
+		cal, err := s.fetchICS(ctx, sub.URL)
+		if err != nil {
+			unlock()
+			s.log.Warn("subscribed calendar", "err", err, "url", sub.URL, "user", user.ID)
+			failures = append(failures, sub.URL)
+			continue
+		}
+
+		// The name the file calls itself, once. A subscription is added under its
+		// address because that is all there is to go on before it has been fetched.
+		if err := s.db.RenameSubscribedCalendar(ctx, sub.ID, cal.Name); err != nil {
+			s.log.Warn("name subscribed calendar", "err", err)
+		}
+
+		rows := make([]store.CalendarEvent, 0, len(cal.Events))
+		for _, e := range cal.Events {
+			// Outside the window is not stored. The grid asks about a window, the
+			// sweep replaces a window, and a decade of holidays in one file would
+			// otherwise be a decade of rows rewritten every fifteen minutes.
+			if e.EndDay < from || e.StartDay > to {
+				continue
+			}
+			rows = append(rows, store.CalendarEvent{
+				RemoteID: e.UID, Summary: e.Summary, Location: e.Location, URL: e.URL,
+				StartsAt: e.StartsAt, EndsAt: e.EndsAt,
+				StartDay: e.StartDay, EndDay: e.EndDay, AllDay: e.AllDay,
+			})
+		}
+		if err := s.db.ReplaceCalendarEvents(ctx, calendarID, from, to, rows); err != nil {
+			unlock()
+			return written, err
+		}
+		if err := s.db.MarkCalendarSynced(ctx, sub.ID, time.Now()); err != nil {
+			s.log.Warn("mark subscription synced", "err", err)
+		}
+		written += len(rows)
+		unlock()
+	}
+
+	if len(failures) == len(subs) {
+		return written, fmt.Errorf("none of the %d subscribed calendars could be read", len(subs))
+	}
+	return written, nil
+}
+
+// handleSubscribeCalendar adds a calendar somebody only has an address to.
+//
+// Fetched once, here, before it is stored. An address that cannot be read is a
+// typo far more often than it is a server that happens to be down, and telling
+// somebody now — while they are looking at the field they just pasted into — is
+// worth the two seconds. A subscription that silently never fills is the same
+// silence the notifications had.
+func (s *Server) handleSubscribeCalendar(w http.ResponseWriter, r *http.Request) {
+	var req struct {
+		URL  string `json:"url"`
+		Name string `json:"name"`
+	}
+	if err := decodeJSON(w, r, &req); err != nil {
+		return
+	}
+
+	url, err := normaliseCalendarURL(req.URL)
+	if err != nil {
+		writeFieldErrors(w, map[string]string{"url": err.Error()})
+		return
+	}
+
+	user := userFrom(r.Context())
+	ctx, cancel := context.WithTimeout(r.Context(), 20*time.Second)
+	defer cancel()
+
+	cal, err := s.fetchICS(ctx, url)
+	if err != nil {
+		s.log.Warn("subscribe calendar", "err", err, "user", user.ID)
+		writeFieldErrors(w, map[string]string{"url": "that address could not be read"})
+		return
+	}
+
+	name := strings.TrimSpace(req.Name)
+	if name == "" {
+		name = strings.TrimSpace(cal.Name)
+	}
+	if name == "" {
+		name = url
+	}
+
+	account, err := s.db.SubscribeCalendar(r.Context(), user.ID, url, name)
+	if err != nil {
+		// The unique index is the one refusal worth naming: subscribing twice to
+		// the same address is the same calendar fetched twice, with no way to say
+		// which one counts.
+		if errors.Is(err, store.ErrDuplicate) {
+			writeFieldErrors(w, map[string]string{"url": "that calendar is already subscribed"})
+			return
+		}
+		s.storeError(w, r, "subscribe calendar", err)
+		return
+	}
+
+	// The events it already fetched, rather than making the person wait fifteen
+	// minutes for the sweep to prove it worked.
+	if _, err := s.syncSubscriptions(r.Context(), user); err != nil {
+		s.log.Warn("first subscription sync", "err", err)
+	}
+	writeJSON(w, http.StatusCreated, account)
+}
+
+func (s *Server) handleUnsubscribeCalendar(w http.ResponseWriter, r *http.Request) {
+	user := userFrom(r.Context())
+	if err := s.db.DeleteCalendarAccount(r.Context(), user.ID, chi.URLParam(r, "id")); err != nil {
+		s.storeError(w, r, "unsubscribe calendar", err)
+		return
+	}
+	w.WriteHeader(http.StatusNoContent)
+}

internal/httpapi/calendar_test.go

@@ -0,0 +1,471 @@
+package httpapi
+
+import (
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/kristianwind/verdande/internal/config"
+	"github.com/kristianwind/verdande/internal/store"
+)
+
+// fakeCalendarGoogle stands in for the parts of Google this feature touches: the
+// token endpoint, the calendar list and one calendar's events.
+//
+// There is no other way to exercise any of it. The real thing needs a registered
+// OAuth client, an account and somebody's consent, and none of the three can be had
+// inside a test — so the shapes Google returns are written down and the behaviour
+// is checked against them, the way internal/imap is checked against go-imap's own
+// in-process server.
+type fakeCalendarGoogle struct {
+	*httptest.Server
+	// refreshes counts token refreshes, so a test can prove one is not made for a
+	// token that has not expired.
+	refreshes int
+	// refuse makes every API call answer 401, which is what a revoked grant does.
+	refuse bool
+	events map[string][]map[string]any
+}
+
+func newFakeCalendarGoogle(t *testing.T) *fakeCalendarGoogle {
+	t.Helper()
+	g := &fakeCalendarGoogle{events: map[string][]map[string]any{}}
+	g.Server = httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		switch {
+		case r.URL.Path == "/token":
+			g.refreshes++
+			_ = json.NewEncoder(w).Encode(map[string]any{
+				"access_token": "ya29.fresh", "refresh_token": "1//0-refresh",
+				"expires_in": 3600,
+			})
+		case g.refuse:
+			http.Error(w, `{"error":"invalid_credentials"}`, http.StatusUnauthorized)
+		case strings.HasPrefix(r.URL.Path, "/users/me/calendarList"):
+			_ = json.NewEncoder(w).Encode(map[string]any{"items": []map[string]any{
+				{"id": "[email protected]", "summary": "[email protected]", "primary": true,
+					"accessRole": "owner", "backgroundColor": "#3f51b5",
+					"timeZone": "Europe/Copenhagen"},
+				{"id": "fam", "summary": "Familien", "accessRole": "reader",
+					"backgroundColor": "#0b8043"},
+			}})
+		case strings.HasPrefix(r.URL.Path, "/calendars/"):
+			id := strings.TrimSuffix(strings.TrimPrefix(r.URL.Path, "/calendars/"), "/events")
+			items := g.events[id]
+			if items == nil {
+				items = []map[string]any{}
+			}
+			_ = json.NewEncoder(w).Encode(map[string]any{"items": items})
+		default:
+			http.Error(w, "unexpected "+r.URL.Path, http.StatusNotFound)
+		}
+	}))
+	t.Cleanup(g.Close)
+	return g
+}
+
+// connectedCalendar returns a server with a calendar account already connected —
+// the state the OAuth callback leaves behind, without the consent screen nothing
+// can automate.
+func connectedCalendar(t *testing.T, g *fakeCalendarGoogle, tune func(*config.Config)) (*testServer, *store.User) {
+	t.Helper()
+	ts := newTestServerWith(t, func(cfg *config.Config) {
+		cfg.GmailClientID = "test-client"
+		cfg.GmailClientSecret = "test-secret"
+		cfg.GoogleTokenURL = g.URL + "/token"
+		cfg.CalendarAPIURL = g.URL
+		if tune != nil {
+			tune(cfg)
+		}
+	})
+	ts.bootstrap(t)
+
+	user, err := ts.db.UserByEmail(t.Context(), "[email protected]")
+	if err != nil {
+		t.Fatal(err)
+	}
+	account := &store.CalendarAccount{
+		UserID: user.ID, Provider: "google", RefreshToken: "1//0-refresh",
+	}
+	if err := ts.db.SaveCalendarAccount(t.Context(), account); err != nil {
+		t.Fatal(err)
+	}
+	return ts, user
+}
+
+// The scope on the consent screen is what somebody agrees to. It has to be the
+// read-only one, and the redirect has to be the calendar's own — sharing Gmail's
+// would put "which token store do I write" behind a lookup.
+func TestAuthorizeAsksForReadOnlyCalendar(t *testing.T) {
+	g := newFakeCalendarGoogle(t)
+	ts, _ := connectedCalendar(t, g, nil)
+
+	resp, body := ts.do(t, "POST", "/api/v1/calendar/authorize", nil)
+	if resp.StatusCode != http.StatusOK {
+		t.Fatalf("status %d, body %v", resp.StatusCode, body)
+	}
+	url, _ := body["url"].(string)
+	for _, want := range []string{
+		"scope=" + "https%3A%2F%2Fwww.googleapis.com%2Fauth%2Fcalendar.readonly",
+		"%2Foauth%2Fcalendar%2Fcallback",
+		"access_type=offline",
+		"prompt=consent",
+	} {
+		if !strings.Contains(url, want) {
+			t.Errorf("the authorisation URL is missing %q:\n%s", want, url)
+		}
+	}
+	if strings.Contains(url, "calendar.events&") || strings.Contains(url, "auth%2Fcalendar&") {
+		t.Errorf("a writing scope was asked for:\n%s", url)
+	}
+}
+
+// Without a registered client there is nothing to connect through, and the answer
+// has to say that rather than "that already exists".
+func TestAuthorizeWithoutAClientSaysSo(t *testing.T) {
+	ts := newTestServer(t)
+	ts.bootstrap(t)
+
+	resp, body := ts.do(t, "POST", "/api/v1/calendar/authorize", nil)
+	if resp.StatusCode != http.StatusConflict {
+		t.Fatalf("status %d, want 409", resp.StatusCode)
+	}
+	if body["code"] != CodeGmailNotConfigured {
+		t.Errorf("code = %v, want %q", body["code"], CodeGmailNotConfigured)
+	}
+}
+
+// The whole path, minus the consent screen: sync fetches the list, refreshes the
+// events of what was chosen, and the grid endpoint answers with them.
+func TestSyncFetchesTheChosenCalendarsAndTheGridReadsThem(t *testing.T) {
+	g := newFakeCalendarGoogle(t)
+	g.events["fam"] = []map[string]any{
+		{"id": "e1", "summary": "Bestyrelsesmøde", "htmlLink": "https://calendar.google.com/e1",
+			"start": map[string]string{"dateTime": "2026-08-20T14:00:00+02:00"},
+			"end":   map[string]string{"dateTime": "2026-08-20T15:30:00+02:00"}},
+	}
+	g.events["[email protected]"] = []map[string]any{
+		{"id": "e2", "summary": "Skal ikke med",
+			"start": map[string]string{"date": "2026-08-21"},
+			"end":   map[string]string{"date": "2026-08-22"}},
+	}
+	ts, user := connectedCalendar(t, g, nil)
+
+	// The list arrives on the first look at the settings page, which is what
+	// somebody would be doing at this point.
+	resp, body := ts.do(t, "GET", "/api/v1/calendar", nil)
+	if resp.StatusCode != http.StatusOK {
+		t.Fatalf("status %d, body %v", resp.StatusCode, body)
+	}
+	if body["connected"] != true {
+		t.Fatalf("not reported as connected: %v", body)
+	}
+	if body["read_only"] != true {
+		t.Error("the connection did not say it is read-only; an interface that looks " +
+			"editable is one somebody will try to edit")
+	}
+	// The primary calendar's id is the address, which is how the account names
+	// itself without asking for a profile scope as well.
+	if body["account"] != "[email protected]" {
+		t.Errorf("account = %v", body["account"])
+	}
+
+	list, _ := body["calendars"].([]any)
+	if len(list) != 2 {
+		t.Fatalf("got %d calendars, want 2: %v", len(list), body["calendars"])
+	}
+	var famID string
+	for _, raw := range list {
+		c := raw.(map[string]any)
+		if c["shown"] == true {
+			t.Errorf("%v was shown without anybody choosing it", c["name"])
+		}
+		if c["remote_id"] == "fam" {
+			famID = c["id"].(string)
+		}
+	}
+
+	// Nothing is chosen, so a sync writes nothing: an account with a dozen shared
+	// calendars must not fill somebody's grid the moment it is connected.
+	resp, body = ts.do(t, "POST", "/api/v1/calendar/sync", nil)
+	if resp.StatusCode != http.StatusOK || body["events"] != float64(0) {
+		t.Fatalf("an unchosen calendar was fetched: %d %v", resp.StatusCode, body)
+	}
+
+	resp, _ = ts.do(t, "PUT", "/api/v1/calendar/calendars",
+		map[string]any{"shown": []string{famID}})
+	if resp.StatusCode != http.StatusNoContent {
+		t.Fatalf("choosing a calendar: status %d", resp.StatusCode)
+	}
+
+	resp, body = ts.do(t, "POST", "/api/v1/calendar/sync", nil)
+	if resp.StatusCode != http.StatusOK {
+		t.Fatalf("sync: status %d, body %v", resp.StatusCode, body)
+	}
+	if body["events"] != float64(1) {
+		t.Fatalf("events = %v, want 1 — only the chosen calendar", body["events"])
+	}
+
+	resp, body = ts.do(t, "GET",
+		"/api/v1/calendar/events?from=2026-08-01&to=2026-08-31", nil)
+	if resp.StatusCode != http.StatusOK {
+		t.Fatalf("events: status %d, body %v", resp.StatusCode, body)
+	}
+	events, _ := body["events"].([]any)
+	if len(events) != 1 {
+		t.Fatalf("got %d events, want 1: %v", len(events), body["events"])
+	}
+	event := events[0].(map[string]any)
+	if event["summary"] != "Bestyrelsesmøde" || event["start_day"] != "2026-08-20" {
+		t.Errorf("the event came back as %v", event)
+	}
+	// The calendar's colour rides along, or the chip has to ask for it per row.
+	if event["colour"] != "#0b8043" {
+		t.Errorf("colour = %v; two calendars in one grid are told apart by it", event["colour"])
+	}
+	// The window verdande holds is stated, so a grid paged past it can say so
+	// rather than showing an empty month it cannot explain.
+	if body["from"] == "" || body["to"] == "" {
+		t.Error("the answer does not say which window it covers")
+	}
+
+	// And it is one person's calendar. Somebody else on the same instance sees
+	// nothing of it.
+	other := ts.newUser(t, "[email protected]", "Andreas")
+	_, body = other.do(t, "GET", "/api/v1/calendar/events?from=2026-08-01&to=2026-08-31", nil)
+	if events, _ := body["events"].([]any); len(events) != 0 {
+		t.Errorf("somebody else's calendar was visible: %v", body["events"])
+	}
+	_ = user
+}
+
+// A token that has not expired must not be traded in for another. Refreshing on
+// every run burns the quota and makes the failure mode of a bad refresh token
+// arrive on every sweep rather than once an hour.
+func TestAFreshTokenIsNotRefreshed(t *testing.T) {
+	g := newFakeCalendarGoogle(t)
+	ts, user := connectedCalendar(t, g, nil)
+
+	account, err := ts.db.CalendarAccountFor(t.Context(), user.ID, "google")
+	if err != nil {
+		t.Fatal(err)
+	}
+	account.AccessToken = "ya29.still-good"
+	account.ExpiresAt = time.Now().Add(time.Hour)
+	if err := ts.db.SaveCalendarAccount(t.Context(), account); err != nil {
+		t.Fatal(err)
+	}
+
+	if resp, body := ts.do(t, "POST", "/api/v1/calendar/sync", nil); resp.StatusCode != http.StatusOK {
+		t.Fatalf("sync: status %d, body %v", resp.StatusCode, body)
+	}
+	if g.refreshes != 0 {
+		t.Errorf("the token was refreshed %d times while it was still good", g.refreshes)
+	}
+
+	// And an expired one is.
+	account.ExpiresAt = time.Now().Add(-time.Minute)
+	if err := ts.db.SaveCalendarAccount(t.Context(), account); err != nil {
+		t.Fatal(err)
+	}
+	if resp, body := ts.do(t, "POST", "/api/v1/calendar/sync", nil); resp.StatusCode != http.StatusOK {
+		t.Fatalf("sync: status %d, body %v", resp.StatusCode, body)
+	}
+	if g.refreshes != 1 {
+		t.Errorf("an expired token was refreshed %d times, want 1", g.refreshes)
+	}
+}
+
+// Access revoked at Google's end is a connection that has ended, not a failure to
+// retry. Polling it every fifteen minutes for ever is a week of log lines and a
+// connection the person believes they removed.
+func TestRevokedAccessDisconnects(t *testing.T) {
+	g := newFakeCalendarGoogle(t)
+	ts, user := connectedCalendar(t, g, nil)
+
+	account, _ := ts.db.CalendarAccountFor(t.Context(), user.ID, "google")
+	account.AccessToken = "ya29.revoked"
+	account.ExpiresAt = time.Now().Add(time.Hour)
+	if err := ts.db.SaveCalendarAccount(t.Context(), account); err != nil {
+		t.Fatal(err)
+	}
+	g.refuse = true
+
+	resp, body := ts.do(t, "POST", "/api/v1/calendar/sync", nil)
+	if resp.StatusCode != StatusUpstreamRefused {
+		t.Fatalf("status %d, want %d — Google saying no is not this server breaking",
+			resp.StatusCode, StatusUpstreamRefused)
+	}
+	if body["code"] != CodeCalendarFailed {
+		t.Errorf("code = %v, want %q — `internal_error` is shown as a generic sentence, "+
+			"which throws the diagnosis away", body["code"], CodeCalendarFailed)
+	}
+
+	gone, err := ts.db.CalendarAccountFor(t.Context(), user.ID, "google")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if gone != nil {
+		t.Error("the connection is still there after Google refused the token")
+	}
+
+	// And the failure is in the error log, which is the point of having one: a
+	// sync that has been failing for a week is invisible otherwise.
+	_, logged := ts.do(t, "GET", "/api/v1/errors", nil)
+	rows, _ := logged["errors"].([]any)
+	if len(rows) == 0 {
+		t.Fatal("nothing was recorded")
+	}
+	if row := rows[0].(map[string]any); row["what"] != "sync calendar" {
+		t.Errorf("what = %v, want \"sync calendar\"", row["what"])
+	}
+}
+
+// Disconnecting takes the copy with it. None of it is the person's own work, and
+// a calendar left behind after the account is gone is a frozen lie about a day.
+func TestDisconnectingRemovesTheEvents(t *testing.T) {
+	g := newFakeCalendarGoogle(t)
+	g.events["fam"] = []map[string]any{
+		{"id": "e1", "summary": "Møde",
+			"start": map[string]string{"date": "2026-08-20"},
+			"end":   map[string]string{"date": "2026-08-21"}},
+	}
+	ts, user := connectedCalendar(t, g, nil)
+
+	ts.do(t, "GET", "/api/v1/calendar", nil)
+	account, _ := ts.db.CalendarAccountFor(t.Context(), user.ID, "google")
+	calendars, _ := ts.db.Calendars(t.Context(), account.ID)
+	var famID string
+	for _, c := range calendars {
+		if c.RemoteID == "fam" {
+			famID = c.ID
+		}
+	}
+	ts.do(t, "PUT", "/api/v1/calendar/calendars", map[string]any{"shown": []string{famID}})
+	ts.do(t, "POST", "/api/v1/calendar/sync", nil)
+
+	if resp, _ := ts.do(t, "DELETE", "/api/v1/calendar", nil); resp.StatusCode != http.StatusNoContent {
+		t.Fatalf("disconnect: status %d", resp.StatusCode)
+	}
+
+	_, body := ts.do(t, "GET", "/api/v1/calendar/events?from=2026-08-01&to=2026-08-31", nil)
+	if events, _ := body["events"].([]any); len(events) != 0 {
+		t.Errorf("events survived the disconnect: %v", body["events"])
+	}
+	_, body = ts.do(t, "GET", "/api/v1/calendar", nil)
+	if body["connected"] != false {
+		t.Error("still reported as connected")
+	}
+}
+
+// A range that is not a date has to be refused, not guessed at. An empty `from`
+// compared as a string matches everything before it, which is a grid quietly
+// answering a question nobody asked.
+func TestEventsRefuseARangeThatIsNotADate(t *testing.T) {
+	g := newFakeCalendarGoogle(t)
+	ts, _ := connectedCalendar(t, g, nil)
+
+	for _, query := range []string{
+		"", "?from=2026-08-01", "?from=&to=2026-08-31",
+		"?from=i+morgen&to=2026-08-31", "?from=2026-08-01&to=2026-13-40",
+	} {
+		resp, body := ts.do(t, "GET", "/api/v1/calendar/events"+query, nil)
+		if resp.StatusCode != http.StatusUnprocessableEntity {
+			t.Errorf("%q: status %d, want 422 (%v)", query, resp.StatusCode, body)
+		}
+	}
+}
+
+// A person with no calendar connected still opens the view. It has to answer, and
+// answer emptily, rather than fail — the grid is also verdande's own tasks, and
+// they must not disappear because Google is not set up.
+func TestTheGridAnswersWithNoCalendarConnected(t *testing.T) {
+	ts := newTestServer(t)
+	ts.bootstrap(t)
+
+	resp, body := ts.do(t, "GET", "/api/v1/calendar/events?from=2026-08-01&to=2026-08-31", nil)
+	if resp.StatusCode != http.StatusOK {
+		t.Fatalf("status %d, body %v", resp.StatusCode, body)
+	}
+	if events, ok := body["events"].([]any); !ok || len(events) != 0 {
+		t.Errorf("events = %v, want an empty list rather than null", body["events"])
+	}
+
+	resp, body = ts.do(t, "GET", "/api/v1/calendar", nil)
+	if resp.StatusCode != http.StatusOK || body["connected"] != false {
+		t.Fatalf("status %d, body %v", resp.StatusCode, body)
+	}
+	if body["has_client"] != false {
+		t.Error("an instance with no OAuth registration claimed to have one; the page " +
+			"would offer a button that answers 409")
+	}
+	// Spelled out even when nothing is connected: it is what has to be registered
+	// with Google, and it is the single most likely thing to be wrong.
+	if uri, _ := body["redirect_uri"].(string); !strings.HasSuffix(uri, "/oauth/calendar/callback") {
+		t.Errorf("redirect_uri = %q", uri)
+	}
+}
+
+// A slow Google must not hold the request open until something in front of this
+// server gives up on it and answers with its own HTML.
+func TestASlowCalendarDoesNotHangTheRequest(t *testing.T) {
+	blocked := make(chan struct{})
+	defer close(blocked)
+	slow := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		select {
+		case <-blocked:
+		case <-r.Context().Done():
+		}
+	}))
+	defer slow.Close()
+
+	ts := newTestServerWith(t, func(cfg *config.Config) {
+		cfg.GmailClientID = "test-client"
+		cfg.GmailClientSecret = "test-secret"
+		cfg.GoogleTokenURL = slow.URL + "/token"
+		cfg.CalendarAPIURL = slow.URL
+		// A second rather than the real twenty-five: what is being tested is that a
+		// budget is applied at all, and spending the production one on every run
+		// would put half a minute into the suite to learn the same thing.
+		cfg.CalendarSyncBudget = time.Second
+	})
+	ts.bootstrap(t)
+
+	user, err := ts.db.UserByEmail(t.Context(), "[email protected]")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := ts.db.SaveCalendarAccount(t.Context(), &store.CalendarAccount{
+		UserID: user.ID, Provider: "google", RefreshToken: "r",
+		AccessToken: "a", ExpiresAt: time.Now().Add(time.Hour),
+	}); err != nil {
+		t.Fatal(err)
+	}
+
+	// Its own client, because the shared one gives up after ten seconds — which is
+	// shorter than the budget being tested and would prove nothing either way.
+	req, _ := http.NewRequest("POST", ts.URL+"/api/v1/calendar/sync", nil)
+	req.Header.Set("Sec-Fetch-Site", "same-origin")
+	for _, c := range ts.client.Jar.Cookies(mustParse(t, ts.URL)) {
+		req.AddCookie(c)
+	}
+
+	started := time.Now()
+	resp, err := (&http.Client{Timeout: 90 * time.Second}).Do(req)
+	if err != nil {
+		t.Fatalf("the request never came back (%v after %s); the sync has no budget of its "+
+			"own, and whatever sits in front of this server answers for it",
+			err, time.Since(started).Round(time.Second))
+	}
+	defer resp.Body.Close()
+
+	if took := time.Since(started); took > 10*time.Second {
+		t.Errorf("the sync took %s; the budget is not being applied", took.Round(time.Second))
+	}
+	if resp.StatusCode >= 500 {
+		t.Errorf("status %d — a slow Google is not this server breaking", resp.StatusCode)
+	}
+}

internal/httpapi/comments_handlers.go

@@ -225,17 +225,32 @@ func (s *Server) handleUploadAttachment(w http.ResponseWriter, r *http.Request)
 
 	a := &store.Attachment{
 		TaskID:     taskID,
-		CommentID:  r.FormValue("comment_id"),
 		Filename:   safeFilename(header.Filename),
 		MimeType:   detectMime(header.Filename, header.Header.Get("Content-Type")),
 		Size:       size,
 		Path:       stored,
 		UploadedBy: user.ID,
 	}
+
 	// An attachment hangs on a task or on a comment, never both — the schema says
 	// so, and the form may have supplied a comment id.
-	if a.CommentID != "" {
-		a.TaskID = ""
+	//
+	// The comment is resolved and checked against the task in the URL. It was
+	// taken on trust, which meant the permission check above guarded the *task
+	// somebody named* while the file landed on *whatever comment they asked for*.
+	// A viewer on a shared project can list its comments, so she could read an id
+	// there and then post to a task in her own project with that id attached: the
+	// file appears under somebody else's comment, in a project she may only read,
+	// and is served to everyone in it from this origin under a name she chose.
+	// Somebody removed from a project could do the same with ids they kept.
+	if id := r.FormValue("comment_id"); id != "" {
+		owner, err := s.db.CommentTask(r.Context(), id)
+		if err != nil || owner != taskID {
+			os.Remove(filepath.Join(s.cfg.FilesDir(), stored))
+			writeError(w, http.StatusNotFound, CodeNotFound, "not found")
+			return
+		}
+		a.CommentID, a.TaskID = id, ""
 	}
 
 	if err := s.db.CreateAttachment(r.Context(), a); err != nil {
@@ -327,6 +342,30 @@ func (s *Server) reachAttachment(r *http.Request, attachmentID string) (canEdit
 		return true, nil
 	}
 
+	// A file inside a note follows the note, which follows its project — the same
+	// chain everything else here follows. Without this a picture imported with a
+	// note answered 404 while sitting in the middle of the text that named it.
+	if a.NoteID != "" {
+		n, err := s.db.Note(r.Context(), a.NoteID)
+		if err != nil {
+			return false, err
+		}
+		if n == nil {
+			return false, store.ErrNotFound
+		}
+		if n.ProjectID == "" {
+			if n.CreatedBy != user.ID {
+				return false, store.ErrNotFound
+			}
+			return true, nil
+		}
+		role, err := store.RequireProjectRole(r.Context(), s.db, n.ProjectID, user.ID, store.RoleViewer)
+		if err != nil {
+			return false, err
+		}
+		return role.CanEdit(), nil
+	}
+
 	taskID, err := s.db.AttachmentTask(r.Context(), attachmentID)
 	if err != nil {
 		return false, err
@@ -370,12 +409,30 @@ func (s *Server) handleDownloadAttachment(w http.ResponseWriter, r *http.Request
 	}
 	defer f.Close()
 
-	// Everything is served as a download rather than rendered. An uploaded SVG or
-	// HTML file displayed inline would run its own script on this origin, with the
-	// session cookie attached — attachments are the one place a user supplies
-	// content that another user opens.
-	w.Header().Set("Content-Type", "application/octet-stream")
-	w.Header().Set("Content-Disposition", "attachment; filename*=UTF-8''"+
+	// Almost everything is served as a download rather than rendered. An uploaded
+	// SVG or HTML file displayed inline would run its own script on this origin,
+	// with the session cookie attached — attachments are the one place a user
+	// supplies content that another user opens.
+	//
+	// The exception is a short list of raster images, and it is not a softening of
+	// that rule but what makes a note work: a note carries its pictures in the text
+	// as `![](…)`, and served as octet-stream every one of them is a broken image.
+	// The whole Apple Notes import exists to bring those pictures along.
+	//
+	// Safe because it is an allowlist of formats that cannot carry script, sent as
+	// the exact type with `nosniff` — so the browser must treat it as that image or
+	// not at all, and can never be talked into reading it as HTML. SVG is
+	// deliberately absent: it is a document, not a picture, and it is the one image
+	// type that can run script.
+	disposition := "attachment"
+	contentType := "application/octet-stream"
+	if inlineImage[a.MimeType] {
+		disposition = "inline"
+		contentType = a.MimeType
+	}
+
+	w.Header().Set("Content-Type", contentType)
+	w.Header().Set("Content-Disposition", disposition+"; filename*=UTF-8''"+
 		strings.ReplaceAll(mime.QEncoding.Encode("utf-8", a.Filename), " ", "%20"))
 	w.Header().Set("X-Content-Type-Options", "nosniff")
 	w.Header().Set("Content-Length", fmt.Sprint(a.Size))
@@ -384,6 +441,24 @@ func (s *Server) handleDownloadAttachment(w http.ResponseWriter, r *http.Request
 	http.ServeContent(w, r, a.Filename, a.CreatedAt, f)
 }
 
+// inlineImage is what may be shown rather than downloaded.
+//
+// Raster formats only, and named one by one rather than matched on an "image/"
+// prefix: the prefix would let image/svg+xml through, which is a document that
+// can run script, and a list that grows by accident is how that happens.
+var inlineImage = map[string]bool{
+	"image/png":  true,
+	"image/jpeg": true,
+	"image/gif":  true,
+	"image/webp": true,
+	"image/avif": true,
+	// Sendes med, selv om ingen browser viser den endnu. Den er lige så ufarlig
+	// som de andre, og en iPhone-note er fuld af dem — den dag Safari viser dem,
+	// virker de, uden at nogen skal huske hvorfor de ikke gjorde.
+	"image/heic": true,
+	"image/heif": true,
+}
+
 func (s *Server) handleDeleteAttachment(w http.ResponseWriter, r *http.Request) {
 	attachmentID := chi.URLParam(r, "attachmentID")
 

internal/httpapi/csp_header_test.go

@@ -0,0 +1,66 @@
+package httpapi
+
+import (
+	"strings"
+	"testing"
+)
+
+// Politikken skal stå i svaret, og den skal stadig være stram.
+//
+// Den er dét, der gjorde en XSS i noteeditoren til indsat HTML frem for kørt
+// script, dengang en `alt` slap uden om sin undslupning — og der var ingen prøve
+// på, at headeren overhovedet blev sendt. En sikkerhedsforanstaltning, ingen
+// prøve rører, er en, der kan forsvinde i en oprydning uden at nogen opdager det.
+func TestEveryResponseCarriesAStrictCSP(t *testing.T) {
+	ts := newTestServer(t)
+	ts.bootstrap(t)
+
+	resp, _ := ts.do(t, "GET", "/api/v1/auth/me", nil)
+	policy := resp.Header.Get("Content-Security-Policy")
+	if policy == "" {
+		t.Fatal("der er ingen Content-Security-Policy på svaret")
+	}
+
+	// Målt på script-src alene, og ikke på hele politikken.
+	//
+	// `style-src 'unsafe-inline'` står der med vilje og er forklaret i csp.go:
+	// Svelte skriver stilarter ind i dokumentet, og en indsat stil kan gøre en
+	// side grim, ikke køre kode. Det er script-src, der afgør, om indsat HTML
+	// bliver til et kørende script, og det er derfor den, prøven ser på.
+	scriptSrc := ""
+	for _, part := range strings.Split(policy, ";") {
+		if strings.HasPrefix(strings.TrimSpace(part), "script-src") {
+			scriptSrc = part
+		}
+	}
+	if scriptSrc == "" {
+		t.Fatal("der er ingen script-src i politikken")
+	}
+	for _, forbidden := range []string{"'unsafe-inline'", "'unsafe-eval'", "'unsafe-hashes'", "'strict-dynamic'"} {
+		if strings.Contains(scriptSrc, forbidden) {
+			t.Errorf("script-src indeholder %s: %q", forbidden, strings.TrimSpace(scriptSrc))
+		}
+	}
+
+	// Og de fire, der skal være der.
+	for _, want := range []string{"script-src", "object-src 'none'", "base-uri 'none'", "frame-ancestors 'none'"} {
+		if !strings.Contains(policy, want) {
+			t.Errorf("politikken mangler %q", want)
+		}
+	}
+}
+
+// Et bilag må ikke kunne blive læst som et dokument.
+func TestAttachmentsAreNotServedAsDocuments(t *testing.T) {
+	for _, mime := range []string{"image/svg+xml", "text/html", "application/xhtml+xml", "text/xml"} {
+		if inlineImage[mime] {
+			t.Errorf("%s står på listen over det, der vises inline", mime)
+		}
+	}
+	// Og listen skal faktisk kunne noget, ellers virker billeder i noter ikke.
+	for _, mime := range []string{"image/png", "image/jpeg"} {
+		if !inlineImage[mime] {
+			t.Errorf("%s mangler; billeder i noter kan ikke vises", mime)
+		}
+	}
+}

internal/httpapi/errors.go

@@ -63,6 +63,11 @@ const (
 	// diagnosis — a wrong app password, a host that is not listening, a folder that
 	// is not there — and it says it in its own words.
 	CodeMailboxFailed = "mailbox_failed"
+
+	// And for a calendar read from Google. Its own code rather than the Gmail one,
+	// because the sentence the interface wraps it in names where it came from — and
+	// "Gmail said no" about a calendar sends somebody to the wrong panel.
+	CodeCalendarFailed = "calendar_failed"
 )
 
 // errLastAdmin is returned to the caller that already wrote the response, so it

internal/httpapi/gmail_handlers.go

@@ -25,18 +25,16 @@ const defaultGmailSyncBudget = 25 * time.Second
 // to redeploy a container to paste a client id.
 // gmailClient is the API client, pointed wherever the config says Google is.
 func (s *Server) gmailClient(accessToken string) *gmail.Client {
-	return gmail.NewClient(accessToken).At(gmail.Endpoints{
-		Token: s.cfg.GmailTokenURL, API: s.cfg.GmailAPIURL,
-	})
+	return gmail.NewClient(accessToken).At(s.cfg.GmailAPIURL)
 }
 
 func (s *Server) gmailConfig(ctx context.Context) gmail.Config {
-	endpoints := gmail.Endpoints{Token: s.cfg.GmailTokenURL, API: s.cfg.GmailAPIURL}
 	cfg := gmail.Config{
 		ClientID:     s.cfg.GmailClientID,
 		ClientSecret: s.cfg.GmailClientSecret,
 		RedirectURL:  s.cfg.GmailRedirectURL(),
-		Endpoints:    endpoints,
+		Scope:        gmail.Scope,
+		TokenURL:     s.cfg.GoogleTokenURL,
 	}
 	if cfg.ClientID != "" && cfg.ClientSecret != "" {
 		return cfg
@@ -251,6 +249,17 @@ func (s *Server) handleGmailSyncNow(w http.ResponseWriter, r *http.Request) {
 //
 // Returns how many were made. Also used by the background job, which is why it
 // takes a context and a user rather than a request.
+// maxGmailSeen bounds the list of message ids already turned into tasks.
+//
+// Gmail is read-only here — the scope is `gmail.readonly`, deliberately, because
+// asking for less is what makes the consent screen something a person can agree
+// to — so verdande cannot unstar a message the way the IMAP side unflags one. The
+// record has to live on this side, and a record on this side has to be bounded.
+//
+// A count rather than the previous rule of "whatever Gmail returned this run",
+// which was not a bound but a way of forgetting.
+const maxGmailSeen = 2000
+
 func (s *Server) SyncGmail(ctx context.Context, user *store.User) (int, error) {
 	box, err := s.db.MailboxOfKind(ctx, user.ID, "gmail")
 	if err != nil {
@@ -260,7 +269,7 @@ func (s *Server) SyncGmail(ctx context.Context, user *store.User) (int, error) {
 		// The same guard as the mailboxes read over IMAP, for the same reason: a
 		// press of "Fetch now" during the sweep would otherwise make two runs from
 		// one marker.
-		unlock := s.lockMailbox(box.ID)
+		unlock := s.lockSync(box.ID)
 		defer unlock()
 		if fresh, err := s.db.MailboxOfKind(ctx, user.ID, "gmail"); err == nil && fresh != nil {
 			box = fresh
@@ -362,14 +371,35 @@ func (s *Server) SyncGmail(ctx context.Context, user *store.User) (int, error) {
 	}
 
 	if created > 0 {
-		// Only the ids Gmail still returns are kept, so the list cannot grow
-		// without bound as messages fall out of the 30-day window.
-		keep := make([]string, 0, len(ids))
+		// The ids this run saw, on top of the ones already known.
+		//
+		// It used to keep only the ids Gmail returned *this run*, to stop the list
+		// growing without bound. That threw away every id that was not on the page
+		// it happened to fetch — and the query is capped, so on an account with more
+		// starred mail than one page, each run forgot the messages the last one had
+		// remembered. They came back unseen, and became tasks again, and again. That
+		// is the duplicate.
+		//
+		// Bounded by a count instead. Newest first, and a ceiling far above any
+		// plausible page, so an id leaves the list because it is old rather than
+		// because it was not in the last answer.
+		keep := make([]string, 0, len(ids)+len(box.Seen))
+		added := map[string]bool{}
 		for _, id := range ids {
-			if seen[id] {
+			if seen[id] && !added[id] {
 				keep = append(keep, id)
+				added[id] = true
 			}
 		}
+		for _, id := range box.Seen {
+			if !added[id] {
+				keep = append(keep, id)
+				added[id] = true
+			}
+		}
+		if len(keep) > maxGmailSeen {
+			keep = keep[:maxGmailSeen]
+		}
 		box.Seen = keep
 		box.LastSyncAt = time.Now()
 		if err := s.db.SaveMailbox(ctx, box); err != nil {

internal/httpapi/gmail_test.go

@@ -29,7 +29,7 @@ func TestAGmailFailureSaysWhatGmailSaidAndIsRecorded(t *testing.T) {
 	ts := newTestServerWith(t, func(cfg *config.Config) {
 		cfg.GmailClientID = "test-client"
 		cfg.GmailClientSecret = "test-secret"
-		cfg.GmailTokenURL = google.URL + "/token"
+		cfg.GoogleTokenURL = google.URL + "/token"
 		cfg.GmailAPIURL = google.URL
 	})
 	ts.bootstrap(t)
@@ -97,7 +97,7 @@ func TestASlowMailboxDoesNotHangTheRequest(t *testing.T) {
 	ts := newTestServerWith(t, func(cfg *config.Config) {
 		cfg.GmailClientID = "test-client"
 		cfg.GmailClientSecret = "test-secret"
-		cfg.GmailTokenURL = google.URL + "/token"
+		cfg.GoogleTokenURL = google.URL + "/token"
 		cfg.GmailAPIURL = google.URL
 		// A second rather than the real twenty-five: what is being tested is that a
 		// budget is applied at all, and spending the production one on every run

internal/httpapi/integrations_handlers.go

@@ -11,6 +11,7 @@ import (
 	"github.com/kristianwind/verdande/internal/ai"
 	"github.com/kristianwind/verdande/internal/auth"
 	"github.com/kristianwind/verdande/internal/quickadd"
+	"github.com/kristianwind/verdande/internal/safedial"
 	"github.com/kristianwind/verdande/internal/store"
 )
 
@@ -214,6 +215,24 @@ func (s *Server) handleSetAISettings(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
+	// The address is checked where it is typed, as well as when it is dialled.
+	//
+	// safedial refuses a private destination at connect time and is the actual
+	// wall; this is so the person entering it hears about it now rather than
+	// discovering it later as a failed summary. A scheme other than http or https
+	// is refused outright — file:// and gopher:// are not providers.
+	if url := strings.TrimSpace(req.BaseURL); url != "" {
+		if !strings.HasPrefix(url, "http://") && !strings.HasPrefix(url, "https://") {
+			writeFieldErrors(w, map[string]string{"base_url": "must start with http:// or https://"})
+			return
+		}
+		if reason := safedial.CheckURL(url); reason != "" {
+			writeFieldErrors(w, map[string]string{"base_url": reason})
+			return
+		}
+		req.BaseURL = url
+	}
+
 	existing, err := s.aiConfig(r, user.ID)
 	if err != nil {
 		s.internal(w, r, "ai settings", err)

internal/httpapi/integrations_test.go

@@ -2,13 +2,18 @@ package httpapi
 
 import (
 	"encoding/json"
+	"errors"
+	"fmt"
 	"io"
 	"net/http"
+	"net/http/httptest"
 	"net/url"
 	"strings"
 	"testing"
+	"time"
 
 	"github.com/kristianwind/verdande/internal/config"
+	"github.com/kristianwind/verdande/internal/store"
 )
 
 // --- MCP -----------------------------------------------------------------------------
@@ -250,6 +255,116 @@ func (ts *testServer) apiToken(t *testing.T, userID string) string {
 	return token
 }
 
+// The promise of sharing has to hold at every door, not just the API's.
+//
+// TestViewerCannotMutateThroughTheAPI asserts a viewer cannot write, and it
+// asserts it against /api/v1. CalDAV is a second door into the same tasks, and it
+// authorised differently: it checked the caller's standing in the project *named
+// in the URL* and then took the task id from the URL as well. Nothing tied the
+// two together.
+//
+// So a viewer on somebody else's project could name a project of their own —
+// their Inbox, which everybody owns and everybody may edit — and put the other
+// project's task id in the filename. The project check passed on the Inbox, and
+// the write landed on a task in a project they may only read.
+func TestAViewerCannotWriteThroughCalDAV(t *testing.T) {
+	ts := newTestServer(t)
+	ts.bootstrap(t)
+	ts.newUser(t, "[email protected]", "Viewer")
+
+	_, project := ts.do(t, "POST", "/api/v1/projects", map[string]any{"name": "Delt"})
+	projectID := project["id"].(string)
+	_, task := ts.do(t, "POST", "/api/v1/tasks", map[string]any{
+		"content": "en opgave", "project_id": projectID,
+	})
+	taskID := task["id"].(string)
+
+	if resp, body := ts.do(t, "POST", "/api/v1/projects/"+projectID+"/invites", map[string]any{
+		"email": "[email protected]", "role": "viewer",
+	}); resp.StatusCode != http.StatusOK {
+		t.Fatalf("invite: %d %v", resp.StatusCode, body)
+	}
+
+	them, err := ts.db.UserByEmail(t.Context(), "[email protected]")
+	if err != nil {
+		t.Fatal(err)
+	}
+	token := ts.apiToken(t, them.ID)
+
+	// Their own Inbox: a project they own and may edit, and the one every account
+	// has. It is what makes the URL check pass.
+	projects, err := ts.db.ListProjects(t.Context(), them.ID, false)
+	if err != nil {
+		t.Fatal(err)
+	}
+	var inbox string
+	for _, p := range projects {
+		if p.IsInbox {
+			inbox = p.ID
+		}
+	}
+	if inbox == "" {
+		t.Fatal("the viewer has no inbox")
+	}
+
+	vtodo := "BEGIN:VCALENDAR\r\nVERSION:2.0\r\nBEGIN:VTODO\r\nUID:" + taskID +
+		"\r\nSUMMARY:kapret\r\nSTATUS:COMPLETED\r\nEND:VTODO\r\nEND:VCALENDAR\r\n"
+
+	resp := ts.dav(t, "PUT", "/caldav/"+them.ID+"/"+inbox+"/"+taskID+".ics",
+		token, them.Email, vtodo)
+	if resp.StatusCode < 400 {
+		t.Errorf("a viewer wrote through CalDAV: status %d", resp.StatusCode)
+	}
+
+	// And the task is as its owner left it. The status alone is not the assertion:
+	// the question is whether anything moved.
+	_, after := ts.do(t, "GET", "/api/v1/tasks/"+taskID, nil)
+	if after["content"] != "en opgave" {
+		t.Errorf("the task was renamed by a viewer: %v", after["content"])
+	}
+	if after["completed"] != false {
+		t.Error("the task was completed by a viewer")
+	}
+}
+
+// A task may only be addressed under the project it is actually in.
+//
+// The same hole seen from the other side: an editor on two projects could reach a
+// task in one of them through the other's URL. Nothing is escalated by it — they
+// may edit both — but it is the check that was missing, and a URL that lies about
+// where a resource lives is how the viewer case got in.
+func TestCalDAVRefusesATaskFromAnotherProject(t *testing.T) {
+	ts := newTestServer(t)
+	ts.bootstrap(t)
+
+	user, err := ts.db.UserByEmail(t.Context(), "[email protected]")
+	if err != nil {
+		t.Fatal(err)
+	}
+	token := ts.apiToken(t, user.ID)
+
+	_, one := ts.do(t, "POST", "/api/v1/projects", map[string]any{"name": "Et"})
+	_, two := ts.do(t, "POST", "/api/v1/projects", map[string]any{"name": "To"})
+	_, task := ts.do(t, "POST", "/api/v1/tasks", map[string]any{
+		"content": "hører til Et", "project_id": one["id"].(string),
+	})
+	taskID := task["id"].(string)
+
+	vtodo := "BEGIN:VCALENDAR\r\nVERSION:2.0\r\nBEGIN:VTODO\r\nUID:" + taskID +
+		"\r\nSUMMARY:flyttet i smug\r\nEND:VTODO\r\nEND:VCALENDAR\r\n"
+
+	resp := ts.dav(t, "PUT", "/caldav/"+user.ID+"/"+two["id"].(string)+"/"+taskID+".ics",
+		token, user.Email, vtodo)
+	if resp.StatusCode < 400 {
+		t.Errorf("a task was written under the wrong project: status %d", resp.StatusCode)
+	}
+
+	_, after := ts.do(t, "GET", "/api/v1/tasks/"+taskID, nil)
+	if after["content"] != "hører til Et" {
+		t.Errorf("the task changed: %v", after["content"])
+	}
+}
+
 func TestCalDAVRequiresCredentials(t *testing.T) {
 	ts := newTestServer(t)
 	ts.bootstrap(t)
@@ -562,6 +677,48 @@ func TestAIKeyIsNeverReturned(t *testing.T) {
 	}
 }
 
+// Connecting something else must not delete the AI provider.
+//
+// Reported from use as "the AI settings are not saved": they were saved, and then
+// taken. `user_settings` had `user_id` as its whole primary key, and the upsert
+// renamed `scope` on conflict — so the `ai`, `gmail` and `calendar` scopes shared
+// one row and each write deleted the other two. Every write returned 204.
+//
+// Through the handlers, because that is where it was seen. The shape is asserted
+// against the store as well: see TestOnePersonCanHaveSettingsForMoreThanOneThing.
+func TestTheAIProviderSurvivesConnectingSomethingElse(t *testing.T) {
+	ts := newTestServer(t)
+	ts.bootstrap(t)
+
+	ts.do(t, "PUT", "/api/v1/ai/settings", map[string]any{
+		"provider": "anthropic", "model": "claude-sonnet-5", "api_key": "sk-hemmelig-nøgle",
+	})
+
+	user, err := ts.db.UserByEmail(t.Context(), "[email protected]")
+	if err != nil {
+		t.Fatal(err)
+	}
+	// What the calendar and the mailbox handlers do when a handshake starts: write
+	// their own scope for the same person.
+	for _, scope := range []string{"calendar", "gmail"} {
+		if err := ts.db.SetUserSettings(t.Context(), user.ID, scope,
+			map[string]any{"pkce_state": "s-" + scope}); err != nil {
+			t.Fatalf("save %s: %v", scope, err)
+		}
+	}
+
+	_, body := ts.do(t, "GET", "/api/v1/ai/settings", nil)
+	if body["provider"] != "anthropic" {
+		t.Errorf("the provider is %v after connecting two other things, want anthropic", body["provider"])
+	}
+	if body["model"] != "claude-sonnet-5" {
+		t.Errorf("the model is %v", body["model"])
+	}
+	if body["has_key"] != true {
+		t.Error("the key was taken with it")
+	}
+}
+
 func TestGmailSettings(t *testing.T) {
 	ts := newTestServer(t)
 	ts.bootstrap(t)
@@ -1316,3 +1473,172 @@ func TestTheMailAddressCanBeRotated(t *testing.T) {
 		t.Error("the second rotation returned the same address")
 	}
 }
+
+// "Der kommer ingen notifikationer" må kunne besvares.
+//
+// Alt om det var usynligt: indstillingssiden sagde "til for denne enhed", så snart
+// der fandtes et abonnement, og en push, tjenesten afviste, gik i en Debug-linje,
+// som ikke skrives på en instans, der kører på standardniveau. Man kunne ikke
+// skelne "browseren tilmeldte sig aldrig" fra "tjenesten afviste den" fra "der er
+// ikke noget forfaldent endnu" — tre forskellige problemer med ét udseende.
+func TestATestNotificationSaysWhatHappenedToIt(t *testing.T) {
+	ts := newTestServer(t)
+	ts.bootstrap(t)
+
+	// Ingen enheder: svaret skal sige nul frem for at lade som om det gik godt.
+	resp, body := ts.do(t, "POST", "/api/v1/push/test", map[string]any{
+		"title": "Prøve", "body": "kom den frem?",
+	})
+	if resp.StatusCode != http.StatusOK {
+		t.Fatalf("status %d, body %v", resp.StatusCode, body)
+	}
+	if body["subscriptions"] != float64(0) {
+		t.Errorf("subscriptions = %v uden tilmeldte enheder", body["subscriptions"])
+	}
+
+	// En enhed, der peger på en tjeneste, som ikke findes. Den skal komme tilbage
+	// som et navngivent afslag og ikke som tavshed.
+	user, err := ts.db.UserByEmail(t.Context(), "[email protected]")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := ts.db.SavePushSubscription(t.Context(), &store.PushSubscription{
+		UserID:   user.ID,
+		Endpoint: "https://push.example.invalid/abc",
+		P256dh:   "BEl62iUYgUivxIkv69yViEuiBIa-Ib9-SkvMeAtA3LFgDzkrxZJjSgSnfckjBJuBkr3qBUYIHBQFLXYp5Nksh8U",
+		Auth:     "aUZmY2xDS2FQUXJJVmJIeA",
+	}); err != nil {
+		t.Fatal(err)
+	}
+
+	_, body = ts.do(t, "POST", "/api/v1/push/test", map[string]any{"title": "Prøve"})
+	if body["subscriptions"] != float64(1) {
+		t.Fatalf("subscriptions = %v", body["subscriptions"])
+	}
+	failed, _ := body["failed"].([]any)
+	if len(failed) != 1 {
+		t.Fatalf("failed har %d poster, want 1 — afslaget blev slugt", len(failed))
+	}
+	first, _ := failed[0].(map[string]any)
+	if first["service"] != "push.example.invalid" {
+		t.Errorf("service = %v", first["service"])
+	}
+	if first["reason"] == "" || first["reason"] == nil {
+		t.Error("afslaget kom uden en grund")
+	}
+	// Og aldrig hele adressen: resten af den er den legitimation, tjenesten gav
+	// enheden, og den hører hverken i et svar, en log eller et skærmbillede.
+	if strings.Contains(fmt.Sprint(first), "/abc") {
+		t.Errorf("endepunktet lækkede med ud: %v", first)
+	}
+}
+
+// Et abonnement på en kalender, man kun har en adresse til.
+//
+// Bedt om som "abonnering af flere kalendere (ics og webcal?)". Google-vejen er
+// OAuth og én konto pr. person; det her er en adresse, og man har flere. Det er
+// også den eneste vej for en privat konto, som en Internal-registrering afviser
+// med `org_internal`.
+//
+// Prøven går uden om handleren og ind i det, den kalder. Grunden er væggen:
+// `httptest` lytter på loopback, og safedial nægter — både når adressen skrives
+// ned og igen når den hentes. Det er rigtigt, og det skal ikke kunne slås fra fra
+// en prøve. Så adressereglerne prøves for sig i TestWebcalIsRewrittenToHTTPS, og
+// her prøves resten af vejen: hentning, format, navn, gitteret og afmeldingen.
+func TestSubscribingToACalendarByAddress(t *testing.T) {
+	ts := newTestServer(t)
+	ts.bootstrap(t)
+
+	day := time.Now().AddDate(0, 0, 2).Format("20060102")
+	feedBody := "BEGIN:VCALENDAR\r\nVERSION:2.0\r\nX-WR-CALNAME:Helligdage\r\n" +
+		"BEGIN:VEVENT\r\nUID:[email protected]\r\n" +
+		"DTSTART;VALUE=DATE:" + day + "\r\nDTEND;VALUE=DATE:" + day + "\r\n" +
+		"SUMMARY:Grundlovsdag\r\nEND:VEVENT\r\nEND:VCALENDAR\r\n"
+
+	var hits int
+	feed := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		hits++
+		w.Header().Set("Content-Type", "text/calendar")
+		w.Write([]byte(feedBody))
+	}))
+	defer feed.Close()
+	ts.api.icsFetch = &http.Client{Timeout: 10 * time.Second}
+
+	user, err := ts.db.UserByEmail(t.Context(), "[email protected]")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// Tilføjet under sin adresse, som er alt der er at gå efter, før den er hentet.
+	if _, err := ts.db.SubscribeCalendar(t.Context(), user.ID, feed.URL, feed.URL); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := ts.api.syncSubscriptions(t.Context(), user); err != nil {
+		t.Fatal(err)
+	}
+	if hits == 0 {
+		t.Fatal("adressen blev aldrig hentet")
+	}
+
+	// Navnet kommer fra filen. X-WR-CALNAME er det, alle udgivere bruger; der
+	// findes ingen standardegenskab for det.
+	_, status := ts.do(t, "GET", "/api/v1/calendar", nil)
+	subs, _ := status["subscriptions"].([]any)
+	if len(subs) != 1 {
+		t.Fatalf("%d abonnementer i svaret", len(subs))
+	}
+	first, _ := subs[0].(map[string]any)
+	if first["account"] != "Helligdage" {
+		t.Errorf("navnet er %v, want Helligdage", first["account"])
+	}
+
+	// Og begivenheden står i gitteret.
+	from := time.Now().AddDate(0, 0, -1).Format("2006-01-02")
+	to := time.Now().AddDate(0, 0, 7).Format("2006-01-02")
+	_, events := ts.do(t, "GET", "/api/v1/calendar/events?from="+from+"&to="+to, nil)
+	list, _ := events["events"].([]any)
+	if len(list) != 1 {
+		t.Fatalf("%d begivenheder efter abonnementet", len(list))
+	}
+	if e, _ := list[0].(map[string]any); e["summary"] != "Grundlovsdag" {
+		t.Errorf("begivenheden er %v", e["summary"])
+	}
+
+	// Den samme adresse to gange er den samme kalender hentet to gange, og der er
+	// ingen måde at sige hvilken der gælder.
+	if _, err := ts.db.SubscribeCalendar(t.Context(), user.ID, feed.URL, ""); !errors.Is(err, store.ErrDuplicate) {
+		t.Errorf("den samme adresse blev accepteret to gange: %v", err)
+	}
+
+	// Fjernet igen, og begivenhederne går med.
+	resp, _ := ts.do(t, "DELETE", "/api/v1/calendar/subscriptions/"+first["id"].(string), nil)
+	if resp.StatusCode != http.StatusNoContent {
+		t.Fatalf("unsubscribe: status %d", resp.StatusCode)
+	}
+	_, events = ts.do(t, "GET", "/api/v1/calendar/events?from="+from+"&to="+to, nil)
+	if list, _ := events["events"].([]any); len(list) != 0 {
+		t.Errorf("%d begivenheder blev tilbage efter afmeldingen", len(list))
+	}
+}
+
+// webcal:// er https med et andet skema foran. Det er ikke en protokol, noget
+// taler — det er en konvention, der får et skrivebord til at give adressen til
+// kalenderprogrammet i stedet for til browseren, og alle udgivere skriver deres
+// links sådan. At afvise den ville være at afvise folk på en teknikalitet.
+func TestWebcalIsRewrittenToHTTPS(t *testing.T) {
+	got, err := normaliseCalendarURL("webcal://example.dk/kalender.ics")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if got != "https://example.dk/kalender.ics" {
+		t.Errorf("blev til %q", got)
+	}
+
+	// Og en adresse indad afvises, hvor den skrives — ikke først når den hentes.
+	if _, err := normaliseCalendarURL("http://127.0.0.1:8080/x.ics"); err == nil {
+		t.Error("en loopback-adresse blev godtaget")
+	}
+	if _, err := normaliseCalendarURL("file:///etc/passwd"); err == nil {
+		t.Error("et skema, der ikke er http, blev godtaget")
+	}
+}

internal/httpapi/mailbox_handlers.go

@@ -143,7 +143,7 @@ func (s *Server) SyncMailbox(ctx context.Context, user *store.User, m *store.Mai
 	// One reader of this mailbox at a time. Held for the whole run, marker and all:
 	// releasing before the marker is written would leave exactly the gap this is
 	// here to close.
-	unlock := s.lockMailbox(m.ID)
+	unlock := s.lockSync(m.ID)
 	defer unlock()
 
 	// Re-read under the lock. The row that came in may have been fetched before the
@@ -175,6 +175,10 @@ func (s *Server) SyncMailbox(ctx context.Context, user *store.User, m *store.Mai
 
 	created := 0
 	highest := m.LastUID
+	// The uids of the mails that actually became tasks. Only those get unflagged,
+	// and only after the task is committed: a flag removed from a mail whose task
+	// was never written is a mail nobody will ever see again.
+	done := make([]uint32, 0, len(messages))
 	for _, msg := range messages {
 		if ctx.Err() != nil {
 			// What was made so far is already committed and counted, and the marker
@@ -204,12 +208,27 @@ func (s *Server) SyncMailbox(ctx context.Context, user *store.User, m *store.Mai
 			continue
 		}
 		created++
+		done = append(done, msg.UID)
 		if msg.UID > highest {
 			highest = msg.UID
 		}
 		s.hub.Publish(projectID, "task.created", toTaskJSON(*task))
 	}
 
+	// The flag comes off what became a task. This is what actually stops a mail
+	// arriving twice; the marker below is now a second line rather than the only
+	// one. See imap.Unflag for why the record belongs in the mailbox and not here.
+	//
+	// Outside the request's context, like the marker: a cancelled request that
+	// already created tasks must still take the flags off them, or the next run
+	// makes them all again.
+	if err := client.Unflag(done); err != nil {
+		// Not fatal, and not the caller's problem. A folder somebody opened
+		// read-only, or a server that refuses the STORE, still gets the uid marker
+		// underneath — worse, but not broken.
+		s.log.Warn("could not unflag imported mail", "err", err, "mailbox", m.ID, "count", len(done))
+	}
+
 	// A run that got all the way through moves the marker to the whole of what the
 	// search considered, not merely to the last message it happened to read. That
 	// is what stops the same mail becoming a task again on the next run when the
@@ -231,8 +250,14 @@ func (s *Server) SyncMailbox(ctx context.Context, user *store.User, m *store.Mai
 	return created, nil
 }
 
-// lockMailbox serialises one mailbox against itself and returns the release.
-func (s *Server) lockMailbox(id string) func() {
+// lockSync serialises one thing that polls against itself and returns the release.
+//
+// A mailbox to begin with; a calendar connection now takes the same lock under a
+// key of its own. Two runs at once — somebody pressing "fetch now" while the sweep
+// is in the middle of the same thing — both start from the state as it was, and
+// the loser writes last. For a mailbox that made forty copies of one mail in a
+// second; for a calendar it would be a window deleted after it was refilled.
+func (s *Server) lockSync(id string) func() {
 	value, _ := s.syncing.LoadOrStore(id, &sync.Mutex{})
 	mu := value.(*sync.Mutex)
 	mu.Lock()

internal/httpapi/mcp_handlers.go

@@ -101,6 +101,7 @@ func (s *Server) buildMCP() *mcp.Server {
 		}, "task_id", "body"),
 	}, s.mcpAddComment)
 
+	s.registerNoteTools(m)
 	return m
 }
 
@@ -496,3 +497,168 @@ func clamp(value, fallback, max int) int {
 	}
 	return value
 }
+
+// --- notes ---------------------------------------------------------------------
+
+// registerNoteTools adds the note half of the MCP surface.
+//
+// Separate from the task tools for one reason worth stating: this is how a note
+// gets in from somewhere else. Apple Notes has no export worth the name, but a
+// model running on the machine can read Notes.app and write what it finds through
+// these — one note at a time, with the text as Markdown. That is a migration
+// nobody has to build a parser for.
+func (s *Server) registerNoteTools(m *mcp.Server) {
+	m.Register(mcp.Tool{
+		Name: "search_notes",
+		Description: "Find notes by text. Matches title and body, and is generous about " +
+			"Danish spelling — searching \"gron\" finds \"grøn\", and the other way round. " +
+			"With no query it returns the most recent notes. This is the tool for " +
+			"\"what did I write about the tax return\" or \"find my note on the kitchen\".",
+		InputSchema: mcp.Schema(map[string]any{
+			"text":  mcp.Str("Words to look for in the title and body."),
+			"limit": mcp.Int("How many to return. Defaults to 25, maximum 100."),
+		}),
+	}, s.mcpSearchNotes)
+
+	m.Register(mcp.Tool{
+		Name: "create_note",
+		Description: "Write a note. The body is Markdown and is stored as typed — it is " +
+			"also exactly what an export produces, so nothing is converted and nothing " +
+			"is lost. Two things in the text are read out of it and become links: " +
+			"`#Projekt` files the note against that project, so it appears on the " +
+			"project's page without anybody filing it there, and `[[Another note]]` " +
+			"links to a note by its title. Use this to bring notes in from elsewhere — " +
+			"Apple Notes, OneNote, a folder of Markdown — one call per note.",
+		InputSchema: mcp.Schema(map[string]any{
+			"body":       mcp.Str("The note as Markdown. Its first line becomes the title, so start with one. #Projekt and [[note]] become links."),
+			"project_id": mcp.Str("File it under a project by id. Usually unnecessary — a #tag in the body does the same and is what a person would type."),
+			"pinned":     mcp.Bool("Keep it at the top of the list."),
+		}),
+	}, s.mcpCreateNote)
+
+	m.Register(mcp.Tool{
+		Name: "update_note",
+		Description: "Change a note. Only the fields given are changed. Sending `body` " +
+			"replaces the whole text, so read the note first if you mean to add to it — " +
+			"and the links are read again from the new text, so a #tag removed is a link " +
+			"removed.",
+		InputSchema: mcp.Schema(map[string]any{
+			"note_id": mcp.Str("Which note."),
+			"body":    mcp.Str("The whole new text, as Markdown. The title follows its first line."),
+			"pinned":  mcp.Bool("Pin it or unpin it."),
+		}),
+	}, s.mcpUpdateNote)
+}
+
+func (s *Server) mcpSearchNotes(ctx context.Context, userID string, args json.RawMessage) (any, error) {
+	var params struct {
+		Text  string `json:"text"`
+		Limit int    `json:"limit"`
+	}
+	_ = json.Unmarshal(args, &params)
+
+	limit := params.Limit
+	if limit <= 0 || limit > 100 {
+		limit = 25
+	}
+
+	var notes []store.Note
+	var err error
+	if strings.TrimSpace(params.Text) == "" {
+		notes, err = s.db.LooseNotes(ctx, userID)
+	} else {
+		notes, err = s.db.SearchNotes(ctx, params.Text, limit)
+	}
+	if err != nil {
+		return nil, err
+	}
+
+	// The same filter the HTTP surface applies, for the same reason: a search must
+	// not become a way to read what you cannot open.
+	out := make([]map[string]any, 0, len(notes))
+	for _, n := range notes {
+		if !s.mcpMayRead(ctx, &n, userID) {
+			continue
+		}
+		out = append(out, map[string]any{
+			"id": n.ID, "title": n.Title, "body": n.Body,
+			"project_id": n.ProjectID, "updated_at": n.UpdatedAt,
+		})
+		if len(out) >= limit {
+			break
+		}
+	}
+	return map[string]any{"notes": out, "count": len(out)}, nil
+}
+
+func (s *Server) mcpMayRead(ctx context.Context, n *store.Note, userID string) bool {
+	if n.ProjectID == "" {
+		return n.CreatedBy == userID
+	}
+	_, err := store.RequireProjectRole(ctx, s.db, n.ProjectID, userID, store.RoleViewer)
+	return err == nil
+}
+
+func (s *Server) mcpCreateNote(ctx context.Context, userID string, args json.RawMessage) (any, error) {
+	var params struct {
+		Body      string `json:"body"`
+		ProjectID string `json:"project_id"`
+		Pinned    bool   `json:"pinned"`
+	}
+	_ = json.Unmarshal(args, &params)
+
+	n := &store.Note{
+		CreatedBy: userID,
+		Body:      params.Body,
+		Pinned:    params.Pinned,
+	}
+	if params.ProjectID != "" {
+		if _, err := store.RequireProjectRole(ctx, s.db, params.ProjectID, userID, store.RoleEditor); err != nil {
+			return nil, err
+		}
+		n.ProjectID = params.ProjectID
+	}
+	if err := s.db.SaveNote(ctx, n); err != nil {
+		return nil, err
+	}
+
+	// The links are reported back rather than left silent. A note whose #tag was
+	// misspelt looks identical to one whose tag landed, and in a chat nobody sees
+	// the row that was written.
+	return map[string]any{
+		"id": n.ID, "title": n.Title, "links": n.Links,
+	}, nil
+}
+
+func (s *Server) mcpUpdateNote(ctx context.Context, userID string, args json.RawMessage) (any, error) {
+	var params struct {
+		NoteID string  `json:"note_id"`
+		Body   *string `json:"body"`
+		Pinned *bool   `json:"pinned"`
+	}
+	_ = json.Unmarshal(args, &params)
+
+	n, err := s.db.Note(ctx, params.NoteID)
+	if err != nil {
+		return nil, err
+	}
+	if n == nil || !s.mcpMayRead(ctx, n, userID) {
+		return nil, fmt.Errorf("no such note")
+	}
+	if n.ProjectID != "" {
+		if _, err := store.RequireProjectRole(ctx, s.db, n.ProjectID, userID, store.RoleEditor); err != nil {
+			return nil, err
+		}
+	}
+
+	if params.Body != nil {
+		n.Body = *params.Body
+	}
+	if params.Pinned != nil {
+		n.Pinned = *params.Pinned
+	}
+	if err := s.db.SaveNote(ctx, n); err != nil {
+		return nil, err
+	}
+	return map[string]any{"id": n.ID, "title": n.Title, "links": n.Links}, nil
+}

internal/httpapi/notes_handlers.go

@@ -0,0 +1,807 @@
+package httpapi
+
+import (
+	"archive/zip"
+	"fmt"
+	"io"
+	"mime"
+	"net/http"
+	"os"
+	"path"
+	"path/filepath"
+	"sort"
+	"strings"
+	"time"
+
+	"github.com/go-chi/chi/v5"
+	"github.com/kristianwind/verdande/internal/store"
+)
+
+// Notes.
+//
+// Access follows the project, because that is where a note lives: a note in a
+// shared project is readable by everybody who can read the project and writable
+// by an editor. A note with no project is its author's alone — the same answer a
+// task in the inbox gets, arrived at the same way rather than by a rule of its own.
+
+// mayReadNote reports whether this person may see the note, and mayWriteNote
+// whether they may change it. Split, because a viewer on a shared project can do
+// the first and not the second.
+func (s *Server) mayTouchNote(r *http.Request, n *store.Note, role store.Role) bool {
+	user := userFrom(r.Context())
+	if n.ProjectID == "" {
+		return n.CreatedBy == user.ID
+	}
+	_, err := store.RequireProjectRole(r.Context(), s.db, n.ProjectID, user.ID, role)
+	return err == nil
+}
+
+func (s *Server) handleListNotes(w http.ResponseWriter, r *http.Request) {
+	user := userFrom(r.Context())
+
+	// Searching and listing are the same endpoint, because they answer the same
+	// question with different words. ?q= searches; ?project= narrows; neither gives
+	// the loose ones.
+	if q := strings.TrimSpace(r.URL.Query().Get("q")); q != "" {
+		found, err := s.db.SearchNotes(r.Context(), q, 50)
+		if err != nil {
+			s.internal(w, r, "search notes", err)
+			return
+		}
+		writeJSON(w, http.StatusOK, map[string]any{"notes": briefly(s.readable(r, found))})
+		return
+	}
+
+	if projectID := r.URL.Query().Get("project"); projectID != "" {
+		if _, err := store.RequireProjectRole(r.Context(), s.db, projectID, user.ID, store.RoleViewer); err != nil {
+			s.storeError(w, r, "notes in project", err)
+			return
+		}
+		found, err := s.db.NotesInProject(r.Context(), projectID)
+		if err != nil {
+			s.internal(w, r, "notes in project", err)
+			return
+		}
+		writeJSON(w, http.StatusOK, map[string]any{"notes": briefly(found)})
+		return
+	}
+
+	// The archive is the same list asked the other way round, so it is the same
+	// endpoint with a flag rather than a second one that would have to be kept in
+	// step with this.
+	if r.URL.Query().Get("archived") != "" {
+		found, err := s.db.ArchivedNotes(r.Context(), user.ID)
+		if err != nil {
+			s.internal(w, r, "list archived notes", err)
+			return
+		}
+		writeJSON(w, http.StatusOK, map[string]any{"notes": briefly(found)})
+		return
+	}
+
+	// Everything they can see, not only the loose ones. Filing a note in a project
+	// is how it gets shared, and a list that dropped it at that moment made sharing
+	// look like deleting.
+	found, err := s.db.AllNotes(r.Context(), user.ID)
+	if err != nil {
+		s.internal(w, r, "list notes", err)
+		return
+	}
+	writeJSON(w, http.StatusOK, map[string]any{"notes": briefly(found)})
+}
+
+// briefly replaces each note's body with the first of it.
+//
+// The list shows a title and about ninety characters. It was being sent whole
+// notes to do that: with twelve hundred of them the response was 845 KB, of which
+// ninety-eight per cent was body text nobody would read on that screen — fetched,
+// parsed and held in memory on every visit.
+//
+// Body is emptied rather than shortened, and that is the important half. A field
+// called `body` that holds a *piece* of the body is a trap: the editor would open
+// it, the debounce would save it, and the note would be cut down to its own
+// preview by nothing more than being looked at. Empty is a shape the client can
+// check, and it does — see the notes page, which fetches the whole note when it
+// opens one.
+//
+// Four hundred characters rather than ninety: the client strips Markdown before
+// it shows anything, and a heading marker and a bold word are characters that
+// vanish. Cheap insurance against a preview that ends up shorter than the line it
+// is meant to fill.
+const previewChars = 400
+
+func briefly(notes []store.Note) []store.Note {
+	out := make([]store.Note, 0, len(notes))
+	for _, n := range notes {
+		body := []rune(n.Body)
+		if len(body) > previewChars {
+			body = body[:previewChars]
+		}
+		n.Preview = string(body)
+		n.Body = ""
+		out = append(out, n)
+	}
+	return out
+}
+
+// readable drops what this person may not see.
+//
+// Filtered after the search rather than inside it: FTS5 answers about text, and
+// teaching the index about roles would put an access rule in a place nobody would
+// think to look when it was wrong.
+func (s *Server) readable(r *http.Request, notes []store.Note) []store.Note {
+	out := make([]store.Note, 0, len(notes))
+	for _, n := range notes {
+		if s.mayTouchNote(r, &n, store.RoleViewer) {
+			out = append(out, n)
+		}
+	}
+	return out
+}
+
+func (s *Server) handleGetNote(w http.ResponseWriter, r *http.Request) {
+	n, err := s.db.Note(r.Context(), chi.URLParam(r, "noteID"))
+	if err != nil {
+		s.internal(w, r, "get note", err)
+		return
+	}
+	// The same answer for "no such note" and "not yours", so an id cannot be probed.
+	if n == nil || !s.mayTouchNote(r, n, store.RoleViewer) {
+		writeError(w, http.StatusNotFound, CodeNotFound, "no such note")
+		return
+	}
+	writeJSON(w, http.StatusOK, n)
+}
+
+// No title. It is the note's first line and is derived on every save — a field
+// here would be a promise this server cannot keep.
+type noteBody struct {
+	ProjectID *string `json:"project_id"`
+	Body      *string `json:"body"`
+	Pinned    *bool   `json:"pinned"`
+}
+
+func (s *Server) handleCreateNote(w http.ResponseWriter, r *http.Request) {
+	var body noteBody
+	if err := decodeJSON(w, r, &body); err != nil {
+		return
+	}
+	user := userFrom(r.Context())
+
+	n := &store.Note{CreatedBy: user.ID}
+	if body.ProjectID != nil && *body.ProjectID != "" {
+		if _, err := store.RequireProjectRole(r.Context(), s.db, *body.ProjectID, user.ID, store.RoleEditor); err != nil {
+			s.storeError(w, r, "create note", err)
+			return
+		}
+		n.ProjectID = *body.ProjectID
+	}
+	if body.Body != nil {
+		n.Body = *body.Body
+	}
+	if body.Pinned != nil {
+		n.Pinned = *body.Pinned
+	}
+
+	if err := s.db.SaveNote(r.Context(), n); err != nil {
+		s.internal(w, r, "create note", err)
+		return
+	}
+	writeJSON(w, http.StatusCreated, n)
+}
+
+func (s *Server) handleUpdateNote(w http.ResponseWriter, r *http.Request) {
+	var body noteBody
+	if err := decodeJSON(w, r, &body); err != nil {
+		return
+	}
+
+	n, err := s.db.Note(r.Context(), chi.URLParam(r, "noteID"))
+	if err != nil {
+		s.internal(w, r, "update note", err)
+		return
+	}
+	if n == nil || !s.mayTouchNote(r, n, store.RoleEditor) {
+		writeError(w, http.StatusNotFound, CodeNotFound, "no such note")
+		return
+	}
+
+	if body.ProjectID != nil {
+		// Moving it means being allowed on both sides: you cannot file somebody
+		// else's note into your project, nor yours into theirs.
+		if *body.ProjectID != "" {
+			if _, err := store.RequireProjectRole(r.Context(), s.db, *body.ProjectID,
+				userFrom(r.Context()).ID, store.RoleEditor); err != nil {
+				s.storeError(w, r, "move note", err)
+				return
+			}
+		}
+		n.ProjectID = *body.ProjectID
+	}
+	if body.Body != nil {
+		n.Body = *body.Body
+	}
+	if body.Pinned != nil {
+		n.Pinned = *body.Pinned
+	}
+
+	if err := s.db.SaveNote(r.Context(), n); err != nil {
+		s.internal(w, r, "update note", err)
+		return
+	}
+	writeJSON(w, http.StatusOK, n)
+}
+
+func (s *Server) handleDeleteNote(w http.ResponseWriter, r *http.Request) {
+	n, err := s.db.Note(r.Context(), chi.URLParam(r, "noteID"))
+	if err != nil {
+		s.internal(w, r, "delete note", err)
+		return
+	}
+	if n == nil || !s.mayTouchNote(r, n, store.RoleEditor) {
+		writeError(w, http.StatusNotFound, CodeNotFound, "no such note")
+		return
+	}
+	if err := s.db.DeleteNote(r.Context(), n.ID); err != nil {
+		s.internal(w, r, "delete note", err)
+		return
+	}
+	w.WriteHeader(http.StatusNoContent)
+}
+
+// handleNotesLinking answers the backwards question for a task or a project:
+// what has somebody written about this.
+func (s *Server) handleNotesLinking(w http.ResponseWriter, r *http.Request) {
+	kind := chi.URLParam(r, "kind")
+	if kind != "task" && kind != "project" && kind != "note" {
+		writeError(w, http.StatusBadRequest, CodeValidation, "kind must be task, project or note")
+		return
+	}
+	found, err := s.db.NotesLinking(r.Context(), kind, chi.URLParam(r, "targetID"))
+	if err != nil {
+		s.internal(w, r, "notes linking", err)
+		return
+	}
+	writeJSON(w, http.StatusOK, map[string]any{"notes": s.readable(r, found)})
+}
+
+// handleExportNotes writes every note this person can see as a zip of Markdown
+// files, one per note.
+//
+// A zip of plain files rather than one bundle in a format of our own: what comes
+// out is what was stored, and it opens in Obsidian, in a text editor, in anything.
+// That is the promise the whole design was arranged around — the note on disk is
+// already the file you would export — and this is where it is either kept or not.
+func (s *Server) handleExportNotes(w http.ResponseWriter, r *http.Request) {
+	user := userFrom(r.Context())
+	notes, err := s.db.AllNotes(r.Context(), user.ID)
+	if err != nil {
+		s.internal(w, r, "export notes", err)
+		return
+	}
+
+	w.Header().Set("Content-Type", "application/zip")
+	w.Header().Set("Content-Disposition",
+		`attachment; filename="verdande-noter-`+time.Now().Format("2006-01-02")+`.zip"`)
+
+	zw := zip.NewWriter(w)
+	defer zw.Close()
+
+	// Names collide: two notes called "Møde" are two notes, and a zip with one entry
+	// twice is a zip that loses one of them.
+	used := map[string]int{}
+	for _, n := range notes {
+		name := noteFilename(n.Title)
+		used[name]++
+		if used[name] > 1 {
+			name = fmt.Sprintf("%s (%d)", name, used[name])
+		}
+
+		f, err := zw.CreateHeader(&zip.FileHeader{
+			Name:     name + ".md",
+			Method:   zip.Deflate,
+			Modified: n.UpdatedAt,
+		})
+		if err != nil {
+			// The response is already streaming, so there is no status left to send.
+			// Stopping leaves a truncated zip, which a zip tool says is truncated —
+			// better than a complete-looking file with a note missing from it.
+			s.log.Error("export notes", "err", err, "note", n.ID)
+			return
+		}
+		if _, err := io.WriteString(f, n.Body); err != nil {
+			s.log.Error("export notes", "err", err, "note", n.ID)
+			return
+		}
+	}
+}
+
+// noteFilename makes a title safe to be a filename on any of the three systems
+// people actually use, without turning it into something unrecognisable.
+func noteFilename(title string) string {
+	name := strings.TrimSpace(title)
+	if name == "" {
+		name = "uden titel"
+	}
+	// Windows refuses these outright; a slash would make directories on the others.
+	name = strings.Map(func(r rune) rune {
+		if strings.ContainsRune(`/\:*?"<>|`, r) || r < 0x20 {
+			return '-'
+		}
+		return r
+	}, name)
+	// Long titles are the first line of a note, which can be a whole sentence.
+	if len([]rune(name)) > 80 {
+		name = string([]rune(name)[:80])
+	}
+	return strings.TrimRight(name, " .")
+}
+
+// maxNoteImportBytes bounds one upload. Generous for text — a decade of notes is
+// a few megabytes — and small enough that a wrong file is refused rather than read.
+const maxNoteImportBytes = 64 << 20
+
+// What the archive may become once it is unpacked, and how many entries it may
+// hold. See handleImportNotes: the upload cap bounds what arrives, and says
+// nothing at all about what it expands to.
+const (
+	maxNoteImportUnpacked = 2 << 30
+	maxNoteImportFiles    = 20_000
+)
+
+// handleImportNotes reads a zip of Markdown files and makes a note of each.
+//
+// The mirror of the export, and deliberately the same shape: whatever comes out of
+// this program goes back into it. It is also the way in from anywhere else, since
+// a folder of Markdown is what Obsidian, Bear, iA Writer and a shell script all
+// produce — and what the Apple Notes exporter in tools/ writes.
+//
+// Filenames are ignored. The title is the first line of the body, everywhere else
+// in this program, and making it the filename here would be a second rule for the
+// same thing that disagrees the moment somebody renames a file.
+func (s *Server) handleImportNotes(w http.ResponseWriter, r *http.Request) {
+	r.Body = http.MaxBytesReader(w, r.Body, maxNoteImportBytes)
+	if err := r.ParseMultipartForm(4 << 20); err != nil {
+		writeError(w, http.StatusRequestEntityTooLarge, CodePayloadTooLarge, "the file is too large")
+		return
+	}
+	defer r.MultipartForm.RemoveAll()
+
+	file, header, err := r.FormFile("file")
+	if err != nil {
+		writeFieldErrors(w, map[string]string{"file": "required"})
+		return
+	}
+	defer file.Close()
+
+	zr, err := zip.NewReader(file.(io.ReaderAt), header.Size)
+	if err != nil {
+		writeFieldErrors(w, map[string]string{"file": "not a zip archive"})
+		return
+	}
+
+	user := userFrom(r.Context())
+	created, skipped, files := 0, 0, 0
+
+	// Two passes. Everything that is not Markdown is stored first, so that when a
+	// note is read its pictures already have addresses to be rewritten to — a note
+	// and its images arrive in whatever order the archive happens to hold them, and
+	// one pass would leave half the links pointing at nothing.
+	// The archive as a whole, not just the upload.
+	//
+	// The 64 MB cap is on what arrives; deflate reaches about 1032:1, so those 64
+	// MB can become sixty-six gigabytes on the way out — written into the same
+	// volume the database lives on. The upload limit says nothing about that, and
+	// nothing else did either.
+	//
+	// Two ceilings: one per file, and one across the archive. A single enormous
+	// photograph and ten thousand small ones are different attacks with the same
+	// ending.
+	if len(zr.File) > maxNoteImportFiles {
+		writeError(w, http.StatusRequestEntityTooLarge, CodePayloadTooLarge,
+			"that archive holds too many files")
+		return
+	}
+	budget := int64(maxNoteImportUnpacked)
+
+	stored := map[string]string{}
+	for _, f := range zr.File {
+		name := f.Name
+		if f.FileInfo().IsDir() || skipFile(name) || strings.EqualFold(path.Ext(name), ".md") {
+			continue
+		}
+		// The header's own claim first, which costs nothing to check and rejects
+		// the obvious case before a byte is written. It is only a claim, so the
+		// reader below is limited as well.
+		if f.UncompressedSize64 > maxUploadBytes {
+			s.log.Warn("import: a file in the archive is too large", "file", name)
+			skipped++
+			continue
+		}
+		rc, err := f.Open()
+		if err != nil {
+			continue
+		}
+		hashed, size, err := s.storeUpload(io.LimitReader(rc, min(budget, maxUploadBytes)+1))
+		rc.Close()
+		if err != nil {
+			s.log.Warn("import note file", "err", err, "file", name)
+			continue
+		}
+		if size > maxUploadBytes || size > budget {
+			// Over the line once it was actually read: remove what was written
+			// rather than keeping a truncated file that would open as nothing.
+			os.Remove(filepath.Join(s.cfg.FilesDir(), hashed))
+			s.log.Warn("import: archive is larger unpacked than allowed", "file", name)
+			skipped++
+			continue
+		}
+		budget -= size
+		stored[name] = hashed
+		files++
+	}
+
+	for _, f := range zr.File {
+		name := f.Name
+		if f.FileInfo().IsDir() || !strings.EqualFold(path.Ext(name), ".md") {
+			continue
+		}
+		// Counted, not passed over in silence. A Markdown file the filter refuses is
+		// a note that did not arrive, and the caller is told the same number either
+		// way unless it is said here — which is how one note went missing without
+		// anything looking wrong.
+		if skipFile(name) {
+			s.log.Warn("import skipped a note file", "file", name)
+			skipped++
+			continue
+		}
+
+		rc, err := f.Open()
+		if err != nil {
+			skipped++
+			continue
+		}
+		body, err := io.ReadAll(io.LimitReader(rc, 2<<20))
+		rc.Close()
+		if err != nil || strings.TrimSpace(string(body)) == "" {
+			skipped++
+			continue
+		}
+
+		text, wrote, changed := readFrontMatter(string(body))
+
+		n := &store.Note{CreatedBy: user.ID, Body: text}
+		if err := s.db.SaveNote(r.Context(), n); err != nil {
+			s.log.Warn("import note", "err", err, "file", name)
+			skipped++
+			continue
+		}
+
+		// After the save, not as part of it: SaveNote owns `updated_at` and is right
+		// to, so the dates a note had before this program existed are written over
+		// the top rather than passed through it.
+		if !wrote.IsZero() || !changed.IsZero() {
+			if err := s.db.SetNoteTimes(r.Context(), n.ID, wrote, changed); err != nil {
+				s.log.Warn("import note dates", "err", err, "file", name)
+			}
+		}
+
+		// The pictures the note referred to, now that it has an id to hang them on.
+		// The text is rewritten to the addresses they were given, so an image that
+		// sat in the middle of a paragraph is still in the middle of it.
+		if rewritten, attached := s.attachToNote(r, n, path.Dir(name), stored, zr); attached > 0 {
+			n.Body = rewritten
+			if err := s.db.SaveNote(r.Context(), n); err != nil {
+				s.log.Warn("rewrite note links", "err", err, "note", n.ID)
+			}
+		}
+		created++
+	}
+
+	writeJSON(w, http.StatusOK, map[string]any{
+		"created": created, "skipped": skipped, "files": files,
+	})
+}
+
+// skipFile is the things in an archive that are not content: directories' own
+// entries, macOS resource forks, and anything trying to climb out of the archive.
+// A zip made on a Mac carries a __MACOSX copy of every file, and importing those
+// would double a whole library with each copy full of binary rubbish.
+func skipFile(name string) bool {
+	if strings.HasPrefix(name, "__MACOSX/") ||
+		strings.HasPrefix(path.Base(name), "._") ||
+		strings.HasPrefix(path.Base(name), ".") {
+		return true
+	}
+
+	// Traversal, read as path segments rather than as a substring.
+	//
+	// This was `strings.Contains(name, "..")`, which is the right idea aimed at the
+	// wrong thing: it does not describe a path that climbs out of the archive, it
+	// describes any name with two dots next to each other anywhere in it. A note
+	// called "Så blev det endelig jul! Stay tuned... ☕️" was therefore dropped —
+	// silently, and without even counting as skipped, so the number the import
+	// reported still looked right. One note in twelve hundred, found only by
+	// counting what came out.
+	//
+	// An ellipsis in a title is ordinary. A segment that *is* "..", or a path that
+	// starts at the root, is not — and those are what a zip uses to write outside
+	// the folder it was unpacked into.
+	if strings.HasPrefix(name, "/") {
+		return true
+	}
+	for _, part := range strings.Split(name, "/") {
+		if part == ".." {
+			return true
+		}
+	}
+	return false
+}
+
+// attachToNote records the files a note's text points at and rewrites the text to
+// where they now live. Returns the new body and how many were attached.
+//
+// Only the files this note refers to. An archive is one folder for many notes, and
+// hanging every picture on every note would turn a library of a hundred into ten
+// thousand attachments.
+func (s *Server) attachToNote(
+	r *http.Request, n *store.Note, dir string, stored map[string]string, zr *zip.Reader,
+) (string, int) {
+	body := n.Body
+	attached := 0
+
+	for _, f := range zr.File {
+		hashed, ok := stored[f.Name]
+		if !ok {
+			continue
+		}
+		base := path.Base(f.Name)
+		// The three ways a Markdown file names a neighbouring image: by its path
+		// inside the archive, by the path relative to the note, and by its bare name.
+		//
+		// The archive path was missing, and it is the one an Apple Notes export
+		// actually writes — `vedhaeftninger/751-2-IMG_0615.heic`, with the note at the
+		// root beside the folder. Only the bare name matched, so only the bare name
+		// was replaced, and every picture in every imported note ended up pointing at
+		// `vedhaeftninger//api/v1/attachments/…`, which is nothing. The images were
+		// stored and attached correctly; it was the link that was wrong.
+		relative := strings.TrimPrefix(path.Join(dir, base), "./")
+		refs := []string{f.Name, relative, base}
+		if !strings.Contains(body, f.Name) &&
+			!strings.Contains(body, relative) &&
+			!strings.Contains(body, base) {
+			continue
+		}
+
+		a := &store.Attachment{
+			NoteID:     n.ID,
+			Filename:   base,
+			MimeType:   mimeOf(base),
+			Size:       int64(f.UncompressedSize64),
+			Path:       hashed,
+			UploadedBy: n.CreatedBy,
+		}
+		if err := s.db.CreateAttachment(r.Context(), a); err != nil {
+			s.log.Warn("attach to note", "err", err, "file", base)
+			continue
+		}
+
+		// Længste først. Erstattes det bare navn inde i en længere sti, bliver mappen
+		// stående foran adressen, og linket peger på ingenting.
+		url := "/api/v1/attachments/" + a.ID
+		sort.Slice(refs, func(i, j int) bool { return len(refs[i]) > len(refs[j]) })
+		for _, ref := range refs {
+			if ref != "" {
+				body = strings.ReplaceAll(body, ref, url)
+			}
+		}
+		attached++
+	}
+	return body, attached
+}
+
+// readFrontMatter takes the YAML block off the top of a Markdown file and reads
+// the two dates out of it, returning the rest of the text.
+//
+// Not a YAML parser, and deliberately not: the block this reads is the one this
+// program writes, plus whatever Obsidian and Bear write, and all of them use the
+// same handful of `key: value` lines. Pulling in a parser to read two dates would
+// be a dependency that can fail in ways nobody here would recognise.
+//
+// A file with no front matter comes back untouched — that is the normal case, and
+// it must never lose its first line to a rule about a block that is not there.
+func readFrontMatter(body string) (text string, created, modified time.Time) {
+	if !strings.HasPrefix(body, "---\n") && !strings.HasPrefix(body, "---\r\n") {
+		return body, time.Time{}, time.Time{}
+	}
+	rest := body[strings.Index(body, "\n")+1:]
+
+	end := strings.Index(rest, "\n---")
+	if end < 0 {
+		// An opening fence with no close is not front matter; it is a horizontal
+		// rule somebody wrote at the top of their note.
+		return body, time.Time{}, time.Time{}
+	}
+	block := rest[:end]
+	after := rest[end+len("\n---"):]
+	after = strings.TrimPrefix(after, "\r")
+	after = strings.TrimPrefix(after, "\n")
+
+	for _, line := range strings.Split(block, "\n") {
+		key, value, ok := strings.Cut(line, ":")
+		if !ok {
+			continue
+		}
+		value = strings.TrimSpace(strings.Trim(strings.TrimSpace(value), `"'`))
+		switch strings.ToLower(strings.TrimSpace(key)) {
+		case "created", "created_at", "date":
+			created = parseNoteTime(value)
+		case "modified", "updated", "updated_at":
+			modified = parseNoteTime(value)
+		}
+	}
+	return strings.TrimLeft(after, "\n"), created, modified
+}
+
+// parseNoteTime accepts the shapes these files actually carry. A date without a
+// time is that day at midnight, local — the note was written on that day, and
+// pretending to know the hour would be worse than not having one.
+func parseNoteTime(v string) time.Time {
+	for _, layout := range []string{
+		time.RFC3339,
+		"2006-01-02T15:04:05",
+		"2006-01-02 15:04:05",
+		"2006-01-02 15:04",
+		"2006-01-02",
+	} {
+		if t, err := time.ParseInLocation(layout, v, time.Local); err == nil {
+			return t
+		}
+	}
+	return time.Time{}
+}
+
+// mimeOf guesses from the extension. The archive does not carry a type, and
+// sniffing the bytes would mean reading every file twice.
+func mimeOf(name string) string {
+	if t := mime.TypeByExtension(path.Ext(name)); t != "" {
+		return t
+	}
+	return "application/octet-stream"
+}
+
+// handleUploadNoteAttachment takes a file into a note.
+//
+// The import could already do this, and nothing else could: a note brought in
+// from Apple Notes arrived with its pictures, and a note written here could not
+// be given one. Pasting a screenshot into a note is the most ordinary thing there
+// is, and it did nothing at all.
+//
+// Editor rights on the note, checked the same way every other write to it is. The
+// answer for "no such note" and "not yours" is the same, so an id cannot be
+// probed by watching which one comes back.
+func (s *Server) handleUploadNoteAttachment(w http.ResponseWriter, r *http.Request) {
+	n, err := s.db.Note(r.Context(), chi.URLParam(r, "noteID"))
+	if err != nil {
+		s.internal(w, r, "get note", err)
+		return
+	}
+	if n == nil || !s.mayTouchNote(r, n, store.RoleEditor) {
+		writeError(w, http.StatusNotFound, CodeNotFound, "no such note")
+		return
+	}
+
+	r.Body = http.MaxBytesReader(w, r.Body, maxUploadBytes+(1<<20))
+	if err := r.ParseMultipartForm(8 << 20); err != nil {
+		writeError(w, http.StatusRequestEntityTooLarge, CodePayloadTooLarge,
+			"that file is too large (25 MB maximum)")
+		return
+	}
+	defer r.MultipartForm.RemoveAll()
+
+	file, header, err := r.FormFile("file")
+	if err != nil {
+		writeFieldErrors(w, map[string]string{"file": "required"})
+		return
+	}
+	defer file.Close()
+
+	if header.Size > maxUploadBytes {
+		writeError(w, http.StatusRequestEntityTooLarge, CodePayloadTooLarge,
+			"that file is too large (25 MB maximum)")
+		return
+	}
+
+	stored, size, err := s.storeUpload(file)
+	if err != nil {
+		s.internal(w, r, "store upload", err)
+		return
+	}
+
+	user := userFrom(r.Context())
+	a := &store.Attachment{
+		NoteID:     n.ID,
+		Filename:   safeFilename(header.Filename),
+		MimeType:   detectMime(header.Filename, header.Header.Get("Content-Type")),
+		Size:       size,
+		Path:       stored,
+		UploadedBy: user.ID,
+	}
+	if err := s.db.CreateAttachment(r.Context(), a); err != nil {
+		os.Remove(filepath.Join(s.cfg.FilesDir(), stored))
+		s.internal(w, r, "record attachment", err)
+		return
+	}
+	writeJSON(w, http.StatusCreated, toAttachmentJSON(*a))
+}
+
+// --- putting notes away, one or many ---------------------------------------------
+
+type noteBulkRequest struct {
+	IDs      []string `json:"ids"`
+	Archived *bool    `json:"archived"`
+	Delete   bool     `json:"delete"`
+}
+
+// maxNoteBulk bounds one call. Enough to select a screenful several times over,
+// and few enough that the loop below cannot become somebody's afternoon.
+const maxNoteBulk = 500
+
+// handleNoteBulk archives, unarchives or deletes a set of notes in one request.
+//
+// One call rather than one per note, because the thing being asked is one thing:
+// "put these away". Fifty separate requests would be fifty round trips, fifty
+// chances for half of them to fail, and a list that redraws fifty times — and
+// after an import of twelve hundred notes, selecting fifty is the ordinary case,
+// not the extreme one.
+//
+// Each note is still checked on its own. A set is a convenience for the caller
+// and must never become a way to touch something they could not have touched one
+// at a time.
+func (s *Server) handleNoteBulk(w http.ResponseWriter, r *http.Request) {
+	var req noteBulkRequest
+	if err := decodeJSON(w, r, &req); err != nil {
+		return
+	}
+	if len(req.IDs) == 0 {
+		writeFieldErrors(w, map[string]string{"ids": "required"})
+		return
+	}
+	if len(req.IDs) > maxNoteBulk {
+		writeFieldErrors(w, map[string]string{"ids": "too many at once"})
+		return
+	}
+
+	done, skipped := 0, 0
+	for _, id := range req.IDs {
+		n, err := s.db.Note(r.Context(), id)
+		if err != nil {
+			s.internal(w, r, "get note", err)
+			return
+		}
+		// Not an error, and not a 404 for the whole call: a set can contain a note
+		// somebody else deleted a second ago, and the other forty-nine should still
+		// be put away. Counted so the answer is honest about it.
+		if n == nil || !s.mayTouchNote(r, n, store.RoleEditor) {
+			skipped++
+			continue
+		}
+
+		switch {
+		case req.Delete:
+			err = s.db.DeleteNote(r.Context(), id)
+		case req.Archived != nil:
+			err = s.db.SetNoteArchived(r.Context(), id, *req.Archived)
+		default:
+			writeFieldErrors(w, map[string]string{"archived": "say archived or delete"})
+			return
+		}
+		if err != nil {
+			s.internal(w, r, "note bulk", err)
+			return
+		}
+		done++
+	}
+
+	writeJSON(w, http.StatusOK, map[string]any{"done": done, "skipped": skipped})
+}

internal/httpapi/notes_import_filter_test.go

@@ -0,0 +1,38 @@
+package httpapi
+
+import "testing"
+
+// En titel med tre prikker i er ikke et forsøg på at skrive uden for mappen.
+//
+// `strings.Contains(name, "..")` var den rigtige idé rettet mod det forkerte:
+// den beskriver ikke en sti, der klatrer ud af arkivet, men ethvert navn med to
+// prikker ved siden af hinanden. Noten "Så blev det endelig jul! Stay tuned... ☕️"
+// blev derfor droppet lydløst — én ud af tolv hundrede, og kun fundet ved at
+// tælle efter, hvor mange der kom ud.
+func TestSkipFileTakesEllipsesButRefusesTraversal(t *testing.T) {
+	keep := []string{
+		"Så blev det endelig jul! Stay tuned... ☕️.md",
+		"Møde 12.8..md",
+		"vedhaeftninger/1-2-Pasted Graphic.png",
+		"noter/Referat....md",
+	}
+	for _, name := range keep {
+		if skipFile(name) {
+			t.Errorf("skipFile(%q) = true, men det er et almindeligt filnavn", name)
+		}
+	}
+
+	drop := []string{
+		"../uden for.md",
+		"noter/../../etc/passwd",
+		"/etc/passwd",
+		"__MACOSX/._noget",
+		".skjult.md",
+		"noter/._AppleDouble.md",
+	}
+	for _, name := range drop {
+		if !skipFile(name) {
+			t.Errorf("skipFile(%q) = false, men den skal afvises", name)
+		}
+	}
+}

internal/httpapi/notes_import_limits_test.go

@@ -0,0 +1,77 @@
+package httpapi
+
+import (
+	"archive/zip"
+	"bytes"
+	"io"
+	"testing"
+)
+
+// En zip-bombe skal ikke kunne skrive gigabyte ned på den disk, databasen ligger
+// på.
+//
+// Uploaden er begrænset til 64 MB, og det siger ingenting om, hvad de 64 MB
+// bliver til: deflate når omkring 1032:1, så de kan pakkes ud til seksogtres
+// gigabyte. Prøven bygger en rigtig lille bombe — fire megabyte nuller, som
+// pakker til nogle få kilobyte — og ser efter, at loftet på det udpakkede holder.
+//
+// Skrevet imod tallene frem for imod endepunktet, fordi det, der skal holde, er
+// forholdet: en fil, hvis udpakkede størrelse overstiger loftet, må ikke læses
+// færdig.
+func TestAZipBombIsRefusedByItsUnpackedSize(t *testing.T) {
+	var buf bytes.Buffer
+	zw := zip.NewWriter(&buf)
+	w, err := zw.Create("bombe.bin")
+	if err != nil {
+		t.Fatal(err)
+	}
+	// Nuller pakker næsten helt væk. Fire megabyte er nok til at vise forholdet
+	// uden at prøven selv bruger en gigabyte.
+	if _, err := w.Write(make([]byte, 4<<20)); err != nil {
+		t.Fatal(err)
+	}
+	if err := zw.Close(); err != nil {
+		t.Fatal(err)
+	}
+
+	packed := int64(buf.Len())
+	if packed > 64<<10 {
+		t.Fatalf("prøvens egen bombe pakkede kun til %d bytes; den viser ikke noget", packed)
+	}
+
+	zr, err := zip.NewReader(bytes.NewReader(buf.Bytes()), packed)
+	if err != nil {
+		t.Fatal(err)
+	}
+	f := zr.File[0]
+	if f.UncompressedSize64 != 4<<20 {
+		t.Fatalf("udpakket størrelse = %d", f.UncompressedSize64)
+	}
+
+	// Det, importen gør: læs højst det, budgettet tillader, plus én byte — så en
+	// fil, der er præcis på grænsen, kan skelnes fra en, der er over.
+	rc, err := f.Open()
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer rc.Close()
+	budget := int64(1 << 20)
+	n, err := io.Copy(io.Discard, io.LimitReader(rc, budget+1))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if n <= budget {
+		t.Fatalf("læste %d bytes af en fil på 4 MB med et budget på %d — loftet fanger den ikke", n, budget)
+	}
+}
+
+// Tallene skal stå i et forhold, der giver mening: en enkelt fil må aldrig kunne
+// bruge hele arkivets budget, og arkivet må ikke være mindre end én fil.
+func TestTheImportCeilingsAgreeWithEachOther(t *testing.T) {
+	if maxNoteImportUnpacked <= maxUploadBytes {
+		t.Error("arkivets budget er ikke større end én enkelt fil")
+	}
+	if maxNoteImportFiles < 2000 {
+		t.Error("filloftet er under det, en rigtig Apple Noter-eksport indeholder")
+	}
+}

internal/httpapi/notes_test.go

@@ -0,0 +1,373 @@
+package httpapi
+
+import (
+	"archive/zip"
+	"bytes"
+	"encoding/json"
+	"io"
+	"mime/multipart"
+	"net/http"
+	"strings"
+	"testing"
+)
+
+// A note in a project is the project's; a note in no project is its author's.
+// Both answers come from the project's own roles rather than from a rule notes
+// invented for themselves, which is the point of filing them there.
+func TestANoteIsNotReadableByJustAnybody(t *testing.T) {
+	ts := newTestServer(t)
+	ts.bootstrap(t)
+
+	resp, body := ts.do(t, "POST", "/api/v1/notes", map[string]any{
+		"body": "Noget privat om #Firma",
+	})
+	if resp.StatusCode != http.StatusCreated {
+		t.Fatalf("create: %d %v", resp.StatusCode, body)
+	}
+	id, _ := body["id"].(string)
+	if id == "" {
+		t.Fatal("no id came back")
+	}
+
+	// The tags were read out of the text on the way in, without being asked for.
+	links, _ := body["links"].([]any)
+	if len(links) != 1 {
+		t.Fatalf("the note recorded %v", body["links"])
+	}
+
+	// Somebody else gets the same answer as for a note that does not exist, so an
+	// id cannot be probed for existence.
+	other := ts.newUser(t, "[email protected]", "Anden")
+	resp, _ = other.do(t, "GET", "/api/v1/notes/"+id, nil)
+	if resp.StatusCode != http.StatusNotFound {
+		t.Errorf("a stranger got %d for somebody else's note, want 404", resp.StatusCode)
+	}
+}
+
+// Searching must not become a way to read what you cannot open. The filter is
+// applied after the index, and this is what says so.
+func TestSearchDoesNotLeakNotesYouCannotRead(t *testing.T) {
+	ts := newTestServer(t)
+	ts.bootstrap(t)
+
+	if resp, body := ts.do(t, "POST", "/api/v1/notes", map[string]any{
+		"body": "Hemmeligt kodeord til hjemmesiden",
+	}); resp.StatusCode != http.StatusCreated {
+		t.Fatalf("create: %d %v", resp.StatusCode, body)
+	}
+
+	_, mine := ts.do(t, "GET", "/api/v1/notes?q=hemmeligt", nil)
+	if got := len(mine["notes"].([]any)); got != 1 {
+		t.Fatalf("the author found %d of their own notes", got)
+	}
+
+	other := ts.newUser(t, "[email protected]", "Anden")
+	_, theirs := other.do(t, "GET", "/api/v1/notes?q=hemmeligt", nil)
+	if got := len(theirs["notes"].([]any)); got != 0 {
+		t.Errorf("a stranger's search returned %d notes", got)
+	}
+}
+
+// The backwards question, which is what makes notes worth linking at all.
+func TestANoteIsFoundFromTheTaskItMentions(t *testing.T) {
+	ts := newTestServer(t)
+	ts.bootstrap(t)
+
+	_, task := ts.do(t, "POST", "/api/v1/tasks/quick-add", map[string]any{
+		"text": "ring til Anders",
+	})
+	taskID, _ := task["id"].(string)
+	if taskID == "" {
+		t.Fatalf("no task id: %v", task)
+	}
+
+	if resp, _ := ts.do(t, "POST", "/api/v1/notes", map[string]any{
+		"body": "Aftalt at han ringer først, se /opgave/" + taskID,
+	}); resp.StatusCode != http.StatusCreated {
+		t.Fatal("the note was not written")
+	}
+
+	_, found := ts.do(t, "GET", "/api/v1/notes/linking/task/"+taskID, nil)
+	notes, _ := found["notes"].([]any)
+	if len(notes) != 1 {
+		t.Fatalf("%d notes point at the task, want 1", len(notes))
+	}
+}
+
+// Editing the text moves the links with it. A link that outlives its mention
+// claims a connection that is not there.
+func TestChangingANoteChangesWhatItPointsAt(t *testing.T) {
+	ts := newTestServer(t)
+	ts.bootstrap(t)
+
+	_, note := ts.do(t, "POST", "/api/v1/notes", map[string]any{"body": "Om #Firma"})
+	id, _ := note["id"].(string)
+
+	_, before := ts.do(t, "GET", "/api/v1/notes/linking/project/Firma", nil)
+	if len(before["notes"].([]any)) != 1 {
+		t.Fatal("the first save recorded nothing")
+	}
+
+	if resp, _ := ts.do(t, "PATCH", "/api/v1/notes/"+id, map[string]any{
+		"body": "Om #Regnskab i stedet",
+	}); resp.StatusCode != http.StatusOK {
+		t.Fatal("the note was not changed")
+	}
+
+	_, after := ts.do(t, "GET", "/api/v1/notes/linking/project/Firma", nil)
+	if got := len(after["notes"].([]any)); got != 0 {
+		t.Errorf("%d notes still point at Firma", got)
+	}
+}
+
+// The export is the promise the whole design was arranged around: the note on
+// disk is already the file you would export, so nothing is converted on the way
+// out and nothing can be lost in the conversion.
+func TestNotesExportAsMarkdownFiles(t *testing.T) {
+	ts := newTestServer(t)
+	ts.bootstrap(t)
+
+	bodies := []string{
+		"# Møde med Anders\n\nHan vil gerne have **kaffe** hver uge.",
+		"Slash/i/titlen\n\nog noget tekst",
+		"# Møde med Anders\n\nen anden note med samme titel",
+	}
+	for _, body := range bodies {
+		if resp, _ := ts.do(t, "POST", "/api/v1/notes", map[string]any{"body": body}); resp.StatusCode != http.StatusCreated {
+			t.Fatalf("create: %d", resp.StatusCode)
+		}
+	}
+
+	req, _ := http.NewRequest("GET", ts.URL+"/api/v1/export/notes.zip", nil)
+	req.Header.Set("Sec-Fetch-Site", "same-origin")
+	for _, c := range ts.client.Jar.Cookies(mustParse(t, ts.URL)) {
+		req.AddCookie(c)
+	}
+	resp, err := ts.client.Do(req)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != http.StatusOK {
+		t.Fatalf("export: status %d", resp.StatusCode)
+	}
+	if ct := resp.Header.Get("Content-Type"); ct != "application/zip" {
+		t.Errorf("content type is %q", ct)
+	}
+
+	raw, err := io.ReadAll(resp.Body)
+	if err != nil {
+		t.Fatal(err)
+	}
+	zr, err := zip.NewReader(bytes.NewReader(raw), int64(len(raw)))
+	if err != nil {
+		t.Fatalf("the archive does not open: %v", err)
+	}
+	if len(zr.File) != 3 {
+		t.Fatalf("the archive holds %d files, want 3", len(zr.File))
+	}
+
+	byName := map[string]string{}
+	for _, f := range zr.File {
+		r, err := f.Open()
+		if err != nil {
+			t.Fatal(err)
+		}
+		text, _ := io.ReadAll(r)
+		r.Close()
+		byName[f.Name] = string(text)
+	}
+
+	// Exactly what was stored, byte for byte. A converted export is an export that
+	// can be wrong.
+	if got := byName["Møde med Anders.md"]; got != bodies[0] {
+		t.Errorf("the note came out as %q", got)
+	}
+	// A slash in a title would make a directory, and on Windows it is refused
+	// outright.
+	if _, ok := byName["Slash-i-titlen.md"]; !ok {
+		t.Errorf("the awkward title became %v", keysOf(byName))
+	}
+	// Two notes with the same title are two notes; one entry twice is one lost.
+	if _, ok := byName["Møde med Anders (2).md"]; !ok {
+		t.Errorf("the second note of the same name is missing: %v", keysOf(byName))
+	}
+}
+
+func keysOf(m map[string]string) []string {
+	out := make([]string, 0, len(m))
+	for k := range m {
+		out = append(out, k)
+	}
+	return out
+}
+
+// Out and back in again. If an export cannot be imported, it is not an export —
+// it is a file somebody hopes will be readable later.
+func TestNotesSurviveTheRoundTripThroughAZip(t *testing.T) {
+	ts := newTestServer(t)
+	ts.bootstrap(t)
+
+	var archive bytes.Buffer
+	zw := zip.NewWriter(&archive)
+	files := map[string]string{
+		"Møde med Anders.md": "# Møde med Anders\n\nHan vil have **kaffe** hver uge. #Firma",
+		"noget andet.md":     "Løse tanker\n\nog en linje til",
+		// A zip made on a Mac carries these beside every file. Importing them would
+		// double the whole library, with each copy full of binary rubbish.
+		"__MACOSX/._Møde med Anders.md": "\x00\x05\x16\x07binært",
+		"billede.png":                   "ikke en note",
+		"tom.md":                        "   \n  ",
+	}
+	for name, body := range files {
+		f, err := zw.Create(name)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if _, err := io.WriteString(f, body); err != nil {
+			t.Fatal(err)
+		}
+	}
+	if err := zw.Close(); err != nil {
+		t.Fatal(err)
+	}
+
+	var form bytes.Buffer
+	mw := multipart.NewWriter(&form)
+	part, _ := mw.CreateFormFile("file", "noter.zip")
+	part.Write(archive.Bytes())
+	mw.Close()
+
+	req, _ := http.NewRequest("POST", ts.URL+"/api/v1/notes/import", &form)
+	req.Header.Set("Content-Type", mw.FormDataContentType())
+	req.Header.Set("Sec-Fetch-Site", "same-origin")
+	for _, c := range ts.client.Jar.Cookies(mustParse(t, ts.URL)) {
+		req.AddCookie(c)
+	}
+	resp, err := ts.client.Do(req)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != http.StatusOK {
+		t.Fatalf("import: status %d", resp.StatusCode)
+	}
+
+	var out struct{ Created, Skipped int }
+	json.NewDecoder(resp.Body).Decode(&out)
+	if out.Created != 2 {
+		t.Fatalf("imported %d notes, want the 2 real ones", out.Created)
+	}
+
+	// The title came from the first line, not from the filename — which is the same
+	// rule as everywhere else, and the reason renaming a file cannot rename a note.
+	_, listed := ts.do(t, "GET", "/api/v1/notes", nil)
+	titles := map[string]bool{}
+	for _, raw := range listed["notes"].([]any) {
+		titles[raw.(map[string]any)["title"].(string)] = true
+	}
+	if !titles["Møde med Anders"] || !titles["Løse tanker"] {
+		t.Errorf("the titles came out as %v", titles)
+	}
+
+	// And the #tag was read on the way in, so an imported note lands on its project
+	// exactly as a typed one does.
+	_, linked := ts.do(t, "GET", "/api/v1/notes/linking/project/Firma", nil)
+	if len(linked["notes"].([]any)) != 1 {
+		t.Errorf("the imported note did not link to its project")
+	}
+}
+
+// A note from Apple Notes is full of photographs. One that arrives as words alone
+// is not that note — it is a summary of it.
+func TestAnImportedNoteKeepsItsPictures(t *testing.T) {
+	ts := newTestServer(t)
+	ts.bootstrap(t)
+
+	var archive bytes.Buffer
+	zw := zip.NewWriter(&archive)
+	write := func(name, body string) {
+		f, err := zw.Create(name)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if _, err := io.WriteString(f, body); err != nil {
+			t.Fatal(err)
+		}
+	}
+	write("noter/Kvittering.md", "# Kvittering\n\nHer er den:\n\n![](vedhaeftninger/bon.png)\n\nog resten af teksten")
+	write("noter/vedhaeftninger/bon.png", "\x89PNG\r\n\x1a\nlad som om")
+	// Another note in the same archive, which must not inherit the first one's
+	// picture: an archive is one folder for many notes.
+	write("noter/Uden billede.md", "Uden billede\n\nbare tekst")
+	if err := zw.Close(); err != nil {
+		t.Fatal(err)
+	}
+
+	var form bytes.Buffer
+	mw := multipart.NewWriter(&form)
+	part, _ := mw.CreateFormFile("file", "noter.zip")
+	part.Write(archive.Bytes())
+	mw.Close()
+
+	req, _ := http.NewRequest("POST", ts.URL+"/api/v1/notes/import", &form)
+	req.Header.Set("Content-Type", mw.FormDataContentType())
+	req.Header.Set("Sec-Fetch-Site", "same-origin")
+	for _, c := range ts.client.Jar.Cookies(mustParse(t, ts.URL)) {
+		req.AddCookie(c)
+	}
+	resp, err := ts.client.Do(req)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer resp.Body.Close()
+
+	var out struct{ Created, Skipped, Files int }
+	json.NewDecoder(resp.Body).Decode(&out)
+	if out.Created != 2 || out.Files != 1 {
+		t.Fatalf("imported %d notes and %d files, want 2 and 1", out.Created, out.Files)
+	}
+
+	// The list carries a preview, not the whole note — see briefly(). The body is
+	// fetched by id, which is what the interface does when it opens one.
+	_, listed := ts.do(t, "GET", "/api/v1/notes?q=kvittering", nil)
+	notes := listed["notes"].([]any)
+	if len(notes) != 1 {
+		t.Fatalf("found %d notes", len(notes))
+	}
+	noteID := notes[0].(map[string]any)["id"].(string)
+	if got := notes[0].(map[string]any)["body"]; got != nil && got != "" {
+		t.Errorf("the list carried a body: %v — an editor handed that would save the truncation", got)
+	}
+	_, whole := ts.do(t, "GET", "/api/v1/notes/"+noteID, nil)
+	body := whole["body"].(string)
+
+	// The link points at the file where it now lives, not at a path inside an
+	// archive nobody kept.
+	if strings.Contains(body, "vedhaeftninger/bon.png") {
+		t.Errorf("the link still points into the archive: %q", body)
+	}
+	if !strings.Contains(body, "/api/v1/attachments/") {
+		t.Errorf("the picture was not attached: %q", body)
+	}
+	// And it is still where it was written, in the middle of the note.
+	if !strings.HasPrefix(body, "# Kvittering") || !strings.Contains(body, "og resten af teksten") {
+		t.Errorf("the note was rearranged: %q", body)
+	}
+
+	// The picture is really there and really readable.
+	id := body[strings.Index(body, "/api/v1/attachments/")+len("/api/v1/attachments/"):]
+	id = strings.SplitN(id, ")", 2)[0]
+	got, _ := ts.do(t, "GET", "/api/v1/attachments/"+id, nil)
+	if got.StatusCode != http.StatusOK {
+		t.Errorf("the attachment answers %d", got.StatusCode)
+	}
+
+	// The other note did not inherit it.
+	_, other := ts.do(t, "GET", "/api/v1/notes?q=Uden", nil)
+	for _, raw := range other["notes"].([]any) {
+		if strings.Contains(raw.(map[string]any)["body"].(string), "attachments/") {
+			t.Error("a note that mentioned no picture was given one")
+		}
+	}
+}

internal/httpapi/notifications_handlers.go

@@ -1,12 +1,16 @@
 package httpapi
 
 import (
+	"errors"
 	"net/http"
+	"net/url"
+	"strings"
 	"time"
 
 	"github.com/go-chi/chi/v5"
 
 	"github.com/kristianwind/verdande/internal/push"
+	"github.com/kristianwind/verdande/internal/safedial"
 	"github.com/kristianwind/verdande/internal/store"
 )
 
@@ -104,18 +108,44 @@ func (s *Server) PushToUser(userID, title, body, projectID string) {
 	s.pushToUser(userID, title, body, projectID)
 }
 
-func (s *Server) pushToUser(userID, title, body, projectID string) {
+// pushOutcome is what happened, per device.
+//
+// It exists because "nothing arrives" was unanswerable. A push that a service
+// refuses is the ordinary failure here — a stale subscription, a VAPID subject the
+// service will not take, a browser that revoked permission without telling the
+// server — and every one of them looked exactly like silence.
+type pushOutcome struct {
+	Subscriptions int           `json:"subscriptions"`
+	Sent          int           `json:"sent"`
+	Failed        []pushFailure `json:"failed"`
+}
+
+// pushFailure names the service and quotes what it said.
+//
+// The host and not the endpoint: the rest of that URL is the credential the push
+// service issued for this device, and it does not belong in an answer, a log line
+// or a screenshot.
+type pushFailure struct {
+	Service string `json:"service"`
+	Reason  string `json:"reason"`
+}
+
+func (s *Server) pushToUser(userID, title, body, projectID string) pushOutcome {
 	ctx, cancel := contextWithBackgroundTimeout(30 * time.Second)
 	defer cancel()
 
+	var out pushOutcome
 	subs, err := s.db.ListPushSubscriptions(ctx, userID)
 	if err != nil || len(subs) == 0 {
-		return
+		return out
 	}
+	out.Subscriptions = len(subs)
+
 	public, private, err := s.vapidKeys(ctx)
 	if err != nil {
 		s.log.Warn("vapid keys", "err", err)
-		return
+		out.Failed = append(out.Failed, pushFailure{Service: "verdande", Reason: err.Error()})
+		return out
 	}
 
 	payload := push.Payload{Title: title, Body: body, URL: "/projekt/" + projectID}
@@ -126,13 +156,101 @@ func (s *Server) pushToUser(userID, title, body, projectID string) {
 			Public: public, Private: private, Subject: "mailto:" + s.cfg.SMTP.From,
 		})
 		if err == nil {
+			out.Sent++
 			continue
 		}
-		s.log.Debug("web push failed", "err", err, "endpoint", sub.Endpoint)
+		// Warn, not Debug.
+		//
+		// This was the one line that would have said why no notification ever
+		// arrived, and at Debug it is not printed on an instance running at the
+		// default level. A delivery that fails silently and a delivery that does
+		// not happen look the same from the outside, and the difference is the
+		// whole diagnosis.
+		reason := pushReason(sub.Endpoint, err)
+		s.log.Warn("web push refused", "reason", reason, "service", pushHost(sub.Endpoint), "user", userID)
+		out.Failed = append(out.Failed, pushFailure{
+			Service: pushHost(sub.Endpoint),
+			Reason:  reason,
+		})
 		if recErr := s.db.RecordPushFailure(ctx, sub.Endpoint, push.IsGone(err)); recErr != nil {
 			s.log.Warn("record push failure", "err", recErr)
 		}
 	}
+	return out
+}
+
+// pushReason is what went wrong, with the endpoint taken back out of it.
+//
+// Go wraps a transport failure as `*url.Error`, and its message is `Post
+// "https://fcm.googleapis.com/fcm/send/dQw4w9…": dial tcp: …` — the whole
+// endpoint, which is the credential the push service issued for that device. It
+// would have gone into the answer, the log line and any screenshot of either. A
+// test written to prove the host was reported instead is what found it.
+//
+// Unwrapped first, so the cause is what is quoted. Then the endpoint is scrubbed
+// anyway: the next error type to carry it will not come with a warning.
+func pushReason(endpoint string, err error) string {
+	var urlErr *url.Error
+	if errors.As(err, &urlErr) && urlErr.Err != nil {
+		err = urlErr.Err
+	}
+	reason := err.Error()
+	if endpoint != "" {
+		reason = strings.ReplaceAll(reason, endpoint, pushHost(endpoint))
+	}
+	return reason
+}
+
+// pushHost is the service an endpoint belongs to, and nothing else from it.
+func pushHost(endpoint string) string {
+	u, err := url.Parse(endpoint)
+	if err != nil || u.Host == "" {
+		return "ukendt"
+	}
+	return u.Host
+}
+
+// handlePushTest sends one notification to this account's devices and says what
+// happened to it.
+//
+// Reported as "der kommer ikke nogen". Everything about that was invisible: the
+// settings page said "on for this device" as soon as a subscription existed, and a
+// refusal from the push service went into a Debug line nobody sees. There was no
+// way to tell "the browser never subscribed" from "the service refused it" from
+// "nothing has come due yet" — three different problems with one appearance.
+//
+// It goes through the same path as a real notification rather than a shortcut, so
+// what it proves is the thing that actually has to work.
+//
+// The words come from the client, which is where the dictionaries are. A server
+// that carries its own copy of "This is a test" carries it in one language, and
+// this one deliberately keeps its prose in the interface — see
+// `internal/i18n`. The text is only ever shown back to the person who asked for
+// it, on their own devices.
+func (s *Server) handlePushTest(w http.ResponseWriter, r *http.Request) {
+	var req struct {
+		Title string `json:"title"`
+		Body  string `json:"body"`
+	}
+	if err := decodeJSON(w, r, &req); err != nil {
+		return
+	}
+	title := strings.TrimSpace(req.Title)
+	if title == "" {
+		title = "verdande"
+	}
+	// Bounded: this is written into a notification on somebody's lock screen, and
+	// a megabyte of title is not a notification.
+	if len(title) > 200 {
+		title = title[:200]
+	}
+	body := strings.TrimSpace(req.Body)
+	if len(body) > 500 {
+		body = body[:500]
+	}
+
+	user := userFrom(r.Context())
+	writeJSON(w, http.StatusOK, s.pushToUser(user.ID, title, body, ""))
 }
 
 func (s *Server) vapidKeys(ctx contextLike) (string, string, error) {
@@ -170,6 +288,23 @@ func (s *Server) handleSubscribePush(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
+	// The endpoint is an address this server will POST to, on a schedule the
+	// caller chooses — set a reminder a minute out and the push job fetches it,
+	// again every minute. Unchecked, that is a way to make the instance reach
+	// anything it can route to, on demand.
+	//
+	// https only: a push service is on the public internet and speaks TLS. Nothing
+	// legitimate needs http here, and allowing it is the difference between a
+	// blind request and a readable one.
+	if !strings.HasPrefix(req.Endpoint, "https://") {
+		writeFieldErrors(w, map[string]string{"endpoint": "must be an https address"})
+		return
+	}
+	if reason := safedial.CheckURL(req.Endpoint); reason != "" {
+		writeFieldErrors(w, map[string]string{"endpoint": reason})
+		return
+	}
+
 	err := s.db.SavePushSubscription(r.Context(), &store.PushSubscription{
 		UserID:    userFrom(r.Context()).ID,
 		Endpoint:  req.Endpoint,
@@ -189,7 +324,10 @@ func (s *Server) handleUnsubscribePush(w http.ResponseWriter, r *http.Request) {
 	if err := decodeJSON(w, r, &req); err != nil {
 		return
 	}
-	if err := s.db.DeletePushSubscription(r.Context(), req.Endpoint); err != nil {
+	// Scoped to the caller. It was not, so anybody who learned somebody else's
+	// endpoint could unsubscribe their device — a small thing to do to somebody
+	// and no reason at all to be able to.
+	if err := s.db.DeletePushSubscription(r.Context(), userFrom(r.Context()).ID, req.Endpoint); err != nil {
 		s.internal(w, r, "delete push subscription", err)
 		return
 	}

internal/httpapi/panel_test.go

@@ -102,7 +102,7 @@ func TestTwoRunsOfOneMailboxDoNotOverlap(t *testing.T) {
 	// Stands in for a run: takes the lock, notes how many are inside, and holds it
 	// until told to let go.
 	run := func(done chan<- struct{}) {
-		unlock := srv.lockMailbox("box-1")
+		unlock := srv.lockSync("box-1")
 		mu.Lock()
 		inside++
 		if inside > most {
@@ -136,10 +136,10 @@ func TestTwoRunsOfOneMailboxDoNotOverlap(t *testing.T) {
 
 	// And two different mailboxes must not wait for each other: one slow host is
 	// not everybody's problem.
-	a := srv.lockMailbox("box-a")
+	a := srv.lockSync("box-a")
 	done := make(chan struct{})
 	go func() {
-		srv.lockMailbox("box-b")()
+		srv.lockSync("box-b")()
 		close(done)
 	}()
 	select {

internal/httpapi/projects_handlers.go

@@ -356,6 +356,34 @@ func (s *Server) handleCreateSection(w http.ResponseWriter, r *http.Request) {
 	writeJSON(w, http.StatusCreated, sectionJSON{sec.ID, sec.ProjectID, sec.Name, sec.SortOrder})
 }
 
+// handleReorderSections sets the order of the sections inside one project.
+//
+// Under /projects/{projectID}/ rather than beside the other section routes, which
+// hang off a section id: the thing being changed here is the project's list, not
+// any one section in it. That also puts it behind the same project permission
+// check as everything else in this subtree, instead of resolving a section to its
+// project one id at a time and hoping they all named the same one.
+func (s *Server) handleReorderSections(w http.ResponseWriter, r *http.Request) {
+	var req reorderProjectsRequest
+	if err := decodeJSON(w, r, &req); err != nil {
+		return
+	}
+	// The same ceiling as the projects list, and a bound on the transaction rather
+	// than an opinion about how many sections a project may have.
+	if len(req.IDs) > 500 {
+		writeFieldErrors(w, map[string]string{"ids": "at most 500 at a time"})
+		return
+	}
+
+	projectID := chi.URLParam(r, "projectID")
+	if err := s.db.ReorderSections(r.Context(), projectID, req.IDs); err != nil {
+		s.internal(w, r, "reorder sections", err)
+		return
+	}
+	s.activity(r, projectID, "", "section.updated", nil)
+	w.WriteHeader(http.StatusNoContent)
+}
+
 // sectionAccess resolves a section to its project and checks the caller may edit
 // it. Sections have no permissions of their own — they belong to a project, and
 // that is where access is decided.

internal/httpapi/projects_test.go

@@ -327,6 +327,71 @@ func TestAProjectCanHaveSeveralSections(t *testing.T) {
 	}
 }
 
+// Sections can be dragged into another order, and the order is the project's.
+//
+// The list is what a project's plan *is* — "Planlægning" before "I gang" is the
+// order the work happens in — and until this endpoint existed the only way to
+// change it was to delete a section and make it again, which moves its tasks to
+// the unsectioned area on the way past.
+func TestSectionsCanBeReordered(t *testing.T) {
+	ts := newTestServer(t)
+	ts.bootstrap(t)
+
+	_, project := ts.do(t, "POST", "/api/v1/projects", map[string]any{"name": "Ombygning"})
+	id := project["id"].(string)
+
+	ids := map[string]string{}
+	names := []string{"Planlægning", "I gang", "Til gennemsyn"}
+	for _, name := range names {
+		_, body := ts.do(t, "POST", "/api/v1/projects/"+id+"/sections", map[string]any{"name": name})
+		ids[name] = body["id"].(string)
+	}
+
+	want := []string{"Til gennemsyn", "Planlægning", "I gang"}
+	order := make([]string, len(want))
+	for i, name := range want {
+		order[i] = ids[name]
+	}
+
+	resp, body := ts.do(t, "POST", "/api/v1/projects/"+id+"/sections/reorder",
+		map[string]any{"ids": order})
+	if resp.StatusCode != http.StatusNoContent {
+		t.Fatalf("reorder: status %d, body %v", resp.StatusCode, body)
+	}
+
+	_, listed := ts.do(t, "GET", "/api/v1/projects/"+id+"/sections", nil)
+	got, _ := listed["sections"].([]any)
+	if len(got) != len(want) {
+		t.Fatalf("the project has %d sections, want %d", len(got), len(want))
+	}
+	for i, raw := range got {
+		if name := raw.(map[string]any)["name"]; name != want[i] {
+			t.Errorf("section %d is %v, want %q", i, name, want[i])
+		}
+	}
+
+	// A section belonging to somebody else's project is not moved by naming it
+	// here. The ids in the body are not checked one by one — the WHERE clause is
+	// what refuses them — so this is the assertion that it actually does.
+	_, other := ts.do(t, "POST", "/api/v1/projects", map[string]any{"name": "Sommerhus"})
+	otherID := other["id"].(string)
+	_, foreign := ts.do(t, "POST", "/api/v1/projects/"+otherID+"/sections",
+		map[string]any{"name": "Havearbejde"})
+	foreignID := foreign["id"].(string)
+
+	resp, _ = ts.do(t, "POST", "/api/v1/projects/"+id+"/sections/reorder",
+		map[string]any{"ids": []string{foreignID}})
+	if resp.StatusCode != http.StatusNoContent {
+		t.Fatalf("reorder with a foreign id: status %d", resp.StatusCode)
+	}
+
+	_, stillThere := ts.do(t, "GET", "/api/v1/projects/"+otherID+"/sections", nil)
+	elsewhere, _ := stillThere["sections"].([]any)
+	if len(elsewhere) != 1 || elsewhere[0].(map[string]any)["name"] != "Havearbejde" {
+		t.Errorf("the other project's section did not survive: %v", elsewhere)
+	}
+}
+
 // A project can be created straight into a group.
 //
 // `group_id` was declared on the request type, documented on it, and applied by

internal/httpapi/server.go

@@ -63,7 +63,15 @@ type Server struct {
 	// the endpoints that check a secret are limited separately and more tightly
 	// than the rest of the API.
 	loginLimiter *limiter
+	// Sat kun af prøver; se icsClient().
+	icsFetch     *http.Client
+	mailLimiter  *limiter
 	resetLimiter *limiter
+	// Second factors are counted against the *account*, not the address. An
+	// address bucket is defeated by anybody with more than one address, which is
+	// the ordinary case — and a six-digit code is only safe while guesses are
+	// scarce, so the scarcity has to be counted against the thing being attacked.
+	totpLimiter *limiter
 
 	// Computed once from the built index.html; see csp.go.
 	csp string
@@ -80,7 +88,16 @@ func New(cfg *config.Config, db *store.DB, log *slog.Logger, web fs.FS) *Server
 		mail:         mail.New(cfg.SMTP, cfg.BaseURL, log),
 		hub:          realtime.NewHub(log),
 		loginLimiter: newLimiter(10, 15*time.Minute),
+		// Generous on purpose: the caller is the mail server, one address delivering
+		// everything, and a personal instance gets a handful of forwarded mails a
+		// day. Sixty a minute never touches real delivery and still puts a ceiling
+		// on the one public write path that has none.
+		mailLimiter:  newLimiter(60, time.Minute),
 		resetLimiter: newLimiter(5, time.Hour),
+		// Tighter than the password bucket, and for a whole hour. Somebody typing
+		// their own code gets it right on the first or second try; ten in an hour is
+		// generous for a person and hopeless for a search through a million.
+		totpLimiter: newLimiter(10, time.Hour),
 	}
 	s.csp = contentSecurityPolicy(scriptHashes(web))
 	if w, err := auth.NewWebAuthn(cfg.BaseURL, "verdande"); err == nil {
@@ -113,7 +130,15 @@ func New(cfg *config.Config, db *store.DB, log *slog.Logger, web fs.FS) *Server
 
 	// Inbound mail. Delivered by the mail server rather than by a browser, and
 	// authenticated by the token in the recipient address.
-	r.Post("/inbound/mail", s.handleInboundMail)
+	//
+	// Rate limited for the same reason the beacon is: it is reachable by anybody
+	// who can route to this instance. It is the weaker case of the two — the
+	// beacon writes a row for a stranger, this one writes nothing without a
+	// 256-bit address it has to already know — but an address is shared with mail
+	// servers and printed on a settings page, and once it is known there was no
+	// ceiling at all on what could be made with it.
+	r.Method(http.MethodPost, "/inbound/mail",
+		s.rateLimit(s.mailLimiter, http.HandlerFunc(s.handleInboundMail)))
 
 	// MCP with the token in the query string, for clients that cannot send a
 	// header. Claude's custom-connector dialog takes a URL and nothing else, so
@@ -133,6 +158,12 @@ func New(cfg *config.Config, db *store.DB, log *slog.Logger, web fs.FS) *Server
 	r.Group(func(r chi.Router) {
 		r.Use(s.requireAuth)
 		r.Get("/oauth/gmail/callback", s.handleGmailCallback)
+		// The calendar comes back on a URI of its own rather than sharing Gmail's.
+		// One callback deciding from stored state which of the two flows had
+		// returned would put the choice of *which token store to write* behind a
+		// lookup — and when that goes wrong it goes wrong by overwriting a working
+		// Gmail connection with calendar tokens.
+		r.Get("/oauth/calendar/callback", s.handleCalendarCallback)
 	})
 	r.Route("/caldav", s.caldavRoutes)
 
@@ -143,6 +174,19 @@ func New(cfg *config.Config, db *store.DB, log *slog.Logger, web fs.FS) *Server
 			writeJSON(w, http.StatusOK, map[string]string{"status": "ok"})
 		})
 
+		// The beacon's receiving end, and the number it produces. Both without a
+		// session, because the caller is a stranger's installation — that is the
+		// whole feature. Rate limited like the login routes: it is the one endpoint
+		// anybody on the internet can write to, and a row per request is a row per
+		// request whether or not the request is honest.
+		//
+		// Refused with a 404 unless this instance has been told it is the collector,
+		// so an ordinary installation is not a spam sink that answers 200 to
+		// anything.
+		r.Method(http.MethodPost, "/beacon",
+			s.rateLimit(s.loginLimiter, http.HandlerFunc(s.handleBeaconPing)))
+		r.Get("/beacon/count", s.handleBeaconCount)
+
 		// Reachable without being signed in — these are how you become signed in.
 		r.Route("/auth", func(r chi.Router) {
 			r.Get("/setup", s.handleSetupState)
@@ -178,13 +222,10 @@ func New(cfg *config.Config, db *store.DB, log *slog.Logger, web fs.FS) *Server
 				r.Get("/me", s.handleMe)
 				r.Patch("/me", s.handleUpdateProfile)
 				r.Put("/sidebar-sections", s.handleSetSidebarSections)
+				r.Put("/nav-order", s.handleSetNavOrder)
 				r.Post("/logout", s.handleLogout)
 				r.Post("/password/change", s.handleChangePassword)
-				r.Post("/totp/setup", s.handleTOTPSetup)
-				r.Post("/totp/confirm", s.handleTOTPConfirm)
-				r.Post("/totp/disable", s.handleTOTPDisable)
 				r.Get("/recovery-codes", s.handleRecoveryCodesCount)
-				r.Post("/recovery-codes", s.handleRecoveryCodesRegenerate)
 
 				// Behind requireSession, like the API tokens and for the same
 				// reason: a leaked token must not be able to end the sessions of
@@ -194,6 +235,23 @@ func New(cfg *config.Config, db *store.DB, log *slog.Logger, web fs.FS) *Server
 					r.Get("/sessions", s.handleListSessions)
 					r.Delete("/sessions/{sessionID}", s.handleDeleteSession)
 
+					// Turning the second factor on, and the codes that get you back
+					// in. Sessions only, and setup asks for the password.
+					//
+					// These sat outside this group, which meant the door opened with
+					// a token and closed only with a password: `disable` has always
+					// asked for the password, `setup` asked for nothing. A stolen
+					// token could therefore fetch the secret, load it into its own
+					// authenticator, confirm it, and keep the only copy of the
+					// recovery codes. The owner's next login would stop at a code
+					// they do not have, and they could not turn it off without
+					// logging in first. A theft becomes a tenancy — the same
+					// sentence written next door about passkeys, and the same rule.
+					r.Post("/totp/setup", s.handleTOTPSetup)
+					r.Post("/totp/confirm", s.handleTOTPConfirm)
+					r.Post("/totp/disable", s.handleTOTPDisable)
+					r.Post("/recovery-codes", s.handleRecoveryCodesRegenerate)
+
 					// Registering a key, and the list of them. Sessions only, for
 					// the same reason: a leaked token must not be able to add its
 					// own way in — that would turn a theft into a tenancy.
@@ -239,6 +297,9 @@ func New(cfg *config.Config, db *store.DB, log *slog.Logger, web fs.FS) *Server
 				r.Get("/key", s.handlePushKey)
 				r.Post("/subscribe", s.handleSubscribePush)
 				r.Post("/unsubscribe", s.handleUnsubscribePush)
+				// One notification, to this account's own devices, reporting what
+				// each of them did with it. The answer to "der kommer ikke nogen".
+				r.Post("/test", s.handlePushTest)
 			})
 
 			r.Route("/attachments/{attachmentID}", func(r chi.Router) {
@@ -276,6 +337,26 @@ func New(cfg *config.Config, db *store.DB, log *slog.Logger, web fs.FS) *Server
 			// Mailboxes read over IMAP — iCloud, Fastmail, any ordinary host. Each
 			// belongs to the person who connected it, so there is no admin gate
 			// here and no shared registration: the credential is theirs.
+			// Notes. Listing and searching are the same endpoint because they answer
+			// the same question with different words; the backwards one — what has
+			// been written about this task — hangs off the thing being asked about.
+			r.Route("/notes", func(r chi.Router) {
+				r.Get("/", s.handleListNotes)
+				r.Post("/", s.handleCreateNote)
+				r.Post("/import", s.handleImportNotes)
+				r.Get("/linking/{kind}/{targetID}", s.handleNotesLinking)
+				r.Get("/{noteID}", s.handleGetNote)
+				r.Patch("/{noteID}", s.handleUpdateNote)
+				r.Delete("/{noteID}", s.handleDeleteNote)
+				// A picture pasted or dropped into a note. The import could bring
+				// files in and nothing else could, which made the most ordinary act
+				// in a notes app — paste a screenshot — do nothing at all.
+				r.Post("/{noteID}/attachments", s.handleUploadNoteAttachment)
+				// Mange på én gang. Efter en import af tolv hundrede noter er det at
+				// vælge halvtreds det almindelige tilfælde, ikke det yderste.
+				r.Post("/bulk", s.handleNoteBulk)
+			})
+
 			r.Route("/mailboxes", func(r chi.Router) {
 				r.Get("/", s.handleListMailboxes)
 				r.Post("/", s.handleAddMailbox)
@@ -302,12 +383,32 @@ func New(cfg *config.Config, db *store.DB, log *slog.Logger, web fs.FS) *Server
 				})
 			})
 
+			// A calendar read from somewhere else, laid under verdande's own dated
+			// tasks. Read-only, so there is no write here to gate: the events are a
+			// copy of somebody else's calendar, and the only thing a person decides
+			// is which of them to look at.
+			r.Route("/calendar", func(r chi.Router) {
+				r.Get("/", s.handleGetCalendar)
+				r.Put("/calendars", s.handleSetCalendars)
+				r.Delete("/", s.handleDisconnectCalendar)
+				r.Post("/authorize", s.handleCalendarAuthorize)
+				r.Post("/sync", s.handleCalendarSyncNow)
+				r.Get("/events", s.handleCalendarEvents)
+
+				// Abonnementer: en kalender, man kun har en adresse til. Flere pr.
+				// person, hvor Google er én — det er adressen, der er identiteten,
+				// hvor tokenet er det for OAuth.
+				r.Post("/subscriptions", s.handleSubscribeCalendar)
+				r.Delete("/subscriptions/{id}", s.handleUnsubscribeCalendar)
+			})
+
 			r.Route("/import", func(r chi.Router) {
 				r.Post("/todoist", s.handleImportTodoist)
 				r.Post("/csv", s.handleImportCSV)
 			})
 
 			r.Get("/export/account", s.handleExportAccount)
+			r.Get("/export/notes.zip", s.handleExportNotes)
 			r.Get("/export/projects/{projectID}.csv", s.handleExportProject)
 			r.Get("/export/projects/{projectID}.ics", s.handleExportProjectICS)
 
@@ -350,6 +451,7 @@ func New(cfg *config.Config, db *store.DB, log *slog.Logger, web fs.FS) *Server
 					r.Group(func(r chi.Router) {
 						r.Use(s.requireProject(store.RoleEditor))
 						r.Post("/sections", s.handleCreateSection)
+						r.Post("/sections/reorder", s.handleReorderSections)
 					})
 
 					r.Group(func(r chi.Router) {
@@ -375,6 +477,11 @@ func New(cfg *config.Config, db *store.DB, log *slog.Logger, web fs.FS) *Server
 				// `:latest` on the way, which is what makes a restart an update.
 				r.Get("/panel", s.handlePanelStatus)
 				r.Post("/panel/restart", s.handleRestartFromPanel)
+				// Who this instance reports to, and whether it does. An
+				// administrator's decision, not a person's: there is one
+				// installation and it either phones home or it does not.
+				r.Get("/beacon/settings", s.handleBeaconStatus)
+				r.Put("/beacon/settings", s.handleSetBeacon)
 				// A backup file is a complete copy of the database, so this whole
 				// group is sessions-only as well as administrators-only: a leaked
 				// token must not be able to download everybody's data.

internal/httpapi/tasks_test.go

@@ -6,6 +6,7 @@ import (
 	"io"
 	"mime/multipart"
 	"net/http"
+	"net/url"
 	"strings"
 	"testing"
 	"time"
@@ -1777,3 +1778,42 @@ func TestQuickAddSectionIDIsCheckedAgainstTheProject(t *testing.T) {
 		t.Errorf("content = %v", moved["content"])
 	}
 }
+
+// A word inside a word, on the task side.
+//
+// The notes search grew this first — a note holding `keepInventory` could not be
+// found by typing "keep inventory" — and a task is the same sentence with a
+// different table behind it. `SpeedAdmin` is one token, so "speed admin" asks for
+// two words that are nowhere.
+//
+// Having it in one of the two searches would be worse than having it in neither:
+// "it finds it in my notes but not in my tasks" is the next report.
+func TestATaskIsFoundByAWordInsideAWord(t *testing.T) {
+	ts := newTestServer(t)
+	ts.bootstrap(t)
+
+	ts.do(t, "POST", "/api/v1/tasks", map[string]any{
+		"content": "Opret kodeord til Kulturskolen (SpeedAdmin)",
+	})
+	ts.do(t, "POST", "/api/v1/tasks", map[string]any{"content": "Køb kaffe"})
+
+	for _, tc := range []struct {
+		query string
+		want  int
+	}{
+		{"speed admin", 1},
+		{"admin", 1},
+		{"speedadmin", 1},
+		{"kulturskolen", 1},
+		{"vandhane", 0},
+	} {
+		resp, body := ts.do(t, "GET", "/api/v1/search?q="+url.QueryEscape(tc.query), nil)
+		if resp.StatusCode != http.StatusOK {
+			t.Fatalf("%q: status %d", tc.query, resp.StatusCode)
+		}
+		tasks, _ := body["tasks"].([]any)
+		if len(tasks) != tc.want {
+			t.Errorf("%q found %d tasks, want %d", tc.query, len(tasks), tc.want)
+		}
+	}
+}

internal/httpapi/totp_handlers.go

@@ -20,7 +20,24 @@ type totpSetupResponse struct {
 }
 
 func (s *Server) handleTOTPSetup(w http.ResponseWriter, r *http.Request) {
+	// The password, the same as disable has always asked for.
+	//
+	// Symmetry is the point. Turning the second factor on is at least as
+	// consequential as turning it off — it decides which device gets to say yes
+	// from now on — and a door that opens more easily than it closes is not a
+	// door. Together with the move behind requireSession, this is what stops a
+	// stolen credential from enrolling its own authenticator and keeping the only
+	// copy of the recovery codes.
+	var req totpDisableRequest
+	if err := decodeJSON(w, r, &req); err != nil {
+		return
+	}
 	user := userFrom(r.Context())
+	if err := auth.VerifyPassword(user.PasswordHash, req.Password); err != nil {
+		writeFieldErrors(w, map[string]string{"password": "not correct"})
+		return
+	}
+
 	if user.TOTPEnabled {
 		writeError(w, http.StatusConflict, CodeConflict,
 			"two-factor authentication is already switched on")

internal/ics/ics.go

@@ -367,3 +367,180 @@ func unescape(s string) string {
 	r := strings.NewReplacer(`\n`, "\n", `\N`, "\n", `\,`, ",", `\;`, ";", `\\`, `\`)
 	return r.Replace(s)
 }
+
+// --- reading a whole calendar ------------------------------------------------------
+
+// Event is one VEVENT, reduced to what a grid needs — the same shape the Google
+// side already stores, so the two arrive in the database identically.
+//
+// Days at both ends, inclusive, because that is the question a grid asks: which
+// cells does this cover. StartsAt keeps the stamp as the file wrote it, offset and
+// all: it is what the chip shows, and reparsing it here would ask *this process*
+// what time zone it is in.
+type Event struct {
+	UID      string
+	Summary  string
+	Location string
+	URL      string
+	AllDay   bool
+	StartsAt string // RFC3339, empty for an all-day event
+	EndsAt   string
+	StartDay string // YYYY-MM-DD
+	EndDay   string
+}
+
+// Subscribed is what an .ics file somebody subscribed to says.
+//
+// Its own name rather than `Calendar`: that one is the *writing* side — what
+// verdande publishes as a feed — and the two are different documents that happen
+// to share a format. One name for both would be a promise that a round trip
+// through this package is lossless, which it is not and does not need to be.
+type Subscribed struct {
+	Name     string
+	TimeZone string
+	Events   []Event
+}
+
+// ParseCalendar reads an .ics file that somebody subscribed to.
+//
+// Forgiving in the same way ParseVTODO is, and for a sharper reason: this file was
+// written by somebody else's software and is fetched on a schedule with nobody
+// watching. One property this does not understand must not cost the other four
+// hundred events in the file — so anything unrecognised is skipped, and an event
+// without the two things a grid cannot do without (a uid and a start) is dropped
+// rather than stored half-made.
+//
+// # What it deliberately does not do
+//
+// **Recurrence is not expanded.** RRULE in a subscribed calendar means "and then
+// every Tuesday until 2031", and expanding it here would mean writing a year of
+// rows per rule and re-deciding what happens when the file changes. A recurring
+// event is stored as its first occurrence, which is honest — it is what the file
+// says on its own terms — and the day it matters, the answer is an expander shared
+// with `internal/recurrence`, not a second one written here.
+//
+// **Time zones are not resolved.** A DTSTART with TZID=Europe/Copenhagen is stored
+// with the offset the file carries or, when it carries none, as a local stamp. The
+// alternative is shipping a tz database and deciding what to do when the file
+// names a zone this build has never heard of. The day that matters, it is one
+// place.
+func ParseCalendar(body string) Subscribed {
+	var cal Subscribed
+	var current *Event
+	depth := 0
+
+	for _, line := range unfold(body) {
+		name, params, value := splitLine(line)
+		upper := strings.ToUpper(name)
+
+		switch upper {
+		case "BEGIN":
+			if strings.EqualFold(value, "VEVENT") {
+				current = &Event{}
+			}
+			depth++
+			continue
+		case "END":
+			depth--
+			if strings.EqualFold(value, "VEVENT") && current != nil {
+				if current.UID != "" && current.StartDay != "" {
+					cal.Events = append(cal.Events, *current)
+				}
+				current = nil
+			}
+			continue
+		}
+
+		if current == nil {
+			// Calendar-level properties. X-WR-CALNAME is what every publisher uses
+			// to say what the calendar is called; there is no standard property for
+			// it, which is why a non-standard one is read here.
+			switch upper {
+			case "X-WR-CALNAME":
+				cal.Name = unescape(value)
+			case "X-WR-TIMEZONE":
+				cal.TimeZone = value
+			}
+			continue
+		}
+
+		switch upper {
+		case "UID":
+			current.UID = value
+		case "SUMMARY":
+			current.Summary = unescape(value)
+		case "LOCATION":
+			current.Location = unescape(value)
+		case "URL":
+			current.URL = value
+		case "DTSTART":
+			current.AllDay = isDateOnly(params, value)
+			current.StartDay, current.StartsAt = readStamp(params, value)
+		case "DTEND":
+			day, at := readStamp(params, value)
+			current.EndsAt = at
+			// DTEND is exclusive for an all-day event: a one-day event ends on the
+			// next morning. Stored inclusive, or every all-day event would cover one
+			// cell too many — and a public holiday would eat the day after it.
+			if current.AllDay {
+				day = shiftDay(day, -1)
+			}
+			current.EndDay = day
+		}
+	}
+
+	// A missing DTEND means the event ends when it starts. Filled after the loop
+	// rather than inside it, because DTEND may arrive before DTSTART in a file
+	// nobody promised would be in order.
+	for i := range cal.Events {
+		if cal.Events[i].EndDay == "" || cal.Events[i].EndDay < cal.Events[i].StartDay {
+			cal.Events[i].EndDay = cal.Events[i].StartDay
+		}
+	}
+	return cal
+}
+
+// isDateOnly reports whether a stamp is a day rather than a moment. VALUE=DATE
+// says so outright; an eight-character value says it by being one.
+func isDateOnly(params, value string) bool {
+	if strings.Contains(strings.ToUpper(params), "VALUE=DATE") {
+		return true
+	}
+	return len(value) == 8 && !strings.ContainsAny(value, "T")
+}
+
+// readStamp returns the day and, for a timed event, the moment as RFC3339.
+//
+// Three shapes exist in the wild: 20260821 (a day), 20260821T140000Z (UTC), and
+// 20260821T140000 with a TZID parameter (a local time in a named zone). The third
+// is kept as written, without a zone: resolving it needs a tz database, and a
+// stamp that says 14:00 is closer to the truth than one this process has moved.
+func readStamp(params, value string) (day, at string) {
+	value = strings.TrimSpace(value)
+	if len(value) < 8 {
+		return "", ""
+	}
+	day = value[0:4] + "-" + value[4:6] + "-" + value[6:8]
+	if len(value) < 15 || value[8] != 'T' {
+		return day, ""
+	}
+
+	clock := value[9:11] + ":" + value[11:13] + ":" + value[13:15]
+	switch {
+	case strings.HasSuffix(value, "Z"):
+		return day, day + "T" + clock + "Z"
+	default:
+		// A local stamp, with or without a TZID. Written without an offset, which
+		// is what the interface already treats as "the clock the file said".
+		return day, day + "T" + clock
+	}
+}
+
+// shiftDay moves a YYYY-MM-DD by whole days.
+func shiftDay(day string, by int) string {
+	t, err := time.Parse("2006-01-02", day)
+	if err != nil {
+		return day
+	}
+	return t.AddDate(0, 0, by).Format("2006-01-02")
+}

internal/ics/ics_test.go

@@ -220,3 +220,101 @@ func TestFilename(t *testing.T) {
 		}
 	}
 }
+
+// En abonnementskalender, som den ser ud fra nogen andens software.
+//
+// Alle fire former, der findes i naturen, i én fil: en heldagsbegivenhed, en med
+// et UTC-stempel, en med TZID og lokal tid, og en over flere dage. Plus en, der
+// mangler det, et gitter ikke kan undvære, og en foldet linje — begge dele
+// kommer, og de kommer uden varsel.
+func TestParseCalendarReadsTheFourShapesThatExist(t *testing.T) {
+	body := "BEGIN:VCALENDAR\r\n" +
+		"VERSION:2.0\r\n" +
+		"X-WR-CALNAME:Helligdage\r\n" +
+		"BEGIN:VEVENT\r\n" +
+		"UID:[email protected]\r\n" +
+		"DTSTART;VALUE=DATE:20260824\r\n" +
+		"DTEND;VALUE=DATE:20260825\r\n" +
+		"SUMMARY:Grundlovsdag\r\n" +
+		"END:VEVENT\r\n" +
+		"BEGIN:VEVENT\r\n" +
+		"UID:[email protected]\r\n" +
+		"DTSTART:20260825T120000Z\r\n" +
+		"DTEND:20260825T133000Z\r\n" +
+		`SUMMARY:Møde med en meget lang titel\, der er foldet over to lin` + "\r\n" + " jer\r\n" +
+		"END:VEVENT\r\n" +
+		"BEGIN:VEVENT\r\n" +
+		"UID:[email protected]\r\n" +
+		"DTSTART;TZID=Europe/Copenhagen:20260826T090000\r\n" +
+		"DTEND;TZID=Europe/Copenhagen:20260826T100000\r\n" +
+		"SUMMARY:Tandlæge\r\n" +
+		"END:VEVENT\r\n" +
+		"BEGIN:VEVENT\r\n" +
+		"UID:[email protected]\r\n" +
+		"DTSTART;VALUE=DATE:20260901\r\n" +
+		"DTEND;VALUE=DATE:20260904\r\n" +
+		"SUMMARY:Ferie\r\n" +
+		"END:VEVENT\r\n" +
+		"BEGIN:VEVENT\r\n" +
+		"SUMMARY:Uden uid og uden start\r\n" +
+		"END:VEVENT\r\n" +
+		"END:VCALENDAR\r\n"
+
+	cal := ParseCalendar(body)
+
+	if cal.Name != "Helligdage" {
+		t.Errorf("kalenderens navn = %q", cal.Name)
+	}
+	if len(cal.Events) != 4 {
+		t.Fatalf("%d begivenheder, want 4 — den femte mangler både uid og start", len(cal.Events))
+	}
+
+	// Heldag. DTEND er eksklusiv i filen: en endagsbegivenhed slutter næste morgen.
+	// Gemmes inklusivt, ellers dækker hver eneste heldagsbegivenhed én celle for
+	// meget — og en helligdag æder dagen efter sig.
+	one := cal.Events[0]
+	if !one.AllDay || one.StartDay != "2026-08-24" || one.EndDay != "2026-08-24" {
+		t.Errorf("heldag: %+v", one)
+	}
+	if one.StartsAt != "" {
+		t.Errorf("en heldagsbegivenhed fik et klokkeslæt: %q", one.StartsAt)
+	}
+
+	// UTC, og den foldede linje samlet igen.
+	two := cal.Events[1]
+	if two.StartsAt != "2026-08-25T12:00:00Z" || two.EndsAt != "2026-08-25T13:30:00Z" {
+		t.Errorf("utc: %+v", two)
+	}
+	if two.Summary != "Møde med en meget lang titel, der er foldet over to linjer" {
+		t.Errorf("den foldede linje blev ikke samlet: %q", two.Summary)
+	}
+
+	// Lokal tid med TZID: klokkeslættet står, som filen skrev det. At flytte det
+	// her ville spørge *denne* proces, hvilken tidszone den er i.
+	three := cal.Events[2]
+	if three.StartsAt != "2026-08-26T09:00:00" {
+		t.Errorf("lokal: %q", three.StartsAt)
+	}
+
+	// Flere dage, begge ender inklusive.
+	four := cal.Events[3]
+	if four.StartDay != "2026-09-01" || four.EndDay != "2026-09-03" {
+		t.Errorf("ferie: %s til %s", four.StartDay, four.EndDay)
+	}
+}
+
+// En fil, der ikke er en kalender, må ikke koste noget. Den hentes på et skema
+// uden nogen, der kigger med, og en fejl her ville være en sweep, der stopper.
+func TestParseCalendarSurvivesRubbish(t *testing.T) {
+	for _, body := range []string{
+		"",
+		"ikke en kalender overhovedet",
+		"BEGIN:VCALENDAR\r\nEND:VCALENDAR\r\n",
+		"BEGIN:VEVENT\r\nDTSTART:x\r\nEND:VEVENT\r\n",
+		"BEGIN:VEVENT\r\nUID:a\r\nDTSTART:2026\r\nEND:VEVENT\r\n",
+	} {
+		if got := ParseCalendar(body); len(got.Events) != 0 {
+			t.Errorf("%q gav %d begivenheder", body, len(got.Events))
+		}
+	}
+}

internal/imap/imap.go

@@ -310,3 +310,61 @@ func cut(text string) string {
 	}
 	return text
 }
+
+// Unflag takes the flag off the messages that have become tasks.
+//
+// This is what stops the same mail arriving twice, and it replaces a marker that
+// could not be made to hold. The marker was a uid: remember the highest one seen,
+// start above it next time. That is correct only if uids are what the server says
+// they are, and it broke in every way such a scheme can — a fetch reply without a
+// uid, a UIDVALIDITY that changed under a rebuilt mailbox, two mailbox rows
+// pointing at the same folder and each keeping its own marker. Every one of those
+// produced the same symptom: the same mail became a task again, and again.
+//
+// Unflagging moves the record out of our database and into the mailbox, where the
+// question is asked. "Flagged" means "turn this into a task"; once it is a task,
+// the flag has done its job and is not true any more. Nothing has to be
+// remembered, so there is nothing to get out of step — a second sync, a second
+// mailbox row, or a database restored from a backup all find the same answer,
+// because the answer is in the mailbox.
+//
+// It is destructive in the small way that matters: it changes something in
+// somebody's mail. That is the trade, and it is the right way round — a flag is a
+// note to self that this needs doing, and it has been done.
+//
+// The folder is re-selected writable. Since() opens it read-only on purpose, and
+// a search should not need write access just because a later step might.
+func (c *Client) Unflag(uids []uint32) error {
+	if len(uids) == 0 {
+		return nil
+	}
+	if _, err := c.c.Select(c.folder, nil).Wait(); err != nil {
+		return fmt.Errorf("open %s for writing: %w", c.folder, err)
+	}
+
+	set := imap.UIDSetNum()
+	for _, u := range uids {
+		if u == 0 {
+			// No uid means nothing to address. The message keeps its flag and will
+			// be seen again — which is the failure this whole function exists to
+			// prevent, so it is worth saying rather than skipping quietly.
+			continue
+		}
+		set.AddNum(imap.UID(u))
+	}
+	if len(set) == 0 {
+		return nil
+	}
+
+	// Silent: the server has nothing to tell us that we would act on, and the
+	// untagged replies would only have to be collected and thrown away.
+	cmd := c.c.Store(set, &imap.StoreFlags{
+		Op:     imap.StoreFlagsDel,
+		Silent: true,
+		Flags:  []imap.Flag{imap.FlagFlagged},
+	}, nil)
+	if err := cmd.Close(); err != nil {
+		return fmt.Errorf("unflag in %s: %w", c.folder, err)
+	}
+	return nil
+}

internal/imap/roundtrip_test.go

@@ -316,3 +316,81 @@ func TestNothingAtOrBelowTheMarkerComesBack(t *testing.T) {
 		}
 	}
 }
+
+// Den samme mail må ikke kunne blive en opgave to gange.
+//
+// Prøven kører hele vejen imod en rigtig server: den finder de flagede mails,
+// tager flaget af dem, og spørger så forfra som en ny synkronisering ville — med
+// markøren sat til nul, altså det værst tænkelige tilfælde, hvor alt, hvad vi
+// selv havde husket, er væk. Der skal ikke komme noget tilbage.
+//
+// Det er det, markøren ikke kunne love. Den holdt kun, hvis uids var, hvad
+// serveren sagde, og fejlede på et fetch-svar uden uid, på en UIDVALIDITY, der
+// skiftede, og på to postkasse-rækker, der pegede samme sted og hver især førte
+// deres eget regnskab. Alle tre gav det samme: mailen blev en opgave igen.
+func TestAnUnflaggedMailDoesNotComeBack(t *testing.T) {
+	addr, pool := serveMailbox(t, []mail{
+		{subject: "Faktura 4711", from: "[email protected]", body: "Vedhæftet.", flagged: true},
+		{subject: "Nyhedsbrev", from: "[email protected]", body: "Læs mere", flagged: false},
+		{subject: "Kontrakt", from: "[email protected]", body: "Til underskrift", flagged: true},
+	})
+
+	client, err := Dial(Account{Host: addr, Username: "kw", Password: "hemmelig", RootCAs: pool})
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer client.Close()
+
+	msgs, _, err := client.Since(0, 25)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(msgs) != 2 {
+		t.Fatalf("fandt %d flagede mails, ventede 2", len(msgs))
+	}
+
+	uids := make([]uint32, 0, len(msgs))
+	for _, m := range msgs {
+		uids = append(uids, m.UID)
+	}
+	if err := client.Unflag(uids); err != nil {
+		t.Fatalf("Unflag: %v", err)
+	}
+
+	// Forfra, og fra nul: selv en instans, der intet husker, må ikke finde dem igen.
+	again, _, err := client.Since(0, 25)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(again) != 0 {
+		t.Fatalf("%d mails kom igen efter at flaget var taget af — den første af dem er %q",
+			len(again), again[0].Subject)
+	}
+}
+
+// Et tomt kald må ikke åbne mappen skrivbar for ingenting.
+func TestUnflagWithNothingToDoIsQuiet(t *testing.T) {
+	addr, pool := serveMailbox(t, []mail{
+		{subject: "Faktura", from: "[email protected]", body: "x", flagged: true},
+	})
+	client, err := Dial(Account{Host: addr, Username: "kw", Password: "hemmelig", RootCAs: pool})
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer client.Close()
+
+	if err := client.Unflag(nil); err != nil {
+		t.Errorf("Unflag(nil) = %v", err)
+	}
+	// Kun nuller: der er intet at adressere, og mailen skal beholde sit flag.
+	if err := client.Unflag([]uint32{0, 0}); err != nil {
+		t.Errorf("Unflag(nuller) = %v", err)
+	}
+	msgs, _, err := client.Since(0, 25)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(msgs) != 1 {
+		t.Errorf("mailen mistede sit flag, uden at nogen havde adresseret den")
+	}
+}

internal/jobs/jobs.go

@@ -41,10 +41,19 @@ type Runner struct {
 	// reason as SyncGmail: it owns turning a message into a task.
 	SyncMailbox func(ctx context.Context, user *store.User, m *store.Mailbox) (int, error)
 
+	// SyncCalendars refreshes one person's connected calendars. Supplied the same
+	// way and for the same reason: the HTTP layer owns the token refresh.
+	SyncCalendars func(ctx context.Context, user *store.User) (int, error)
+
 	// Push delivers a notification to somebody's devices. Supplied by the HTTP
 	// layer, which owns the VAPID keys and the subscription list.
 	Push func(userID, title, body, projectID string)
 
+	// SendBeacon reports this installation to the collector, if it is switched on
+	// and a day has passed. Supplied by the HTTP layer for the same reason as the
+	// syncs: that is where the instance settings and the version live.
+	SendBeacon func(ctx context.Context) error
+
 	wg sync.WaitGroup
 }
 
@@ -69,6 +78,17 @@ func (r *Runner) Start(ctx context.Context) {
 	// account for a to-do app. Ten minutes is fast enough for something somebody
 	// starred and slow enough not to look like abuse.
 	r.every(ctx, "mailboxes", 10*time.Minute, r.syncMailboxes)
+	// Fifteen minutes rather than ten. A calendar is not a mailbox: nothing here
+	// becomes a task, so being a quarter of an hour behind on a meeting next
+	// Tuesday costs nothing — and the "fetch now" button covers the one case where
+	// it matters, which is somebody who has just moved something and is looking at
+	// the grid to check. A person who has just connected does not wait for this
+	// either; connecting fetches the list, and the first sync is one click away.
+	r.every(ctx, "calendars", 15*time.Minute, r.syncCalendars)
+	// Checked hourly, sent at most daily — the same shape as the backup, and for
+	// the same reason: a container asleep at the scheduled minute would otherwise
+	// skip the day. SendBeacon decides whether a day has passed.
+	r.every(ctx, "beacon", time.Hour, r.sendBeacon)
 }
 
 func (r *Runner) Wait() { r.wg.Wait() }
@@ -103,6 +123,17 @@ func (r *Runner) every(ctx context.Context, name string, interval time.Duration,
 	}()
 }
 
+// sendBeacon reports that this installation exists, at most once a day.
+//
+// Every decision about what is sent, and why this is on by default rather than
+// compulsory, lives in internal/beacon. This is only the clock.
+func (r *Runner) sendBeacon(ctx context.Context) error {
+	if r.SendBeacon == nil {
+		return nil
+	}
+	return r.SendBeacon(ctx)
+}
+
 // --- reminders ------------------------------------------------------------------
 
 // sendDueReminders delivers everything that has come due since the last pass.
@@ -322,6 +353,44 @@ func (r *Runner) syncMailboxes(ctx context.Context) error {
 	return nil
 }
 
+// --- calendars ------------------------------------------------------------------------
+
+// syncCalendars refreshes everybody's connected calendars.
+//
+// Its own sweep rather than a branch inside the mailbox one. They share nothing
+// past the word "poll": that loop asks each mailbox how far it has read and makes
+// tasks, this one replaces a window of somebody else's events. Folding them
+// together would mean one interval for two questions that do not want the same
+// answer, and a Google that is down would count against a mailbox that is not.
+//
+// Nobody is waiting, so no budget of its own — the request handler has one because
+// a person is watching a spinner. One account that has gone quiet costs this run
+// its own timeout and nothing else: the loop moves on per person.
+func (r *Runner) syncCalendars(ctx context.Context) error {
+	if r.SyncCalendars == nil {
+		return nil
+	}
+	userIDs, err := r.db.UsersWithCalendars(ctx)
+	if err != nil {
+		return err
+	}
+	for _, id := range userIDs {
+		user, err := r.db.UserByID(ctx, id)
+		if err != nil || user == nil {
+			continue
+		}
+		written, err := r.SyncCalendars(ctx, user)
+		if err != nil {
+			r.log.Warn("calendar sync", "err", err, "user", id)
+			continue
+		}
+		if written > 0 {
+			r.log.Info("calendar refreshed", "user", id, "events", written)
+		}
+	}
+	return nil
+}
+
 // --- housekeeping -----------------------------------------------------------------
 
 func (r *Runner) emptyTrash(ctx context.Context) error {

internal/push/push.go

@@ -32,6 +32,8 @@ import (
 	"net/url"
 	"strings"
 	"time"
+
+	"github.com/kristianwind/verdande/internal/safedial"
 )
 
 type Subscription struct {
@@ -101,7 +103,19 @@ func Send(ctx context.Context, sub Subscription, payload Payload, vapid VAPID) e
 	req.Header.Set("Urgency", "normal")
 	req.Header.Set("Authorization", "vapid t="+token+", k="+vapid.Public)
 
-	resp, err := (&http.Client{Timeout: 15 * time.Second}).Do(req)
+	// safedial, not a plain client. The endpoint comes from the browser's
+	// subscription, which is to say from whoever is signed in, and this server
+	// POSTs to it on a schedule they choose — set a reminder a minute out and the
+	// job goes again every minute.
+	//
+	// The subscribe handler already refuses a private address, and that check is
+	// not enough on its own: it runs on the URL as written, and a name it approves
+	// can answer 127.0.0.1 the next time it is looked up. safedial checks the
+	// *resolved* address at connect time, which is the only moment the address
+	// that will actually be used is known — and it checks every redirect hop the
+	// same way. The parse-time check stays, because it says no while somebody is
+	// looking at the screen.
+	resp, err := safedial.Client(15 * time.Second).Do(req)
 	if err != nil {
 		return err
 	}

internal/push/push_test.go

@@ -0,0 +1,66 @@
+package push
+
+import (
+	"context"
+	"crypto/ecdh"
+	"crypto/rand"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+)
+
+// A subscription must not be able to point the server at its own network.
+//
+// The endpoint is whatever the browser handed over, which is to say whatever the
+// person signed in handed over, and this server POSTs to it on a schedule they
+// choose. The subscribe handler refuses a private address when it is written
+// down — and that check runs on the URL as written, so a name it approves can
+// answer 127.0.0.1 the next time it is looked up. This is the other half: the
+// address that will actually be dialled, checked at the moment of dialling.
+func TestSendRefusesToReachInside(t *testing.T) {
+	reached := false
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		reached = true
+		w.WriteHeader(http.StatusCreated)
+	}))
+	defer srv.Close()
+	// httptest listens on 127.0.0.1, which is exactly the destination in question.
+	if !strings.Contains(srv.URL, "127.0.0.1") {
+		t.Skipf("the test server is not on loopback: %s", srv.URL)
+	}
+
+	err := Send(context.Background(), testSubscription(t, srv.URL), Payload{Title: "hej"}, testVAPID(t))
+	if err == nil {
+		t.Fatal("Send reached a loopback address without complaining")
+	}
+	if reached {
+		t.Error("the request arrived: the wall let it through and only the answer failed")
+	}
+}
+
+func testSubscription(t *testing.T, endpoint string) Subscription {
+	t.Helper()
+	key, err := ecdh.P256().GenerateKey(rand.Reader)
+	if err != nil {
+		t.Fatal(err)
+	}
+	auth := make([]byte, 16)
+	if _, err := rand.Read(auth); err != nil {
+		t.Fatal(err)
+	}
+	return Subscription{
+		Endpoint: endpoint,
+		P256dh:   b64.EncodeToString(key.PublicKey().Bytes()),
+		Auth:     b64.EncodeToString(auth),
+	}
+}
+
+func testVAPID(t *testing.T) VAPID {
+	t.Helper()
+	pub, priv, err := GenerateVAPIDKeys()
+	if err != nil {
+		t.Fatal(err)
+	}
+	return VAPID{Public: pub, Private: priv, Subject: "mailto:[email protected]"}
+}

internal/safedial/safedial.go

@@ -0,0 +1,136 @@
+// Package safedial refuses to open a connection to this machine or to the
+// network it sits on.
+//
+// The problem it solves is the same one three times: somewhere a user supplies a
+// URL or a host, and the server fetches it. An AI provider's base address, a push
+// endpoint, an IMAP host, a beacon collector. Each of them is a feature, and each
+// of them is also a way to ask the server to reach something the caller cannot —
+// the panel next door, a metadata endpoint, a database on the same bridge — and
+// to report back whether it answered. On a homelab that is the whole point of the
+// box being where it is.
+//
+// # Why the check is on the address and not on the URL
+//
+// Parsing the URL and refusing "localhost" or "127.0.0.1" is the obvious version
+// and it does not work: a name resolves to whatever its owner says, so
+// `evil.example.com` can answer 127.0.0.1 — and can answer differently the second
+// time, after a parse-time check has passed. That is DNS rebinding, and the only
+// place it can be caught is after resolution and before the connection, which is
+// exactly where net.Dialer's Control hook runs.
+//
+// # What is refused
+//
+// Loopback, link-local (including 169.254.169.254, which is where cloud metadata
+// lives), the private ranges, unique-local IPv6, and the unspecified address.
+// Everything else is allowed: this is not an allowlist of the internet, it is a
+// wall around the inside.
+package safedial
+
+import (
+	"fmt"
+	"net"
+	"net/http"
+	"net/url"
+	"syscall"
+	"time"
+)
+
+// ErrPrivate is returned when a connection was refused for where it pointed. It
+// deliberately does not say which address it resolved to: the answer is itself
+// the thing an attacker is fishing for.
+type ErrPrivate struct{ Host string }
+
+func (e *ErrPrivate) Error() string {
+	return fmt.Sprintf("refusing to connect to %s: it resolves to an address on this machine or its private network", e.Host)
+}
+
+// Blocked reports whether an address must not be dialled.
+func Blocked(ip net.IP) bool {
+	return ip == nil ||
+		ip.IsLoopback() ||
+		ip.IsUnspecified() ||
+		ip.IsLinkLocalUnicast() ||
+		ip.IsLinkLocalMulticast() ||
+		ip.IsInterfaceLocalMulticast() ||
+		ip.IsMulticast() ||
+		ip.IsPrivate()
+}
+
+// Control is a net.Dialer Control function that refuses a private destination.
+//
+// It runs after the name has been resolved and before the socket is connected,
+// which is the only moment where the address that will actually be used is known.
+func Control(network, address string, _ syscall.RawConn) error {
+	host, _, err := net.SplitHostPort(address)
+	if err != nil {
+		return err
+	}
+	ip := net.ParseIP(host)
+	if Blocked(ip) {
+		return &ErrPrivate{Host: host}
+	}
+	return nil
+}
+
+// Dialer is a net.Dialer that will not reach inside.
+func Dialer(timeout time.Duration) *net.Dialer {
+	return &net.Dialer{Timeout: timeout, Control: Control}
+}
+
+// Client is an http.Client for fetching something a user named.
+//
+// Redirects are followed but capped, and every hop goes through the same dialer —
+// a redirect to 127.0.0.1 is the oldest way around a check that only looked at the
+// URL somebody typed.
+func Client(timeout time.Duration) *http.Client {
+	return &http.Client{
+		Timeout: timeout,
+		Transport: &http.Transport{
+			DialContext:           Dialer(timeout).DialContext,
+			TLSHandshakeTimeout:   timeout,
+			ResponseHeaderTimeout: timeout,
+		},
+		CheckRedirect: func(req *http.Request, via []*http.Request) error {
+			if len(via) >= 5 {
+				return fmt.Errorf("too many redirects")
+			}
+			return nil
+		},
+	}
+}
+
+// AllowPrivate is the same client without the wall, for a destination the
+// operator configured rather than a user — the panel, and nothing else. Named so
+// that using it is a decision somebody wrote down.
+func AllowPrivate(timeout time.Duration) *http.Client {
+	return &http.Client{Timeout: timeout}
+}
+
+// CheckURL reports why an address must not be fetched, or "" if it may be.
+//
+// A convenience for saying no at the moment somebody types an address, rather
+// than later when a request quietly fails. It is NOT the protection — a name can
+// resolve one way now and another way when it is dialled, which is why Control
+// exists and runs every time. Anything this rejects is certainly wrong; anything
+// it accepts is merely not obviously wrong.
+func CheckURL(raw string) string {
+	u, err := url.Parse(raw)
+	if err != nil || u.Host == "" {
+		return "that is not a URL"
+	}
+	host := u.Hostname()
+	if ip := net.ParseIP(host); ip != nil && Blocked(ip) {
+		return "that address is on this machine or its private network"
+	}
+	// A bare name is looked up once so an obvious "localhost" is caught here. A
+	// failure to resolve is not an error: the host may simply not exist yet, and
+	// refusing to save an address because DNS was slow would be its own bug.
+	if ips, err := net.LookupIP(host); err == nil {
+		for _, ip := range ips {
+			if Blocked(ip) {
+				return "that address is on this machine or its private network"
+			}
+		}
+	}
+	return ""
+}

internal/safedial/safedial_test.go

@@ -0,0 +1,55 @@
+package safedial
+
+import (
+	"net"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+	"time"
+)
+
+func TestBlockedCoversTheInside(t *testing.T) {
+	blocked := []string{
+		"127.0.0.1", "::1", "0.0.0.0",
+		// Skyens metadata-endepunkt. Den ene adresse, enhver SSRF sigter efter.
+		"169.254.169.254",
+		"10.0.0.5", "172.16.0.1", "192.168.1.10", "fd00::1", "fe80::1",
+	}
+	for _, s := range blocked {
+		if !Blocked(net.ParseIP(s)) {
+			t.Errorf("Blocked(%s) = false", s)
+		}
+	}
+	for _, s := range []string{"93.184.216.34", "8.8.8.8", "2606:2800:220:1:248:1893:25c8:1946"} {
+		if Blocked(net.ParseIP(s)) {
+			t.Errorf("Blocked(%s) = true, men det er en almindelig adresse", s)
+		}
+	}
+}
+
+// En httptest-server lytter på loopback, hvilket gør den til den perfekte prøve:
+// den findes, den svarer, og den må ikke kunne nås.
+func TestClientRefusesLoopback(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		t.Error("forbindelsen blev oprettet; den skulle være afvist")
+	}))
+	defer srv.Close()
+
+	_, err := Client(3 * time.Second).Get(srv.URL)
+	if err == nil {
+		t.Fatal("en forespørgsel til loopback skal afvises")
+	}
+}
+
+func TestAllowPrivateStillReaches(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusNoContent)
+	}))
+	defer srv.Close()
+
+	resp, err := AllowPrivate(3 * time.Second).Get(srv.URL)
+	if err != nil {
+		t.Fatalf("den skal kunne nå det, operatøren selv har peget på: %v", err)
+	}
+	resp.Body.Close()
+}

internal/store/beacon.go

@@ -0,0 +1,138 @@
+package store
+
+import (
+	"context"
+	"time"
+)
+
+// The collector's side of the beacon: what has reported in, and how many.
+//
+// Every method here is about counting installations, never about identifying one.
+// There is no lookup by anything but the id an installation made up for itself,
+// and there is nothing to join it against.
+
+// BeaconStats is the whole of what the collector can say.
+type BeaconStats struct {
+	Total      int            `json:"total"`
+	Active7d   int            `json:"active_7d"`
+	Active30d  int            `json:"active_30d"`
+	ByVersion  map[string]int `json:"by_version"`
+	LastPingAt *time.Time     `json:"last_ping_at,omitempty"`
+}
+
+// maxBeaconInstalls bounds the table.
+//
+// The receiving endpoint is unauthenticated — it has to be, since the caller is a
+// stranger's installation — and it inserts a row keyed on an id the caller made
+// up. Anybody can therefore mint ids and grow this table until the volume the
+// database lives on is full. A ceiling turns that from a disk-fill into a number
+// that is merely wrong, which is the difference between an outage and an
+// annoyance. A hundred thousand is far above any plausible real count and far
+// below anything that matters on disk.
+const maxBeaconInstalls = 100_000
+
+// RecordBeacon writes down that an installation is alive, and on which version.
+//
+// `first_seen` is kept from the original row on purpose: it is the only thing
+// that distinguishes an installation that has been running for a year from one
+// that appeared this morning, and it costs nothing to keep.
+func (db *DB) RecordBeacon(ctx context.Context, instanceID, version string) error {
+	now := time.Now().Unix()
+
+	// An installation already known keeps reporting whatever the ceiling says: the
+	// cap must never stop counting the real ones, only stop new rows from being
+	// invented without limit.
+	var known int
+	if err := db.QueryRowContext(ctx,
+		`SELECT count(*) FROM beacon_installs WHERE instance_id = ?`, instanceID).Scan(&known); err != nil {
+		return err
+	}
+	if known == 0 {
+		var total int
+		if err := db.QueryRowContext(ctx,
+			`SELECT count(*) FROM beacon_installs`).Scan(&total); err != nil {
+			return err
+		}
+		if total >= maxBeaconInstalls {
+			// Not an error to the caller. Their installation did nothing wrong, and
+			// there is nothing for them to do about it.
+			return nil
+		}
+	}
+
+	_, err := db.ExecContext(ctx, `
+		INSERT INTO beacon_installs (instance_id, version, first_seen, last_seen)
+		VALUES (?, ?, ?, ?)
+		ON CONFLICT (instance_id) DO UPDATE SET
+		    version   = excluded.version,
+		    last_seen = excluded.last_seen`,
+		instanceID, version, now, now)
+	return err
+}
+
+// BeaconCount is how many installations have reported within the window.
+//
+// A window rather than a running total, and that is not a detail. A total only
+// ever climbs: every instance anybody ever started for ten minutes stays in it
+// forever, so the number stops meaning "how many people use this" and starts
+// meaning "how many people have ever tried it". The question being asked is the
+// first one.
+func (db *DB) BeaconCount(ctx context.Context, within time.Duration) (int, error) {
+	var n int
+	err := db.QueryRowContext(ctx,
+		`SELECT count(*) FROM beacon_installs WHERE last_seen >= ?`,
+		time.Now().Add(-within).Unix()).Scan(&n)
+	return n, err
+}
+
+// BeaconSummary is everything the settings page shows.
+func (db *DB) BeaconSummary(ctx context.Context) (BeaconStats, error) {
+	out := BeaconStats{ByVersion: map[string]int{}}
+
+	if err := db.QueryRowContext(ctx,
+		`SELECT count(*) FROM beacon_installs`).Scan(&out.Total); err != nil {
+		return out, err
+	}
+
+	var err error
+	if out.Active7d, err = db.BeaconCount(ctx, 7*24*time.Hour); err != nil {
+		return out, err
+	}
+	if out.Active30d, err = db.BeaconCount(ctx, 30*24*time.Hour); err != nil {
+		return out, err
+	}
+
+	// Versions of the ones still alive, not of everything ever seen: an instance
+	// that stopped reporting two years ago should not still be counted as running
+	// the version it was on when it stopped.
+	rows, err := db.QueryContext(ctx, `
+		SELECT version, count(*) FROM beacon_installs
+		 WHERE last_seen >= ? AND version <> ''
+		 GROUP BY version`, time.Now().Add(-30*24*time.Hour).Unix())
+	if err != nil {
+		return out, err
+	}
+	defer rows.Close()
+	for rows.Next() {
+		var v string
+		var n int
+		if err := rows.Scan(&v, &n); err != nil {
+			return out, err
+		}
+		out.ByVersion[v] = n
+	}
+	if err := rows.Err(); err != nil {
+		return out, err
+	}
+
+	var last *int64
+	if err := db.QueryRowContext(ctx,
+		`SELECT max(last_seen) FROM beacon_installs`).Scan(&last); err != nil {
+		return out, err
+	}
+	if last != nil {
+		t := time.Unix(*last, 0)
+		out.LastPingAt = &t
+	}
+	return out, nil
+}

internal/store/calendars.go

@@ -0,0 +1,531 @@
+package store
+
+import (
+	"context"
+	"database/sql"
+	"errors"
+	"fmt"
+	"strings"
+	"time"
+)
+
+// CalendarAccount is one connected account belonging to one person.
+type CalendarAccount struct {
+	ID       string `json:"id"`
+	UserID   string `json:"-"`
+	Provider string `json:"provider"`
+	Account  string `json:"account,omitempty"`
+
+	// URL er tom for en OAuth-konto og adressen for et abonnement. Den er
+	// identiteten på et abonnement, som tokenet er det for Google: to rækker med
+	// den samme adresse for den samme person ville være den samme kalender hentet
+	// to gange, uden nogen måde at sige hvilken der gælder.
+	URL string `json:"url,omitempty"`
+
+	RefreshToken string    `json:"-"` // never leaves the server
+	AccessToken  string    `json:"-"`
+	ExpiresAt    time.Time `json:"-"`
+
+	LastSyncAt time.Time `json:"last_sync_at,omitempty"`
+	CreatedAt  time.Time `json:"created_at"`
+}
+
+// Calendar is one calendar inside an account, shown or not.
+type Calendar struct {
+	ID        string `json:"id"`
+	AccountID string `json:"-"`
+	RemoteID  string `json:"remote_id"`
+	Name      string `json:"name"`
+	Colour    string `json:"colour,omitempty"`
+	TimeZone  string `json:"time_zone,omitempty"`
+	Primary   bool   `json:"primary"`
+	// Writable says the connected account could write to it. Nothing does — the
+	// scope is read-only — and it is stored so the day something can, the interface
+	// knows which calendars could even be offered.
+	Writable  bool `json:"writable"`
+	Shown     bool `json:"shown"`
+	SortOrder int  `json:"-"`
+}
+
+// CalendarEvent is one occurrence, in the shape a grid asks about: days at both
+// ends, inclusive.
+type CalendarEvent struct {
+	ID         string `json:"id"`
+	CalendarID string `json:"calendar_id"`
+	RemoteID   string `json:"-"`
+	Summary    string `json:"summary"`
+	StartsAt   string `json:"starts_at,omitempty"`
+	EndsAt     string `json:"ends_at,omitempty"`
+	StartDay   string `json:"start_day"`
+	EndDay     string `json:"end_day"`
+	AllDay     bool   `json:"all_day"`
+	Location   string `json:"location,omitempty"`
+	URL        string `json:"url,omitempty"`
+
+	// CalendarName and Colour ride along with the event rather than being looked up
+	// per row by the caller. Same reasoning as the assignee names on a task list:
+	// the chip has to be drawn in the calendar's own colour, and a second request
+	// per event to learn it is a request per event.
+	CalendarName string `json:"calendar_name,omitempty"`
+	Colour       string `json:"colour,omitempty"`
+}
+
+const calendarAccountColumns = `id, user_id, provider, account, refresh_token,
+	access_token, expires_at, last_sync_at, created_at`
+
+// Med adressen. Skrivningen tilføjer den selv, fordi indsættelsen navngiver
+// søjlerne; læsningen skal bede om den.
+const calendarAccountRead = calendarAccountColumns + `, url`
+
+// CalendarAccountFor returns a person's connection to one provider, or nil.
+func (db *DB) CalendarAccountFor(ctx context.Context, userID, provider string) (*CalendarAccount, error) {
+	// `url = ''`: en OAuth-konto. Uden det ville et abonnement hos den samme
+	// udbyder kunne svare på spørgsmålet "hvad er personen forbundet til med
+	// Google", og et abonnement har hverken token eller konto at svare med.
+	row := db.QueryRowContext(ctx, `SELECT `+calendarAccountRead+`
+		FROM calendar_accounts WHERE user_id = ? AND provider = ? AND url = ''`, userID, provider)
+	a, err := db.scanCalendarAccount(row)
+	if err == sql.ErrNoRows {
+		return nil, nil
+	}
+	if err != nil {
+		return nil, err
+	}
+	return &a, nil
+}
+
+// SaveCalendarAccount writes one, sealing the two columns that must not travel
+// with a backup. Called by hand rather than by the settings tables' own seal,
+// which does not reach this table.
+func (db *DB) SaveCalendarAccount(ctx context.Context, a *CalendarAccount) error {
+	if a.ID == "" {
+		a.ID = NewID()
+	}
+	if a.Provider == "" {
+		a.Provider = "google"
+	}
+	if a.CreatedAt.IsZero() {
+		a.CreatedAt = time.Now()
+	}
+
+	refresh, err := db.sealValue(a.RefreshToken)
+	if err != nil {
+		return fmt.Errorf("seal refresh_token: %w", err)
+	}
+	access, err := db.sealValue(a.AccessToken)
+	if err != nil {
+		return fmt.Errorf("seal access_token: %w", err)
+	}
+
+	// The conflict is on the pair, not on the id: a reconnect builds a fresh
+	// struct with no id in it, and matching on the id would insert a second row
+	// that the unique index then refuses — which reads to the person as "connecting
+	// failed" when what happened is that it already had.
+	// `WHERE url = ''` fordi indekset er delvist siden 0026.
+	//
+	// En OAuth-konto er én pr. person og udbyder — det er tokenet, der er
+	// identiteten — mens et abonnement er én pr. adresse, og man har flere. De to
+	// bor i samme tabel, fordi et abonnement *er* en kalender med begivenheder i,
+	// og den halvdel er den samme. Målet for konflikten skal sige, hvilken af de to
+	// slags rækker der tales om, ellers ved SQLite det ikke.
+	_, err = db.ExecContext(ctx, `
+		INSERT INTO calendar_accounts (`+calendarAccountColumns+`, url)
+		VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
+		ON CONFLICT (user_id, provider) WHERE url = '' DO UPDATE SET
+		    account = excluded.account,
+		    refresh_token = excluded.refresh_token,
+		    access_token = excluded.access_token,
+		    expires_at = excluded.expires_at,
+		    last_sync_at = excluded.last_sync_at`,
+		a.ID, a.UserID, a.Provider, a.Account, refresh, access,
+		unixOrZero(a.ExpiresAt), unixOrZero(a.LastSyncAt), a.CreatedAt.Unix(), a.URL)
+	if err != nil {
+		return err
+	}
+	if a.URL != "" {
+		return nil
+	}
+
+	// The row that is actually there wins. On a reconnect the insert above updated
+	// an existing row, so the id in hand is one nothing points at — and the
+	// calendars are hung off the id, so writing them against it would attach them
+	// to nothing.
+	return db.QueryRowContext(ctx,
+		`SELECT id FROM calendar_accounts WHERE user_id = ? AND provider = ? AND url = ''`,
+		a.UserID, a.Provider).Scan(&a.ID)
+}
+
+// MarkCalendarSynced records how far a run got. Written separately from the rest
+// so a sync never rewrites the credentials it is holding in memory.
+func (db *DB) MarkCalendarSynced(ctx context.Context, accountID string, at time.Time) error {
+	_, err := db.ExecContext(ctx,
+		`UPDATE calendar_accounts SET last_sync_at = ? WHERE id = ?`, at.Unix(), accountID)
+	return err
+}
+
+// DeleteCalendarAccount disconnects one. The calendars and their events go with it
+// — unlike the tasks a mailbox made, none of this is the person's own work; it is
+// a copy of somebody else's calendar and it has no meaning without the account.
+func (db *DB) DeleteCalendarAccount(ctx context.Context, userID, id string) error {
+	_, err := db.ExecContext(ctx,
+		`DELETE FROM calendar_accounts WHERE id = ? AND user_id = ?`, id, userID)
+	return err
+}
+
+// UsersWithCalendars returns everybody the sweep has to visit.
+func (db *DB) UsersWithCalendars(ctx context.Context) ([]string, error) {
+	rows, err := db.QueryContext(ctx, `SELECT DISTINCT user_id FROM calendar_accounts`)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	var ids []string
+	for rows.Next() {
+		var id string
+		if err := rows.Scan(&id); err != nil {
+			return nil, err
+		}
+		ids = append(ids, id)
+	}
+	return ids, rows.Err()
+}
+
+// Calendars returns what one account holds, in the order the provider listed them.
+func (db *DB) Calendars(ctx context.Context, accountID string) ([]Calendar, error) {
+	rows, err := db.QueryContext(ctx, `
+		SELECT id, account_id, remote_id, name, colour, time_zone, primary_one,
+		       writable, shown, sort_order
+		FROM calendars WHERE account_id = ? ORDER BY sort_order, name`, accountID)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	var out []Calendar
+	for rows.Next() {
+		var c Calendar
+		if err := rows.Scan(&c.ID, &c.AccountID, &c.RemoteID, &c.Name, &c.Colour,
+			&c.TimeZone, &c.Primary, &c.Writable, &c.Shown, &c.SortOrder); err != nil {
+			return nil, err
+		}
+		out = append(out, c)
+	}
+	return out, rows.Err()
+}
+
+// ReplaceCalendars writes the list the provider just gave, keeping what the person
+// chose.
+//
+// The choice survives because it is not in the list: Google says which calendars
+// exist and what they are called, and only verdande knows which of them somebody
+// wants to look at. Merged rather than deleted and rewritten, so ticking a calendar
+// on does not come undone the next time the sweep runs.
+//
+// A calendar that has disappeared from the account is removed, and its events go
+// with it — a calendar somebody was unshared from should stop being drawn, not
+// stay behind as a frozen copy of what it held on the last good day.
+func (db *DB) ReplaceCalendars(ctx context.Context, accountID string, list []Calendar) error {
+	return db.Tx(ctx, func(tx *sql.Tx) error {
+		keep := map[string]bool{}
+		for i, c := range list {
+			keep[c.RemoteID] = true
+			// The insert cannot carry `shown`: on conflict it would overwrite the
+			// choice with the default. A new calendar starts hidden — an account
+			// with a dozen shared calendars in it should not fill somebody's grid
+			// the moment they connect it.
+			if _, err := tx.ExecContext(ctx, `
+				INSERT INTO calendars
+				    (id, account_id, remote_id, name, colour, time_zone, primary_one,
+				     writable, shown, sort_order)
+				VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
+				ON CONFLICT (account_id, remote_id) DO UPDATE SET
+				    name = excluded.name,
+				    colour = excluded.colour,
+				    time_zone = excluded.time_zone,
+				    primary_one = excluded.primary_one,
+				    writable = excluded.writable,
+				    sort_order = excluded.sort_order`,
+				NewID(), accountID, c.RemoteID, c.Name, c.Colour, c.TimeZone,
+				c.Primary, c.Writable, c.Shown, i); err != nil {
+				return err
+			}
+		}
+
+		rows, err := tx.QueryContext(ctx,
+			`SELECT id, remote_id FROM calendars WHERE account_id = ?`, accountID)
+		if err != nil {
+			return err
+		}
+		var gone []string
+		for rows.Next() {
+			var id, remote string
+			if err := rows.Scan(&id, &remote); err != nil {
+				rows.Close()
+				return err
+			}
+			if !keep[remote] {
+				gone = append(gone, id)
+			}
+		}
+		// Closed before the next statement runs on this transaction. An open result
+		// set with a query behind it is the deadlock the pool comment in store.go
+		// exists to make slow rather than fatal.
+		rows.Close()
+		if err := rows.Err(); err != nil {
+			return err
+		}
+
+		for _, id := range gone {
+			if _, err := tx.ExecContext(ctx, `DELETE FROM calendars WHERE id = ?`, id); err != nil {
+				return err
+			}
+		}
+		return nil
+	})
+}
+
+// ShowCalendars sets which of an account's calendars are drawn.
+//
+// The whole set in one write rather than one flip at a time, for the reason the
+// projects' order is written the same way: a person has a handful of calendars, the
+// question is "these ones", and a list that can only be built by several requests
+// can land half applied.
+func (db *DB) ShowCalendars(ctx context.Context, accountID string, shown []string) error {
+	return db.Tx(ctx, func(tx *sql.Tx) error {
+		if _, err := tx.ExecContext(ctx,
+			`UPDATE calendars SET shown = 0 WHERE account_id = ?`, accountID); err != nil {
+			return err
+		}
+		for _, id := range shown {
+			// Scoped in the SQL rather than checked first: an id read in one step
+			// and written in the next is a window, and the account is the whole of
+			// the permission here.
+			if _, err := tx.ExecContext(ctx,
+				`UPDATE calendars SET shown = 1 WHERE id = ? AND account_id = ?`,
+				id, accountID); err != nil {
+				return err
+			}
+		}
+		// Events of a calendar nobody is looking at are dead weight in a table the
+		// grid queries. They come back with the next sync if it is turned on again.
+		_, err := tx.ExecContext(ctx, `
+			DELETE FROM calendar_events WHERE calendar_id IN
+			    (SELECT id FROM calendars WHERE account_id = ? AND shown = 0)`, accountID)
+		return err
+	})
+}
+
+// ReplaceCalendarEvents swaps one calendar's events inside a window.
+//
+// Replaced rather than merged, and no sync token. Google offers incremental sync,
+// and it would save bytes verdande is not short of while costing the one thing it
+// cannot afford: a token that has to be right, forever, for the grid not to be
+// quietly wrong. A window that is deleted and rewritten cannot drift — an event
+// somebody moved out of the window disappears because it is not in the answer, not
+// because verdande remembered to delete it.
+//
+// Bounded by the window at both ends, so a sync of September does not throw away
+// August.
+func (db *DB) ReplaceCalendarEvents(ctx context.Context, calendarID, from, to string, events []CalendarEvent) error {
+	return db.Tx(ctx, func(tx *sql.Tx) error {
+		if _, err := tx.ExecContext(ctx, `
+			DELETE FROM calendar_events
+			WHERE calendar_id = ? AND end_day >= ? AND start_day <= ?`,
+			calendarID, from, to); err != nil {
+			return err
+		}
+		for _, e := range events {
+			if _, err := tx.ExecContext(ctx, `
+				INSERT INTO calendar_events
+				    (id, calendar_id, remote_id, summary, starts_at, ends_at,
+				     start_day, end_day, all_day, location, url)
+				VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)`,
+				NewID(), calendarID, e.RemoteID, e.Summary, e.StartsAt, e.EndsAt,
+				e.StartDay, e.EndDay, e.AllDay, e.Location, e.URL); err != nil {
+				return err
+			}
+		}
+		return nil
+	})
+}
+
+// CalendarEvents returns everything one person can see between two days,
+// inclusive at both ends.
+//
+// Scoped to the caller in the join rather than checked afterwards: the events of
+// somebody else's calendar are somebody else's, and a filter applied after the read
+// is a filter that can be forgotten.
+func (db *DB) CalendarEvents(ctx context.Context, userID, from, to string) ([]CalendarEvent, error) {
+	rows, err := db.QueryContext(ctx, `
+		SELECT e.id, e.calendar_id, e.remote_id, e.summary, e.starts_at, e.ends_at,
+		       e.start_day, e.end_day, e.all_day, e.location, e.url, c.name, c.colour
+		FROM calendar_events e
+		JOIN calendars c ON c.id = e.calendar_id
+		JOIN calendar_accounts a ON a.id = c.account_id
+		WHERE a.user_id = ? AND c.shown = 1 AND e.end_day >= ? AND e.start_day <= ?
+		ORDER BY e.start_day, e.all_day DESC, e.starts_at`, userID, from, to)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	var out []CalendarEvent
+	for rows.Next() {
+		var e CalendarEvent
+		if err := rows.Scan(&e.ID, &e.CalendarID, &e.RemoteID, &e.Summary, &e.StartsAt,
+			&e.EndsAt, &e.StartDay, &e.EndDay, &e.AllDay, &e.Location, &e.URL,
+			&e.CalendarName, &e.Colour); err != nil {
+			return nil, err
+		}
+		out = append(out, e)
+	}
+	return out, rows.Err()
+}
+
+func (db *DB) scanCalendarAccount(row scanner) (CalendarAccount, error) {
+	var a CalendarAccount
+	var expires, lastSync, created int64
+	err := row.Scan(&a.ID, &a.UserID, &a.Provider, &a.Account, &a.RefreshToken,
+		&a.AccessToken, &expires, &lastSync, &created, &a.URL)
+	if err != nil {
+		return a, err
+	}
+	for _, field := range []*string{&a.RefreshToken, &a.AccessToken} {
+		plain, err := db.unsealValue(*field)
+		if err != nil {
+			return a, err
+		}
+		*field = plain
+	}
+	a.ExpiresAt = timeOrZero(expires)
+	a.LastSyncAt = timeOrZero(lastSync)
+	a.CreatedAt = time.Unix(created, 0)
+	return a, nil
+}
+
+// --- abonnementer ---------------------------------------------------------------
+
+// SubscribeCalendar adds a calendar somebody only has an address to.
+//
+// One row in `calendar_accounts` with a url and no tokens, and one row in
+// `calendars` hung off it — because a subscription *is* one calendar, where an
+// OAuth account is a list of them somebody picks from. Written together so a
+// subscription is never a row with nothing under it: the sweep looks for accounts,
+// and one without a calendar would be fetched for ever and stored nowhere.
+//
+// Shown from the start. Ticking a box after adding an address is a second step for
+// a decision the person already made by adding it.
+func (db *DB) SubscribeCalendar(ctx context.Context, userID, url, name string) (*CalendarAccount, error) {
+	account := &CalendarAccount{
+		ID:        NewID(),
+		UserID:    userID,
+		Provider:  "ics",
+		Account:   name,
+		URL:       url,
+		CreatedAt: time.Now(),
+	}
+
+	err := db.Tx(ctx, func(tx *sql.Tx) error {
+		if _, err := tx.ExecContext(ctx, `
+			INSERT INTO calendar_accounts (id, user_id, provider, account, url, created_at)
+			VALUES (?, ?, 'ics', ?, ?, ?)`,
+			account.ID, userID, name, url, account.CreatedAt.Unix()); err != nil {
+			return err
+		}
+		_, err := tx.ExecContext(ctx, `
+			INSERT INTO calendars (id, account_id, remote_id, name, shown)
+			VALUES (?, ?, ?, ?, 1)`,
+			NewID(), account.ID, url, name)
+		return err
+	})
+	if isUniqueViolation(err) {
+		return nil, ErrDuplicate
+	}
+	if err != nil {
+		return nil, err
+	}
+	return account, nil
+}
+
+// Subscriptions lists the calendars a person subscribes to by address.
+func (db *DB) Subscriptions(ctx context.Context, userID string) ([]CalendarAccount, error) {
+	rows, err := db.QueryContext(ctx, `SELECT `+calendarAccountRead+`
+		FROM calendar_accounts WHERE user_id = ? AND url <> ''
+		ORDER BY created_at`, userID)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	out := []CalendarAccount{}
+	for rows.Next() {
+		a, err := db.scanCalendarAccount(rows)
+		if err != nil {
+			return nil, err
+		}
+		out = append(out, a)
+	}
+	return out, rows.Err()
+}
+
+// AllSubscriptions is every subscription on the instance, for the sweep.
+//
+// The sweep runs for the server rather than for a session, so it cannot ask "whose
+// is this" the way a handler can — it is handed the user id along with the row and
+// writes against that.
+func (db *DB) AllSubscriptions(ctx context.Context) ([]CalendarAccount, error) {
+	rows, err := db.QueryContext(ctx, `SELECT `+calendarAccountRead+`
+		FROM calendar_accounts WHERE url <> '' ORDER BY last_sync_at`)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	out := []CalendarAccount{}
+	for rows.Next() {
+		a, err := db.scanCalendarAccount(rows)
+		if err != nil {
+			return nil, err
+		}
+		out = append(out, a)
+	}
+	return out, rows.Err()
+}
+
+// RenameSubscribedCalendar writes the name the file calls itself.
+//
+// A subscription is added with the address as its name, because that is all there
+// is to go on before it has been fetched once. The file usually says better —
+// X-WR-CALNAME is what every publisher uses — and taking it means the list says
+// "Danske helligdage" instead of a URL nobody reads.
+//
+// Only when the person has not renamed it themselves: a name they typed is an
+// instruction, and a name from the file is a guess.
+func (db *DB) RenameSubscribedCalendar(ctx context.Context, accountID, name string) error {
+	if strings.TrimSpace(name) == "" {
+		return nil
+	}
+	return db.Tx(ctx, func(tx *sql.Tx) error {
+		if _, err := tx.ExecContext(ctx, `
+			UPDATE calendar_accounts SET account = ?
+			WHERE id = ? AND (account = '' OR account = url)`, name, accountID); err != nil {
+			return err
+		}
+		_, err := tx.ExecContext(ctx, `
+			UPDATE calendars SET name = ?
+			WHERE account_id = ? AND (name = '' OR name = remote_id)`, name, accountID)
+		return err
+	})
+}
+
+// SubscribedCalendarID is the single calendar row under a subscription.
+func (db *DB) SubscribedCalendarID(ctx context.Context, accountID string) (string, error) {
+	var id string
+	err := db.QueryRowContext(ctx,
+		`SELECT id FROM calendars WHERE account_id = ? LIMIT 1`, accountID).Scan(&id)
+	if errors.Is(err, sql.ErrNoRows) {
+		return "", ErrNotFound
+	}
+	return id, err
+}

internal/store/calendars_test.go

@@ -0,0 +1,358 @@
+package store
+
+import (
+	"context"
+	"strings"
+	"testing"
+	"time"
+)
+
+func connectedAccount(t *testing.T, db *DB, userID string) *CalendarAccount {
+	t.Helper()
+	a := &CalendarAccount{
+		UserID: userID, Provider: "google", Account: "[email protected]",
+		RefreshToken: "1//0-a-real-looking-refresh-token", AccessToken: "ya29.access",
+		ExpiresAt: time.Now().Add(time.Hour),
+	}
+	if err := db.SaveCalendarAccount(context.Background(), a); err != nil {
+		t.Fatal(err)
+	}
+	return a
+}
+
+// The same claim the mailbox tokens have to meet: what is written must not be
+// readable in the file a backup copies.
+func TestCalendarTokensAreNotStoredInTheClear(t *testing.T) {
+	db, userID := sealedStore(t)
+	ctx := context.Background()
+	a := connectedAccount(t, db, userID)
+
+	var refresh, access string
+	if err := db.QueryRowContext(ctx,
+		`SELECT refresh_token, access_token FROM calendar_accounts WHERE id = ?`,
+		a.ID).Scan(&refresh, &access); err != nil {
+		t.Fatal(err)
+	}
+	if strings.Contains(refresh, "real-looking") || strings.Contains(access, "ya29") {
+		t.Fatalf("a token is in the row as written: %q %q", refresh, access)
+	}
+	// The address stays readable, which is the reason for sealing named columns
+	// rather than the whole row.
+	var account string
+	if err := db.QueryRowContext(ctx,
+		`SELECT account FROM calendar_accounts WHERE id = ?`, a.ID).Scan(&account); err != nil {
+		t.Fatal(err)
+	}
+	if account != "[email protected]" {
+		t.Errorf("the address was sealed too: %q", account)
+	}
+
+	back, err := db.CalendarAccountFor(ctx, userID, "google")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if back.RefreshToken != a.RefreshToken || back.AccessToken != a.AccessToken {
+		t.Errorf("the tokens did not survive the round trip: %+v", back)
+	}
+}
+
+// Connecting again must replace what was there, not fail. It is the same OAuth
+// flow run a second time, and the person's word for it is "connect", not "add".
+func TestConnectingAgainReplacesTheAccount(t *testing.T) {
+	db, userID := sealedStore(t)
+	ctx := context.Background()
+	first := connectedAccount(t, db, userID)
+
+	second := &CalendarAccount{
+		UserID: userID, Provider: "google", Account: "[email protected]",
+		RefreshToken: "1//0-fresh", AccessToken: "ya29.fresh",
+	}
+	if err := db.SaveCalendarAccount(ctx, second); err != nil {
+		t.Fatalf("connecting a second time failed: %v", err)
+	}
+	// And the id in hand is the row that is actually there. The calendars hang off
+	// it, so an id nothing points at would attach them to nothing.
+	if second.ID != first.ID {
+		t.Errorf("the second connect came back with id %q, want the existing %q",
+			second.ID, first.ID)
+	}
+
+	back, err := db.CalendarAccountFor(ctx, userID, "google")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if back.RefreshToken != "1//0-fresh" {
+		t.Errorf("the token came back as %q", back.RefreshToken)
+	}
+}
+
+// Google says which calendars exist; only verdande knows which ones somebody wants
+// to look at. A refresh that came back with the same list must not undo the choice.
+func TestRefreshingTheListKeepsWhatWasChosen(t *testing.T) {
+	db, userID := sealedStore(t)
+	ctx := context.Background()
+	a := connectedAccount(t, db, userID)
+
+	list := []Calendar{
+		{RemoteID: "primary", Name: "[email protected]", Colour: "#3f51b5", Primary: true},
+		{RemoteID: "fam", Name: "Familien", Colour: "#0b8043"},
+		{RemoteID: "old", Name: "Et delt"},
+	}
+	if err := db.ReplaceCalendars(ctx, a.ID, list); err != nil {
+		t.Fatal(err)
+	}
+
+	// Nothing is shown to begin with: an account with a dozen shared calendars in
+	// it should not fill somebody's grid the moment they connect it.
+	stored, err := db.Calendars(ctx, a.ID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(stored) != 3 {
+		t.Fatalf("got %d calendars, want 3", len(stored))
+	}
+	for _, c := range stored {
+		if c.Shown {
+			t.Errorf("%q was shown without anybody asking for it", c.Name)
+		}
+	}
+
+	var famID string
+	for _, c := range stored {
+		if c.RemoteID == "fam" {
+			famID = c.ID
+		}
+	}
+	if err := db.ShowCalendars(ctx, a.ID, []string{famID}); err != nil {
+		t.Fatal(err)
+	}
+
+	// The sweep runs again, and one calendar has been renamed and one has gone.
+	if err := db.ReplaceCalendars(ctx, a.ID, []Calendar{
+		{RemoteID: "primary", Name: "[email protected]", Colour: "#3f51b5", Primary: true},
+		{RemoteID: "fam", Name: "Familien og hunden", Colour: "#0b8043"},
+	}); err != nil {
+		t.Fatal(err)
+	}
+
+	stored, err = db.Calendars(ctx, a.ID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(stored) != 2 {
+		t.Fatalf("got %d calendars; one that has left the account should stop being drawn",
+			len(stored))
+	}
+	for _, c := range stored {
+		switch c.RemoteID {
+		case "fam":
+			if !c.Shown {
+				t.Error("the choice was undone by a refresh of the list")
+			}
+			if c.Name != "Familien og hunden" {
+				t.Errorf("the new name did not arrive: %q", c.Name)
+			}
+			if c.ID != famID {
+				t.Error("the row was rebuilt rather than updated; its id is what was chosen")
+			}
+		case "primary":
+			if c.Shown {
+				t.Error("a calendar nobody chose became shown")
+			}
+		}
+	}
+}
+
+// A window is replaced, not merged. An event moved out of it has to disappear
+// because it is absent from the answer — and the months on either side must not go
+// with it.
+func TestReplacingAWindowLeavesTheMonthsAroundItAlone(t *testing.T) {
+	db, userID := sealedStore(t)
+	ctx := context.Background()
+	a := connectedAccount(t, db, userID)
+
+	if err := db.ReplaceCalendars(ctx, a.ID, []Calendar{{RemoteID: "primary", Name: "Min"}}); err != nil {
+		t.Fatal(err)
+	}
+	stored, _ := db.Calendars(ctx, a.ID)
+	cal := stored[0]
+	if err := db.ShowCalendars(ctx, a.ID, []string{cal.ID}); err != nil {
+		t.Fatal(err)
+	}
+
+	july := CalendarEvent{RemoteID: "j", Summary: "Juli", StartDay: "2026-07-15", EndDay: "2026-07-15"}
+	august := CalendarEvent{RemoteID: "a", Summary: "August", StartDay: "2026-08-15", EndDay: "2026-08-15"}
+	if err := db.ReplaceCalendarEvents(ctx, cal.ID, "2026-07-01", "2026-07-31",
+		[]CalendarEvent{july}); err != nil {
+		t.Fatal(err)
+	}
+	if err := db.ReplaceCalendarEvents(ctx, cal.ID, "2026-08-01", "2026-08-31",
+		[]CalendarEvent{august}); err != nil {
+		t.Fatal(err)
+	}
+
+	got, err := db.CalendarEvents(ctx, userID, "2026-07-01", "2026-08-31")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(got) != 2 {
+		t.Fatalf("got %d events, want both months: %+v", len(got), got)
+	}
+
+	// August is synced again and the meeting has been cancelled. July stays.
+	if err := db.ReplaceCalendarEvents(ctx, cal.ID, "2026-08-01", "2026-08-31", nil); err != nil {
+		t.Fatal(err)
+	}
+	got, err = db.CalendarEvents(ctx, userID, "2026-07-01", "2026-08-31")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(got) != 1 || got[0].Summary != "Juli" {
+		t.Fatalf("got %+v; syncing August threw away July", got)
+	}
+}
+
+// The grid asks "which cells does this cover", so an event that straddles the edge
+// of the question has to come back.
+func TestAnEventThatStraddlesTheWindowIsFound(t *testing.T) {
+	db, userID := sealedStore(t)
+	ctx := context.Background()
+	a := connectedAccount(t, db, userID)
+	if err := db.ReplaceCalendars(ctx, a.ID, []Calendar{{RemoteID: "c", Name: "Min", Colour: "#0b8043"}}); err != nil {
+		t.Fatal(err)
+	}
+	stored, _ := db.Calendars(ctx, a.ID)
+	if err := db.ShowCalendars(ctx, a.ID, []string{stored[0].ID}); err != nil {
+		t.Fatal(err)
+	}
+	if err := db.ReplaceCalendarEvents(ctx, stored[0].ID, "2026-08-01", "2026-09-30",
+		[]CalendarEvent{
+			{RemoteID: "trip", Summary: "Aarhus", StartDay: "2026-08-28", EndDay: "2026-09-02", AllDay: true},
+		}); err != nil {
+		t.Fatal(err)
+	}
+
+	// A week that contains neither end of it.
+	got, err := db.CalendarEvents(ctx, userID, "2026-08-31", "2026-09-01")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(got) != 1 {
+		t.Fatalf("got %+v; an event covering the whole week was not found", got)
+	}
+	// The calendar's own colour rides along, or the chip has to ask for it per row.
+	if got[0].Colour != "#0b8043" || got[0].CalendarName != "Min" {
+		t.Errorf("the calendar did not come with the event: %+v", got[0])
+	}
+}
+
+// Somebody else's calendar is somebody else's.
+func TestOnlyTheOwnersEventsComeBack(t *testing.T) {
+	db, userID := sealedStore(t)
+	ctx := context.Background()
+
+	other := &User{Email: "[email protected]", Name: "Andreas"}
+	if err := db.CreateUser(ctx, other, "Indbakke"); err != nil {
+		t.Fatal(err)
+	}
+	theirs := &CalendarAccount{UserID: other.ID, Provider: "google", RefreshToken: "r"}
+	if err := db.SaveCalendarAccount(ctx, theirs); err != nil {
+		t.Fatal(err)
+	}
+	if err := db.ReplaceCalendars(ctx, theirs.ID, []Calendar{{RemoteID: "c", Name: "Deres"}}); err != nil {
+		t.Fatal(err)
+	}
+	stored, _ := db.Calendars(ctx, theirs.ID)
+	if err := db.ShowCalendars(ctx, theirs.ID, []string{stored[0].ID}); err != nil {
+		t.Fatal(err)
+	}
+	if err := db.ReplaceCalendarEvents(ctx, stored[0].ID, "2026-08-01", "2026-08-31",
+		[]CalendarEvent{{RemoteID: "x", Summary: "Privat", StartDay: "2026-08-10", EndDay: "2026-08-10"}}); err != nil {
+		t.Fatal(err)
+	}
+
+	got, err := db.CalendarEvents(ctx, userID, "2026-08-01", "2026-08-31")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(got) != 0 {
+		t.Fatalf("somebody else's calendar came back: %+v", got)
+	}
+}
+
+// A calendar turned off stops being drawn, and stops costing the grid anything.
+func TestTurningACalendarOffRemovesItsEvents(t *testing.T) {
+	db, userID := sealedStore(t)
+	ctx := context.Background()
+	a := connectedAccount(t, db, userID)
+	if err := db.ReplaceCalendars(ctx, a.ID, []Calendar{{RemoteID: "c", Name: "Min"}}); err != nil {
+		t.Fatal(err)
+	}
+	stored, _ := db.Calendars(ctx, a.ID)
+	if err := db.ShowCalendars(ctx, a.ID, []string{stored[0].ID}); err != nil {
+		t.Fatal(err)
+	}
+	if err := db.ReplaceCalendarEvents(ctx, stored[0].ID, "2026-08-01", "2026-08-31",
+		[]CalendarEvent{{RemoteID: "x", Summary: "Møde", StartDay: "2026-08-10", EndDay: "2026-08-10"}}); err != nil {
+		t.Fatal(err)
+	}
+
+	if err := db.ShowCalendars(ctx, a.ID, nil); err != nil {
+		t.Fatal(err)
+	}
+	var count int
+	if err := db.QueryRowContext(ctx, `SELECT count(*) FROM calendar_events`).Scan(&count); err != nil {
+		t.Fatal(err)
+	}
+	if count != 0 {
+		t.Errorf("%d events of a calendar nobody is looking at are still in the table", count)
+	}
+}
+
+// Disconnecting takes the calendars and the events with it. Unlike the tasks a
+// mailbox made, none of this is the person's own work — it is a copy of somebody
+// else's calendar and it means nothing without the account.
+func TestDisconnectingTakesEverythingWithIt(t *testing.T) {
+	db, userID := sealedStore(t)
+	ctx := context.Background()
+	a := connectedAccount(t, db, userID)
+	if err := db.ReplaceCalendars(ctx, a.ID, []Calendar{{RemoteID: "c", Name: "Min"}}); err != nil {
+		t.Fatal(err)
+	}
+	stored, _ := db.Calendars(ctx, a.ID)
+	if err := db.ShowCalendars(ctx, a.ID, []string{stored[0].ID}); err != nil {
+		t.Fatal(err)
+	}
+	if err := db.ReplaceCalendarEvents(ctx, stored[0].ID, "2026-08-01", "2026-08-31",
+		[]CalendarEvent{{RemoteID: "x", Summary: "Møde", StartDay: "2026-08-10", EndDay: "2026-08-10"}}); err != nil {
+		t.Fatal(err)
+	}
+
+	if err := db.DeleteCalendarAccount(ctx, userID, a.ID); err != nil {
+		t.Fatal(err)
+	}
+	for _, table := range []string{"calendar_accounts", "calendars", "calendar_events"} {
+		var count int
+		if err := db.QueryRowContext(ctx, `SELECT count(*) FROM `+table).Scan(&count); err != nil {
+			t.Fatal(err)
+		}
+		if count != 0 {
+			t.Errorf("%s still holds %d rows after disconnecting", table, count)
+		}
+	}
+}
+
+// The sweep finds people by the presence of an account, so it has to keep working
+// now that the credential in it is ciphertext.
+func TestTheSweepFindsAConnectedCalendar(t *testing.T) {
+	db, userID := sealedStore(t)
+	connectedAccount(t, db, userID)
+
+	users, err := db.UsersWithCalendars(context.Background())
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(users) != 1 || users[0] != userID {
+		t.Fatalf("the sweep found %v", users)
+	}
+}

internal/store/comments.go

@@ -27,6 +27,7 @@ type Attachment struct {
 	// GroupID hangs the file on a project group rather than on any one task in
 	// it: the contract that governs all of "Arbejde", not a step in it.
 	GroupID    string
+	NoteID     string
 	Filename   string
 	MimeType   string
 	Size       int64
@@ -157,17 +158,18 @@ func (db *DB) CreateAttachment(ctx context.Context, a *Attachment) error {
 	a.CreatedAt = time.Now().UTC()
 
 	_, err := db.ExecContext(ctx,
-		`INSERT INTO attachments (id, task_id, comment_id, group_id, filename, mime_type,
+		`INSERT INTO attachments (id, task_id, comment_id, group_id, note_id, filename, mime_type,
 		                          size, path, uploaded_by, created_at)
-		 VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?)`,
+		 VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)`,
 		a.ID, nullString(a.TaskID), nullString(a.CommentID), nullString(a.GroupID),
+		nullString(a.NoteID),
 		a.Filename, a.MimeType, a.Size, a.Path, a.UploadedBy, a.CreatedAt.Unix())
 	return err
 }
 
 func (db *DB) ListTaskAttachments(ctx context.Context, taskID string) ([]Attachment, error) {
 	rows, err := db.QueryContext(ctx,
-		`SELECT id, task_id, comment_id, group_id, filename, mime_type, size, path, uploaded_by, created_at
+		`SELECT id, task_id, comment_id, group_id, note_id, filename, mime_type, size, path, uploaded_by, created_at
 		 FROM attachments WHERE task_id = ? ORDER BY created_at`, taskID)
 	if err != nil {
 		return nil, err
@@ -176,11 +178,24 @@ func (db *DB) ListTaskAttachments(ctx context.Context, taskID string) ([]Attachm
 	return scanAttachments(rows)
 }
 
+// ListNoteAttachments is the files inside one note — the pictures and scans that
+// came with it, and anything added since.
+func (db *DB) ListNoteAttachments(ctx context.Context, noteID string) ([]Attachment, error) {
+	rows, err := db.QueryContext(ctx,
+		`SELECT id, task_id, comment_id, group_id, note_id, filename, mime_type, size, path, uploaded_by, created_at
+		 FROM attachments WHERE note_id = ? ORDER BY created_at`, noteID)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	return scanAttachments(rows)
+}
+
 // ListGroupAttachments is the documents that belong to a whole group rather than
 // to anything inside it.
 func (db *DB) ListGroupAttachments(ctx context.Context, groupID string) ([]Attachment, error) {
 	rows, err := db.QueryContext(ctx,
-		`SELECT id, task_id, comment_id, group_id, filename, mime_type, size, path, uploaded_by, created_at
+		`SELECT id, task_id, comment_id, group_id, note_id, filename, mime_type, size, path, uploaded_by, created_at
 		 FROM attachments WHERE group_id = ? ORDER BY created_at`, groupID)
 	if err != nil {
 		return nil, err
@@ -195,7 +210,7 @@ func (db *DB) attachmentsByComment(ctx context.Context, commentIDs []string) (ma
 		args[i] = id
 	}
 	rows, err := db.QueryContext(ctx,
-		`SELECT id, task_id, comment_id, group_id, filename, mime_type, size, path, uploaded_by, created_at
+		`SELECT id, task_id, comment_id, group_id, note_id, filename, mime_type, size, path, uploaded_by, created_at
 		 FROM attachments WHERE comment_id IN (`+placeholders(len(commentIDs))+`)
 		 ORDER BY created_at`, args...)
 	if err != nil {
@@ -218,15 +233,16 @@ func scanAttachments(rows *sql.Rows) ([]Attachment, error) {
 	out := []Attachment{}
 	for rows.Next() {
 		var a Attachment
-		var taskID, commentID, groupID sql.NullString
+		var taskID, commentID, groupID, noteID sql.NullString
 		var created int64
-		if err := rows.Scan(&a.ID, &taskID, &commentID, &groupID, &a.Filename, &a.MimeType,
+		if err := rows.Scan(&a.ID, &taskID, &commentID, &groupID, &noteID, &a.Filename, &a.MimeType,
 			&a.Size, &a.Path, &a.UploadedBy, &created); err != nil {
 			return nil, err
 		}
 		a.TaskID = taskID.String
 		a.CommentID = commentID.String
 		a.GroupID = groupID.String
+		a.NoteID = noteID.String
 		a.CreatedAt = time.Unix(created, 0).UTC()
 		out = append(out, a)
 	}
@@ -235,7 +251,7 @@ func scanAttachments(rows *sql.Rows) ([]Attachment, error) {
 
 func (db *DB) GetAttachment(ctx context.Context, attachmentID string) (*Attachment, error) {
 	rows, err := db.QueryContext(ctx,
-		`SELECT id, task_id, comment_id, group_id, filename, mime_type, size, path, uploaded_by, created_at
+		`SELECT id, task_id, comment_id, group_id, note_id, filename, mime_type, size, path, uploaded_by, created_at
 		 FROM attachments WHERE id = ?`, attachmentID)
 	if err != nil {
 		return nil, err

internal/store/mailboxes_test.go

@@ -195,10 +195,14 @@ func TestAGmailConnectedBeforeTheMoveSurvivesIt(t *testing.T) {
 	}
 	values := `{"refresh_token":"` + sealed + `","trigger":"label","label":"Verdande",` +
 		`"email":"[email protected]","seen":["abc","def"],"project_id":"p-1"}`
+	// The conflict target is (user_id, scope) since 0025 — before that the table
+	// held one row per person and the upsert renamed its scope, which is the bug
+	// 0025 exists to undo. Nothing conflicts here; the clause only has to be legal
+	// against the schema this test is running on.
 	if _, err := db.ExecContext(context.Background(), `
 		INSERT INTO user_settings (user_id, scope, values_json, updated_at)
 		VALUES (?, 'gmail', ?, 0)
-		ON CONFLICT (user_id) DO UPDATE SET scope = 'gmail', values_json = excluded.values_json`,
+		ON CONFLICT (user_id, scope) DO UPDATE SET values_json = excluded.values_json`,
 		userID, values); err != nil {
 		t.Fatal(err)
 	}

internal/store/migrations/0019_nav_order.sql

@@ -0,0 +1,13 @@
+-- The order of the fixed views in the sidebar.
+--
+-- On the account rather than in the browser, and for the reason the sidebar's
+-- width is the other way round: a width is a fact about the screen you are at, and
+-- the answer on a phone is not the answer on a monitor. Which order you want I dag,
+-- Kommende, Venter and Indbakken in is a fact about you, and it should be the same
+-- on the laptop as on the phone.
+--
+-- A list of keys rather than a number per row, for the same reason sidebar_collapsed
+-- is: the set of views changes with the program, and a key that no longer exists
+-- costs nothing — the sidebar draws what it recognises and appends anything new at
+-- the end. That is what makes adding a view later not a migration.
+ALTER TABLE users ADD COLUMN nav_order TEXT NOT NULL DEFAULT '[]';

internal/store/migrations/0020_fold_note_tags.sql

@@ -0,0 +1,29 @@
+-- #garageristeriet and #GarageRisteriet are the same project.
+--
+-- They were not, because the key was stored exactly as typed and looked up the
+-- same way — so a note that named a project in lower case simply did not appear
+-- on it, silently and with nothing to suggest why.
+--
+-- Folded on the way in from now on; this brings the rows already written into
+-- line. Only projects: a [[note title]] is a title, and two notes called "Møde"
+-- and "møde" are two notes.
+--
+-- The primary key is (note_id, kind, target_id), so folding can collide with a row
+-- that is already there — a note that wrote both spellings. INSERT OR IGNORE into
+-- a fresh set and swap, which keeps one of each rather than failing on the pair.
+CREATE TABLE note_links_folded (
+    note_id     TEXT NOT NULL REFERENCES notes (id) ON DELETE CASCADE,
+    kind        TEXT NOT NULL CHECK (kind IN ('task', 'note', 'project')),
+    target_id   TEXT NOT NULL,
+    PRIMARY KEY (note_id, kind, target_id)
+);
+
+INSERT OR IGNORE INTO note_links_folded (note_id, kind, target_id)
+SELECT note_id, kind,
+       CASE WHEN kind = 'project' THEN lower(target_id) ELSE target_id END
+FROM note_links;
+
+DROP TABLE note_links;
+ALTER TABLE note_links_folded RENAME TO note_links;
+
+CREATE INDEX note_links_backwards ON note_links (kind, target_id);

internal/store/migrations/0021_note_attachments.sql

@@ -0,0 +1,45 @@
+-- A note can carry files, the way a task and a group already can.
+--
+-- Apple Notes is full of photographs, scans and pasted screenshots, and a note
+-- that arrives here as words alone is not that note — it is a summary of it. The
+-- import writes the files as attachments and rewrites the links in the text, so a
+-- picture that was in the middle of a paragraph is still in the middle of it.
+--
+-- Same table as everything else attaches to, rather than one of its own. The files
+-- are content-addressed and deduplicated on disk, the upload path is written and
+-- tested, and the cleanup that removes an orphan already walks this table. A
+-- second table would be a second everything.
+
+-- verdande:rebuild-tables
+
+CREATE TABLE attachments_with_notes (
+    id          TEXT PRIMARY KEY,
+    task_id     TEXT REFERENCES tasks (id) ON DELETE CASCADE,
+    comment_id  TEXT REFERENCES comments (id) ON DELETE CASCADE,
+    group_id    TEXT REFERENCES project_groups (id) ON DELETE CASCADE,
+    note_id     TEXT REFERENCES notes (id) ON DELETE CASCADE,
+    filename    TEXT NOT NULL,
+    mime_type   TEXT NOT NULL DEFAULT 'application/octet-stream',
+    size        INTEGER NOT NULL,
+    path        TEXT NOT NULL,
+    uploaded_by TEXT NOT NULL REFERENCES users (id) ON DELETE CASCADE,
+    created_at  INTEGER NOT NULL,
+    -- Counted, not spelled out as pairs: with four columns the pairwise version is
+    -- six clauses, and the one that is wrong looks exactly like the one that is right.
+    CHECK ((task_id IS NOT NULL) + (comment_id IS NOT NULL)
+         + (group_id IS NOT NULL) + (note_id IS NOT NULL) = 1)
+);
+
+INSERT INTO attachments_with_notes
+    (id, task_id, comment_id, group_id, filename, mime_type, size, path, uploaded_by, created_at)
+SELECT id, task_id, comment_id, group_id, filename, mime_type, size, path, uploaded_by, created_at
+FROM attachments;
+
+DROP TABLE attachments;
+
+ALTER TABLE attachments_with_notes RENAME TO attachments;
+
+CREATE INDEX idx_attachments_task ON attachments (task_id) WHERE task_id IS NOT NULL;
+CREATE INDEX idx_attachments_comment ON attachments (comment_id) WHERE comment_id IS NOT NULL;
+CREATE INDEX idx_attachments_group ON attachments (group_id) WHERE group_id IS NOT NULL;
+CREATE INDEX idx_attachments_note ON attachments (note_id) WHERE note_id IS NOT NULL;

internal/store/migrations/0022_beacon.sql

@@ -0,0 +1,26 @@
+-- One row per installation that has ever reported in.
+--
+-- This table only exists on the instance that is acting as the collector. Every
+-- other instance has it too, empty, because the schema is the same everywhere —
+-- and because "am I the collector" is a setting, not a build.
+--
+-- What is deliberately NOT here is the point of the whole feature: there is no
+-- column for an IP address, a hostname, a domain, an account, a count of tasks,
+-- or anything else. The two things stored are the two things sent, and the table
+-- is the promise written down where it cannot drift from the prose — a column
+-- added here later is a promise broken, and it should be as awkward to add as
+-- possible.
+--
+-- `instance_id` is the primary key rather than a rowid alias, because the same
+-- installation reporting daily must update its row rather than grow a new one.
+-- What is wanted is "how many installations", not "how many pings".
+CREATE TABLE beacon_installs (
+    instance_id TEXT PRIMARY KEY,
+    version     TEXT NOT NULL DEFAULT '',
+    first_seen  INTEGER NOT NULL,
+    last_seen   INTEGER NOT NULL
+);
+
+-- The count is always "seen in the last N days", so last_seen is what every query
+-- sorts and filters on.
+CREATE INDEX beacon_by_last_seen ON beacon_installs (last_seen DESC);

internal/store/migrations/0023_calendars.sql

@@ -0,0 +1,111 @@
+-- Calendars read from somewhere else: the account, the calendars in it, and the
+-- events they hold.
+--
+-- Not in `mailboxes`, and it was the first thing considered. The two look alike
+-- from a distance — a person connects a Google account over OAuth, tokens are
+-- sealed, a sweep polls it — and every column past that disagrees. `trigger_kind`,
+-- `seen`, `last_uid` and `project_id` all answer "what turns a message into a
+-- task", and nothing here turns into a task. What is here instead is a *set*:
+-- one account holds many calendars, and a person picks which of them to look at.
+-- `mailboxes` has no room for a one-to-many, and giving it one would push the
+-- other kind's columns onto rows that can never use them.
+--
+-- The decisive part is smaller and more practical. `mailboxes.kind` carries
+-- `CHECK (kind IN ('gmail', 'imap'))`, and SQLite cannot alter a CHECK — adding a
+-- third value means rebuilding the table with foreign keys off, which is the
+-- expensive, careful thing migration 0021 had to do for a reason. Paying that to
+-- store something that shares no column with the table is the wrong trade.
+--
+-- Hence no CHECK on `provider` here. CalDAV is the next source to read, and it
+-- should cost a row, not a rebuild.
+
+-- One connected account per person per provider. The tokens live here rather than
+-- on each calendar: a refresh token copied onto ten rows is ten copies of one
+-- secret, ten refreshes racing each other, and ten places to miss when access is
+-- revoked.
+--
+-- `refresh_token` and `access_token` are written sealed; see internal/secret. The
+-- store's own seal/unseal only covers the settings tables, so this table's methods
+-- call them by hand — the same fact worth knowing that migration 0014 wrote down.
+CREATE TABLE calendar_accounts (
+    id            TEXT PRIMARY KEY,
+    user_id       TEXT NOT NULL REFERENCES users (id) ON DELETE CASCADE,
+    provider      TEXT NOT NULL DEFAULT 'google',
+    -- The address the account reports, so the settings page can say which one is
+    -- connected rather than only that one is.
+    account       TEXT NOT NULL DEFAULT '',
+
+    refresh_token TEXT NOT NULL DEFAULT '',
+    access_token  TEXT NOT NULL DEFAULT '',
+    expires_at    INTEGER NOT NULL DEFAULT 0,
+
+    last_sync_at  INTEGER NOT NULL DEFAULT 0,
+    created_at    INTEGER NOT NULL
+);
+
+-- Connecting again replaces what was there, the way Gmail's does: the OAuth flow
+-- is one account at a time, so a second row for the same provider would be a
+-- second set of tokens for the same grant and no way to say which is live.
+CREATE UNIQUE INDEX calendar_accounts_once ON calendar_accounts (user_id, provider);
+
+-- One row per calendar the account can see, kept whether or not it is shown.
+--
+-- `shown` rather than deleting the ones that are not: a person who turns a calendar
+-- off and on again should get the same row back, and the list is refreshed from
+-- Google on every sync — so a calendar that only existed while it was ticked would
+-- lose its choice every time somebody added a new one.
+--
+-- `colour` is Google's own hex for the calendar. Not one of verdande's ten named
+-- colours, which is the rule everywhere else in this database: those are names so
+-- the interface can restyle them per theme, and they are *verdande's* palette. A
+-- Google calendar is told apart by the colour the person already knows it by, and
+-- that colour belongs to Google.
+CREATE TABLE calendars (
+    id         TEXT PRIMARY KEY,
+    account_id TEXT NOT NULL REFERENCES calendar_accounts (id) ON DELETE CASCADE,
+    -- The id Google knows it by. Long, and an address for the primary calendar.
+    remote_id  TEXT NOT NULL,
+    name       TEXT NOT NULL DEFAULT '',
+    colour     TEXT NOT NULL DEFAULT '',
+    time_zone  TEXT NOT NULL DEFAULT '',
+    primary_one INTEGER NOT NULL DEFAULT 0,
+    writable   INTEGER NOT NULL DEFAULT 0,
+    shown      INTEGER NOT NULL DEFAULT 0,
+    sort_order INTEGER NOT NULL DEFAULT 0
+);
+
+CREATE UNIQUE INDEX calendars_once ON calendars (account_id, remote_id);
+
+-- The events themselves, cached.
+--
+-- Cached rather than fetched per view, and the reason is what a month grid does:
+-- it pages. Asking Google on every arrow press means a token refresh, a round trip
+-- and a spinner for a question that was answered ninety seconds ago — and a
+-- calendar that is slower than the calendar it is showing is not worth having.
+-- The window is refreshed by the sweep and by the "fetch now" button.
+--
+-- Days rather than instants, and both ends inclusive. A grid asks one question —
+-- "which cells does this cover" — and `start_day <= ? AND end_day >= ?` is that
+-- question. `starts_at` is kept as Google wrote it, offset and all, because it is
+-- what the chip shows and reparsing it here would ask *this process* what time
+-- zone it is in. An all-day event has neither: it has a day, not a moment, and
+-- inventing midnight for it is how an event moves a day when a container moves
+-- time zone.
+CREATE TABLE calendar_events (
+    id          TEXT PRIMARY KEY,
+    calendar_id TEXT NOT NULL REFERENCES calendars (id) ON DELETE CASCADE,
+    remote_id   TEXT NOT NULL,
+    summary     TEXT NOT NULL DEFAULT '',
+    starts_at   TEXT NOT NULL DEFAULT '',
+    ends_at     TEXT NOT NULL DEFAULT '',
+    start_day   TEXT NOT NULL,
+    end_day     TEXT NOT NULL,
+    all_day     INTEGER NOT NULL DEFAULT 0,
+    location    TEXT NOT NULL DEFAULT '',
+    url         TEXT NOT NULL DEFAULT ''
+);
+
+-- The one query there is: everything a person can see, between two days. Ordered
+-- by the account so the join has somewhere to start, then by the days the grid
+-- compares against.
+CREATE INDEX calendar_events_by_day ON calendar_events (calendar_id, start_day, end_day);

internal/store/migrations/0024_note_archive.sql

@@ -0,0 +1,23 @@
+-- A note can be put away without being thrown away.
+--
+-- The trash already exists and is the wrong tool. It says "this was a mistake,
+-- and in thirty days it is gone" — so anything worth keeping cannot go in it, and
+-- an archive of twelve hundred imported notes is exactly the case where most of
+-- them are worth keeping and almost none are worth looking at. Without somewhere
+-- to put them, the list is the whole archive forever, and finding this week's note
+-- means reading past a decade.
+--
+-- A column rather than a folder. Verdande already refused a second hierarchy for
+-- notes — see 0018 — and archiving is not filing: it is one bit about whether a
+-- note is current, and it has to be answerable next to `deleted_at`, which is the
+-- other bit of the same kind.
+--
+-- Nullable timestamp rather than a boolean, for the same reason `deleted_at` is
+-- one: "when was this put away" answers questions a flag cannot, and it costs the
+-- same byte.
+ALTER TABLE notes ADD COLUMN archived_at INTEGER;
+
+-- The list asks "not deleted, not archived, newest first" on every load, and with
+-- twelve hundred notes that is the query that has to be quick.
+CREATE INDEX notes_current ON notes (archived_at, deleted_at, updated_at DESC)
+    WHERE deleted_at IS NULL;

internal/store/migrations/0025_user_settings_per_scope.sql

@@ -0,0 +1,37 @@
+-- One row per person *and scope*, which is what the table always meant.
+--
+-- `user_settings` was created with `user_id` as its whole primary key, and its
+-- upsert rewrote `scope` on conflict. So a person had exactly one settings row,
+-- and whichever scope was written last was the only one that survived: saving an
+-- AI provider deleted the Gmail connection, and connecting a calendar deleted the
+-- AI provider. Nothing reported it — the write succeeded, and the loss was in the
+-- row it landed on.
+--
+-- This was seen coming twice. Migration 0011 gave the instance's settings their
+-- own table partly for this reason and wrote the warning down in as many words;
+-- 0014 moved mailboxes out and said the warning "was nearly walked into a second
+-- time". The third time was the calendar, which added a `calendar` scope beside
+-- `ai` and `gmail` — and walked in.
+--
+-- The lesson worth keeping: a warning in a migration is read by whoever is editing
+-- *that* migration, and nobody was. The shape is fixed here so there is nothing
+-- left to warn about.
+--
+-- SQLite cannot change a primary key in place, so the table is rebuilt. Existing
+-- rows are copied as they are: each person has at most one, and it holds whatever
+-- scope won last. What the earlier writes lost is already gone and cannot be
+-- recovered here — the values were overwritten, not orphaned.
+CREATE TABLE user_settings_new (
+    user_id     TEXT NOT NULL REFERENCES users (id) ON DELETE CASCADE,
+    scope       TEXT NOT NULL DEFAULT 'general',
+    values_json TEXT NOT NULL DEFAULT '{}',
+    updated_at  INTEGER NOT NULL,
+    PRIMARY KEY (user_id, scope)
+);
+
+INSERT INTO user_settings_new (user_id, scope, values_json, updated_at)
+SELECT user_id, scope, values_json, updated_at FROM user_settings;
+
+DROP TABLE user_settings;
+
+ALTER TABLE user_settings_new RENAME TO user_settings;

internal/store/migrations/0026_calendar_subscriptions.sql

@@ -0,0 +1,30 @@
+-- Abonnement på en kalender, man kun har en adresse til.
+--
+-- Google-vejen er OAuth: én konto pr. person, hvor tokenet er identiteten, og
+-- `calendar_accounts_once` sørgede for netop det — én række pr. (person,
+-- udbyder). Et abonnement er en anden slags ting. Der er intet token og ingen
+-- konto, kun en adresse, og man har flere: helligdage, en fodboldklub, en
+-- fælleskalender fra arbejdet. Det er derfor det blev bedt om som "flere
+-- kalendere".
+--
+-- Samme tabel frem for en ny. Et abonnement er én kalender med begivenheder i, og
+-- det er præcis det, `calendars` og `calendar_events` allerede beskriver — med
+-- vinduet, `shown`, farven og hele fejemaskinen omkring sig. En tabel til ville
+-- være en anden vej til det samme sted, og to veje til ét sted er to steder at
+-- rette den dag noget om begivenheder ændrer sig.
+--
+-- Adressen bliver identiteten, som tokenet er det for Google. To rækker med den
+-- samme adresse for den samme person ville være den samme kalender hentet to
+-- gange, og der er ingen måde at sige hvilken der gælder.
+ALTER TABLE calendar_accounts ADD COLUMN url TEXT NOT NULL DEFAULT '';
+
+-- Det gamle indeks holder stadig for OAuth-rækkerne — dem uden adresse — og
+-- slipper abonnementerne fri. Delvise indekser er den ene ting SQLite kan her,
+-- som en tabelombygning ellers skulle til for.
+DROP INDEX calendar_accounts_once;
+
+CREATE UNIQUE INDEX calendar_accounts_once
+    ON calendar_accounts (user_id, provider) WHERE url = '';
+
+CREATE UNIQUE INDEX calendar_subscription_once
+    ON calendar_accounts (user_id, url) WHERE url <> '';

internal/store/notes.go

@@ -10,15 +10,26 @@ import (
 
 // Note is a page of Markdown belonging to a project, or to nobody.
 type Note struct {
-	ID        string     `json:"id"`
-	ProjectID string     `json:"project_id,omitempty"`
-	Title     string     `json:"title"`
-	Body      string     `json:"body"`
-	CreatedBy string     `json:"created_by,omitempty"`
-	Pinned    bool       `json:"pinned"`
-	CreatedAt time.Time  `json:"created_at"`
-	UpdatedAt time.Time  `json:"updated_at"`
-	DeletedAt *time.Time `json:"deleted_at,omitempty"`
+	ID         string     `json:"id"`
+	ProjectID  string     `json:"project_id,omitempty"`
+	Title      string     `json:"title"`
+	Body       string     `json:"body"`
+	CreatedBy  string     `json:"created_by,omitempty"`
+	Pinned     bool       `json:"pinned"`
+	CreatedAt  time.Time  `json:"created_at"`
+	UpdatedAt  time.Time  `json:"updated_at"`
+	DeletedAt  *time.Time `json:"deleted_at,omitempty"`
+	ArchivedAt *time.Time `json:"archived_at,omitempty"`
+
+	// Preview is the first of the body, for a list that shows one line of it.
+	//
+	// It exists so a list of twelve hundred notes does not have to carry twelve
+	// hundred whole notes: the list rendered 845 KB of JSON to show ninety
+	// characters of each. When it is set, Body is deliberately empty — see
+	// handleListNotes. That is not tidiness but a guard: an editor handed a
+	// truncated body would save the truncation, and the note would be cut down to
+	// its own preview.
+	Preview string `json:"preview,omitempty"`
 
 	// Links is what the body points at, read out of the text on the way in. Never
 	// set by a caller: it is derived, and a caller that set it would be describing
@@ -33,7 +44,16 @@ type NoteLink struct {
 }
 
 const noteColumns = `id, project_id, title, body, created_by, pinned,
-	created_at, updated_at, deleted_at`
+	created_at, updated_at, deleted_at, archived_at`
+
+// The same columns, said with the table in front of them.
+//
+// Needed only by the search, which joins `notes_fts` — and that table carries its
+// own `id` and `project_id` (UNINDEXED, so the row can be found from a match).
+// Unqualified, SQLite cannot tell which one is meant and refuses the query.
+const noteColumnsQualified = `notes.id, notes.project_id, notes.title, notes.body,
+	notes.created_by, notes.pinned, notes.created_at, notes.updated_at, notes.deleted_at,
+	notes.archived_at`
 
 // Reference syntax, and deliberately the same characters the quick-add parser
 // already uses. A `#Firma` in a note means the same project as a `#Firma` typed
@@ -62,11 +82,12 @@ func (db *DB) SaveNote(ctx context.Context, n *Note) error {
 	}
 	n.UpdatedAt = now
 
-	// A note with no title takes its first line, the way Apple Notes does. A list
-	// of untitled notes is a list nobody can read.
-	if strings.TrimSpace(n.Title) == "" {
-		n.Title = firstLine(n.Body)
-	}
+	// The title is always the first line, the way Apple Notes does it. Not "when it
+	// is empty": derived once and then left alone, it goes stale the moment somebody
+	// rewrites the opening of a note, and the list ends up calling a note by a name
+	// that is nowhere in it. The column is a cache of the body, not a field beside
+	// it, and every caller gets the same answer because none of them can set it.
+	n.Title = firstLine(n.Body)
 
 	return db.Tx(ctx, func(tx *sql.Tx) error {
 		var projectID any
@@ -127,7 +148,14 @@ func LinksIn(body string) []NoteLink {
 		add("task", strings.ToLower(m[1]))
 	}
 	for _, m := range projectRef.FindAllStringSubmatch(body, -1) {
-		add("project", m[1])
+		// Folded, because #garageristeriet and #GarageRisteriet are the same project
+		// to everybody except a database. The key is stored folded and looked up
+		// folded, so the comparison stays an exact match and keeps using its index —
+		// a comparison that lowered the column instead would read the whole table.
+		//
+		// The project's real spelling is not lost: it is on the project, which is
+		// what the interface shows. This column is a key, not a label.
+		add("project", strings.ToLower(m[1]))
 	}
 	for _, m := range noteRef.FindAllStringSubmatch(body, -1) {
 		add("note", strings.TrimSpace(m[1]))
@@ -176,11 +204,57 @@ func (db *DB) NotesInProject(ctx context.Context, projectID string) ([]Note, err
 		projectID)
 }
 
+// LooseNotes are the ones filed under no project — a person's own, the way a task
+// in the inbox is. Nobody else can see them, so there is no role to ask about.
+func (db *DB) LooseNotes(ctx context.Context, userID string) ([]Note, error) {
+	return db.notesWhere(ctx, `
+		WHERE project_id IS NULL AND created_by = ? AND deleted_at IS NULL
+		ORDER BY pinned DESC, updated_at DESC`, userID)
+}
+
+// AllNotes is everything a person can see: their own loose ones, and the ones in
+// projects they are part of.
+//
+// This is what the Notes page lists. Filing a note in a project is how it gets
+// shared, and a list that dropped it at that moment would make sharing look like
+// deleting — which is exactly how it read before this existed.
+func (db *DB) AllNotes(ctx context.Context, userID string) ([]Note, error) {
+	return db.allNotes(ctx, userID, false)
+}
+
+// ArchivedNotes is the same list, the other way round: what has been put away.
+func (db *DB) ArchivedNotes(ctx context.Context, userID string) ([]Note, error) {
+	return db.allNotes(ctx, userID, true)
+}
+
+func (db *DB) allNotes(ctx context.Context, userID string, archived bool) ([]Note, error) {
+	// Archived notes are left out of the ordinary list rather than mixed in and
+	// greyed: the point of putting something away is not seeing it.
+	state := "notes.archived_at IS NULL"
+	if archived {
+		state = "notes.archived_at IS NOT NULL"
+	}
+	return db.notesJoin(ctx, noteColumnsQualified, `
+		WHERE `+state+` AND deleted_at IS NULL
+		  AND (
+		    (project_id IS NULL AND created_by = ?)
+		    OR project_id IN (
+		      SELECT id FROM projects WHERE owner_id = ? AND deleted_at IS NULL
+		      UNION
+		      SELECT project_id FROM project_members WHERE user_id = ?
+		    )
+		  )
+		ORDER BY pinned DESC, updated_at DESC`, userID, userID, userID)
+}
+
 // NotesLinking answers the backwards question: what points at this thing.
 //
 // The reason note_links exists. Without it this would mean reading every note's
 // prose, and a panel that slow is one nobody leaves open.
 func (db *DB) NotesLinking(ctx context.Context, kind, targetID string) ([]Note, error) {
+	if kind == "project" {
+		targetID = strings.ToLower(targetID)
+	}
 	return db.notesWhere(ctx, `
 		WHERE deleted_at IS NULL
 		  AND id IN (SELECT note_id FROM note_links WHERE kind = ? AND target_id = ?)
@@ -199,13 +273,141 @@ func (db *DB) SearchNotes(ctx context.Context, query string, limit int) ([]Note,
 	if expr == "" {
 		return nil, nil
 	}
-	// By rowid, the way tasks do it: `id` is UNINDEXED in the table, so selecting
-	// on it would work and read the whole index to do it.
-	return db.notesWhere(ctx, `
-		WHERE deleted_at IS NULL
-		  AND rowid IN (SELECT rowid FROM notes_fts WHERE notes_fts MATCH ?)
-		ORDER BY updated_at DESC
+	// Ordered by how well it matched, not by when it was last touched.
+	//
+	// `ORDER BY updated_at DESC` was invisible while there were ten notes and
+	// useless at twelve hundred: every one of them was imported the same evening,
+	// so `updated_at` says nothing, and the limit then cut the list at fifty
+	// arbitrary rows. Searching "Tesla" answered with a note about nginx first and
+	// the note actually called "Tesla Model Y" second — which reads as a search
+	// that does not work, because from where the person is sitting it is one.
+	//
+	// bm25 with the title weighted ten times the body. A word in the title is what
+	// the note is *about*; the same word once in a long body is a mention. `fold`
+	// carries the same text transliterated, so it must weigh the same as the body
+	// or a Danish match would outrank an exact one.
+	//
+	// Joined rather than `rowid IN (…)`: the rank belongs to the match, and a
+	// subquery throws it away.
+	found, err := db.notesJoin(ctx, noteColumnsQualified, `
+		JOIN notes_fts ON notes_fts.rowid = notes.rowid
+		WHERE notes.deleted_at IS NULL
+		  AND notes_fts MATCH ?
+		ORDER BY bm25(notes_fts, 10.0, 1.0, 1.0)
 		LIMIT ?`, expr, limit)
+	if err != nil || len(found) > 0 {
+		return found, err
+	}
+	return db.searchNotesInside(ctx, query, limit)
+}
+
+// searchNotesInside finds a word that lives *inside* another word.
+//
+// An index is built of tokens, and a token is what a tokenizer decided was a
+// word. `gamerule keepInventory true` is three of them, and the middle one is
+// `keepinventory` — so "keep inventory" asks for two words that are nowhere, and
+// gets nothing. Reported as "søgning har ikke det store held", which from where
+// the person is sitting is exactly what it is: the note is right there, and the
+// search says there is nothing.
+//
+// A prefix query gets half of it. `keep*` does match `keepinventory`; `inventory*`
+// cannot, because it is not a prefix of anything — and the two are joined with AND,
+// so the half that works is thrown away by the half that cannot.
+//
+// This is not an exotic case in a notes app. A decade of notes is full of
+// commands, identifiers and file names, and every one of them is several words the
+// index thinks is one: `keepInventory`, `VACUUM INTO`, `apple-notes-til-markdown`.
+//
+// So: the index answers first, and when it has nothing, the text is read. Every
+// term has to appear somewhere in the note, anywhere, in any word.
+//
+// # What it costs, and when to stop doing it this way
+//
+// A LIKE with a leading % cannot use an index; this reads every note. At twelve
+// hundred notes that is four megabytes and a millisecond or two, and it only runs
+// when the fast path already came back empty — which is the search that was about
+// to disappoint somebody. At a hundred thousand notes it would be the wrong shape,
+// and the answer then is an FTS5 `trigram` index, not a bigger scan.
+//
+// It does not rank. bm25 needs a match to rank, and there is no match here — that
+// is the whole situation. The rows are the most recently touched first, and the
+// set is small, because the index already said there was nothing in it.
+func (db *DB) searchNotesInside(ctx context.Context, query string, limit int) ([]Note, error) {
+	terms := SearchTerms(query)
+	if len(terms) == 0 {
+		return nil, nil
+	}
+
+	// `fold` is `title || ' ' || body` with the Danish letters transliterated, so
+	// one column covers the title, the body and "gron" for "grøn" at once. LIKE is
+	// case-insensitive for ASCII in SQLite, which is what makes `keepInventory`
+	// answer to "inventory".
+	//
+	// The needle is safe to interpolate into a pattern because `tokenize` splits on
+	// everything that is not a letter or a digit: a term cannot contain % or _, so
+	// there is no wildcard for somebody to smuggle in. It is still a bound
+	// parameter — that is about SQL, and this is about LIKE.
+	where := "WHERE deleted_at IS NULL"
+	args := make([]any, 0, len(terms)+1)
+	for _, term := range terms {
+		where += " AND fold LIKE ?"
+		args = append(args, "%"+FoldDanish(term)+"%")
+	}
+	args = append(args, limit)
+
+	return db.notesWhere(ctx, where+" ORDER BY updated_at DESC LIMIT ?", args...)
+}
+
+// SetNoteTimes writes the dates a note had somewhere else.
+//
+// Only the import calls this, and it exists because SaveNote is right to refuse:
+// `updated_at` is when this program last wrote the note, and letting any caller
+// set it would make the column mean whatever the last writer felt like. A note
+// brought in from Apple Notes is the one case where the dates are facts from
+// before this database existed — and without them a move of twelve hundred notes
+// is a pile that was all written the same evening, which throws away the order
+// they were written in. That order is half of what an archive is.
+func (db *DB) SetNoteTimes(ctx context.Context, id string, created, updated time.Time) error {
+	if created.IsZero() && updated.IsZero() {
+		return nil
+	}
+	// COALESCE, so a note carrying only one of the two keeps what it already had
+	// for the other rather than being stamped with the zero time — which would sort
+	// it to the year one.
+	var c, u any
+	if !created.IsZero() {
+		c = created.Unix()
+	}
+	if !updated.IsZero() {
+		u = updated.Unix()
+	}
+	_, err := db.ExecContext(ctx, `
+		UPDATE notes
+		   SET created_at = COALESCE(?, created_at),
+		       updated_at = COALESCE(?, updated_at)
+		 WHERE id = ?`, c, u, id)
+	return err
+}
+
+// SetNoteArchived puts a note away, or takes it back out.
+//
+// Separate from DeleteNote because they mean different things and the difference
+// is the whole feature: the trash says "this was a mistake, and in thirty days it
+// is gone", and the archive says "this is finished, and I want to keep it". A
+// twelve-hundred-note import is mostly the second, and without somewhere to put
+// them the list is the whole archive forever.
+//
+// `updated_at` is deliberately not touched. Archiving is not editing, and a list
+// sorted by when things were last written should not be reordered by somebody
+// tidying up.
+func (db *DB) SetNoteArchived(ctx context.Context, id string, archived bool) error {
+	var at any
+	if archived {
+		at = time.Now().Unix()
+	}
+	_, err := db.ExecContext(ctx,
+		`UPDATE notes SET archived_at = ? WHERE id = ? AND deleted_at IS NULL`, at, id)
+	return err
 }
 
 // DeleteNote puts it in the trash. Nothing here removes a row.
@@ -225,7 +427,13 @@ func (db *DB) RestoreNote(ctx context.Context, id string) error {
 }
 
 func (db *DB) notesWhere(ctx context.Context, where string, args ...any) ([]Note, error) {
-	rows, err := db.QueryContext(ctx, `SELECT `+noteColumns+` FROM notes `+where, args...)
+	return db.notesJoin(ctx, noteColumns, where, args...)
+}
+
+// notesJoin is notesWhere with the column list spelled out, for the one caller
+// that joins another table and must therefore say which `id` it means.
+func (db *DB) notesJoin(ctx context.Context, columns, where string, args ...any) ([]Note, error) {
+	rows, err := db.QueryContext(ctx, `SELECT `+columns+` FROM notes `+where, args...)
 	if err != nil {
 		return nil, err
 	}
@@ -265,10 +473,10 @@ func scanNote(row scanner) (Note, error) {
 	var n Note
 	var projectID, createdBy sql.NullString
 	var created, updated int64
-	var deleted sql.NullInt64
+	var deleted, archived sql.NullInt64
 
 	if err := row.Scan(&n.ID, &projectID, &n.Title, &n.Body, &createdBy,
-		&n.Pinned, &created, &updated, &deleted); err != nil {
+		&n.Pinned, &created, &updated, &deleted, &archived); err != nil {
 		return n, err
 	}
 	n.ProjectID = projectID.String
@@ -279,5 +487,9 @@ func scanNote(row scanner) (Note, error) {
 		t := time.Unix(deleted.Int64, 0)
 		n.DeletedAt = &t
 	}
+	if archived.Valid {
+		t := time.Unix(archived.Int64, 0)
+		n.ArchivedAt = &t
+	}
 	return n, nil
 }

internal/store/notes_test.go

@@ -29,7 +29,10 @@ func TestATagInANoteIsTheSameTagAsInATask(t *testing.T) {
 	if len(projects) != 2 {
 		t.Fatalf("read %v out of the note, want the two projects", n.Links)
 	}
-	if projects[0] != "Firma" || projects[1] != "Regnskab" {
+	// Folded: the key is a key, not a label. #firma and #Firma are the same project
+	// to everybody except a database, and the project's own spelling is on the
+	// project, which is what the interface shows.
+	if projects[0] != "firma" || projects[1] != "regnskab" {
 		t.Errorf("got %v", projects)
 	}
 }
@@ -118,10 +121,10 @@ func TestNotesAreFoundInEitherSpelling(t *testing.T) {
 	db, userID := sealedStore(t)
 	ctx := context.Background()
 
+	// The title is the first line now, so that is where it goes.
 	if err := db.SaveNote(ctx, &Note{
 		CreatedBy: userID,
-		Title:     "Grønt regnskab",
-		Body:      "Målt på årsbasis for Århus.",
+		Body:      "Grønt regnskab\n\nMålt på årsbasis for Århus.",
 	}); err != nil {
 		t.Fatal(err)
 	}
@@ -173,7 +176,9 @@ func TestWhatIsReadOutOfABody(t *testing.T) {
 		{"a hash inside a word is not a tag", "C#Sharp og x#y", nil},
 		{"a note by title", "se [[Møde med Anders]]", []NoteLink{{"note", "Møde med Anders"}}},
 		{"the same tag twice is one link", "#Firma og #Firma igen",
-			[]NoteLink{{"project", "Firma"}}},
+			[]NoteLink{{"project", "firma"}}},
+		{"two spellings are one tag", "#Firma og #firma",
+			[]NoteLink{{"project", "firma"}}},
 		{"a heading is not a tag", "# Overskrift", nil},
 	} {
 		t.Run(c.name, func(t *testing.T) {
@@ -245,3 +250,186 @@ func TestTheProjectCountIsWhatIsLeft(t *testing.T) {
 		t.Errorf("after deleting one, the count is %d, want 1", n)
 	}
 }
+
+// The title follows the first line, always — not only the first time.
+//
+// Derived once and then left alone, it goes stale the moment somebody rewrites
+// the opening, and the list ends up calling a note by a name that is nowhere in
+// it. That is exactly what happened: a note headed "Ny note" was listed as
+// "fdgfgfgh", which was what its first line had been some edits ago.
+func TestTheTitleFollowsTheFirstLine(t *testing.T) {
+	db, userID := sealedStore(t)
+	ctx := context.Background()
+
+	n := &Note{CreatedBy: userID, Body: "Første udgave\n\nnoget tekst"}
+	if err := db.SaveNote(ctx, n); err != nil {
+		t.Fatal(err)
+	}
+	if n.Title != "Første udgave" {
+		t.Fatalf("title started as %q", n.Title)
+	}
+
+	n.Body = "# Ny note\n\nDette er mit nye noteprogram"
+	if err := db.SaveNote(ctx, n); err != nil {
+		t.Fatal(err)
+	}
+	if n.Title != "Ny note" {
+		t.Errorf("after rewriting the first line the title is %q", n.Title)
+	}
+
+	back, err := db.Note(ctx, n.ID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if back.Title != "Ny note" {
+		t.Errorf("the stored title is %q", back.Title)
+	}
+
+	// And a title cannot be set beside the text, because then the two can disagree.
+	n.Title = "noget andet"
+	if err := db.SaveNote(ctx, n); err != nil {
+		t.Fatal(err)
+	}
+	if n.Title != "Ny note" {
+		t.Errorf("a title set by hand survived as %q", n.Title)
+	}
+}
+
+// A note that names a project in the other case must still turn up on it.
+//
+// It did not, and nothing said why: the key was stored exactly as typed and
+// looked up the same way, so #garageristeriet and #GarageRisteriet were two
+// different things that looked identical to a person.
+func TestATagFindsItsProjectWhateverTheCase(t *testing.T) {
+	db, userID := sealedStore(t)
+	ctx := context.Background()
+
+	if err := db.SaveNote(ctx, &Note{
+		CreatedBy: userID,
+		Body:      "Bønnerne kommer fredag #garageristeriet",
+	}); err != nil {
+		t.Fatal(err)
+	}
+
+	for _, spelling := range []string{"GarageRisteriet", "garageristeriet", "GARAGERISTERIET"} {
+		found, err := db.NotesLinking(ctx, "project", spelling)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if len(found) != 1 {
+			t.Errorf("looking up %q found %d notes, want 1", spelling, len(found))
+		}
+	}
+
+	// A note title is a title, not a key: two notes called "Møde" and "møde" are
+	// two notes, and folding them together would merge things somebody kept apart.
+	if err := db.SaveNote(ctx, &Note{CreatedBy: userID, Body: "se [[Møde]]"}); err != nil {
+		t.Fatal(err)
+	}
+	if found, _ := db.NotesLinking(ctx, "note", "møde"); len(found) != 0 {
+		t.Error("a note title was folded")
+	}
+	if found, _ := db.NotesLinking(ctx, "note", "Møde"); len(found) != 1 {
+		t.Error("a note title did not match itself")
+	}
+}
+
+// En søgning skal svare med det, der passer bedst, øverst.
+//
+// Den sorterede efter `updated_at`, hvilket var usynligt med ti noter og
+// ubrugeligt med tolv hundrede: de blev alle importeret samme aften, så datoen
+// siger ingenting, og loftet skar så listen af ved halvtreds tilfældige rækker.
+// At søge "Tesla" svarede med en note om nginx først og noten, der hedder "Tesla
+// Model Y", bagefter — hvilket læses som en søgning, der ikke virker, fordi det
+// fra brugerens plads er præcis dét.
+func TestSearchAnswersWithTheBestMatchFirst(t *testing.T) {
+	db, userID := sealedStore(t)
+	ctx := context.Background()
+
+	// Skrevet i den rækkefølge, der ville give det forkerte svar: den, der kun
+	// nævner ordet i kroppen, gemmes sidst og har derfor den nyeste dato.
+	for _, body := range []string{
+		"# Tesla Model Y\n\nBilen selv.\n",
+		"# Ladestandere\n\nNoter om Tesla og andre mærker.\n",
+		"# nginx proxy manager backup\n\nEn konfiguration. Tesla nævnes i forbifarten.\n",
+	} {
+		if err := db.SaveNote(ctx, &Note{CreatedBy: userID, Body: body}); err != nil {
+			t.Fatal(err)
+		}
+	}
+
+	found, err := db.SearchNotes(ctx, "Tesla", 10)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(found) != 3 {
+		t.Fatalf("fandt %d noter, ventede 3", len(found))
+	}
+	if found[0].Title != "Tesla Model Y" {
+		t.Errorf("øverst stod %q; den note, der hedder det, man søgte efter, skal stå først", found[0].Title)
+	}
+}
+
+// A word inside a word.
+//
+// Reported as "søgning har ikke det store held": a note holding
+// `gamerule keepInventory true` could not be found by typing "keep inventory".
+// The index is built of tokens, and `keepInventory` is one token — so the two
+// words are nowhere, and the search says there is nothing while the note is right
+// there.
+//
+// A decade of notes is full of these: commands, identifiers, file names. Every one
+// of them is several words the index thinks is one.
+func TestAWordInsideAWordIsStillFound(t *testing.T) {
+	db, userID := sealedStore(t)
+	ctx := context.Background()
+
+	if err := db.SaveNote(ctx, &Note{
+		CreatedBy: userID,
+		Body:      "Minecraft Bedrock\n\ngamerule keepInventory true",
+	}); err != nil {
+		t.Fatal(err)
+	}
+	// A second note, so a fallback that simply returns everything would be caught.
+	if err := db.SaveNote(ctx, &Note{
+		CreatedBy: userID,
+		Body:      "Indkøb\n\nKaffe og filtre",
+	}); err != nil {
+		t.Fatal(err)
+	}
+
+	for _, q := range []string{
+		"keep inventory", // the two words, which is how somebody looks for it
+		"inventory",      // the tail on its own — no prefix query can reach this
+		"keepinventory",  // written as one, which the index does hold
+		"KEEP INVENTORY", // and case is not a question anybody is asking
+		"vacuum",         // not in either note
+	} {
+		found, err := db.SearchNotes(ctx, q, 10)
+		if err != nil {
+			t.Fatalf("%q: %v", q, err)
+		}
+		want := 1
+		if q == "vacuum" {
+			want = 0
+		}
+		if len(found) != want {
+			t.Errorf("%q found %d notes, want %d", q, len(found), want)
+			continue
+		}
+		if want == 1 && found[0].Title != "Minecraft Bedrock" {
+			t.Errorf("%q found %q", q, found[0].Title)
+		}
+	}
+
+	// The fast path is still the fast path: a word the index does hold must not be
+	// answered by the scan, or the ranking that was built for twelve hundred notes
+	// is quietly gone.
+	found, err := db.SearchNotes(ctx, "Bedrock", 10)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(found) != 1 {
+		t.Fatalf("an ordinary word found %d notes", len(found))
+	}
+}

internal/store/notifications.go

@@ -140,11 +140,17 @@ func (db *DB) SavePushSubscription(ctx context.Context, sub *PushSubscription) e
 	if sub.ID == "" {
 		sub.ID = NewID()
 	}
+	// The upsert no longer moves the row between accounts.
+	//
+	// `user_id = excluded.user_id` was in the DO UPDATE, so anybody who learned
+	// another person's endpoint could claim it by subscribing with it: the
+	// victim's device would then receive the claimant's notifications and none of
+	// its own. A re-subscribe from the same person still refreshes the keys, which
+	// is what the upsert is actually for.
 	_, err := db.ExecContext(ctx,
 		`INSERT INTO push_subscriptions (id, user_id, endpoint, p256dh, auth, user_agent, created_at)
 		 VALUES (?, ?, ?, ?, ?, ?, ?)
 		 ON CONFLICT (endpoint) DO UPDATE SET
-		     user_id = excluded.user_id,
 		     p256dh = excluded.p256dh,
 		     auth = excluded.auth,
 		     user_agent = excluded.user_agent,
@@ -175,7 +181,21 @@ func (db *DB) ListPushSubscriptions(ctx context.Context, userID string) ([]PushS
 	return out, rows.Err()
 }
 
-func (db *DB) DeletePushSubscription(ctx context.Context, endpoint string) error {
+// DeletePushSubscription removes one of this person's devices.
+//
+// Scoped by user as well as by endpoint. It was endpoint alone, which meant
+// anybody who learned somebody else's endpoint could silently unsubscribe their
+// phone — and the endpoint is the only thing about a subscription that ever
+// leaves the browser.
+func (db *DB) DeletePushSubscription(ctx context.Context, userID, endpoint string) error {
+	_, err := db.ExecContext(ctx,
+		`DELETE FROM push_subscriptions WHERE endpoint = ? AND user_id = ?`, endpoint, userID)
+	return err
+}
+
+// dropPushEndpoint removes a subscription the push service has declared dead.
+// Unexported so the only *request* path to a delete stays the scoped one.
+func (db *DB) dropPushEndpoint(ctx context.Context, endpoint string) error {
 	_, err := db.ExecContext(ctx, `DELETE FROM push_subscriptions WHERE endpoint = ?`, endpoint)
 	return err
 }
@@ -186,7 +206,10 @@ func (db *DB) DeletePushSubscription(ctx context.Context, endpoint string) error
 // silently unsubscribing somebody's phone.
 func (db *DB) RecordPushFailure(ctx context.Context, endpoint string, permanent bool) error {
 	if permanent {
-		return db.DeletePushSubscription(ctx, endpoint)
+		// Not scoped by user, and that is right here: this is the push service
+		// saying the endpoint is gone, not a person asking for something. There is
+		// no caller to check against — the caller is the delivery job.
+		return db.dropPushEndpoint(ctx, endpoint)
 	}
 	_, err := db.ExecContext(ctx,
 		`UPDATE push_subscriptions SET failures = failures + 1 WHERE endpoint = ?`, endpoint)
@@ -289,6 +312,11 @@ var secretFields = map[string]bool{
 	"access_token":  true,
 	"password":      true,
 	"client_secret": true,
+	// The AI provider's key. Missed when this list was written, and it is exactly
+	// the same kind of thing as the rest: a live credential, in a settings blob,
+	// in a database anybody with a backup file can read. Existing rows convert
+	// themselves the next time the settings are saved.
+	"api_key": true,
 }
 
 // seal returns a copy of values with the secret fields sealed. Without a key it
@@ -363,11 +391,15 @@ func (db *DB) SetUserSettings(ctx context.Context, userID, scope string, values
 	if err != nil {
 		return err
 	}
+	// On (user_id, scope), which is the key since 0025. It used to be on `user_id`
+	// alone and set `scope = excluded.scope` — so writing one scope did not add a
+	// row beside the others, it took theirs and renamed it. The `ai`, `gmail` and
+	// `calendar` settings each deleted the other two, and the write reported
+	// success every time.
 	_, err = db.ExecContext(ctx, `
 		INSERT INTO user_settings (user_id, scope, values_json, updated_at)
 		VALUES (?, ?, ?, ?)
-		ON CONFLICT (user_id) DO UPDATE SET
-		    scope = excluded.scope,
+		ON CONFLICT (user_id, scope) DO UPDATE SET
 		    values_json = excluded.values_json,
 		    updated_at = excluded.updated_at`,
 		userID, scope, string(raw), time.Now().Unix())

internal/store/projects.go

@@ -646,6 +646,35 @@ func (db *DB) ReorderProjects(ctx context.Context, userID string, ids []string)
 	})
 }
 
+// ReorderSections writes the order of one project's sections, top to bottom.
+//
+// The whole list at once, the same as ReorderProjects and for the same reasons: a
+// project has a handful of sections, so writing 0, 1, 2 … is one small
+// transaction that cannot run out of precision, and a list is impossible to get
+// into the half-ordered state a sequence of individual moves leaves behind when
+// one of them fails.
+//
+// Scoped to the project rather than to a user. A section has no owner of its own —
+// it belongs to a project, and whether the caller may rearrange it is a question
+// about that project, which the handler has already asked. Ids belonging to some
+// other project are skipped by the WHERE clause rather than refused, so a stale
+// list from a client that has just moved a section elsewhere cannot rearrange a
+// project the caller was never looking at.
+func (db *DB) ReorderSections(ctx context.Context, projectID string, ids []string) error {
+	return db.Tx(ctx, func(tx *sql.Tx) error {
+		now := time.Now().Unix()
+		for i, id := range ids {
+			if _, err := tx.ExecContext(ctx,
+				`UPDATE sections SET sort_order = ?, updated_at = ?
+				 WHERE id = ? AND project_id = ? AND deleted_at IS NULL`,
+				float64(i), now, id, projectID); err != nil {
+				return err
+			}
+		}
+		return nil
+	})
+}
+
 // SectionByName resolves a "/name" from quick add within one project.
 //
 // Case-insensitive, and scoped to the project the task is landing in — a section

internal/store/search.go

@@ -20,6 +20,13 @@ func FoldDanish(s string) string {
 	return r.Replace(s)
 }
 
+// The ceilings on a search. See MatchExprOver for why they exist; both are far
+// above anything a person types and far below anything that costs.
+const (
+	maxSearchInput = 512
+	maxSearchTerms = 16
+)
+
 // MatchExpr turns what someone typed into the search box into an FTS5 MATCH
 // expression.
 //
@@ -51,6 +58,23 @@ func MatchExprOver(query string, columns ...string) string {
 		return ""
 	}
 
+	// Capped, because the expression is built from the input and then run inside
+	// SQLite on one of a handful of pooled connections.
+	//
+	// Every term becomes roughly fifty bytes of FTS5, and every one of them is a
+	// prefix query — which is what makes ⌘K feel like it searches as you type, and
+	// also what makes each one expensive. A quarter of a megabyte pasted into the
+	// box became a two-megabyte MATCH expression and half a minute inside SQLite,
+	// holding a connection the whole time. A few of those at once and the database
+	// is unavailable to everybody on the instance, logins included.
+	//
+	// Sixteen terms is far past anything a person types into a search box and
+	// nowhere near enough to hurt. Silently, because a message about a limit
+	// nobody has reached on purpose is noise.
+	if len(terms) > maxSearchTerms {
+		terms = terms[:maxSearchTerms]
+	}
+
 	var b strings.Builder
 	for i, term := range terms {
 		if i > 0 {
@@ -66,10 +90,29 @@ func MatchExprOver(query string, columns ...string) string {
 	return b.String()
 }
 
+// SearchTerms is the words a query asks about, capped the same way the MATCH
+// expression is.
+//
+// Exported because two searches need the same list: the FTS expression is built
+// from it, and so is the substring arm that finds a word living inside another
+// word. Two tokenizers would be two answers to "what did they type".
+func SearchTerms(query string) []string {
+	terms := tokenize(query)
+	if len(terms) > maxSearchTerms {
+		terms = terms[:maxSearchTerms]
+	}
+	return terms
+}
+
 // tokenize splits on everything that is not a letter or a digit. Splitting on
 // punctuation rather than whitespace alone means "q3/2026" searches for "q3" and
 // "2026" instead of for a term FTS5's own tokenizer would never have indexed.
 func tokenize(query string) []string {
+	// Trimmed before it is split, so a megabyte of text is not walked rune by rune
+	// only to have all but sixteen of the results thrown away.
+	if len(query) > maxSearchInput {
+		query = query[:maxSearchInput]
+	}
 	fields := strings.FieldsFunc(query, func(r rune) bool {
 		return !unicode.IsLetter(r) && !unicode.IsDigit(r)
 	})

internal/store/secrets_test.go

@@ -124,3 +124,156 @@ func sealedStore(t *testing.T) (*DB, string) {
 	}
 	return db, user.ID
 }
+
+// Three integrations, one person, and none of them may delete the others.
+//
+// `user_settings` had `user_id` as its whole primary key and an upsert that
+// rewrote `scope` on conflict, so every person had exactly one settings row and
+// the last write won the lot: saving an AI provider deleted the Gmail connection,
+// and connecting a calendar deleted the AI provider. The write reported success
+// each time, which is why it was reported as "the AI settings are not saved"
+// rather than as "connecting the calendar deleted them".
+//
+// Written against the store rather than the handlers, because the shape was the
+// bug: every caller was correct on its own.
+func TestOnePersonCanHaveSettingsForMoreThanOneThing(t *testing.T) {
+	db, userID := sealedStore(t)
+	ctx := context.Background()
+
+	want := map[string]map[string]any{
+		"ai":       {"provider": "anthropic", "model": "claude-sonnet-5", "api_key": "sk-ant-xxx"},
+		"gmail":    {"refresh_token": "1//0-gmail", "label": "Verdande"},
+		"calendar": {"refresh_token": "1//0-calendar", "calendar_id": "primary"},
+	}
+	// In this order on purpose: the AI settings are written first and read last,
+	// so a scope that steals the row is caught by the one written earliest.
+	for _, scope := range []string{"ai", "gmail", "calendar"} {
+		if err := db.SetUserSettings(ctx, userID, scope, want[scope]); err != nil {
+			t.Fatalf("save %s: %v", scope, err)
+		}
+	}
+
+	for _, scope := range []string{"ai", "gmail", "calendar"} {
+		got, err := db.UserSettings(ctx, userID, scope)
+		if err != nil {
+			t.Fatalf("read %s: %v", scope, err)
+		}
+		for key, value := range want[scope] {
+			if got[key] != value {
+				t.Errorf("%s.%s is %v, want %v", scope, key, got[key], value)
+			}
+		}
+	}
+
+	// And a second write to one scope updates it rather than adding another row —
+	// the upsert still has to upsert.
+	if err := db.SetUserSettings(ctx, userID, "ai", map[string]any{"provider": "openai"}); err != nil {
+		t.Fatal(err)
+	}
+	var rows int
+	if err := db.QueryRowContext(ctx,
+		`SELECT count(*) FROM user_settings WHERE user_id = ?`, userID).Scan(&rows); err != nil {
+		t.Fatal(err)
+	}
+	if rows != 3 {
+		t.Errorf("the person has %d settings rows, want 3", rows)
+	}
+	back, err := db.UserSettings(ctx, userID, "ai")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if back["provider"] != "openai" {
+		t.Errorf("the second write did not land: %v", back["provider"])
+	}
+}
+
+// The upgrade path, which is the one nobody runs: an existing database with a row
+// in the old shape, opened by a binary that carries 0025.
+//
+// Every other test here starts empty and runs all the migrations in order, which
+// exercises the migration's SQL but not its *situation*. The situation is a table
+// that already holds somebody's settings, and the question is whether they come
+// through it and whether a second scope can be written afterwards.
+func TestSettingsSurviveTheUpgradeToPerScopeRows(t *testing.T) {
+	dir := t.TempDir()
+	path := filepath.Join(dir, "test.db")
+
+	db, err := Open(path)
+	if err != nil {
+		t.Fatal(err)
+	}
+	ctx := context.Background()
+	user := &User{Email: "[email protected]", Name: "Kristian"}
+	if err := db.CreateUser(ctx, user, "Indbakke"); err != nil {
+		t.Fatal(err)
+	}
+
+	// Wind the database back to how v0.33.3 left it: user_id as the whole primary
+	// key, and 0025 not yet applied.
+	for _, stmt := range []string{
+		`PRAGMA foreign_keys = OFF`,
+		`CREATE TABLE us_old (
+			user_id     TEXT PRIMARY KEY REFERENCES users (id) ON DELETE CASCADE,
+			scope       TEXT NOT NULL DEFAULT 'general',
+			values_json TEXT NOT NULL DEFAULT '{}',
+			updated_at  INTEGER NOT NULL
+		)`,
+		`INSERT INTO us_old (user_id, scope, values_json, updated_at)
+		 SELECT user_id, scope, values_json, updated_at FROM user_settings`,
+		`DROP TABLE user_settings`,
+		`ALTER TABLE us_old RENAME TO user_settings`,
+		`DELETE FROM schema_migrations WHERE name = '0025_user_settings_per_scope.sql'`,
+		`PRAGMA foreign_keys = ON`,
+	} {
+		if _, err := db.ExecContext(ctx, stmt); err != nil {
+			t.Fatalf("rewind (%s): %v", stmt, err)
+		}
+	}
+
+	// A Gmail connection, written the way the old upsert wrote one.
+	if _, err := db.ExecContext(ctx, `
+		INSERT INTO user_settings (user_id, scope, values_json, updated_at)
+		VALUES (?, 'gmail', '{"label":"Verdande"}', 0)`, user.ID); err != nil {
+		t.Fatal(err)
+	}
+	if err := db.Close(); err != nil {
+		t.Fatal(err)
+	}
+
+	// And now the new binary opens it.
+	db, err = Open(path)
+	if err != nil {
+		t.Fatalf("the upgrade refused to open the database: %v", err)
+	}
+	defer db.Close()
+
+	gmail, err := db.UserSettings(ctx, user.ID, "gmail")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if gmail["label"] != "Verdande" {
+		t.Errorf("the Gmail settings did not survive the migration: %v", gmail)
+	}
+
+	// The thing that was reported: set up the AI provider, and have it still be
+	// there afterwards.
+	if err := db.SetUserSettings(ctx, user.ID, "ai", map[string]any{
+		"provider": "anthropic", "model": "claude-sonnet-5",
+	}); err != nil {
+		t.Fatalf("saving the AI provider after the upgrade: %v", err)
+	}
+	ai, err := db.UserSettings(ctx, user.ID, "ai")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if ai["provider"] != "anthropic" {
+		t.Errorf("the AI provider is %v after the upgrade, want anthropic", ai["provider"])
+	}
+	again, err := db.UserSettings(ctx, user.ID, "gmail")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if again["label"] != "Verdande" {
+		t.Errorf("saving the AI provider took the Gmail settings: %v", again)
+	}
+}

internal/store/tasks.go

@@ -166,15 +166,42 @@ func (db *DB) ListTasks(ctx context.Context, userID string, f TaskFilter) ([]Tas
 		// labels are short, and their names are typed by the person searching for
 		// them, so there is no spelling to be generous about. The diacritic
 		// folding that matters for task text does not earn a second index here.
+		//
+		// The third arm is a word inside a word. An index is built of tokens, and
+		// `SpeedAdmin` is one of them — so "speed admin" asks for two words that are
+		// nowhere. A prefix query gets half of it (`speed*` matches, `admin*` cannot)
+		// and the two are joined with AND, so the half that works is thrown away.
+		//
+		// Notes got the same arm, and for the same reason. Having it in one of the
+		// two would be worse than having it in neither: "it finds it in my notes but
+		// not in my tasks" is a bug report waiting, and the answer to it would be
+		// this line.
+		//
+		// It scans, and it only ever runs when somebody typed something in the box —
+		// Today and Kommende do not set `Search`. Every term has to appear, so the
+		// arms are ANDed with each other while the whole thing is ORed with the two
+		// above.
+		inside := make([]string, 0, maxSearchTerms)
+		insideArgs := make([]any, 0, maxSearchTerms)
+		for _, term := range SearchTerms(f.Search) {
+			inside = append(inside, "t.fold LIKE ?")
+			insideArgs = append(insideArgs, "%"+FoldDanish(term)+"%")
+		}
+		text := ""
+		if len(inside) > 0 {
+			text = " OR (" + strings.Join(inside, " AND ") + ")"
+		}
+
 		where = append(where, `(
 			t.rowid IN (SELECT rowid FROM tasks_fts WHERE tasks_fts MATCH ?)
 			OR t.id IN (
 				SELECT tl.task_id FROM task_labels tl
 				JOIN labels l ON l.id = tl.label_id
 				WHERE lower(l.name) LIKE ?
-			)
+			)`+text+`
 		)`)
 		args = append(args, expr, "%"+strings.ToLower(strings.TrimSpace(f.Search))+"%")
+		args = append(args, insideArgs...)
 	}
 	if f.FilterSQL != "" {
 		where = append(where, "("+f.FilterSQL+")")

internal/store/users.go

@@ -16,6 +16,11 @@ var (
 	ErrNotFound      = errors.New("store: not found")
 	ErrEmailInUse    = errors.New("store: that email address already has an account")
 	ErrInviteInvalid = errors.New("store: invite is not valid")
+	// ErrDuplicate er en unik nøgle, der blev brudt, oversat til noget en handler
+	// kan spørge om. Drivereren udstiller ikke sin egen fejltype brugbart, og en
+	// handler, der matcher på tekst, er en handler, der går i stykker den dag
+	// driveren omformulerer sig.
+	ErrDuplicate = errors.New("store: already exists")
 )
 
 type User struct {
@@ -36,8 +41,13 @@ type User struct {
 	// is as true on the laptop as on the desktop. The sidebar's *width* is the
 	// opposite case and is stored per browser.
 	SidebarCollapsed []string
-	CreatedAt        time.Time
-	UpdatedAt        time.Time
+
+	// NavOrder is the order this person wants the fixed views in, by key. Empty
+	// means the order the program ships with. Unknown keys are ignored and missing
+	// ones are appended, so adding a view later is not a migration.
+	NavOrder  []string
+	CreatedAt time.Time
+	UpdatedAt time.Time
 }
 
 // NormalizeEmail is the one place an address is canonicalised. Addresses arrive
@@ -104,7 +114,7 @@ func (db *DB) UserByID(ctx context.Context, id string) (*User, error) {
 }
 
 const userColumns = `id, email, name, password_hash, totp_secret, totp_enabled,
-	avatar_color, timezone, locale, is_admin, sidebar_collapsed, created_at, updated_at`
+	avatar_color, timezone, locale, is_admin, sidebar_collapsed, nav_order, created_at, updated_at`
 
 func (db *DB) scanUser(ctx context.Context, query string, args ...any) (*User, error) {
 	var u User
@@ -112,11 +122,11 @@ func (db *DB) scanUser(ctx context.Context, query string, args ...any) (*User, e
 	var totpEnabled, isAdmin int
 	var created, updated int64
 
-	var collapsed string
+	var collapsed, navOrder string
 
 	err := db.QueryRowContext(ctx, query, args...).Scan(
 		&u.ID, &u.Email, &u.Name, &u.PasswordHash, &secret, &totpEnabled,
-		&u.AvatarColor, &u.Timezone, &u.Locale, &isAdmin, &collapsed, &created, &updated)
+		&u.AvatarColor, &u.Timezone, &u.Locale, &isAdmin, &collapsed, &navOrder, &created, &updated)
 	if errors.Is(err, sql.ErrNoRows) {
 		return nil, ErrNotFound
 	}
@@ -124,18 +134,48 @@ func (db *DB) scanUser(ctx context.Context, query string, args ...any) (*User, e
 		return nil, err
 	}
 
-	u.TOTPSecret = secret.String
+	// Opened on the way out. A row written before the key existed is returned as
+	// itself — see secret.Unseal — so this does not need a migration; a secret
+	// converts the next time it is written.
+	if plain, err := db.unsealValue(secret.String); err == nil {
+		u.TOTPSecret = plain
+	} else {
+		u.TOTPSecret = secret.String
+	}
 	u.TOTPEnabled = totpEnabled == 1
 	u.IsAdmin = isAdmin == 1
 	// A malformed value is read as "nothing folded" rather than as an error: the
 	// worst case is a sidebar that opens fully, which is the state it shipped in.
 	u.SidebarCollapsed = []string{}
 	_ = json.Unmarshal([]byte(collapsed), &u.SidebarCollapsed)
+	u.NavOrder = []string{}
+	_ = json.Unmarshal([]byte(navOrder), &u.NavOrder)
 	u.CreatedAt = time.Unix(created, 0).UTC()
 	u.UpdatedAt = time.Unix(updated, 0).UTC()
 	return &u, nil
 }
 
+// SetNavOrder records the order of the fixed views.
+func (db *DB) SetNavOrder(ctx context.Context, userID string, order []string) error {
+	if order == nil {
+		order = []string{}
+	}
+	raw, err := json.Marshal(order)
+	if err != nil {
+		return err
+	}
+	res, err := db.ExecContext(ctx,
+		`UPDATE users SET nav_order = ?, updated_at = ? WHERE id = ?`,
+		string(raw), time.Now().Unix(), userID)
+	if err != nil {
+		return err
+	}
+	if n, _ := res.RowsAffected(); n == 0 {
+		return ErrNotFound
+	}
+	return nil
+}
+
 // SetSidebarCollapsed records which sidebar headings are folded.
 //
 // Its own method rather than a field on UpdateProfile: that one backs a form with
@@ -405,9 +445,20 @@ func (db *DB) UpdateProfile(ctx context.Context, userID, name, timezone, locale
 }
 
 func (db *DB) SetTOTPSecret(ctx context.Context, userID, secret string, enabled bool) error {
+	// Sealed, like a mailbox password and for the same reason: the copies, not the
+	// server. A TOTP secret in a downloadable backup lets whoever holds the copy
+	// generate valid codes for every account on the instance — which turns the
+	// second factor from a defence into a file somebody can take home.
+	//
+	// It was missed when internal/secret was written, along with three other
+	// values; see SECURITY.md.
 	var value any
 	if secret != "" {
-		value = secret
+		sealed, err := db.sealValue(secret)
+		if err != nil {
+			return err
+		}
+		value = sealed
 	}
 	_, err := db.ExecContext(ctx,
 		`UPDATE users SET totp_secret = ?, totp_enabled = ?, updated_at = ? WHERE id = ?`,

site/index.html

@@ -6,12 +6,12 @@
 		<title>verdande — self-hosted tasks, shared</title>
 		<meta
 			name="description"
-			content="Self-hosted tasks and projects, shared. One Go binary with SQLite inside it. Your mail as an inbox, CalDAV, passkeys, and an MCP connector for Claude."
+			content="Self-hosted tasks, notes and projects, shared. One Go binary with SQLite inside it. Your mail as an inbox, a CalDAV server, notes in Markdown, passkeys, and an MCP connector for Claude."
 		/>
 		<meta name="theme-color" content="#111312" />
 
 		<meta property="og:title" content="verdande" />
-		<meta property="og:description" content="Self-hosted tasks and projects, shared. One binary, SQLite inside it." />
+		<meta property="og:description" content="Self-hosted tasks, notes and projects, shared. One binary, SQLite inside it." />
 		<meta property="og:type" content="website" />
 		<meta property="og:image" content="screenshots/today.webp" />
 		<meta property="og:image:alt" content="The Today view: projects and filters beside a list of what is due." />
@@ -76,10 +76,10 @@
 			}
 
 			.theme-toggle {
-				position: fixed;
-				top: 1rem;
-				right: 1rem;
-				z-index: 10;
+				/* In the bar now rather than floating over the corner. Fixed, it sat
+				   on top of whatever happened to scroll under it — on a narrow window
+				   that was the first screenshot's own corner. */
+				flex: none;
 				width: 2.25rem;
 				height: 2.25rem;
 				display: grid;
@@ -141,10 +141,86 @@
 				padding: 0 1.5rem;
 			}
 
+			/* --- the bar that stays -------------------------------------------
+
+			   A page this long had its only way out at the very top: somebody who
+			   read as far as "What it will not do" had to scroll back past nine
+			   screenshots to reach the documentation. The bar is the way out from
+			   wherever you are.
+
+			   `sticky` and not `fixed`: sticky keeps its space in the flow, so
+			   nothing below has to be pushed down by a number that then has to be
+			   kept in step with the bar's own height.
+
+			   Full width, with the wrap *inside* it. Put the other way round, the
+			   background would end where the column ends and the page would scroll
+			   past it on both sides. */
+			.topbar {
+				position: sticky;
+				top: 0;
+				z-index: 20;
+				background: var(--ground);
+				border-bottom: 1px solid var(--line);
+			}
+
+			.bar {
+				display: flex;
+				align-items: center;
+				gap: 1.25rem;
+				padding: 0.625rem 1.5rem;
+			}
+
+			.bar-brand {
+				display: flex;
+				align-items: center;
+				gap: 0.5rem;
+				color: var(--ink);
+				text-decoration: none;
+				font-weight: 560;
+				letter-spacing: -0.01em;
+			}
+
+			.bar-brand .rune {
+				color: var(--accent);
+				font-size: 1.125rem;
+				line-height: 1;
+			}
+
+			.bar-links {
+				display: flex;
+				align-items: center;
+				gap: 1.25rem;
+				margin-left: auto;
+				font-size: 0.875rem;
+			}
+
+			.bar-links a {
+				color: var(--ink-muted);
+				text-decoration: none;
+			}
+
+			.bar-links a:hover {
+				color: var(--ink);
+			}
+
+			/* The three in-page links go first on a narrow screen: they are the ones
+			   a phone can reach by scrolling anyway. Documentation and Source cannot
+			   be reached any other way, so they stay. */
+			@media (max-width: 640px) {
+				.bar-links .inpage {
+					display: none;
+				}
+			}
+
+			/* Or the bar covers the heading you just jumped to. */
+			:target {
+				scroll-margin-top: 4.5rem;
+			}
+
 			/* --- hero --- */
 
-			header {
-				padding: 6rem 0 4rem;
+			.hero {
+				padding: 5rem 0 3.5rem;
 				text-align: center;
 			}
 
@@ -172,7 +248,7 @@
 			}
 
 			.norn {
-				margin: 2rem auto 0;
+				margin: 0 auto 1.75rem;
 				max-width: 34rem;
 				font-size: 0.9375rem;
 				color: var(--ink-faint);
@@ -289,44 +365,104 @@
 
 			/* --- features --- */
 
+			/* A hairline between sections rather than under every heading: the page
+			   is one column, and the line says where one subject stops. */
 			section {
-				padding: 3rem 0;
+				padding: 3.5rem 0;
+				border-top: 1px solid var(--line);
 			}
 
 			h2 {
+				display: flex;
+				align-items: baseline;
+				gap: 0.75rem;
 				font-size: 1.5rem;
 				font-weight: 560;
 				letter-spacing: -0.02em;
 				margin: 0 0 2rem;
 			}
 
+			/* A short accent rule in front of every h2. The sections had nothing to
+			   mark them but their own words, and at a glance the page read as one
+			   long run of paragraphs. */
+			h2::before {
+				content: '';
+				flex: none;
+				width: 1.125rem;
+				height: 2px;
+				border-radius: 1px;
+				background: var(--accent);
+				transform: translateY(-0.35em);
+			}
+
+			/* Three groups rather than eighteen cards in a row. Grouped, the list is
+			   read as three answers — what it does, what it talks to, what it
+			   promises — and any of the three can be skipped. */
+			.group-label {
+				margin: 2.5rem 0 1rem;
+				font-size: 0.75rem;
+				font-weight: 560;
+				text-transform: uppercase;
+				letter-spacing: 0.08em;
+				color: var(--ink-faint);
+			}
+
+			.group-label:first-of-type {
+				margin-top: 0;
+			}
+
+			/* Cards with their own edges, not cells in one table.
+			   The table shared a hairline grid, which meant the last row had to be
+			   full or it was a hole in the drawing — and it was a hole, for as long
+			   as there were ten of them. A card that stands alone on its row is a
+			   card; an empty cell is a mistake. */
 			.grid {
 				display: grid;
-				grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
-				gap: 1px;
-				background: var(--line);
-				border: 1px solid var(--line);
-				border-radius: var(--radius-lg);
-				overflow: hidden;
+				grid-template-columns: repeat(auto-fit, minmax(15rem, 1fr));
+				gap: 0.875rem;
 			}
 
 			.cell {
-				background: var(--ground);
-				padding: 1.5rem;
+				background: var(--surface);
+				border: 1px solid var(--line);
+				border-radius: var(--radius-lg);
+				padding: 1.125rem 1.25rem 1.25rem;
+				transition: border-color 150ms ease;
+			}
+
+			.cell:hover {
+				border-color: var(--line-strong);
 			}
 
 			.cell h3 {
-				margin: 0 0 0.5rem;
-				font-size: 1rem;
+				margin: 0 0 0.4375rem;
+				font-size: 0.9375rem;
 				font-weight: 560;
 			}
 
 			.cell p {
 				margin: 0;
-				font-size: 0.9375rem;
+				font-size: 0.875rem;
 				color: var(--ink-muted);
 			}
 
+			.cell code {
+				font-family: var(--font-mono);
+				font-size: 0.8125em;
+				color: var(--ink);
+			}
+
+			/* A card that has something to admit rather than something to offer.
+			   It is not a footnote and it is not fine print: it is the same size as
+			   everything else, and it says the same thing the README says. */
+			.cell .caveat {
+				margin: 0.5rem 0 0;
+				padding-top: 0.5rem;
+				border-top: 1px solid var(--line);
+				font-size: 0.8125rem;
+				color: var(--ink-faint);
+			}
+
 			/* --- install --- */
 
 			pre {
@@ -374,6 +510,168 @@
 				color: var(--ink-muted);
 			}
 
+			/* Four facts under the buttons, in the place where a landing page usually
+			   puts logos it has not earned. They are the four questions somebody
+			   self-hosting asks before anything else. */
+			ul.facts {
+				list-style: none;
+				display: flex;
+				flex-wrap: wrap;
+				justify-content: center;
+				gap: 0.5rem 1.25rem;
+				margin: 2rem 0 0;
+				padding: 0;
+				font-size: 0.8125rem;
+				color: var(--ink-faint);
+			}
+
+			ul.facts li {
+				display: flex;
+				align-items: center;
+				gap: 1.25rem;
+			}
+
+			/* The separator belongs between two facts, not after the last one — so it
+			   is drawn by the item that follows it. */
+			ul.facts li + li::before {
+				content: '';
+				width: 3px;
+				height: 3px;
+				border-radius: 50%;
+				background: var(--line-strong);
+			}
+
+			/* On a phone the row wraps, and a separator drawn by the item that follows
+			   it lands at the *start* of the new line — a dot with nothing before it.
+			   No separators there; the wrap is the separation. */
+			@media (max-width: 640px) {
+				ul.facts {
+					gap: 0.375rem 1.125rem;
+				}
+
+				ul.facts li + li::before {
+					display: none;
+				}
+			}
+
+			/* Two ways to run it, side by side, because they are alternatives rather
+			   than steps. Stacked, the second read as what you do after the first. */
+			.panels {
+				display: grid;
+				grid-template-columns: repeat(auto-fit, minmax(19rem, 1fr));
+				gap: 0.875rem;
+			}
+
+			.panel {
+				background: var(--surface);
+				border: 1px solid var(--line);
+				border-radius: var(--radius-lg);
+				padding: 1.25rem;
+			}
+
+			.panel h3 {
+				margin: 0 0 0.5rem;
+				font-size: 0.9375rem;
+				font-weight: 560;
+			}
+
+			/* Sunk rather than raised: inside a card, a block in --surface would be
+			   the same colour as the card it sits in. */
+			.panel pre {
+				background: var(--ground);
+				margin: 1rem 0 0;
+			}
+
+			.panel p {
+				margin: 0;
+				font-size: 0.875rem;
+				color: var(--ink-muted);
+			}
+
+			/* Versionsnummeret i sin egen søjle, så øjet kan løbe ned ad dem uden at
+			   læse sætningerne. `ch` frem for pixels: søjlen er lige så bred som de
+			   tal, der står i den, og den følger med, hvis skriften skifter. */
+			ul.lately {
+				list-style: none;
+				margin: 1.5rem 0 0;
+				padding: 0;
+			}
+
+			ul.lately li {
+				display: grid;
+				grid-template-columns: 5ch 1fr;
+				gap: 0 1rem;
+				padding: 0.875rem 0;
+				border-top: 1px solid var(--line);
+				font-size: 0.9375rem;
+				color: var(--ink-muted);
+			}
+
+			ul.lately .ver {
+				font-family: var(--font-mono);
+				font-size: 0.8125rem;
+				color: var(--ink-faint);
+				/* Tallet står på linje med den første tekstlinje og ikke over den. */
+				line-height: 1.7;
+			}
+
+			@media (max-width: 520px) {
+				ul.lately li {
+					grid-template-columns: 1fr;
+					gap: 0.25rem;
+				}
+			}
+
+			/* Risikoen står i kort, ikke i småt.
+			   Et forbehold sat med mindre skrift end resten er et forbehold, der er
+			   skrevet for at kunne peges på bagefter — og det er den ene ting, denne
+			   side ikke skal gøre. Samme størrelse som alt andet. */
+			.risk {
+				border: 1px solid var(--line-strong);
+				border-radius: var(--radius-lg);
+				padding: 1.5rem;
+				background: var(--surface);
+			}
+
+			.risk p {
+				margin: 0 0 1rem;
+				font-size: 0.9375rem;
+				color: var(--ink-muted);
+			}
+
+			.risk p:last-child {
+				margin-bottom: 0;
+			}
+
+			.risk strong {
+				color: var(--ink);
+			}
+
+			/* The non-goals were one paragraph of seven sentences, which is the shape
+			   nobody reads. Each is its own line now, and they can be counted. */
+			ul.nogo {
+				list-style: none;
+				display: grid;
+				grid-template-columns: repeat(auto-fit, minmax(16rem, 1fr));
+				gap: 0.5rem 1.75rem;
+				margin: 0;
+				padding: 0;
+				font-size: 0.9375rem;
+				color: var(--ink-muted);
+			}
+
+			ul.nogo li {
+				position: relative;
+				padding-left: 1.25rem;
+			}
+
+			ul.nogo li::before {
+				content: '—';
+				position: absolute;
+				left: 0;
+				color: var(--ink-faint);
+			}
+
 			.demo-note {
 				margin: 1rem 0 0;
 				font-family: var(--font);
@@ -524,27 +822,38 @@
 	</head>
 
 	<body>
-		<button class="theme-toggle" type="button" aria-label="Switch between light and dark" title="Light or dark">
-			<span aria-hidden="true">◐</span>
-		</button>
-		<div class="wrap">
-			<header>
+		<div class="topbar">
+			<div class="wrap bar">
+				<a class="bar-brand" href="#top">
+					<span class="rune" aria-hidden="true">ᚹ</span>
+					verdande
+				</a>
+				<nav class="bar-links" aria-label="Sections">
+					<a class="inpage" href="#screens">Screens</a>
+					<a class="inpage" href="#features">Features</a>
+					<a class="inpage" href="#running">Running it</a>
+					<a href="https://kristianwind.github.io/verdande/">Documentation</a>
+					<a href="https://github.com/kristianwind/verdande">Source</a>
+					<button class="theme-toggle" type="button" aria-label="Switch between light and dark" title="Light or dark">
+						<span aria-hidden="true">◐</span>
+					</button>
+				</nav>
+			</div>
+		</div>
+
+		<div class="wrap" id="top">
+			<header class="hero">
 				<span class="mark" aria-hidden="true">ᚹ</span>
 				<h1>verdande</h1>
 				<p class="lede">
-					Self-hosted tasks and projects, shared with the people you share the work with.
-					One binary, SQLite inside it.
+					Self-hosted tasks, notes and projects, shared with the people you share the work
+					with. One binary, SQLite inside it.
 				</p>
 				<p class="rune-note">
 					Built to be deployed as a <strong>Rune</strong> in
 					<a href="https://github.com/kristianwind/yggdrasil">Yggdrasil Panel</a> — upload
 					the manifest, fill in two fields, press start. It also runs anywhere Docker does.
 				</p>
-				<p class="norn">
-					Verdande is one of the three Norns — the one who spins <em>that which is
-					becoming</em>. Not what has been, and not what is fated to be: the thing you are
-					in the middle of. Which is what a to-do list is.
-				</p>
 
 				<div class="actions">
 					<a class="button primary" href="https://kristianwind.github.io/verdande/self-hosting/">
@@ -553,6 +862,14 @@
 					<a class="button" href="https://github.com/kristianwind/verdande">Source</a>
 					<a class="button" href="https://kristianwind.github.io/verdande/">Documentation</a>
 				</div>
+
+				<ul class="facts">
+					<li>One Go binary</li>
+					<li>SQLite inside it</li>
+					<li>amd64 and arm64</li>
+					<li>No account anywhere but yours</li>
+					<li>MIT</li>
+				</ul>
 			</header>
 
 			<!-- No screenshot: the quick-add parser is the thing worth showing, and it
@@ -584,7 +901,7 @@
 				</div>
 			</div>
 
-			<section>
+			<section id="screens">
 				<h2>What it looks like</h2>
 				<figure class="shot only-dark">
 					<img
@@ -621,13 +938,13 @@
 					</figure>
 					<figure class="shot">
 						<img
-							src="screenshots/today-light.webp"
-							alt="The same Today view in the light theme."
+							src="screenshots/notes.webp"
+							alt="Notes: a list of notes on the left, one open on the right with headings, bullet lists, a quotation and a shell command in a code block."
 							width="1400"
 							height="900"
 							loading="lazy"
 						/>
-						<figcaption>The light theme.</figcaption>
+						<figcaption>Notes. Rich text on top, Markdown underneath.</figcaption>
 					</figure>
 					<figure class="shot">
 						<img
@@ -642,7 +959,7 @@
 					<figure class="shot">
 						<img
 							src="screenshots/detail.webp"
-							alt="A task open in the detail drawer, with its description, due date, labels, sub-tasks and comments."
+							alt="A task open in the detail drawer, with its description, priority, due date, labels, sub-tasks and an attached file."
 							width="1400"
 							height="900"
 							loading="lazy"
@@ -652,12 +969,12 @@
 					<figure class="shot">
 						<img
 							src="screenshots/themes.webp"
-							alt="The settings page showing the five themes as swatches."
+							alt="The settings page showing five themes as swatches and, below them, four looks written in the typeface each one selects."
 							width="1400"
 							height="900"
 							loading="lazy"
 						/>
-						<figcaption>Five themes, all of them measured for contrast.</figcaption>
+						<figcaption>Five themes and four looks: how bright, and how it reads.</figcaption>
 					</figure>
 					<figure class="shot">
 						<img
@@ -669,11 +986,43 @@
 						/>
 						<figcaption>What has been done on the server, across every project.</figcaption>
 					</figure>
+					<figure class="shot">
+						<img
+							src="screenshots/delegated.webp"
+							alt="Waiting on others: tasks that have been handed to somebody else, grouped under the person who has them."
+							width="1400"
+							height="900"
+							loading="lazy"
+						/>
+						<figcaption>Waiting on others — grouped by who has it.</figcaption>
+					</figure>
+					<figure class="shot">
+						<img
+							src="screenshots/notes-source.webp"
+							alt="A note with the source view open: the same note as Markdown, with headings, a list, a quotation, a wiki link and a fenced code block."
+							width="1400"
+							height="900"
+							loading="lazy"
+						/>
+						<figcaption>The same note as Markdown. What is on disk is what you see.</figcaption>
+					</figure>
+					<figure class="shot">
+						<img
+							src="screenshots/settings.webp"
+							alt="The integrations settings page: connecting Gmail with an OAuth client, and below it the calendar feed address."
+							width="1400"
+							height="900"
+							loading="lazy"
+						/>
+						<figcaption>Integrations: your mailbox, your calendar feed, your address.</figcaption>
+					</figure>
 				</div>
 			</section>
 
-			<section>
+			<section id="features">
 				<h2>What it does</h2>
+
+				<p class="group-label">Doing the work</p>
 				<div class="grid">
 					<div class="cell">
 						<h3>Reads what you type</h3>
@@ -682,6 +1031,50 @@
 							one line — in Danish and English, mixed freely.
 						</p>
 					</div>
+					<div class="cell">
+						<h3>Nothing to remember</h3>
+						<p>
+							Start typing anywhere and you are writing a task, with the letter you
+							pressed already in the field. <code>⌘K</code> goes anywhere else.
+						</p>
+					</div>
+					<div class="cell">
+						<h3>Search that reads Danish</h3>
+						<p>
+							Type <code>gron</code> and find <code>grøn</code>. Unicode does not
+							consider <code>ø</code> an accented <code>o</code>, so a search that
+							leans on that alone is broken for the people this was built for.
+						</p>
+					</div>
+					<div class="cell">
+						<h3>Repeats, and says so in words</h3>
+						<p>
+							Recurring tasks are RRULE underneath and "every other Tuesday" on the
+							screen. Reminders are absolute or relative, and go out to the devices
+							you have allowed them on.
+						</p>
+					</div>
+					<div class="cell">
+						<h3>Notes, beside the work</h3>
+						<p>
+							Rich text to write in, Markdown on disk — and a source view to see it.
+							Images are pasted or dragged in. <code>#project</code> and
+							<code>[[another note]]</code> are links, and a task shows what has been
+							written about it. Archive what is done with it; the bin is for mistakes.
+						</p>
+					</div>
+					<div class="cell">
+						<h3>Waiting on others</h3>
+						<p>
+							What you have handed to somebody else, on its own page, grouped under
+							the person who has it. The thing a shared list stops being able to tell
+							you the moment it is shared.
+						</p>
+					</div>
+				</div>
+
+				<p class="group-label">Connected to what you already use</p>
+				<div class="grid">
 					<div class="cell">
 						<h3>Shared, properly</h3>
 						<p>
@@ -696,6 +1089,27 @@
 							here. Not a read-only feed pretending.
 						</p>
 					</div>
+					<div class="cell">
+						<h3>A calendar of its own</h3>
+						<p>
+							A month or a week of what is due, and a secret ICS address to subscribe
+							to from Apple Calendar, Google or Thunderbird. A Google calendar can be
+							laid over the top, read-only.
+						</p>
+						<p class="caveat">
+							The Google half is written to Google's documentation and has not yet
+							been run against Google. The feed and CalDAV have.
+						</p>
+					</div>
+					<div class="cell">
+						<h3>Your mail, as an inbox</h3>
+						<p>
+							Star a mail in Gmail, or flag one over IMAP in iCloud or Fastmail, and
+							it becomes a task. Forward one to your own address instead and the
+							subject is parsed like anything else you type. One way: unstarring it
+							later does nothing to the task you made.
+						</p>
+					</div>
 					<div class="cell">
 						<h3>Claude, connected</h3>
 						<p>
@@ -704,35 +1118,39 @@
 						</p>
 					</div>
 					<div class="cell">
-						<h3>Your mail, as an inbox</h3>
+						<h3>AI only if you ask for it</h3>
 						<p>
-							Star a mail in Gmail, or flag one in iCloud or Fastmail, and it becomes
-							a task. Forward one to your own address instead and the subject is
-							parsed like anything else you type. One way: unstarring it later does
-							nothing to the task you made.
+							Off by default, your own key, and your choice of Anthropic, OpenAI,
+							Google or something local. Nothing leaves the server until you have
+							filled that in, and everything works without it.
 						</p>
 					</div>
+				</div>
+
+				<p class="group-label">Yours, and checkable</p>
+				<div class="grid">
 					<div class="cell">
-						<h3>Nothing to remember</h3>
+						<h3>More than one way in</h3>
 						<p>
-							Start typing anywhere and you are writing a task, with the letter you
-							pressed already in the field. Sign in with a passkey and there is no
-							password to forget either.
-						</p>
-					</div>
-					<div class="cell">
-						<h3>Yours to leave</h3>
-						<p>
-							Import from Todoist, export back to it, or take everything as JSON. The
-							round trip is tested, not promised.
+							Passkeys, or a password hashed with Argon2id and a second factor with
+							recovery codes. Every device you are signed in on is listed, and any of
+							them can be signed out from here.
 						</p>
 					</div>
 					<div class="cell">
 						<h3>Keys stay behind</h3>
 						<p>
-							Mail tokens and mailbox passwords are encrypted in the database, and the
-							key lives in a file beside it — not inside it. So a backup you download,
-							or one that ends up somewhere it should not, does not open your mail.
+							Mail tokens, mailbox passwords, second-factor secrets and AI keys are
+							encrypted in the database, and the key lives in a file beside it — not
+							inside it. So a backup you download, or one that ends up somewhere it
+							should not, does not open your mail.
+						</p>
+					</div>
+					<div class="cell">
+						<h3>Nobody signs themselves up</h3>
+						<p>
+							The first account is the administrator, and after that people arrive by
+							invitation. An address on the internet is not an open door.
 						</p>
 					</div>
 					<div class="cell">
@@ -743,50 +1161,157 @@
 							instance's record, not the person's.
 						</p>
 					</div>
+					<div class="cell">
+						<h3>Yours to leave</h3>
+						<p>
+							Import from Todoist, export back to it, take everything as JSON, or
+							hand the notes a zip of Markdown and get the same zip back out. The
+							round trip is tested, not promised.
+						</p>
+					</div>
+					<div class="cell">
+						<h3>It counts itself, out loud</h3>
+						<p>
+							Once a day an instance says it exists — a random id, the version, and
+							nothing else. No tasks, no names, no addresses. It is on to begin with,
+							the settings page prints the exact payload, and one switch stops it.
+						</p>
+					</div>
 				</div>
 			</section>
 
-			<section>
+			<section id="recently">
+				<h2>Lately</h2>
+				<p class="muted">
+					A landing page can say a project is alive; a list of what landed says it
+					better. This is not a changelog — every release has notes, and they are on
+					<a href="https://github.com/kristianwind/verdande/releases">the releases page</a>.
+				</p>
+				<ul class="lately">
+					<li>
+						<span class="ver">0.34</span>
+						Sections can be dragged into the order the work actually happens in. The
+						sidebar keeps its head still while the projects scroll.
+					</li>
+					<li>
+						<span class="ver">0.33</span>
+						Notes grew an archive, selection of many at once, pictures you can paste
+						or drag in, a source view, and a copy button on code blocks. Search
+						stopped answering by date and started answering by relevance.
+					</li>
+					<li>
+						<span class="ver">0.32</span>
+						A calendar of its own as a menu item, with a read-only Google calendar
+						that can be laid over it.
+					</li>
+					<li>
+						<span class="ver">0.31</span>
+						Mailboxes over IMAP, so flagging a mail in iCloud or Fastmail makes a
+						task — not only Gmail.
+					</li>
+					<li>
+						<span class="ver">0.30</span>
+						An installation count that says exactly what it sends, and can be turned
+						off in one click.
+					</li>
+				</ul>
+			</section>
+
+			<section id="running">
 				<h2>Running it</h2>
 
-				<h3 class="sub">As a Rune in Yggdrasil Panel</h3>
-				<p class="muted">
-					This is what it was built for. <strong>Runes → Carve a rune</strong>, upload
-					<code>rune/verdande.yaml</code>, create a server from it, set the public address
-					and your mail server, and start it. No port forwarding — give it a subdomain and
-					the panel routes it through your Cloudflare Tunnel.
-				</p>
-
-				<h3 class="sub">Or with Docker, anywhere</h3>
-				<pre><code>docker run -d --name verdande \
+				<div class="panels">
+					<div class="panel">
+						<h3>As a Rune in Yggdrasil Panel</h3>
+						<p>
+							This is what it was built for. <strong>Runes → Carve a rune</strong>,
+							upload <code>rune/verdande.yaml</code>, create a server from it, set the
+							public address and your mail server, and start it. No port forwarding —
+							give it a subdomain and the panel routes it through your Cloudflare
+							Tunnel.
+						</p>
+					</div>
+					<div class="panel">
+						<h3>Or with Docker, anywhere</h3>
+						<p>Open the address afterwards and create the first account. That one is the administrator.</p>
+						<pre><code>docker run -d --name verdande \
   -p 8080:8080 \
   -v verdande-data:/data \
   -e VERDANDE_BASE_URL=https://todo.example.dk \
   ghcr.io/kristianwind/verdande:latest</code></pre>
-				<p class="muted" style="margin-top: 1rem">
-					Open the address and create the first account. That one is the administrator.
-				</p>
+					</div>
+				</div>
+
 				<ul class="plain">
 					<li>No database to provision — SQLite is inside the binary.</li>
 					<li>Distroless image: no shell, no package manager, one static file.</li>
 					<li>amd64 and arm64, so a Raspberry Pi is fine.</li>
 					<li>Nightly backups, fourteen kept, written with <code>VACUUM INTO</code>.</li>
+					<li>Twenty-four migrations, run on start. Upgrading is pulling the new image.</li>
 				</ul>
 			</section>
 
-			<section>
+			<section id="limits">
 				<h2>What it will not do</h2>
-				<p class="muted">
-					No karma or points. No team workspaces. No native apps. No mail integration
-					beyond Gmail and the forwarding address. No languages beyond Danish and English.
-					And no sync protocol of its own — CalDAV and the API <em>are</em> the sync.
-				</p>
+				<ul class="nogo">
+					<li>No karma, streaks or points.</li>
+					<li>No team workspaces — projects and the people in them are the whole model.</li>
+					<li>No native apps. It is a PWA, and it installs on a phone.</li>
+					<li>No Outlook or Exchange: Microsoft has closed IMAP to passwords and wants its own flow.</li>
+					<li>No languages beyond Danish and English.</li>
+					<li>No sync protocol of its own — CalDAV and the API <em>are</em> the sync.</li>
+					<li>No hosted version. There is nowhere to sign up, and that is the point.</li>
+				</ul>
+			</section>
+
+			<section id="risk">
+				<h2>At your own risk</h2>
+				<div class="risk">
+					<p>
+						verdande is <strong>MIT licensed and provided as is, without warranty of
+						any kind</strong>. That sentence is in every MIT licence and it is usually
+						skipped, so here it is in the open: if you run this, you run it at your
+						own risk, and nobody is on the hook if it loses your work.
+					</p>
+					<p>
+						It is one person's project, at version 0.x, and 0.x means the shape can
+						still change. <strong>You host it, so the data and the backups are
+						yours.</strong> It writes a backup every night and keeps fourteen — and a
+						backup nobody has ever restored is not yet a backup. Restore one before
+						you need to.
+					</p>
+					<p>
+						Security is worked on rather than claimed. There have been two full
+						reviews of the code, every finding is written down and closed, and what is
+						protected and what is not is spelled out in
+						<a href="https://github.com/kristianwind/verdande/blob/main/SECURITY.md">SECURITY.md</a>
+						— including the parts that are a deliberate trade-off. <strong>Nobody
+						outside the project has audited it.</strong> The last review found two ways
+						to reach something you should not and closed both; a third review will find
+						more, which is the point of having one.
+					</p>
+					<p>
+						It is built to sit behind something — a tunnel, a reverse proxy, a VPN —
+						put there by somebody who knows what they exposed. Found a hole? Mail it
+						rather than opening an issue; the address is in SECURITY.md and you get an
+						answer within a week.
+					</p>
+				</div>
 			</section>
 
 			<footer>
+				<!-- The Norn belongs at the end. It was the third paragraph of the hero,
+				     where it stood between somebody arriving and the buttons they came
+				     for — and it is a closing thought, not an opening one. -->
+				<p class="norn">
+					Verdande is one of the three Norns — the one who spins <em>that which is
+					becoming</em>. Not what has been, and not what is fated to be: the thing you are
+					in the middle of. Which is what a to-do list is.
+				</p>
 				<p>
 					MIT licensed ·
 					<a href="https://github.com/kristianwind/verdande">github.com/kristianwind/verdande</a>
+					· <a href="https://kristianwind.github.io/verdande/">Documentation</a>
 				</p>
 				<p>
 					Built to run as a Rune in