fix(notes): stjerne og arkiv står oven på hinanden

To knapper ved siden af hinanden er toogfyrre pixels taget fra en liste, der er
tre hundrede bred — og de er det, man rører en gang imellem, mens titlen og
uddraget er det, man læser hele tiden. I en søjle koster de toogtyve.

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

.gitignore

@@ -60,3 +60,12 @@ node_modules.nosync/
 # accident — 8.9 MB of macOS binary — and `go build ./tools/shots` without -o puts
 # it right back.
 /shots
+
+# The working handover. It names the panel, the server id and the production
+# address — a map of one person's setup, which does not belong in a public repo.
+# 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/

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

@@ -74,6 +74,10 @@ func run() error {
 	defer stopJobs()
 	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 +64,45 @@ 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
+
+| Variable | Default | What it does |
+|---|---|---|
+| `VERDANDE_SECRET_KEY` | — | Encrypts the mail tokens and mailbox passwords in the database. 32 bytes of base64. |
+
+Mail tokens and [mailbox](mailboxes.md) passwords are encrypted at rest, and the
+key does not live in the database. That is the whole point: **backups can be
+downloaded through the interface**, so a copy that ends up somewhere it should
+not would otherwise open your mail.
+
+Leave the variable empty and verdande writes a key to `secret.key` in the data
+directory on first start, mode `0600`. Backups are a `VACUUM INTO` of the
+database alone, so the key file is not in them.
+
+Generate one yourself if you would rather keep it out of the volume entirely:
+
+```
+openssl rand -base64 32
+```
+
+!!! warning "Lose the key and the mailboxes must be reconnected"
+    Nothing else is lost — tasks, projects, files and history are not encrypted —
+    but a token that cannot be decrypted cannot be used, and there is no way back
+    from a key that is gone. If you restore a database somewhere new, bring
+    `secret.key` with it, or set `VERDANDE_SECRET_KEY` to the same value.
+
+A database written before there was a key is read as it stands and encrypted the
+next time each value is written, so turning this on costs nobody a reconnection.
 
 ## Update checks
 
@@ -64,9 +113,13 @@ own mailbox from **Settings → Gmail**. The redirect URI is derived from
 | `VERDANDE_PANEL_TOKEN` | — | An API token from that panel, belonging to somebody with control of this server. |
 | `VERDANDE_PANEL_SERVER_ID` | — | Which server to restart — the id in the panel's URL. |
 
-All three together let **Indstillinger → Notifikationer** restart this instance,
+All three together let **Settings → Notifications** restart this instance,
 which is also how it picks up a new version: a container cannot replace its own
-image, so the panel recreates it and pulls `:latest` on the way. Any one of the
+image, so the panel recreates it and pulls `:latest` on the way. The request asks
+the panel for a *scheduled* restart rather than an immediate one — an immediate
+one is carried out while the request is still open, and stopping the container
+kills the very process waiting for the answer, so the panel never gets to the
+half that starts it again. Any one of the
 three alone does nothing, and the page names the ones that are missing.
 
 The token is a panel credential with control over that server. Anybody who can

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

@@ -0,0 +1,87 @@
+# Mailboxes
+
+Star a mail and it becomes a task.
+
+This is the other direction from [mail to task](mail.md): instead of forwarding
+something, Verdande reads a mailbox you connect and makes a task out of anything
+you have flagged. Nothing else in the mailbox is touched, and nothing is ever
+sent.
+
+Each mailbox belongs to the person who connected it. Two people on one instance
+connect their own and see only their own — there is no shared inbox and no
+administrator who can read yours.
+
+## Gmail
+
+**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#google).
+Once it is set up, each person connects their own mailbox through it.
+
+Choose what makes a task:
+
+| Trigger | What it reads |
+|---|---|
+| Starred | Anything you have starred |
+| Label | Anything carrying a label you name |
+
+!!! note "The app stays Internal if your client is Internal"
+    An OAuth client registered as *Internal* in a Google Workspace can only be
+    used by accounts in that workspace. A personal `@gmail.com` address will be
+    refused with `org_internal`, and that is the client working as configured.
+    Switching to *External* means refresh tokens that expire every seven days
+    until Google has verified the app — for one personal account, forwarding to
+    your [mail-to-task address](mail.md) is the shorter road.
+
+## iCloud, Fastmail and anything else over IMAP
+
+**Settings → Integrations → Mailboxes → Add a mailbox.**
+
+You need three things:
+
+| Field | Example |
+|---|---|
+| IMAP server | `imap.mail.me.com:993` |
+| Username | your address |
+| App password | not your ordinary password — see below |
+
+The connection is tested before it is saved. A mailbox that cannot be read is
+refused while you are still looking at the form, rather than accepted and then
+failing quietly every ten minutes.
+
+Flag a message — the flag, not unread — and it becomes a task on the next sweep.
+Unread is a state you are still using yourself, and a sync that consumed it would
+be taking something away.
+
+### App passwords
+
+Every host worth naming issues a separate password for applications, which you
+can withdraw on its own without changing the one you sign in with. Use that.
+
+- **iCloud** — [appleid.apple.com](https://appleid.apple.com) → Sign-In and
+  Security → App-Specific Passwords
+- **Fastmail** — Settings → Privacy & Security → Integrations → New app password
+
+The password is [encrypted at rest](configuration.md#secrets), and it is never
+returned by the API once saved.
+
+### Office 365 does not work here
+
+Microsoft has closed IMAP to passwords; it wants its own OAuth flow. There is no
+app password that will get you in, and a mailbox pointed at `outlook.office365.com`
+will be refused. Forward to your [mail-to-task address](mail.md) instead.
+
+## How often
+
+Every ten minutes, in the background. **Fetch now** does it immediately, which is
+for when you have just connected something and want to see it work.
+
+A run reads at most twenty-five messages, so a mailbox with years of flagged mail
+in it fills up over several sweeps rather than in one.
+
+## Disconnecting
+
+**Disconnect** on the mailbox. The tasks it made stay — they are your work now,
+not the mailbox's. Nothing is read after that, and the stored credential is
+deleted rather than merely disabled.

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]
@@ -2477,6 +2705,363 @@ 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]
+      summary: The mailboxes this person has connected.
+      responses:
+        "200":
+          description: OK
+          content:
+            application/json:
+              schema:
+                type: object
+                properties:
+                  mailboxes:
+                    type: array
+                    items: { $ref: "#/components/schemas/Mailbox" }
+    post:
+      tags: [integrations]
+      summary: Connect a mailbox over IMAP.
+      description: >
+        The connection is tested before it is saved, so a mailbox that cannot be
+        read is refused here rather than failing quietly every ten minutes.
+      requestBody:
+        required: true
+        content:
+          application/json:
+            schema:
+              type: object
+              required: [host, username, password]
+              properties:
+                name: { type: string }
+                host: { type: string, example: "imap.mail.me.com:993" }
+                username: { type: string }
+                password: { type: string, description: "An app-specific password on every host worth naming. Stored sealed." }
+                folder: { type: string, default: INBOX }
+      responses:
+        "201":
+          description: Connected
+          content:
+            application/json:
+              schema: { $ref: "#/components/schemas/Mailbox" }
+        "400": { $ref: "#/components/responses/BadRequest" }
+        "409": { description: That mailbox is already connected }
+        "422": { $ref: "#/components/responses/Upstream" }
+
+  /api/v1/mailboxes/{mailboxID}:
+    delete:
+      tags: [integrations]
+      summary: Disconnect a mailbox. The tasks it made stay.
+      parameters:
+        - name: mailboxID
+          in: path
+          required: true
+          schema: { type: string }
+      responses:
+        "204": { description: Disconnected }
+
+  /api/v1/mailboxes/{mailboxID}/sync:
+    post:
+      tags: [integrations]
+      summary: Read one mailbox now.
+      parameters:
+        - name: mailboxID
+          in: path
+          required: true
+          schema: { type: string }
+      responses:
+        "200":
+          description: OK
+          content:
+            application/json:
+              schema:
+                type: object
+                properties:
+                  created: { type: integer }
+                  partial:
+                    type: boolean
+                    description: The run hit its time budget. What it made is kept.
+        "404": { $ref: "#/components/responses/NotFound" }
+        "422": { $ref: "#/components/responses/Upstream" }
+
   /api/v1/ai/settings:
     get:
       tags: [integrations]
@@ -2883,6 +3468,26 @@ 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]
@@ -3065,6 +3670,40 @@ 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:
@@ -3082,6 +3721,103 @@ 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.
+      properties:
+        id: { type: string }
+        kind: { type: string, enum: [gmail, imap] }
+        name: { type: string }
+        host: { type: string }
+        username: { type: string }
+        folder: { type: string }
+        last_uid: { type: integer }
+        last_sync_at: { type: string, format: date-time }
+        created_at: { type: string, format: date-time }
+
     Error:
       type: object
       description: |

docs/quick-add.md

@@ -70,7 +70,22 @@ an error message and a lost thought.
     write it, and guessing month-first would silently move a date by months rather
     than failing visibly.
 
-## The shortcuts
+## Just start typing
 
-Press ++q++ to jump to the quick-add box from anywhere, ++t++ for Today, ++u++ for
-Upcoming, ++cmd+k++ to search, and ++question++ for the full list.
+There is no shortcut to remember. Press a letter anywhere in the app and you are
+writing a task, with the letter you pressed already in the field. The thought does
+not have to survive a journey to find somewhere to put it.
+
+It only fires when nothing else has focus — a key pressed at a field, a button or
+a link belongs to that thing.
+
+Under the field is a line saying what the parser reads: `#` project, `/` section,
+`@` label, `p1` priority, and an example date. It appears while you are typing,
+which is the one moment a placeholder cannot help you.
+
+++cmd+k++ opens the palette — search, and navigation to anywhere in the app.
+
+!!! note "The single letters used to navigate"
+    ++t++ for Today and ++u++ for Upcoming are gone. One keyboard cannot both
+    spell *tal med Anders* and jump to Today on the same ++t++, and capturing is
+    the thing done fifty times a day. The palette does the rest.

docs/signing-in.md

@@ -0,0 +1,39 @@
+# Signing in
+
+Three ways in, and you can have all of them at once.
+
+## A password
+
+What the first account is created with. Nothing is emailed, nothing is registered
+anywhere: the first person to open a fresh instance creates the administrator
+account, and after that people arrive by invite link.
+
+## A code on top of it
+
+**Settings → Account → Two-factor.** An ordinary TOTP secret — any authenticator
+app reads the QR code. Once it is on, the password alone is not enough.
+
+Recovery codes are shown once, when you turn it on. They are the way back if the
+phone is gone, and they are not shown again.
+
+## A passkey
+
+**Settings → Account → Passkeys → Add a passkey.**
+
+A key on a device instead of a secret in your head. The private half never leaves
+the device — a phone's secure element, a laptop's keychain, a hardware key — and
+the signature is bound to the address it was made for, so a convincing copy of the
+sign-in page at a different address gets nothing.
+
+Give each one a name you will recognise later. *min bærbare* is what makes a list
+of keys reviewable, and a list nobody can read is a list nobody revokes from.
+
+Passkeys need the address in `VERDANDE_BASE_URL` to be a hostname. Browsers refuse
+to make one for a bare IP address, so an instance reached at `http://192.168.1.10:8080`
+will show the passkey section as unavailable rather than failing at the moment
+somebody tries.
+
+!!! note "One is enough, two is better"
+    Lose the only device holding your only passkey and you are back to the
+    password. Keep the password, or register a second key — a phone as well as a
+    laptop.

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

@@ -301,7 +301,11 @@ 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 +372,9 @@ 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 +903,65 @@ 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/calendar_handlers.go

@@ -0,0 +1,548 @@
+package httpapi
+
+import (
+	"context"
+	"errors"
+	"net/http"
+	"time"
+
+	"github.com/kristianwind/verdande/internal/gcal"
+	"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"`
+}
+
+func (s *Server) handleGetCalendar(w http.ResponseWriter, r *http.Request) {
+	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 == "" {
+		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
+	}
+	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) {
+	account, err := s.db.CalendarAccountFor(ctx, user.ID, calendarProviderName)
+	if err != nil {
+		return 0, err
+	}
+	if account == nil || account.RefreshToken == "" {
+		return 0, 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())
+	written := 0
+	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
+}

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

@@ -58,6 +58,16 @@ const (
 	// read "something went wrong", and had nowhere to go. The interface wraps the
 	// message in one that says where it came from.
 	CodeGmailFailed = "gmail_failed"
+
+	// And the same for a mailbox read over IMAP. A host's refusal is the whole
+	// 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
@@ -179,15 +177,27 @@ func (s *Server) handleGmailCallback(w http.ResponseWriter, r *http.Request) {
 	delete(settings, "pkce_state")
 	delete(settings, "pkce_expires")
 
-	settings["refresh_token"] = token.RefreshToken
-	settings["access_token"] = token.AccessToken
-	settings["expires_at"] = token.ExpiresAt.Unix()
-	settings["email"] = email
-	if _, ok := settings["trigger"]; !ok {
-		settings["trigger"] = "starred"
+	if err := s.db.SetUserSettings(r.Context(), user.ID, "gmail", settings); err != nil {
+		s.internal(w, r, "clear gmail handshake", err)
+		return
 	}
 
-	if err := s.db.SetUserSettings(r.Context(), user.ID, "gmail", settings); err != nil {
+	// The mailbox itself, kept beside the ones read over IMAP. Connecting again
+	// writes the same row: Gmail is one per person, because the OAuth flow is.
+	box, err := s.db.MailboxOfKind(r.Context(), user.ID, "gmail")
+	if err != nil {
+		s.internal(w, r, "read gmail mailbox", err)
+		return
+	}
+	if box == nil {
+		box = &store.Mailbox{UserID: user.ID, Kind: "gmail", Trigger: "starred"}
+	}
+	box.Name = email
+	box.Username = email
+	box.RefreshToken = token.RefreshToken
+	box.AccessToken = token.AccessToken
+	box.ExpiresAt = token.ExpiresAt
+	if err := s.db.SaveMailbox(r.Context(), box); err != nil {
 		s.internal(w, r, "save gmail tokens", err)
 		return
 	}
@@ -239,37 +249,52 @@ 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) {
-	settings, err := s.db.UserSettings(ctx, user.ID, "gmail")
+	box, err := s.db.MailboxOfKind(ctx, user.ID, "gmail")
 	if err != nil {
 		return 0, err
 	}
-	str := func(key string) string {
-		v, _ := settings[key].(string)
-		return v
+	if box != nil {
+		// 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.lockSync(box.ID)
+		defer unlock()
+		if fresh, err := s.db.MailboxOfKind(ctx, user.ID, "gmail"); err == nil && fresh != nil {
+			box = fresh
+		}
 	}
-
-	refresh := str("refresh_token")
-	if refresh == "" {
+	if box == nil || box.RefreshToken == "" {
 		return 0, nil // not connected; nothing to do and nothing to complain about
 	}
-	query := gmail.Query(str("trigger"), str("label"))
+	query := gmail.Query(box.Trigger, box.Label)
 	if query == "" {
 		return 0, nil // connected but no trigger chosen
 	}
+	refresh := box.RefreshToken
 
 	// The access token is refreshed only when it has actually expired.
-	access := str("access_token")
-	expires, _ := settings["expires_at"].(float64)
-	if access == "" || int64(expires) <= time.Now().Unix() {
+	access := box.AccessToken
+	if access == "" || box.ExpiresAt.Before(time.Now()) {
 		token, err := s.gmailConfig(ctx).Refresh(ctx, refresh)
 		if err != nil {
 			return 0, err
 		}
 		access = token.AccessToken
-		settings["access_token"] = access
-		settings["expires_at"] = token.ExpiresAt.Unix()
-		if err := s.db.SetUserSettings(ctx, user.ID, "gmail", settings); err != nil {
+		box.AccessToken = access
+		box.ExpiresAt = token.ExpiresAt
+		if err := s.db.SaveMailbox(ctx, box); err != nil {
 			return 0, err
 		}
 	}
@@ -281,7 +306,7 @@ func (s *Server) SyncGmail(ctx context.Context, user *store.User) (int, error) {
 			// The person revoked access, or changed their password. Forget the
 			// tokens rather than retrying every ten minutes forever.
 			s.log.Info("gmail access was revoked; disconnecting", "user", user.ID)
-			_ = s.db.SetUserSettings(ctx, user.ID, "gmail", map[string]any{})
+			_ = s.db.DeleteMailbox(ctx, user.ID, box.ID)
 		}
 		return 0, err
 	}
@@ -290,19 +315,15 @@ func (s *Server) SyncGmail(ctx context.Context, user *store.User) (int, error) {
 	// rather than as a table: it is bounded by the query's own 30-day window, and
 	// a table would be one more thing to migrate for a feature this small.
 	seen := map[string]bool{}
-	if raw, ok := settings["seen"].([]any); ok {
-		for _, v := range raw {
-			if id, ok := v.(string); ok {
-				seen[id] = true
-			}
-		}
+	for _, id := range box.Seen {
+		seen[id] = true
 	}
 
 	inbox, err := s.db.InboxID(ctx, user.ID)
 	if err != nil {
 		return 0, err
 	}
-	projectID := str("project_id")
+	projectID := box.ProjectID
 	if projectID == "" {
 		projectID = inbox
 	} else if _, err := store.RequireProjectRole(ctx, s.db, projectID, user.ID, store.RoleEditor); err != nil {
@@ -350,17 +371,38 @@ 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([]any, 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
 			}
 		}
-		settings["seen"] = keep
-		settings["last_sync"] = time.Now().Unix()
-		if err := s.db.SetUserSettings(ctx, user.ID, "gmail", settings); err != nil {
+		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 {
 			return created, err
 		}
 	}
@@ -483,30 +525,25 @@ func (s *Server) handleSetGmailClient(w http.ResponseWriter, r *http.Request) {
 // natural place to learn the address, and it is also the one moment that cannot be
 // retried — so the status endpoint asks again when it finds nothing, and the answer
 // corrects itself on the next look.
-func (s *Server) gmailProfile(ctx context.Context, user *store.User, settings map[string]any) (string, error) {
-	str := func(key string) string {
-		v, _ := settings[key].(string)
-		return v
-	}
-
-	access := str("access_token")
-	expires, _ := settings["expires_at"].(float64)
-	if access == "" || int64(expires) <= time.Now().Unix() {
-		token, err := s.gmailConfig(ctx).Refresh(ctx, str("refresh_token"))
+func (s *Server) gmailProfile(ctx context.Context, box *store.Mailbox) (string, error) {
+	access := box.AccessToken
+	if access == "" || box.ExpiresAt.Before(time.Now()) {
+		token, err := s.gmailConfig(ctx).Refresh(ctx, box.RefreshToken)
 		if err != nil {
 			return "", err
 		}
 		access = token.AccessToken
-		settings["access_token"] = access
-		settings["expires_at"] = token.ExpiresAt.Unix()
+		box.AccessToken = access
+		box.ExpiresAt = token.ExpiresAt
 	}
 
 	email, err := s.gmailClient(access).Profile(ctx)
 	if err != nil {
 		return "", err
 	}
-	settings["email"] = email
-	if err := s.db.SetUserSettings(ctx, user.ID, "gmail", settings); err != nil {
+	box.Name = email
+	box.Username = email
+	if err := s.db.SaveMailbox(ctx, box); err != nil {
 		return "", err
 	}
 	return email, nil

internal/httpapi/gmail_test.go

@@ -1,6 +1,7 @@
 package httpapi
 
 import (
+	"github.com/kristianwind/verdande/internal/store"
 	"net/http"
 	"net/http/httptest"
 	"net/url"
@@ -28,7 +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)
@@ -38,8 +39,8 @@ func TestAGmailFailureSaysWhatGmailSaidAndIsRecorded(t *testing.T) {
 		t.Fatal(err)
 	}
 	// Connected, with a refresh token that will be refused.
-	if err := ts.db.SetUserSettings(t.Context(), user.ID, "gmail", map[string]any{
-		"refresh_token": "spent", "trigger": "starred",
+	if err := ts.db.SaveMailbox(t.Context(), &store.Mailbox{
+		UserID: user.ID, Kind: "gmail", RefreshToken: "spent", Trigger: "starred",
 	}); err != nil {
 		t.Fatal(err)
 	}
@@ -96,7 +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
@@ -111,9 +112,9 @@ func TestASlowMailboxDoesNotHangTheRequest(t *testing.T) {
 	}
 	// A token that has not expired, so the run goes straight to the message list
 	// rather than stopping at a refresh.
-	if err := ts.db.SetUserSettings(t.Context(), user.ID, "gmail", map[string]any{
-		"refresh_token": "r", "access_token": "a", "trigger": "starred",
-		"expires_at": time.Now().Add(time.Hour).Unix(),
+	if err := ts.db.SaveMailbox(t.Context(), &store.Mailbox{
+		UserID: user.ID, Kind: "gmail", RefreshToken: "r", AccessToken: "a",
+		Trigger: "starred", ExpiresAt: time.Now().Add(time.Hour),
 	}); err != nil {
 		t.Fatal(err)
 	}

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)
@@ -370,27 +389,28 @@ type gmailSettings struct {
 }
 
 func (s *Server) handleGetGmail(w http.ResponseWriter, r *http.Request) {
-	values, err := s.db.UserSettings(r.Context(), userFrom(r.Context()).ID, "gmail")
+	user := userFrom(r.Context())
+	box, err := s.db.MailboxOfKind(r.Context(), user.ID, "gmail")
 	if err != nil {
-		s.internal(w, r, "gmail settings", err)
+		s.internal(w, r, "gmail mailbox", err)
 		return
 	}
-	str := func(key string) string {
-		v, _ := values[key].(string)
-		return v
+	if box == nil {
+		writeJSON(w, http.StatusOK, gmailSettings{})
+		return
 	}
+
 	// The mailbox address, fetched again if it is missing.
 	//
-	// It is stored at connect time, and the call that fetches it can fail — a
-	// slow token, a scope Google had not applied yet. That failure used to be a
-	// log line and an empty string, so the page said "an unknown account" and went
-	// on saying it forever: the only way back was to disconnect and reconnect,
-	// which nobody would guess. Asking again here costs one request on a page
-	// nobody opens often, and it means the wrong answer lasts until the next look
-	// rather than until somebody reconnects.
-	email := str("email")
-	if email == "" && str("refresh_token") != "" {
-		if fetched, err := s.gmailProfile(r.Context(), userFrom(r.Context()), values); err == nil {
+	// It is stored at connect time, and the call that fetches it can fail — a slow
+	// token, a scope Google had not applied yet. That failure used to be a log line
+	// and an empty string, so the page said "an unknown account" and went on saying
+	// it forever: the only way back was to disconnect and reconnect, which nobody
+	// would guess. Asking again here costs one request on a page nobody opens
+	// often, and it means the wrong answer lasts until the next look.
+	email := box.Username
+	if email == "" && box.RefreshToken != "" {
+		if fetched, err := s.gmailProfile(r.Context(), box); err == nil {
 			email = fetched
 		} else {
 			s.log.Warn("gmail profile", "err", err)
@@ -398,10 +418,10 @@ func (s *Server) handleGetGmail(w http.ResponseWriter, r *http.Request) {
 	}
 
 	writeJSON(w, http.StatusOK, gmailSettings{
-		Connected: str("refresh_token") != "",
+		Connected: box.RefreshToken != "",
 		Email:     email,
-		Trigger:   str("trigger"),
-		Label:     str("label"),
+		Trigger:   box.Trigger,
+		Label:     box.Label,
 	})
 }
 
@@ -412,27 +432,42 @@ func (s *Server) handleSetGmail(w http.ResponseWriter, r *http.Request) {
 	}
 	user := userFrom(r.Context())
 
-	values, err := s.db.UserSettings(r.Context(), user.ID, "gmail")
+	box, err := s.db.MailboxOfKind(r.Context(), user.ID, "gmail")
 	if err != nil {
-		s.internal(w, r, "gmail settings", err)
+		s.internal(w, r, "gmail mailbox", err)
 		return
 	}
-	values["trigger"] = req.Trigger
-	values["label"] = req.Label
+	if box == nil {
+		// Choosing what makes a task before connecting is allowed, and the choice is
+		// kept: the row is the mailbox with no credential in it yet, which reads as
+		// not connected everywhere that asks and is skipped by the sweep.
+		box = &store.Mailbox{UserID: user.ID, Kind: "gmail"}
+	}
+	box.Trigger = req.Trigger
+	box.Label = req.Label
 
-	if err := s.db.SetUserSettings(r.Context(), user.ID, "gmail", values); err != nil {
+	if err := s.db.SaveMailbox(r.Context(), box); err != nil {
 		s.internal(w, r, "save gmail settings", err)
 		return
 	}
 	w.WriteHeader(http.StatusNoContent)
 }
 
-// handleDisconnectGmail forgets the connection, tokens and all.
+// handleDisconnectGmail forgets the connection, tokens and all. The tasks it made
+// stay: they are the person's work now, not the mailbox's.
 func (s *Server) handleDisconnectGmail(w http.ResponseWriter, r *http.Request) {
-	if err := s.db.SetUserSettings(r.Context(), userFrom(r.Context()).ID, "gmail", map[string]any{}); err != nil {
-		s.internal(w, r, "disconnect gmail", err)
+	user := userFrom(r.Context())
+	box, err := s.db.MailboxOfKind(r.Context(), user.ID, "gmail")
+	if err != nil {
+		s.internal(w, r, "gmail mailbox", err)
 		return
 	}
+	if box != nil {
+		if err := s.db.DeleteMailbox(r.Context(), user.ID, box.ID); err != nil {
+			s.internal(w, r, "disconnect gmail", err)
+			return
+		}
+	}
 	w.WriteHeader(http.StatusNoContent)
 }
 

internal/httpapi/mailbox_handlers.go

@@ -0,0 +1,265 @@
+package httpapi
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"net/http"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/go-chi/chi/v5"
+	"github.com/kristianwind/verdande/internal/imap"
+	"github.com/kristianwind/verdande/internal/store"
+)
+
+// defaultMailboxSyncBudget bounds one read of one mailbox when somebody is waiting.
+// The same reasoning as Gmail's: a mailbox that has stopped answering must not
+// hold a request open until whatever sits in front of this server answers for it.
+const defaultMailboxSyncBudget = 25 * time.Second
+
+func (s *Server) handleListMailboxes(w http.ResponseWriter, r *http.Request) {
+	user := userFrom(r.Context())
+	list, err := s.db.Mailboxes(r.Context(), user.ID)
+	if err != nil {
+		s.internal(w, r, "list mailboxes", err)
+		return
+	}
+	if list == nil {
+		list = []store.Mailbox{}
+	}
+	writeJSON(w, http.StatusOK, map[string]any{"mailboxes": list})
+}
+
+// handleAddMailbox connects one, after proving it can actually be read.
+//
+// Tested before it is saved, not after: a mailbox that was accepted and then
+// silently fails every ten minutes is worse than one that refused at the door,
+// where the person is still holding the password they just typed.
+func (s *Server) handleAddMailbox(w http.ResponseWriter, r *http.Request) {
+	var body struct {
+		Name     string `json:"name"`
+		Host     string `json:"host"`
+		Username string `json:"username"`
+		Password string `json:"password"`
+		Folder   string `json:"folder"`
+	}
+	if err := decodeJSON(w, r, &body); err != nil {
+		return
+	}
+
+	body.Host = strings.TrimSpace(body.Host)
+	body.Username = strings.TrimSpace(body.Username)
+	if body.Host == "" || body.Username == "" || body.Password == "" {
+		writeError(w, http.StatusBadRequest, CodeValidation,
+			"a mailbox needs a host, a username and a password")
+		return
+	}
+	// A host with no port is the mistake everyone makes once, and 993 is the answer
+	// for every host worth naming.
+	if !strings.Contains(body.Host, ":") {
+		body.Host += ":993"
+	}
+
+	account := imap.Account{
+		Host: body.Host, Username: body.Username,
+		Password: body.Password, Folder: body.Folder,
+	}
+	client, err := imap.Dial(account)
+	if err != nil {
+		s.upstream(w, r, CodeMailboxFailed, "connect mailbox", err)
+		return
+	}
+	client.Close()
+
+	user := userFrom(r.Context())
+	m := &store.Mailbox{
+		UserID: user.ID, Kind: "imap", Name: strings.TrimSpace(body.Name),
+		Host: body.Host, Username: body.Username,
+		Password: body.Password, Folder: body.Folder,
+	}
+	if m.Name == "" {
+		m.Name = body.Username
+	}
+	if err := s.db.SaveMailbox(r.Context(), m); err != nil {
+		// The unique index. Saying which mailbox is already here beats "constraint
+		// failed", which is true and useless.
+		if strings.Contains(err.Error(), "UNIQUE") {
+			writeError(w, http.StatusConflict, CodeValidation,
+				fmt.Sprintf("%s on %s is already connected", body.Username, body.Host))
+			return
+		}
+		s.internal(w, r, "save mailbox", err)
+		return
+	}
+	writeJSON(w, http.StatusCreated, m)
+}
+
+func (s *Server) handleDeleteMailbox(w http.ResponseWriter, r *http.Request) {
+	user := userFrom(r.Context())
+	if err := s.db.DeleteMailbox(r.Context(), user.ID, chi.URLParam(r, "mailboxID")); err != nil {
+		s.internal(w, r, "delete mailbox", err)
+		return
+	}
+	w.WriteHeader(http.StatusNoContent)
+}
+
+// handleSyncMailbox reads one mailbox now, within a budget of its own.
+func (s *Server) handleSyncMailbox(w http.ResponseWriter, r *http.Request) {
+	user := userFrom(r.Context())
+	m, err := s.db.Mailbox(r.Context(), user.ID, chi.URLParam(r, "mailboxID"))
+	if err != nil {
+		s.internal(w, r, "read mailbox", err)
+		return
+	}
+	if m == nil {
+		writeError(w, http.StatusNotFound, CodeNotFound, "no such mailbox")
+		return
+	}
+
+	ctx, cancel := context.WithTimeout(r.Context(), defaultMailboxSyncBudget)
+	defer cancel()
+
+	created, err := s.SyncMailbox(ctx, user, m)
+	if err != nil {
+		// Whatever was made by the deadline is kept: each task is committed as it
+		// is made, so a short budget is a shorter run rather than a lost one.
+		if errors.Is(err, context.DeadlineExceeded) {
+			writeJSON(w, http.StatusOK, map[string]any{"created": created, "partial": true})
+			return
+		}
+		s.upstream(w, r, CodeMailboxFailed, "sync mailbox", err)
+		return
+	}
+	writeJSON(w, http.StatusOK, map[string]any{"created": created})
+}
+
+// SyncMailbox turns the flagged mail newer than the last run into tasks.
+//
+// Exported because the background job calls it too, on the same terms and without
+// a budget: nobody is waiting there.
+func (s *Server) SyncMailbox(ctx context.Context, user *store.User, m *store.Mailbox) (int, error) {
+	// 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.lockSync(m.ID)
+	defer unlock()
+
+	// Re-read under the lock. The row that came in may have been fetched before the
+	// run that just finished moved the marker.
+	if fresh, err := s.db.Mailbox(ctx, m.UserID, m.ID); err == nil && fresh != nil {
+		m = fresh
+	}
+
+	client, err := imap.Dial(imap.Account{
+		Host: m.Host, Username: m.Username, Password: m.Password, Folder: m.Folder,
+	})
+	if err != nil {
+		return 0, err
+	}
+	defer client.Close()
+
+	messages, searched, err := client.Since(m.LastUID, 25)
+	if err != nil {
+		return 0, err
+	}
+	if len(messages) == 0 {
+		return 0, nil
+	}
+
+	projectID, err := s.db.InboxID(ctx, user.ID)
+	if err != nil {
+		return 0, err
+	}
+
+	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
+			// below has to be written for it: a run that created tasks and forgot how
+			// far it got would make them all again on the next pass.
+			break
+		}
+
+		subject := msg.Subject
+		if subject == "" {
+			subject = "(uden emne)"
+		}
+		content := subject
+		if msg.From != "" {
+			content = msg.From + ": " + subject
+		}
+
+		task := &store.Task{
+			ProjectID:   projectID,
+			Content:     content,
+			Description: msg.Snippet,
+			Priority:    4,
+			CreatedBy:   user.ID,
+		}
+		if err := s.db.CreateTask(ctx, task, nil); err != nil {
+			s.log.Warn("mailbox create task", "err", err, "mailbox", m.ID)
+			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
+	// server did not put a uid in the fetch reply.
+	if ctx.Err() == nil && searched > highest {
+		highest = searched
+	}
+
+	// Written even when the loop was cut short, and outside the request's context
+	// so a cancelled request still records what it did.
+	if highest > m.LastUID {
+		if err := s.db.MarkMailboxRead(context.WithoutCancel(ctx), m.ID, highest, time.Now()); err != nil {
+			s.log.Warn("mark mailbox read", "err", err, "mailbox", m.ID)
+		}
+	}
+	if ctx.Err() != nil {
+		return created, ctx.Err()
+	}
+	return created, nil
+}
+
+// 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()
+	return mu.Unlock
+}

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

@@ -2,11 +2,13 @@ package httpapi
 
 import (
 	"net/http"
+	"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"
 )
 
@@ -98,6 +100,12 @@ func (s *Server) notifyProject(r *http.Request, projectID, taskID, actorID, kind
 	}
 }
 
+// PushToUser is pushToUser for callers outside this package — the reminder job,
+// which has the schedule but not the keys.
+func (s *Server) PushToUser(userID, title, body, projectID string) {
+	s.pushToUser(userID, title, body, projectID)
+}
+
 func (s *Server) pushToUser(userID, title, body, projectID string) {
 	ctx, cancel := contextWithBackgroundTimeout(30 * time.Second)
 	defer cancel()
@@ -164,6 +172,23 @@ 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,
@@ -183,7 +208,10 @@ 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_handlers.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"fmt"
 	"net/http"
+	"strings"
 	"time"
 )
 
@@ -72,13 +73,26 @@ func (s *Server) handleRestartFromPanel(w http.ResponseWriter, r *http.Request)
 	ctx, cancel := context.WithTimeout(context.WithoutCancel(r.Context()), 10*time.Second)
 	defer cancel()
 
-	url := fmt.Sprintf("%s/api/servers/%s/restart", s.cfg.PanelURL, s.cfg.PanelServerID)
-	req, err := http.NewRequestWithContext(ctx, http.MethodPost, url, nil)
+	// safe-restart rather than restart, and the difference is not politeness.
+	//
+	// The plain endpoint does its work while the request is open: it stops the
+	// container — which kills this process — and the panel, seeing the caller
+	// vanish, never gets to the starting half. That took production down and left
+	// it down for four minutes on 18 August, and it cannot be fixed from this side:
+	// any button that synchronously asks for its own death has the same shape.
+	//
+	// safe-restart is scheduled. The panel answers "Restart scheduled" and does the
+	// work on its own afterwards, so nothing depends on this process still being
+	// alive to hear the reply.
+	url := fmt.Sprintf("%s/api/servers/%s/safe-restart", s.cfg.PanelURL, s.cfg.PanelServerID)
+	body := strings.NewReader(`{"backup_first":false,"target_id":""}`)
+	req, err := http.NewRequestWithContext(ctx, http.MethodPost, url, body)
 	if err != nil {
 		s.internal(w, r, "build panel request", err)
 		return
 	}
 	req.Header.Set("Authorization", "Bearer "+s.cfg.PanelToken)
+	req.Header.Set("Content-Type", "application/json")
 
 	resp, err := (&http.Client{Timeout: 10 * time.Second}).Do(req)
 	if err != nil {

internal/httpapi/panel_test.go

@@ -1,9 +1,11 @@
 package httpapi
 
 import (
+	"io"
 	"net/http"
 	"net/http/httptest"
 	"strings"
+	"sync"
 	"testing"
 	"time"
 
@@ -15,6 +17,11 @@ import (
 // request has to end either way, or whatever sits in front answers for it.
 func TestAPanelThatNeverAnswersStillEndsTheRequest(t *testing.T) {
 	panel := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		// Drained first. A real server reads what it was sent, and one that does not
+		// never learns the caller has hung up — httptest.Server.Close then waits for
+		// a handler that will never return, and the whole binary times out instead
+		// of the one request.
+		_, _ = io.Copy(io.Discard, r.Body)
 		<-r.Context().Done()
 	}))
 	defer panel.Close()
@@ -56,6 +63,7 @@ func TestAPanelThatNeverAnswersStillEndsTheRequest(t *testing.T) {
 // And a panel that says no must say so in this server's own words, not in a proxy's.
 func TestAPanelThatRefusesSaysSoAsJSON(t *testing.T) {
 	panel := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		_, _ = io.Copy(io.Discard, r.Body)
 		w.WriteHeader(http.StatusForbidden)
 	}))
 	defer panel.Close()
@@ -75,3 +83,69 @@ func TestAPanelThatRefusesSaysSoAsJSON(t *testing.T) {
 		t.Errorf("the reply does not say what the panel answered: %v", body)
 	}
 }
+
+// Forty copies of one mail arrived in a single second because two runs read the
+// same marker before either wrote a new one — somebody pressing "Fetch now" while
+// the ten-minute sweep was already inside the same mailbox.
+//
+// The lock is what stops it, and a lock is only worth having if something tries
+// the door: this runs the two concurrently on purpose.
+func TestTwoRunsOfOneMailboxDoNotOverlap(t *testing.T) {
+	// A bare server: the lock needs nothing but its own zero value, and building a
+	// database and a session around it would only make the test slower to read.
+	srv := &Server{}
+
+	var inside, most int
+	var mu sync.Mutex
+	release := make(chan struct{})
+
+	// 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.lockSync("box-1")
+		mu.Lock()
+		inside++
+		if inside > most {
+			most = inside
+		}
+		mu.Unlock()
+
+		<-release
+
+		mu.Lock()
+		inside--
+		mu.Unlock()
+		unlock()
+		done <- struct{}{}
+	}
+
+	first, second := make(chan struct{}), make(chan struct{})
+	go run(first)
+	go run(second)
+
+	// Long enough that both would be inside if nothing kept them apart.
+	time.Sleep(100 * time.Millisecond)
+	close(release)
+	<-first
+	<-second
+
+	if most != 1 {
+		t.Errorf("%d runs were inside the same mailbox at once; that is how one mail "+
+			"becomes forty tasks", most)
+	}
+
+	// And two different mailboxes must not wait for each other: one slow host is
+	// not everybody's problem.
+	a := srv.lockSync("box-a")
+	done := make(chan struct{})
+	go func() {
+		srv.lockSync("box-b")()
+		close(done)
+	}()
+	select {
+	case <-done:
+	case <-time.After(2 * time.Second):
+		t.Error("a second mailbox waited for the first")
+	}
+	a()
+}

internal/httpapi/projects_handlers.go

@@ -23,6 +23,7 @@ type projectJSON struct {
 	SortOrder   float64 `json:"sort_order"`
 	Role        string  `json:"role"`
 	MemberCount int     `json:"member_count"`
+	OpenCount   int     `json:"open_count"`
 	Shared      bool    `json:"shared"`
 	// GroupID is the sidebar group the asking user has filed it under, empty for
 	// none. Always empty on a project shared with them: grouping is a column on
@@ -34,7 +35,7 @@ func toProjectJSON(p store.Project) projectJSON {
 	return projectJSON{
 		ID: p.ID, Name: p.Name, Color: p.Color, Icon: p.Icon, ViewMode: p.ViewMode,
 		OwnerID: p.OwnerID, IsInbox: p.IsInbox, Archived: p.Archived,
-		SortOrder: p.SortOrder, Role: string(p.Role), MemberCount: p.MemberCount,
+		SortOrder: p.SortOrder, Role: string(p.Role), MemberCount: p.MemberCount, OpenCount: p.OpenCount,
 		Shared: p.MemberCount > 1, GroupID: p.GroupID,
 	}
 }

internal/httpapi/server.go

@@ -11,6 +11,7 @@ import (
 	"os"
 	"path"
 	"strings"
+	"sync"
 	"time"
 
 	"github.com/go-chi/chi/v5"
@@ -40,6 +41,18 @@ type Server struct {
 	mcp     *mcp.Server
 	updates *update.Checker
 
+	// syncing serialises reads of one mailbox against itself. Two runs at once —
+	// somebody pressing "Fetch now" while the ten-minute sweep is in the middle of
+	// the same mailbox — both start from the marker as it was, both fetch the same
+	// messages, and both make tasks out of them. That is how forty copies of one
+	// mail arrived in a single second.
+	//
+	// A map of mutexes rather than one lock: two people's mailboxes have nothing to
+	// say to each other, and a single lock would make one slow host everybody's
+	// problem. Never cleaned out, because the key is a mailbox id and there are as
+	// many of those as there are mailboxes.
+	syncing sync.Map
+
 	// Nil when the base URL is not something an authenticator will accept — a bare
 	// hostname with no scheme, say. The endpoints answer 503 rather than the
 	// process refusing to start: passkeys are one way in among three, and an
@@ -51,6 +64,11 @@ type Server struct {
 	// than the rest of the API.
 	loginLimiter *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
@@ -68,6 +86,10 @@ func New(cfg *config.Config, db *store.DB, log *slog.Logger, web fs.FS) *Server
 		hub:          realtime.NewHub(log),
 		loginLimiter: newLimiter(10, 15*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 {
@@ -120,6 +142,12 @@ 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)
 
@@ -130,6 +158,19 @@ 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)
@@ -165,13 +206,10 @@ 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
@@ -181,6 +219,23 @@ 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.
@@ -260,6 +315,36 @@ func New(cfg *config.Config, db *store.DB, log *slog.Logger, web fs.FS) *Server
 
 			r.Get("/version", s.handleVersion)
 
+			// 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)
+				r.Delete("/{mailboxID}", s.handleDeleteMailbox)
+				r.Post("/{mailboxID}/sync", s.handleSyncMailbox)
+			})
+
 			r.Route("/gmail", func(r chi.Router) {
 				r.Get("/", s.handleGetGmail)
 				r.Put("/", s.handleSetGmail)
@@ -279,12 +364,26 @@ 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)
+			})
+
 			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)
 
@@ -352,6 +451,11 @@ 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/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/imap/imap.go

@@ -16,14 +16,18 @@
 package imap
 
 import (
+	"bytes"
 	"crypto/tls"
+	"crypto/x509"
 	"fmt"
+	"io"
 	"net"
 	"strings"
 	"time"
 
 	"github.com/emersion/go-imap/v2"
 	"github.com/emersion/go-imap/v2/imapclient"
+	"github.com/emersion/go-message"
 )
 
 // Message is one mail, reduced to what a task needs.
@@ -41,6 +45,13 @@ type Account struct {
 	Username string
 	Password string // an app-specific password on every host worth naming
 	Folder   string // "INBOX" when empty
+
+	// RootCAs adds a certificate authority to trust, on top of the system's. It
+	// exists so a test can put a real IMAP server behind a self-signed certificate
+	// and still be refused by everything else — the field can only widen trust,
+	// never switch verification off, which is the difference between a seam and a
+	// hole. Nil in production, where the system's roots are the answer.
+	RootCAs *x509.CertPool
 }
 
 // Dial opens a TLS connection and logs in. The caller closes it.
@@ -55,7 +66,11 @@ func Dial(a Account) (*Client, error) {
 	}
 
 	c, err := imapclient.DialTLS(a.Host, &imapclient.Options{
-		TLSConfig: &tls.Config{ServerName: host, MinVersion: tls.VersionTLS12},
+		TLSConfig: &tls.Config{
+			ServerName: host,
+			MinVersion: tls.VersionTLS12,
+			RootCAs:    a.RootCAs,
+		},
 	})
 	if err != nil {
 		return nil, fmt.Errorf("connect to %s: %w", a.Host, err)
@@ -96,9 +111,13 @@ func (c *Client) Close() error {
 // that consumed it would be taking something away. Flagging a mail is a deliberate
 // act with no other meaning, which is exactly what is wanted — the same reason the
 // Gmail side reads stars.
-func (c *Client) Since(uid uint32, limit int) ([]Message, error) {
+// The second return is the highest uid the search considered. A caller that got
+// through every message can move its marker to that, and then it does not matter
+// whether the server put a uid in each fetch reply — which some do not, and which
+// is how the same mail became a task again on every run.
+func (c *Client) Since(uid uint32, limit int) ([]Message, uint32, error) {
 	if _, err := c.c.Select(c.folder, &imap.SelectOptions{ReadOnly: true}).Wait(); err != nil {
-		return nil, fmt.Errorf("open %s: %w", c.folder, err)
+		return nil, 0, fmt.Errorf("open %s: %w", c.folder, err)
 	}
 
 	// From uid+1 to the end. A mailbox with nothing new answers with no uids
@@ -112,12 +131,27 @@ func (c *Client) Since(uid uint32, limit int) ([]Message, error) {
 	}
 	found, err := c.c.UIDSearch(criteria, nil).Wait()
 	if err != nil {
-		return nil, fmt.Errorf("search %s: %w", c.folder, err)
+		return nil, 0, fmt.Errorf("search %s: %w", c.folder, err)
 	}
 
 	uids := found.AllUIDs()
+
+	// Anything at or below the marker is dropped here rather than trusted to the
+	// range in the query. A server that reads `1272:*` as `0:1272` — and one does,
+	// which is how the same mail became a task every ten minutes with the marker
+	// standing still at 1271 — hands back the whole mailbox. The marker is ours;
+	// enforcing it here costs one pass over a list of at most a few hundred
+	// numbers and does not depend on anybody else's reading of the spec.
+	kept := make([]imap.UID, 0, len(uids))
+	for _, u := range uids {
+		if uint32(u) > uid {
+			kept = append(kept, u)
+		}
+	}
+	uids = kept
+
 	if len(uids) == 0 {
-		return nil, nil
+		return nil, uid, nil
 	}
 	if limit > 0 && len(uids) > limit {
 		// The newest ones. A mailbox flagged over years would otherwise make the
@@ -127,29 +161,51 @@ func (c *Client) Since(uid uint32, limit int) ([]Message, error) {
 
 	want := imap.UIDSetNum(uids...)
 	fetch := &imap.FetchOptions{
-		Envelope:    true,
-		UID:         true,
-		BodySection: []*imap.FetchItemBodySection{{Specifier: imap.PartSpecifierText, Peek: true}},
+		Envelope: true,
+		UID:      true,
+		// The whole message, headers included, so the MIME structure can be walked.
+		// TEXT alone gives the body as bytes — boundaries and part headers and all —
+		// which is what put "--=_be71cb39… Content-Transfer-Encoding: 8bit" at the
+		// front of every task made from a multipart mail.
+		BodySection: []*imap.FetchItemBodySection{{Peek: true}},
 	}
+	var highest uint32
+	for _, u := range uids {
+		if uint32(u) > highest {
+			highest = uint32(u)
+		}
+	}
+
 	msgs, err := c.c.Fetch(want, fetch).Collect()
 	if err != nil {
-		return nil, fmt.Errorf("fetch from %s: %w", c.folder, err)
+		return nil, 0, fmt.Errorf("fetch from %s: %w", c.folder, err)
 	}
 
 	out := make([]Message, 0, len(msgs))
-	for _, m := range msgs {
+	for i, m := range msgs {
 		if m.Envelope == nil {
 			continue
 		}
+
+		// The uid comes from the search when the fetch reply does not carry one.
+		// A missing uid is not cosmetic: it is the marker the next run starts from,
+		// and a marker stuck at zero makes every message arrive again on every run.
+		// That is what happened against a real server while the tests stayed green,
+		// because the server they run against always answers with it.
+		msgUID := uint32(m.UID)
+		if msgUID == 0 && i < len(uids) {
+			msgUID = uint32(uids[i])
+		}
+
 		out = append(out, Message{
-			UID:     uint32(m.UID),
+			UID:     msgUID,
 			From:    address(m.Envelope.From),
 			Subject: strings.TrimSpace(m.Envelope.Subject),
 			Snippet: snippet(m),
 			Date:    m.Envelope.Date,
 		})
 	}
-	return out, nil
+	return out, highest, nil
 }
 
 // address renders the first sender as "Name <addr>", or just the address.
@@ -165,23 +221,150 @@ func address(list []imap.Address) string {
 	return a.Name + " <" + addr + ">"
 }
 
-// snippet is the first readable line or so of the body.
+// snippet is the first readable text in the mail.
 //
-// No MIME walk and no HTML stripping yet: this is what shows under a task's title,
-// and a wrong-but-short line is a smaller problem than a parser that has to be
-// right about every mail ever sent. The full mail stays where it is.
+// It walks the MIME structure rather than taking the body as bytes. text/plain is
+// preferred and HTML is the fallback with its tags stripped — crudely, because
+// this is the line under a task's title and not a rendering engine. The mail
+// itself stays where it is.
 const snippetLimit = 400
 
 func snippet(m *imapclient.FetchMessageBuffer) string {
 	for _, body := range m.BodySection {
-		text := strings.TrimSpace(string(body.Bytes))
-		if text == "" {
-			continue
+		if text := readable(body.Bytes); text != "" {
+			return cut(text)
 		}
-		if len(text) > snippetLimit {
-			text = text[:snippetLimit] + "…"
-		}
-		return text
 	}
 	return ""
 }
+
+func readable(raw []byte) string {
+	entity, err := message.Read(bytes.NewReader(raw))
+	if err != nil {
+		// Not something this parser recognises. The raw bytes read badly but read,
+		// and a mail is not worth losing over its own headers.
+		return strings.TrimSpace(string(raw))
+	}
+	return strings.TrimSpace(fromEntity(entity, 0))
+}
+
+// fromEntity descends into a multipart mail. The depth guard is for the mail that
+// nests parts inside parts inside parts — rare, and cheaper to bound than to trust.
+func fromEntity(entity *message.Entity, depth int) string {
+	if depth > 4 {
+		return ""
+	}
+
+	if parts := entity.MultipartReader(); parts != nil {
+		var html string
+		for {
+			part, err := parts.NextPart()
+			if err != nil {
+				break
+			}
+			if text := fromEntity(part, depth+1); text != "" {
+				kind, _, _ := part.Header.ContentType()
+				if kind != "text/html" {
+					return text
+				}
+				if html == "" {
+					html = text
+				}
+			}
+		}
+		return html
+	}
+
+	body, _ := io.ReadAll(entity.Body)
+	kind, _, _ := entity.Header.ContentType()
+	if kind == "text/html" {
+		return stripTags(string(body))
+	}
+	return strings.TrimSpace(string(body))
+}
+
+// stripTags removes markup without pretending to understand it. Enough for one
+// line of preview, and honest about being no more than that.
+func stripTags(html string) string {
+	var b strings.Builder
+	depth := 0
+	for _, r := range html {
+		switch {
+		case r == '<':
+			depth++
+		case r == '>':
+			if depth > 0 {
+				depth--
+			}
+		case depth == 0:
+			b.WriteRune(r)
+		}
+	}
+	return strings.Join(strings.Fields(b.String()), " ")
+}
+
+func cut(text string) string {
+	runes := []rune(text)
+	if len(runes) > snippetLimit {
+		return string(runes[:snippetLimit]) + "…"
+	}
+	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

@@ -0,0 +1,396 @@
+package imap
+
+import (
+	"crypto/ecdsa"
+	"crypto/elliptic"
+	"crypto/rand"
+	"crypto/tls"
+	"crypto/x509"
+	"crypto/x509/pkix"
+	"encoding/pem"
+	"math/big"
+	"net"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/emersion/go-imap/v2"
+	"github.com/emersion/go-imap/v2/imapserver"
+	"github.com/emersion/go-imap/v2/imapserver/imapmemserver"
+)
+
+// The round trip, against a real IMAP server rather than a stub of one. The
+// earlier tests cover the pure parts — what a sender renders as, where a snippet
+// is cut — and would all have passed with the fetch itself broken.
+func TestFlaggedMailComesBackAsMessages(t *testing.T) {
+	addr, pool := serveMailbox(t, []mail{
+		{subject: "Faktura 4711", from: "Anders Bo <[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)
+	}
+
+	// Two of the three. The newsletter is unflagged, and flagging is the whole
+	// signal: unread is a state the owner is still using.
+	if len(msgs) != 2 {
+		t.Fatalf("got %d messages, want the 2 flagged ones", len(msgs))
+	}
+	if msgs[0].Subject != "Faktura 4711" {
+		t.Errorf("first subject is %q", msgs[0].Subject)
+	}
+	if !strings.Contains(msgs[0].From, "[email protected]") {
+		t.Errorf("first sender is %q", msgs[0].From)
+	}
+	if msgs[0].UID == 0 {
+		t.Error("no uid came back, so a second run would fetch everything again")
+	}
+
+	// And reading on from a marker returns only what is newer, which is the whole
+	// of the deduplication.
+	rest, _, err := client.Since(msgs[0].UID, 25)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(rest) != 1 || rest[0].Subject != "Kontrakt" {
+		t.Fatalf("reading on from uid %d gave %d messages", msgs[0].UID, len(rest))
+	}
+}
+
+func TestAWrongPasswordIsRefusedClearly(t *testing.T) {
+	addr, pool := serveMailbox(t, nil)
+	_, err := Dial(Account{Host: addr, Username: "kw", Password: "forkert", RootCAs: pool})
+	if err == nil {
+		t.Fatal("a wrong password was accepted")
+	}
+	// Hosts say everything from AUTHENTICATIONFAILED to a sentence about the web,
+	// so the reply names the host and the user rather than repeating their words.
+	if !strings.Contains(err.Error(), "kw") {
+		t.Errorf("the error does not say whose login was refused: %v", err)
+	}
+}
+
+// A certificate this process signed itself must not be enough on its own.
+func TestAnUntrustedCertificateIsRefused(t *testing.T) {
+	addr, _ := serveMailbox(t, nil)
+	if _, err := Dial(Account{Host: addr, Username: "kw", Password: "hemmelig"}); err == nil {
+		t.Fatal("a self-signed certificate was accepted without being trusted")
+	}
+}
+
+type mail struct {
+	subject, from, body string
+	flagged             bool
+	// raw replaces the whole message when set, which is the only way to get a
+	// genuinely multipart one in.
+	raw string
+}
+
+// serveMailbox starts an in-process IMAP server over TLS and returns its address
+// and the pool that trusts it.
+func serveMailbox(t *testing.T, mails []mail) (string, *x509.CertPool) {
+	t.Helper()
+
+	cert, pool := selfSigned(t)
+	memServer := imapmemserver.New()
+	user := imapmemserver.NewUser("kw", "hemmelig")
+	if err := user.Create("INBOX", nil); err != nil {
+		t.Fatal(err)
+	}
+	memServer.AddUser(user)
+
+	for _, m := range mails {
+		flags := []imap.Flag{}
+		if m.flagged {
+			flags = append(flags, imap.FlagFlagged)
+		}
+		raw := m.raw
+		if raw == "" {
+			raw = "From: " + m.from + "\r\nSubject: " + m.subject +
+				"\r\nDate: Tue, 18 Aug 2026 10:00:00 +0200\r\n\r\n" + m.body + "\r\n"
+		}
+		if _, err := user.Append("INBOX", strings.NewReader(raw), &imap.AppendOptions{
+			Flags: flags,
+		}); err != nil {
+			t.Fatal(err)
+		}
+	}
+
+	srv := imapserver.New(&imapserver.Options{
+		NewSession: func(_ *imapserver.Conn) (imapserver.Session, *imapserver.GreetingData, error) {
+			return memServer.NewSession(), nil, nil
+		},
+		TLSConfig:    &tls.Config{Certificates: []tls.Certificate{cert}},
+		InsecureAuth: false,
+	})
+	t.Cleanup(func() { srv.Close() })
+
+	ln, err := tls.Listen("tcp", "127.0.0.1:0", &tls.Config{Certificates: []tls.Certificate{cert}})
+	if err != nil {
+		t.Fatal(err)
+	}
+	go srv.Serve(ln)
+
+	// "localhost", not the loopback address: the certificate names a host, and the
+	// client checks that name — as it should.
+	_, port, _ := net.SplitHostPort(ln.Addr().String())
+	return net.JoinHostPort("localhost", port), pool
+}
+
+func selfSigned(t *testing.T) (tls.Certificate, *x509.CertPool) {
+	t.Helper()
+
+	key, err := ecdsa.GenerateKey(elliptic.P256(), rand.Reader)
+	if err != nil {
+		t.Fatal(err)
+	}
+	template := x509.Certificate{
+		SerialNumber:          big.NewInt(1),
+		Subject:               pkix.Name{CommonName: "localhost"},
+		DNSNames:              []string{"localhost"},
+		IPAddresses:           []net.IP{net.ParseIP("127.0.0.1")},
+		NotBefore:             time.Now().Add(-time.Hour),
+		NotAfter:              time.Now().Add(time.Hour),
+		KeyUsage:              x509.KeyUsageDigitalSignature | x509.KeyUsageCertSign,
+		ExtKeyUsage:           []x509.ExtKeyUsage{x509.ExtKeyUsageServerAuth},
+		IsCA:                  true,
+		BasicConstraintsValid: true,
+	}
+	der, err := x509.CreateCertificate(rand.Reader, &template, &template, &key.PublicKey, key)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	certPEM := pem.EncodeToMemory(&pem.Block{Type: "CERTIFICATE", Bytes: der})
+	keyDER, err := x509.MarshalECPrivateKey(key)
+	if err != nil {
+		t.Fatal(err)
+	}
+	keyPEM := pem.EncodeToMemory(&pem.Block{Type: "EC PRIVATE KEY", Bytes: keyDER})
+
+	cert, err := tls.X509KeyPair(certPEM, keyPEM)
+	if err != nil {
+		t.Fatal(err)
+	}
+	pool := x509.NewCertPool()
+	pool.AppendCertsFromPEM(certPEM)
+	return cert, pool
+}
+
+// The bug this was written for: every press of "Fetch now" made the same mail
+// into a task again. The marker the next run starts from is the uid, and if it
+// comes back as zero the marker never moves.
+func TestEveryMessageCarriesAUID(t *testing.T) {
+	addr, pool := serveMailbox(t, []mail{
+		{subject: "En", from: "[email protected]", body: "en", flagged: true},
+		{subject: "To", from: "[email protected]", body: "to", 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)
+	}
+	for _, m := range msgs {
+		if m.UID == 0 {
+			t.Fatalf("%q came back without a uid; the marker would never move and "+
+				"every run would make it into a task again", m.Subject)
+		}
+	}
+	if msgs[0].UID == msgs[1].UID {
+		t.Error("two messages share a uid")
+	}
+}
+
+// The other half of the same report: the snippet under a task's title read
+// "--=_be71cb39… Content-Transfer-Encoding: 8bit Content-Type: text/plain".
+func TestAMultipartMailReadsAsItsText(t *testing.T) {
+	const boundary = "=_be71cb3975bdfbc60a16327cb2f49c23"
+	body := "This is a multi-part message.\r\n" +
+		"--" + boundary + "\r\n" +
+		"Content-Transfer-Encoding: 8bit\r\n" +
+		"Content-Type: text/plain; charset=UTF-8; format=flowed\r\n\r\n" +
+		"Hej igen,\r\n\r\nVi har normalt 3 slags. :)\r\n" +
+		"--" + boundary + "\r\n" +
+		"Content-Type: text/html; charset=UTF-8\r\n\r\n" +
+		"<html><body><p>Hej igen</p></body></html>\r\n" +
+		"--" + boundary + "--\r\n"
+
+	addr, pool := serveMailbox(t, []mail{{
+		flagged: true,
+		raw: "Content-Type: multipart/alternative; boundary=\"" + boundary + "\"\r\n" +
+			"From: [email protected]\r\nSubject: Re: Kaffebestilling\r\n" +
+			"Date: Tue, 18 Aug 2026 10:00:00 +0200\r\n\r\n" + body,
+	}})
+
+	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) != 1 {
+		t.Fatalf("got %d messages", len(msgs))
+	}
+
+	got := msgs[0].Snippet
+	for _, junk := range []string{boundary, "Content-Transfer-Encoding", "Content-Type", "<html>", "<p>"} {
+		if strings.Contains(got, junk) {
+			t.Errorf("the snippet still carries %q: %q", junk, got)
+		}
+	}
+	if !strings.HasPrefix(got, "Hej igen") {
+		t.Errorf("the snippet does not start with the text of the mail: %q", got)
+	}
+}
+
+// The marker is ours, not the server's.
+//
+// A mailbox read with a marker above everything in it must come back empty. The
+// query says so, but a server is free to read the range differently — one reads
+// `1272:*` as `0:1272` and hands back the lot, which is how the same mail became
+// a task every ten minutes while the marker stood still at 1271. The filter is
+// on this side now, so the invariant holds whatever comes back.
+func TestNothingAtOrBelowTheMarkerComesBack(t *testing.T) {
+	addr, pool := serveMailbox(t, []mail{
+		{subject: "En", from: "[email protected]", body: "en", flagged: true},
+		{subject: "To", from: "[email protected]", body: "to", flagged: true},
+		{subject: "Tre", from: "[email protected]", body: "tre", flagged: true},
+	})
+	client, err := Dial(Account{Host: addr, Username: "kw", Password: "hemmelig", RootCAs: pool})
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer client.Close()
+
+	all, highest, err := client.Since(0, 25)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(all) != 3 {
+		t.Fatalf("got %d messages on the first read, want 3", len(all))
+	}
+
+	// Read again from the marker the first run would have written.
+	rest, again, err := client.Since(highest, 25)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(rest) != 0 {
+		t.Errorf("%d message(s) came back at or below the marker: %v", len(rest), rest[0].Subject)
+	}
+	// And the marker must not go backwards, or the next run reads them all again.
+	if again < highest {
+		t.Errorf("the marker moved back from %d to %d", highest, again)
+	}
+
+	// Every message, individually: none of them may reappear once passed.
+	for _, m := range all {
+		later, _, err := client.Since(m.UID, 25)
+		if err != nil {
+			t.Fatal(err)
+		}
+		for _, l := range later {
+			if l.UID <= m.UID {
+				t.Errorf("reading from %d gave %d back", m.UID, l.UID)
+			}
+		}
+	}
+}
+
+// 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

@@ -37,6 +37,23 @@ type Runner struct {
 	// startable from main.
 	SyncGmail func(ctx context.Context, user *store.User) (int, error)
 
+	// SyncMailbox reads one IMAP mailbox. Supplied by the HTTP layer for the same
+	// 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
 }
 
@@ -60,7 +77,18 @@ func (r *Runner) Start(ctx context.Context) {
 	// need a public webhook and a Cloud Pub/Sub topic, which is a lot of Google
 	// 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, "gmail", 10*time.Minute, r.syncGmailAccounts)
+	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() }
@@ -95,6 +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.
@@ -122,6 +161,15 @@ func (r *Runner) sendDueReminders(ctx context.Context) error {
 			"due":     rem.RemindAt.Format(time.RFC3339),
 		})
 
+		// And to the devices that asked for it. This was missing: reminders went out
+		// in-app and by mail, so somebody with the tab closed and no mail configured
+		// got a notification that never arrived — which is the case a reminder is
+		// for. Notifications from other people's actions did push; only the timed
+		// ones did not, and the interface said "on for this device" either way.
+		if r.Push != nil {
+			r.Push(rem.UserID, rem.TaskContent, reminderBody(rem.RemindAt), rem.ProjectID)
+		}
+
 		if r.mail.Configured() && rem.UserEmail != "" {
 			link := r.cfg.BaseURL + "/projekt/" + rem.ProjectID
 			if err := r.mail.SendReminder(ctx, rem.UserEmail, rem.UserName, rem.TaskContent, link); err != nil {
@@ -135,6 +183,12 @@ func (r *Runner) sendDueReminders(ctx context.Context) error {
 	return nil
 }
 
+// reminderBody is the line under the task's title. The time rather than the date:
+// a reminder arrives when it is due, so the day is today and saying so is noise.
+func reminderBody(at time.Time) string {
+	return at.Format("15:04")
+}
+
 // --- backups ---------------------------------------------------------------------
 
 const (
@@ -247,26 +301,91 @@ func rotateBackups(cfg *config.Config, log *slog.Logger) error {
 
 // --- gmail ---------------------------------------------------------------------------
 
-// syncGmailAccounts polls every connected mailbox.
+// syncMailboxes polls every connected mailbox, Gmail and IMAP alike.
 //
-// One at a time, and a failure on one account does not stop the others: a revoked
-// token or an expired refresh is a problem for that person alone.
-func (r *Runner) syncGmailAccounts(ctx context.Context) error {
-	if r.SyncGmail == nil {
+// One sweep rather than two, now that both live in the same table. Nobody is
+// waiting, so no budget of its own — the request handler has one because a person
+// is watching a spinner. A host that has gone quiet costs this run its own dial
+// timeout and nothing else: the loop moves on, per mailbox and per person, so one
+// bad password does not stop everybody else's mail.
+func (r *Runner) syncMailboxes(ctx context.Context) error {
+	if r.SyncMailbox == nil {
 		return nil
 	}
-	users, err := r.db.UsersWithGmail(ctx)
+	userIDs, err := r.db.UsersWithMailboxes(ctx)
 	if err != nil {
 		return err
 	}
-	for _, user := range users {
-		created, err := r.SyncGmail(ctx, &user)
-		if err != nil {
-			r.log.Warn("gmail sync", "err", err, "user", user.ID)
+	for _, id := range userIDs {
+		user, err := r.db.UserByID(ctx, id)
+		if err != nil || user == nil {
 			continue
 		}
-		if created > 0 {
-			r.log.Info("tasks created from gmail", "user", user.ID, "count", created)
+		boxes, err := r.db.Mailboxes(ctx, id)
+		if err != nil {
+			r.log.Warn("list mailboxes", "err", err, "user", id)
+			continue
+		}
+		for i := range boxes {
+			var created int
+			var err error
+			// Gmail is fetched over HTTP with a token, IMAP over a connection with a
+			// password. Which one is a property of the row, not of the loop.
+			if boxes[i].Kind == "gmail" {
+				if r.SyncGmail == nil {
+					continue
+				}
+				created, err = r.SyncGmail(ctx, user)
+			} else {
+				created, err = r.SyncMailbox(ctx, user, &boxes[i])
+			}
+			if err != nil {
+				r.log.Warn("mailbox sync", "err", err, "user", id,
+					"kind", boxes[i].Kind, "mailbox", boxes[i].ID)
+				continue
+			}
+			if created > 0 {
+				r.log.Info("tasks created from a mailbox", "user", id,
+					"kind", boxes[i].Kind, "count", created)
+			}
+		}
+	}
+	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

internal/jobs/jobs_test.go

@@ -276,3 +276,59 @@ func backupFiles(t *testing.T, cfg *config.Config) []string {
 	}
 	return out
 }
+
+// A reminder that nobody receives is not a reminder.
+//
+// The job sent them in-app and by mail. Somebody with the tab closed and no mail
+// server configured — which is the setup the docker one-liner produces — got
+// nothing, while the settings page said notifications were on for the device.
+// The push half was simply never wired: notifications from other people's actions
+// went out, only the timed ones did not.
+func TestADueReminderReachesTheDevices(t *testing.T) {
+	runner, db, _ := newRunner(t)
+	user := seedUser(t, db)
+
+	type sent struct{ userID, title, projectID string }
+	var got []sent
+	runner.Push = func(userID, title, body, projectID string) {
+		got = append(got, sent{userID, title, projectID})
+	}
+
+	inbox, err := db.InboxID(t.Context(), user.ID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	task := &store.Task{ProjectID: inbox, Content: "ring til Anders", CreatedBy: user.ID}
+	if err := db.CreateTask(t.Context(), task, nil); err != nil {
+		t.Fatal(err)
+	}
+	// A minute ago, so it is due rather than upcoming.
+	at := time.Now().Add(-time.Minute)
+	if _, err := db.CreateReminder(t.Context(), task.ID, user.ID, &at, nil); err != nil {
+		t.Fatal(err)
+	}
+
+	if err := runner.sendDueReminders(t.Context()); err != nil {
+		t.Fatal(err)
+	}
+
+	if len(got) != 1 {
+		t.Fatalf("%d reminders reached the devices, want 1", len(got))
+	}
+	if got[0].userID != user.ID {
+		t.Errorf("it went to %q", got[0].userID)
+	}
+	if got[0].title != "ring til Anders" {
+		t.Errorf("the title is %q, not the task", got[0].title)
+	}
+
+	// And once. A reminder that arrives on every sweep is worse than one that does
+	// not arrive at all.
+	got = nil
+	if err := runner.sendDueReminders(t.Context()); err != nil {
+		t.Fatal(err)
+	}
+	if len(got) != 0 {
+		t.Errorf("the same reminder went out %d more times", len(got))
+	}
+}

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 +1,380 @@
+package store
+
+import (
+	"context"
+	"database/sql"
+	"fmt"
+	"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"`
+
+	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`
+
+// CalendarAccountFor returns a person's connection to one provider, or nil.
+func (db *DB) CalendarAccountFor(ctx context.Context, userID, provider string) (*CalendarAccount, error) {
+	row := db.QueryRowContext(ctx, `SELECT `+calendarAccountColumns+`
+		FROM calendar_accounts WHERE user_id = ? AND provider = ?`, 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.
+	_, err = db.ExecContext(ctx, `
+		INSERT INTO calendar_accounts (`+calendarAccountColumns+`)
+		VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?)
+		ON CONFLICT (user_id, provider) 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())
+	if err != nil {
+		return err
+	}
+
+	// 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 = ?`,
+		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)
+	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
+}

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.go

@@ -0,0 +1,253 @@
+package store
+
+import (
+	"context"
+	"database/sql"
+	"encoding/json"
+	"fmt"
+	"time"
+)
+
+// Mailbox is one connected mailbox belonging to one person.
+type Mailbox struct {
+	ID     string `json:"id"`
+	UserID string `json:"-"`
+	Kind   string `json:"kind"` // "gmail" or "imap"
+	Name   string `json:"name"`
+
+	Host     string `json:"host,omitempty"`
+	Username string `json:"username,omitempty"`
+	Password string `json:"-"` // never leaves the server
+	Folder   string `json:"folder,omitempty"`
+
+	RefreshToken string    `json:"-"`
+	AccessToken  string    `json:"-"`
+	ExpiresAt    time.Time `json:"-"`
+	Label        string    `json:"label,omitempty"`
+
+	// ProjectID is where this mailbox's tasks land. Empty means the inbox, and so
+	// does an id the person can no longer write to.
+	ProjectID string `json:"project_id,omitempty"`
+	Trigger   string `json:"trigger,omitempty"` // "starred" or "label"
+
+	// Seen is the message ids Gmail has already turned into tasks. IMAP does not
+	// need it — uids are monotonic, so LastUID says the same in one number — but
+	// Gmail's query is a rolling window rather than a marker.
+	Seen []string `json:"-"`
+
+	LastUID    uint32    `json:"last_uid,omitempty"`
+	LastSyncAt time.Time `json:"last_sync_at,omitempty"`
+	CreatedAt  time.Time `json:"created_at"`
+}
+
+const mailboxColumns = `id, user_id, kind, name, host, username, password, folder,
+	refresh_token, access_token, expires_at, label, trigger_kind, seen, project_id,
+	last_uid, last_sync_at, created_at`
+
+// Mailboxes returns everything one person has connected, oldest first.
+func (db *DB) Mailboxes(ctx context.Context, userID string) ([]Mailbox, error) {
+	rows, err := db.QueryContext(ctx,
+		`SELECT `+mailboxColumns+` FROM mailboxes WHERE user_id = ? ORDER BY created_at`, userID)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	var out []Mailbox
+	for rows.Next() {
+		m, err := db.scanMailbox(rows)
+		if err != nil {
+			return nil, err
+		}
+		out = append(out, m)
+	}
+	return out, rows.Err()
+}
+
+// Mailbox returns one, and only to the person it belongs to: the id is enough to
+// find a row, so the owner is part of the question rather than checked after.
+func (db *DB) Mailbox(ctx context.Context, userID, id string) (*Mailbox, error) {
+	row := db.QueryRowContext(ctx,
+		`SELECT `+mailboxColumns+` FROM mailboxes WHERE id = ? AND user_id = ?`, id, userID)
+	m, err := db.scanMailbox(row)
+	if err == sql.ErrNoRows {
+		return nil, nil
+	}
+	if err != nil {
+		return nil, err
+	}
+	return &m, nil
+}
+
+// MailboxOfKind returns a person's mailbox of one kind, or nil. Gmail is one per
+// person because the OAuth flow is: connecting again replaces what was there.
+func (db *DB) MailboxOfKind(ctx context.Context, userID, kind string) (*Mailbox, error) {
+	row := db.QueryRowContext(ctx,
+		`SELECT `+mailboxColumns+` FROM mailboxes WHERE user_id = ? AND kind = ?`, userID, kind)
+	m, err := db.scanMailbox(row)
+	if err == sql.ErrNoRows {
+		return nil, nil
+	}
+	if err != nil {
+		return nil, err
+	}
+	return &m, nil
+}
+
+// SaveMailbox 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) SaveMailbox(ctx context.Context, m *Mailbox) error {
+	if m.ID == "" {
+		m.ID = NewID()
+	}
+	if m.CreatedAt.IsZero() {
+		m.CreatedAt = time.Now()
+	}
+	if m.Folder == "" {
+		m.Folder = "INBOX"
+	}
+
+	password, err := db.sealValue(m.Password)
+	if err != nil {
+		return fmt.Errorf("seal password: %w", err)
+	}
+	refresh, err := db.sealValue(m.RefreshToken)
+	if err != nil {
+		return fmt.Errorf("seal refresh_token: %w", err)
+	}
+	access, err := db.sealValue(m.AccessToken)
+	if err != nil {
+		return fmt.Errorf("seal access_token: %w", err)
+	}
+	// Not sealed: which mails have been read is not a secret, and a column of
+	// ciphertext here would only make the table harder to look at.
+	seen, err := json.Marshal(m.Seen)
+	if err != nil {
+		return err
+	}
+	if m.Trigger == "" {
+		m.Trigger = "starred"
+	}
+
+	_, err = db.ExecContext(ctx, `
+		INSERT INTO mailboxes (`+mailboxColumns+`)
+		VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
+		ON CONFLICT (id) DO UPDATE SET
+		    name = excluded.name,
+		    host = excluded.host,
+		    username = excluded.username,
+		    password = excluded.password,
+		    folder = excluded.folder,
+		    refresh_token = excluded.refresh_token,
+		    access_token = excluded.access_token,
+		    expires_at = excluded.expires_at,
+		    label = excluded.label,
+		    trigger_kind = excluded.trigger_kind,
+		    seen = excluded.seen,
+		    project_id = excluded.project_id,
+		    last_uid = excluded.last_uid,
+		    last_sync_at = excluded.last_sync_at`,
+		m.ID, m.UserID, m.Kind, m.Name, m.Host, m.Username, password, m.Folder,
+		refresh, access, unixOrZero(m.ExpiresAt), m.Label, m.Trigger, string(seen), m.ProjectID,
+		m.LastUID, unixOrZero(m.LastSyncAt), m.CreatedAt.Unix())
+	return err
+}
+
+// MarkMailboxRead 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) MarkMailboxRead(ctx context.Context, id string, lastUID uint32, at time.Time) error {
+	_, err := db.ExecContext(ctx,
+		`UPDATE mailboxes SET last_uid = ?, last_sync_at = ? WHERE id = ?`,
+		lastUID, at.Unix(), id)
+	return err
+}
+
+// DeleteMailbox disconnects one. The tasks it made stay: they are the person's
+// work now, not the mailbox's.
+func (db *DB) DeleteMailbox(ctx context.Context, userID, id string) error {
+	_, err := db.ExecContext(ctx, `DELETE FROM mailboxes WHERE id = ? AND user_id = ?`, id, userID)
+	return err
+}
+
+// UsersWithMailboxes returns everybody the sweep has to visit.
+func (db *DB) UsersWithMailboxes(ctx context.Context) ([]string, error) {
+	rows, err := db.QueryContext(ctx, `SELECT DISTINCT user_id FROM mailboxes`)
+	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()
+}
+
+type scanner interface {
+	Scan(dest ...any) error
+}
+
+func (db *DB) scanMailbox(row scanner) (Mailbox, error) {
+	var m Mailbox
+	var expires, lastSync, created int64
+	var seen string
+	err := row.Scan(&m.ID, &m.UserID, &m.Kind, &m.Name, &m.Host, &m.Username,
+		&m.Password, &m.Folder, &m.RefreshToken, &m.AccessToken, &expires,
+		&m.Label, &m.Trigger, &seen, &m.ProjectID, &m.LastUID, &lastSync, &created)
+	if err != nil {
+		return m, err
+	}
+	// A row that somehow holds nonsense here is not worth failing a whole sync
+	// over: an empty list means everything looks new, which is recoverable.
+	_ = json.Unmarshal([]byte(seen), &m.Seen)
+
+	for _, field := range []*string{&m.Password, &m.RefreshToken, &m.AccessToken} {
+		plain, err := db.unsealValue(*field)
+		if err != nil {
+			return m, err
+		}
+		*field = plain
+	}
+
+	m.ExpiresAt = timeOrZero(expires)
+	m.LastSyncAt = timeOrZero(lastSync)
+	m.CreatedAt = time.Unix(created, 0)
+	return m, nil
+}
+
+// sealValue and unsealValue are the single-string versions of the map helpers in
+// notifications.go. Without a key they pass the value through, which is what the
+// tests that never set one expect.
+func (db *DB) sealValue(v string) (string, error) {
+	if db.box == nil {
+		return v, nil
+	}
+	return db.box.Seal(v)
+}
+
+func (db *DB) unsealValue(v string) (string, error) {
+	if db.box == nil {
+		return v, nil
+	}
+	return db.box.Unseal(v)
+}
+
+func unixOrZero(t time.Time) int64 {
+	if t.IsZero() {
+		return 0
+	}
+	return t.Unix()
+}
+
+func timeOrZero(unix int64) time.Time {
+	if unix == 0 {
+		return time.Time{}
+	}
+	return time.Unix(unix, 0)
+}

internal/store/mailboxes_test.go

@@ -0,0 +1,264 @@
+package store
+
+import (
+	"context"
+	"path/filepath"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/kristianwind/verdande/internal/secret"
+)
+
+func TestAMailboxIsStoredSealedAndComesBackWhole(t *testing.T) {
+	db, userID := sealedStore(t)
+	ctx := context.Background()
+
+	const password = "abcd-efgh-ijkl-mnop"
+	m := &Mailbox{
+		UserID:   userID,
+		Kind:     "imap",
+		Name:     "iCloud",
+		Host:     "imap.mail.me.com:993",
+		Username: "[email protected]",
+		Password: password,
+	}
+	if err := db.SaveMailbox(ctx, m); err != nil {
+		t.Fatal(err)
+	}
+
+	var stored string
+	if err := db.QueryRowContext(ctx,
+		`SELECT password FROM mailboxes WHERE id = ?`, m.ID).Scan(&stored); err != nil {
+		t.Fatal(err)
+	}
+	if strings.Contains(stored, password) {
+		t.Fatalf("the password is in the row as typed: %s", stored)
+	}
+
+	back, err := db.Mailbox(ctx, userID, m.ID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if back == nil {
+		t.Fatal("the mailbox was not found")
+	}
+	if back.Password != password {
+		t.Errorf("got password %q", back.Password)
+	}
+	if back.Folder != "INBOX" {
+		t.Errorf("the folder defaulted to %q, want INBOX", back.Folder)
+	}
+}
+
+// The question that prompted the table: two people on one instance, each with
+// their own mailbox, neither seeing the other's.
+func TestAMailboxBelongsToOnePerson(t *testing.T) {
+	db, kristian := sealedStore(t)
+	ctx := context.Background()
+
+	andreas := &User{Email: "[email protected]", Name: "Andreas"}
+	if err := db.CreateUser(ctx, andreas, "Indbakke"); err != nil {
+		t.Fatal(err)
+	}
+
+	mine := &Mailbox{UserID: kristian, Kind: "imap", Host: "imap.mail.me.com:993", Username: "kw"}
+	theirs := &Mailbox{UserID: andreas.ID, Kind: "imap", Host: "imap.fastmail.com:993", Username: "andreas"}
+	for _, m := range []*Mailbox{mine, theirs} {
+		if err := db.SaveMailbox(ctx, m); err != nil {
+			t.Fatal(err)
+		}
+	}
+
+	list, err := db.Mailboxes(ctx, kristian)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(list) != 1 || list[0].Username != "kw" {
+		t.Fatalf("got %d mailboxes for Kristian, want only his own", len(list))
+	}
+
+	// And the id alone is not enough to reach somebody else's.
+	other, err := db.Mailbox(ctx, kristian, theirs.ID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if other != nil {
+		t.Error("one person read another's mailbox by its id")
+	}
+}
+
+// Several mailboxes each is the ordinary case — a work Gmail and a private
+// iCloud — and is the whole reason this is a table rather than a setting.
+func TestOnePersonCanHaveSeveral(t *testing.T) {
+	db, userID := sealedStore(t)
+	ctx := context.Background()
+
+	for _, host := range []string{"imap.mail.me.com:993", "imap.fastmail.com:993"} {
+		if err := db.SaveMailbox(ctx, &Mailbox{
+			UserID: userID, Kind: "imap", Host: host, Username: "kw",
+		}); err != nil {
+			t.Fatal(err)
+		}
+	}
+	list, err := db.Mailboxes(ctx, userID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(list) != 2 {
+		t.Fatalf("got %d mailboxes, want 2", len(list))
+	}
+}
+
+// The same mailbox twice would make two tasks out of every mail.
+func TestTheSameMailboxTwiceIsRefused(t *testing.T) {
+	db, userID := sealedStore(t)
+	ctx := context.Background()
+
+	first := &Mailbox{UserID: userID, Kind: "imap", Host: "imap.mail.me.com:993", Username: "kw"}
+	if err := db.SaveMailbox(ctx, first); err != nil {
+		t.Fatal(err)
+	}
+	again := &Mailbox{UserID: userID, Kind: "imap", Host: "imap.mail.me.com:993", Username: "kw"}
+	if err := db.SaveMailbox(ctx, again); err == nil {
+		t.Error("the same host and username was accepted a second time")
+	}
+}
+
+func TestReadingProgressIsRemembered(t *testing.T) {
+	db, userID := sealedStore(t)
+	ctx := context.Background()
+
+	m := &Mailbox{UserID: userID, Kind: "imap", Host: "imap.mail.me.com:993", Username: "kw"}
+	if err := db.SaveMailbox(ctx, m); err != nil {
+		t.Fatal(err)
+	}
+	at := time.Now().Truncate(time.Second)
+	if err := db.MarkMailboxRead(ctx, m.ID, 4711, at); err != nil {
+		t.Fatal(err)
+	}
+
+	back, err := db.Mailbox(ctx, userID, m.ID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if back.LastUID != 4711 {
+		t.Errorf("last uid is %d", back.LastUID)
+	}
+	if !back.LastSyncAt.Equal(at) {
+		t.Errorf("last sync is %v, want %v", back.LastSyncAt, at)
+	}
+	// The credentials it was holding must not have been rewritten as a side effect.
+	if back.Host != "imap.mail.me.com:993" {
+		t.Errorf("the host changed to %q", back.Host)
+	}
+}
+
+// Disconnecting takes the mailbox, not the work it produced.
+func TestDisconnectingKeepsTheTasks(t *testing.T) {
+	db, userID := sealedStore(t)
+	ctx := context.Background()
+
+	m := &Mailbox{UserID: userID, Kind: "imap", Host: "imap.mail.me.com:993", Username: "kw"}
+	if err := db.SaveMailbox(ctx, m); err != nil {
+		t.Fatal(err)
+	}
+	if err := db.DeleteMailbox(ctx, userID, m.ID); err != nil {
+		t.Fatal(err)
+	}
+	list, err := db.Mailboxes(ctx, userID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(list) != 0 {
+		t.Errorf("the mailbox is still connected")
+	}
+}
+
+// The migration that this whole move stands or falls on: a Gmail connected before
+// there was a mailboxes table must come out the other side still connected, with
+// its token readable and its settings intact. Nobody should have to reconnect
+// because the server tidied up.
+func TestAGmailConnectedBeforeTheMoveSurvivesIt(t *testing.T) {
+	dir := t.TempDir()
+	box, err := secret.Open("", t.TempDir())
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// A database at the state before 0017, with a sealed token written the way the
+	// settings table wrote them.
+	db, userID := storeAt(t, dir, box)
+	sealed, err := box.Seal("1//0-the-original-refresh-token")
+	if err != nil {
+		t.Fatal(err)
+	}
+	values := `{"refresh_token":"` + sealed + `","trigger":"label","label":"Verdande",` +
+		`"email":"[email protected]","seen":["abc","def"],"project_id":"p-1"}`
+	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`,
+		userID, values); err != nil {
+		t.Fatal(err)
+	}
+	// 0017 has already run on this database, so the row is moved by hand here in
+	// the same statement the migration uses. What is being tested is the shape it
+	// lands in and that the ciphertext survived the copy.
+	if _, err := db.ExecContext(context.Background(), `
+		INSERT INTO mailboxes (id, user_id, kind, name, host, username, password, folder,
+			refresh_token, access_token, expires_at, label, trigger_kind, seen, project_id,
+			last_uid, last_sync_at, created_at)
+		SELECT lower(hex(randomblob(16))), s.user_id, 'gmail',
+			json_extract(s.values_json, '$.email'), '', json_extract(s.values_json, '$.email'),
+			'', 'INBOX', json_extract(s.values_json, '$.refresh_token'), '', 0,
+			json_extract(s.values_json, '$.label'), json_extract(s.values_json, '$.trigger'),
+			json_extract(s.values_json, '$.seen'), json_extract(s.values_json, '$.project_id'),
+			0, 0, unixepoch()
+		FROM user_settings s WHERE s.scope = 'gmail'`); err != nil {
+		t.Fatal(err)
+	}
+
+	moved, err := db.MailboxOfKind(context.Background(), userID, "gmail")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if moved == nil {
+		t.Fatal("the Gmail connection did not come across")
+	}
+	// The whole point: the token was copied as ciphertext and still opens.
+	if moved.RefreshToken != "1//0-the-original-refresh-token" {
+		t.Errorf("the token came out as %q", moved.RefreshToken)
+	}
+	if moved.Trigger != "label" || moved.Label != "Verdande" {
+		t.Errorf("the trigger came out as %q/%q", moved.Trigger, moved.Label)
+	}
+	if moved.Username != "[email protected]" {
+		t.Errorf("the address came out as %q", moved.Username)
+	}
+	if moved.ProjectID != "p-1" {
+		t.Errorf("the destination project came out as %q", moved.ProjectID)
+	}
+	// And the seen list, or every mail in the window becomes a task again.
+	if len(moved.Seen) != 2 || moved.Seen[0] != "abc" {
+		t.Errorf("the seen list came out as %v", moved.Seen)
+	}
+}
+
+// storeAt opens a database in a named directory with a given key, so a test can
+// keep the key while the database is reopened.
+func storeAt(t *testing.T, dir string, box *secret.Box) (*DB, string) {
+	t.Helper()
+	db, err := Open(filepath.Join(dir, "test.db"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	t.Cleanup(func() { db.Close() })
+	db.UseSecrets(box)
+
+	user := &User{Email: "[email protected]", Name: "Kristian"}
+	if err := db.CreateUser(context.Background(), user, "Indbakke"); err != nil {
+		t.Fatal(err)
+	}
+	return db, user.ID
+}

internal/store/migrations/0014_mailboxes.sql

@@ -0,0 +1,57 @@
+-- Mailboxes: one row per connected mailbox, not one setting per person.
+--
+-- Gmail lived in `user_settings` under scope 'gmail'. That table has `user_id` as
+-- its whole primary key, so it holds exactly one scope per person and its upsert
+-- rewrites the scope name on conflict — adding IMAP beside Gmail there would have
+-- deleted the Gmail connection without saying so. Migration 0011 warns about this
+-- in as many words, and the warning was nearly walked into a second time.
+--
+-- The shape is wrong for the thing anyway. A person has mailboxes, plural: a work
+-- Gmail and a private iCloud is the ordinary case, not the exotic one. A row each
+-- says that. It also answers the question that prompted this — every mailbox
+-- belongs to a user, so two people on the same instance connect their own and see
+-- only their own. The one piece that stays instance-wide is the Google OAuth
+-- client, which is a single registration everybody signs in through, and that is
+-- correct: it is the app, not the account.
+--
+-- `kind` rather than two tables. What differs is how the credential is obtained —
+-- OAuth for Gmail, a password for IMAP — and what differs is a nullable column,
+-- not a schema. What is the same is everything the sync loop touches: which
+-- mailbox, how far it has read, when it last ran.
+--
+-- `password` and `refresh_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 — a fact worth knowing before adding a third secret column.
+--
+-- `last_uid` is IMAP's place-marker and means nothing for Gmail, which keeps its
+-- own by query. Zero is "nothing read yet" for both.
+CREATE TABLE mailboxes (
+    id            TEXT PRIMARY KEY,
+    user_id       TEXT NOT NULL REFERENCES users (id) ON DELETE CASCADE,
+    kind          TEXT NOT NULL CHECK (kind IN ('gmail', 'imap')),
+    name          TEXT NOT NULL DEFAULT '',
+
+    -- IMAP
+    host          TEXT NOT NULL DEFAULT '',
+    username      TEXT NOT NULL DEFAULT '',
+    password      TEXT NOT NULL DEFAULT '',
+    folder        TEXT NOT NULL DEFAULT 'INBOX',
+
+    -- Gmail
+    refresh_token TEXT NOT NULL DEFAULT '',
+    access_token  TEXT NOT NULL DEFAULT '',
+    expires_at    INTEGER NOT NULL DEFAULT 0,
+    label         TEXT NOT NULL DEFAULT '',
+
+    last_uid      INTEGER NOT NULL DEFAULT 0,
+    last_sync_at  INTEGER NOT NULL DEFAULT 0,
+    created_at    INTEGER NOT NULL
+);
+
+-- The sweep asks "whose mailboxes are due", so it reads by user.
+CREATE INDEX mailboxes_by_user ON mailboxes (user_id);
+
+-- The same mailbox twice is a mistake, not a choice: two rows would make two
+-- tasks out of every mail. Gmail's uniqueness is the account, IMAP's is the host
+-- and the username together, and `kind` keeps the two from colliding.
+CREATE UNIQUE INDEX mailboxes_once ON mailboxes (user_id, kind, host, username);

internal/store/migrations/0015_mailbox_trigger_and_seen.sql

@@ -0,0 +1,22 @@
+-- Room for Gmail beside the others.
+--
+-- Only the two columns. Moving the data is a separate migration on purpose: the
+-- Gmail handlers still read user_settings, and a migration that emptied that table
+-- before they were rewritten would disconnect a working mailbox. Additive first,
+-- and the move when the code on the other side is ready for it.
+--
+-- Gmail lived in `user_settings` under scope 'gmail' because it was the only
+-- integration of its kind. Now there are two, and two places to look for the same
+-- question — which mailboxes does this person have — is one place too many.
+--
+-- `seen` is Gmail's own deduplication: a list of message ids it has already turned
+-- into tasks. IMAP does not need it, because uids are monotonic and `last_uid`
+-- answers the same question in one number. Gmail's query is a 30-day window rather
+-- than a marker, so the list is what it has.
+ALTER TABLE mailboxes ADD COLUMN seen TEXT NOT NULL DEFAULT '[]';
+
+-- What makes a mail into a task: 'starred', or 'label' with the name in `label`.
+-- Its own column rather than packed into `label` with a separator — a column that
+-- holds two things joined by a colon is a column somebody parses wrongly later,
+-- and a label named with a colon in it would do it on the first day.
+ALTER TABLE mailboxes ADD COLUMN trigger_kind TEXT NOT NULL DEFAULT 'starred';

internal/store/migrations/0016_mailbox_project.sql

@@ -0,0 +1,12 @@
+-- Where a mailbox's tasks land.
+--
+-- Gmail carried this as `project_id` in its settings blob. It belongs to the
+-- mailbox, and it is worth having for the ones read over IMAP too: a work mailbox
+-- filing into the work project is the obvious thing to want, and the alternative
+-- is everything landing in the inbox to be moved by hand.
+--
+-- Empty means the person's inbox, which is also what an id that no longer names a
+-- project they can write to falls back to. Not a foreign key for that reason: a
+-- deleted project should quietly stop being the destination, not refuse the delete
+-- or take the mailbox down with it.
+ALTER TABLE mailboxes ADD COLUMN project_id TEXT NOT NULL DEFAULT '';

internal/store/migrations/0017_gmail_is_a_mailbox.sql

@@ -0,0 +1,46 @@
+-- Gmail's rows move in beside the ones read over IMAP.
+--
+-- Held back until now on purpose: this empties the settings row, and running it
+-- while the handlers still read that row would have disconnected a working
+-- mailbox. internal/httpapi now reads the mailboxes table, so the move is safe.
+--
+-- The values move across still sealed. Both tables seal with the same key and
+-- store the same string, so copying the ciphertext verbatim is not a shortcut
+-- around the encryption — it is the encryption, untouched. That also means this
+-- migration does not need the key, which a migration has no business holding.
+--
+-- `username` is the address the account reports, and it is what makes the unique
+-- index meaningful. It may be empty on rows that never got that far; two such rows
+-- cannot exist for one person anyway, because the settings table could only hold
+-- one.
+INSERT INTO mailboxes (
+    id, user_id, kind, name, host, username, password, folder,
+    refresh_token, access_token, expires_at, label, trigger_kind, seen, project_id,
+    last_uid, last_sync_at, created_at
+)
+SELECT
+    lower(hex(randomblob(16))),
+    s.user_id,
+    'gmail',
+    COALESCE(json_extract(s.values_json, '$.email'), 'Gmail'),
+    '',
+    COALESCE(json_extract(s.values_json, '$.email'), ''),
+    '',
+    'INBOX',
+    COALESCE(json_extract(s.values_json, '$.refresh_token'), ''),
+    COALESCE(json_extract(s.values_json, '$.access_token'), ''),
+    COALESCE(json_extract(s.values_json, '$.expires_at'), 0),
+    COALESCE(json_extract(s.values_json, '$.label'), ''),
+    COALESCE(json_extract(s.values_json, '$.trigger'), 'starred'),
+    COALESCE(json_extract(s.values_json, '$.seen'), '[]'),
+    COALESCE(json_extract(s.values_json, '$.project_id'), ''),
+    0,
+    0,
+    unixepoch()
+FROM user_settings s
+WHERE s.scope = 'gmail'
+  AND COALESCE(json_extract(s.values_json, '$.refresh_token'), '') <> '';
+
+-- Emptied, not deleted: the row may hold nothing else today, but the table is
+-- shared and a DELETE here would be a habit worth not forming.
+UPDATE user_settings SET values_json = '{}' WHERE scope = 'gmail';

internal/store/migrations/0018_notes.sql

@@ -0,0 +1,88 @@
+-- Notes.
+--
+-- 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 this program is gone. It is also what makes full-text
+-- search and anything an AI does over notes cheap: both read text.
+--
+-- Under a project rather than in a folder tree of its own. Projects, groups and
+-- labels already exist and are already shared, already have roles, already have a
+-- trash. A second hierarchy to file things in is one too many, and a note that
+-- belongs to a project inherits every one of those answers instead of needing its
+-- own. A note with no project is loose, the way a task in the inbox is.
+--
+-- `deleted_at` and `created_by` follow tasks exactly, including SET NULL: an
+-- account can be removed without taking somebody else's notes with it.
+CREATE TABLE notes (
+    id          TEXT PRIMARY KEY,
+    project_id  TEXT REFERENCES projects (id) ON DELETE CASCADE,
+    title       TEXT NOT NULL DEFAULT '',
+    body        TEXT NOT NULL DEFAULT '',
+    created_by  TEXT REFERENCES users (id) ON DELETE SET NULL,
+    pinned      INTEGER NOT NULL DEFAULT 0,
+    created_at  INTEGER NOT NULL,
+    updated_at  INTEGER NOT NULL,
+    deleted_at  INTEGER,
+
+    -- The same Danish transliteration as tasks carry, and for the same reason:
+    -- unicode61 folds diacritics, so "grøn" is findable as "gron", but it does
+    -- nothing for æ→ae or å→aa, which is how Danes actually type when the keyboard
+    -- is not theirs.
+    fold        TEXT GENERATED ALWAYS AS (
+                    replace(replace(replace(replace(replace(replace(
+                        title || ' ' || body,
+                        'ø', 'o'), 'Ø', 'o'),
+                        'æ', 'ae'), 'Æ', 'ae'),
+                        'å', 'aa'), 'Å', 'aa')
+                ) STORED
+);
+
+CREATE INDEX notes_by_project ON notes (project_id, deleted_at, updated_at DESC);
+
+-- What a note points at: a task, another note, a project.
+--
+-- Derived from the body every time it is saved, never edited directly. The text
+-- stays the truth; this is an index over it — which is what makes the question
+-- worth asking backwards. "What refers to this task" must not mean searching every
+-- note's prose, or the panel that shows it would be too slow to leave open.
+--
+-- `target_id` is deliberately not a foreign key. A link to something that has been
+-- deleted is a fact about the note, and it should read as a dead link rather than
+-- vanish or block the delete.
+CREATE TABLE note_links (
+    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)
+);
+
+CREATE INDEX note_links_backwards ON note_links (kind, target_id);
+
+CREATE VIRTUAL TABLE notes_fts USING fts5 (
+    title,
+    body,
+    fold,
+    id UNINDEXED,
+    project_id UNINDEXED,
+    content = 'notes',
+    content_rowid = 'rowid',
+    tokenize = 'unicode61 remove_diacritics 2'
+);
+
+CREATE TRIGGER notes_fts_insert AFTER INSERT ON notes BEGIN
+    INSERT INTO notes_fts (rowid, title, body, fold, id, project_id)
+    VALUES (new.rowid, new.title, new.body, new.fold, new.id, new.project_id);
+END;
+
+CREATE TRIGGER notes_fts_delete AFTER DELETE ON notes BEGIN
+    INSERT INTO notes_fts (notes_fts, rowid, title, body, fold, id, project_id)
+    VALUES ('delete', old.rowid, old.title, old.body, old.fold, old.id, old.project_id);
+END;
+
+CREATE TRIGGER notes_fts_update AFTER UPDATE ON notes BEGIN
+    INSERT INTO notes_fts (notes_fts, rowid, title, body, fold, id, project_id)
+    VALUES ('delete', old.rowid, old.title, old.body, old.fold, old.id, old.project_id);
+    INSERT INTO notes_fts (rowid, title, body, fold, id, project_id)
+    VALUES (new.rowid, new.title, new.body, new.fold, new.id, new.project_id);
+END;

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/notes.go

@@ -0,0 +1,434 @@
+package store
+
+import (
+	"context"
+	"database/sql"
+	"regexp"
+	"strings"
+	"time"
+)
+
+// 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"`
+	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
+	// a note whose text says something else.
+	Links []NoteLink `json:"links,omitempty"`
+}
+
+// NoteLink is one reference from a note to something else.
+type NoteLink struct {
+	Kind     string `json:"kind"` // "task", "note" or "project"
+	TargetID string `json:"target_id"`
+}
+
+const noteColumns = `id, project_id, title, body, created_by, pinned,
+	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
+// into 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".
+var (
+	projectRef = regexp.MustCompile(`(?:^|\s)#([\p{L}\p{N}_-]{1,64})`)
+	// [[a note]] by title, the spelling every note-taking program has settled on.
+	noteRef = regexp.MustCompile(`\[\[([^\]\n]{1,200})\]\]`)
+	// A task by id, which is what a link pasted out of the app carries.
+	taskRef = regexp.MustCompile(`(?:/opgave/|task:)([0-9a-fA-F-]{36})`)
+)
+
+// SaveNote writes a note and rebuilds what it points at.
+//
+// The links are torn down and rebuilt rather than diffed. A note's body is small,
+// the set is small, and a diff would be a second description of the same fact —
+// one that can disagree with the text, which is the one thing this must never do.
+func (db *DB) SaveNote(ctx context.Context, n *Note) error {
+	if n.ID == "" {
+		n.ID = NewID()
+	}
+	now := time.Now()
+	if n.CreatedAt.IsZero() {
+		n.CreatedAt = now
+	}
+	n.UpdatedAt = now
+
+	// 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
+		if n.ProjectID != "" {
+			projectID = n.ProjectID
+		}
+		var createdBy any
+		if n.CreatedBy != "" {
+			createdBy = n.CreatedBy
+		}
+
+		if _, err := tx.ExecContext(ctx, `
+			INSERT INTO notes (id, project_id, title, body, created_by, pinned, created_at, updated_at)
+			VALUES (?, ?, ?, ?, ?, ?, ?, ?)
+			ON CONFLICT (id) DO UPDATE SET
+			    project_id = excluded.project_id,
+			    title = excluded.title,
+			    body = excluded.body,
+			    pinned = excluded.pinned,
+			    updated_at = excluded.updated_at`,
+			n.ID, projectID, n.Title, n.Body, createdBy, n.Pinned,
+			n.CreatedAt.Unix(), n.UpdatedAt.Unix()); err != nil {
+			return err
+		}
+
+		if _, err := tx.ExecContext(ctx, `DELETE FROM note_links WHERE note_id = ?`, n.ID); err != nil {
+			return err
+		}
+		n.Links = LinksIn(n.Body)
+		for _, l := range n.Links {
+			if _, err := tx.ExecContext(ctx,
+				`INSERT OR IGNORE INTO note_links (note_id, kind, target_id) VALUES (?, ?, ?)`,
+				n.ID, l.Kind, l.TargetID); err != nil {
+				return err
+			}
+		}
+		return nil
+	})
+}
+
+// LinksIn reads the references out of a body.
+//
+// Exported because it is worth testing on its own, and because the editor wants
+// the same answer while somebody is typing rather than after they have saved.
+func LinksIn(body string) []NoteLink {
+	seen := map[NoteLink]bool{}
+	var out []NoteLink
+	add := func(kind, target string) {
+		l := NoteLink{Kind: kind, TargetID: target}
+		if target == "" || seen[l] {
+			return
+		}
+		seen[l] = true
+		out = append(out, l)
+	}
+
+	for _, m := range taskRef.FindAllStringSubmatch(body, -1) {
+		add("task", strings.ToLower(m[1]))
+	}
+	for _, m := range projectRef.FindAllStringSubmatch(body, -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]))
+	}
+	return out
+}
+
+// firstLine is the title a note gets when it has not been given one. Markdown
+// heading marks are stripped: "# Møde" is titled "Møde", not "# Møde".
+func firstLine(body string) string {
+	for _, line := range strings.Split(body, "\n") {
+		line = strings.TrimSpace(strings.TrimLeft(strings.TrimSpace(line), "#"))
+		if line != "" {
+			if len([]rune(line)) > 120 {
+				return string([]rune(line)[:120])
+			}
+			return line
+		}
+	}
+	return ""
+}
+
+// Note returns one, or nil when it is not there or is in the trash.
+func (db *DB) Note(ctx context.Context, id string) (*Note, error) {
+	row := db.QueryRowContext(ctx,
+		`SELECT `+noteColumns+` FROM notes WHERE id = ? AND deleted_at IS NULL`, id)
+	n, err := scanNote(row)
+	if err == sql.ErrNoRows {
+		return nil, nil
+	}
+	if err != nil {
+		return nil, err
+	}
+	links, err := db.linksOf(ctx, n.ID)
+	if err != nil {
+		return nil, err
+	}
+	n.Links = links
+	return &n, nil
+}
+
+// NotesInProject lists a project's notes, pinned first and newest after.
+func (db *DB) NotesInProject(ctx context.Context, projectID string) ([]Note, error) {
+	return db.notesWhere(ctx,
+		`WHERE project_id = ? AND deleted_at IS NULL ORDER BY pinned DESC, updated_at DESC`,
+		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 = ?)
+		ORDER BY updated_at DESC`, kind, targetID)
+}
+
+// SearchNotes matches title and body, in either spelling of a Danish word.
+func (db *DB) SearchNotes(ctx context.Context, query string, limit int) ([]Note, error) {
+	if strings.TrimSpace(query) == "" {
+		return nil, nil
+	}
+	if limit <= 0 {
+		limit = 50
+	}
+	expr := MatchExprOver(query, "title", "body")
+	if expr == "" {
+		return nil, nil
+	}
+	// 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.
+	return 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)
+}
+
+// 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.
+func (db *DB) DeleteNote(ctx context.Context, id string) error {
+	_, err := db.ExecContext(ctx,
+		`UPDATE notes SET deleted_at = ?, updated_at = ? WHERE id = ? AND deleted_at IS NULL`,
+		time.Now().Unix(), time.Now().Unix(), id)
+	return err
+}
+
+// RestoreNote takes it back out.
+func (db *DB) RestoreNote(ctx context.Context, id string) error {
+	_, err := db.ExecContext(ctx,
+		`UPDATE notes SET deleted_at = NULL, updated_at = ? WHERE id = ?`,
+		time.Now().Unix(), id)
+	return err
+}
+
+func (db *DB) notesWhere(ctx context.Context, where string, args ...any) ([]Note, error) {
+	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
+	}
+	defer rows.Close()
+
+	var out []Note
+	for rows.Next() {
+		n, err := scanNote(rows)
+		if err != nil {
+			return nil, err
+		}
+		out = append(out, n)
+	}
+	return out, rows.Err()
+}
+
+func (db *DB) linksOf(ctx context.Context, noteID string) ([]NoteLink, error) {
+	rows, err := db.QueryContext(ctx,
+		`SELECT kind, target_id FROM note_links WHERE note_id = ? ORDER BY kind, target_id`, noteID)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	var out []NoteLink
+	for rows.Next() {
+		var l NoteLink
+		if err := rows.Scan(&l.Kind, &l.TargetID); err != nil {
+			return nil, err
+		}
+		out = append(out, l)
+	}
+	return out, rows.Err()
+}
+
+func scanNote(row scanner) (Note, error) {
+	var n Note
+	var projectID, createdBy sql.NullString
+	var created, updated int64
+	var deleted, archived sql.NullInt64
+
+	if err := row.Scan(&n.ID, &projectID, &n.Title, &n.Body, &createdBy,
+		&n.Pinned, &created, &updated, &deleted, &archived); err != nil {
+		return n, err
+	}
+	n.ProjectID = projectID.String
+	n.CreatedBy = createdBy.String
+	n.CreatedAt = time.Unix(created, 0)
+	n.UpdatedAt = time.Unix(updated, 0)
+	if deleted.Valid {
+		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

@@ -0,0 +1,371 @@
+package store
+
+import (
+	"context"
+	"strings"
+	"testing"
+)
+
+// The point of the whole thing: a #tag in a note is the same tag as in a task.
+// Not a second kind that looks alike and has to be kept in step by hand.
+func TestATagInANoteIsTheSameTagAsInATask(t *testing.T) {
+	db, userID := sealedStore(t)
+	ctx := context.Background()
+
+	n := &Note{
+		CreatedBy: userID,
+		Body:      "Mødet med #Firma gik fint. Følg op sammen med #Regnskab.",
+	}
+	if err := db.SaveNote(ctx, n); err != nil {
+		t.Fatal(err)
+	}
+
+	var projects []string
+	for _, l := range n.Links {
+		if l.Kind == "project" {
+			projects = append(projects, l.TargetID)
+		}
+	}
+	if len(projects) != 2 {
+		t.Fatalf("read %v out of the note, want the two projects", n.Links)
+	}
+	// 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)
+	}
+}
+
+// Backwards is the direction that makes it a second brain rather than a folder.
+func TestANoteIsFoundFromWhatItPointsAt(t *testing.T) {
+	db, userID := sealedStore(t)
+	ctx := context.Background()
+
+	const taskID = "01a01694-a25c-7000-a50f-d72ab33f9b6a"
+	notes := []*Note{
+		{CreatedBy: userID, Body: "Aftalt på mødet, se /opgave/" + taskID},
+		{CreatedBy: userID, Body: "Intet at gøre med den sag."},
+	}
+	for _, n := range notes {
+		if err := db.SaveNote(ctx, n); err != nil {
+			t.Fatal(err)
+		}
+	}
+
+	found, err := db.NotesLinking(ctx, "task", taskID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(found) != 1 {
+		t.Fatalf("%d notes point at the task, want 1", len(found))
+	}
+	if !strings.HasPrefix(found[0].Title, "Aftalt") {
+		t.Errorf("the wrong note came back: %q", found[0].Title)
+	}
+}
+
+// The links are an index over the text, so editing the text must move them.
+// A stale link is worse than none: it says a connection exists that does not.
+func TestEditingANoteRewritesWhatItPointsAt(t *testing.T) {
+	db, userID := sealedStore(t)
+	ctx := context.Background()
+
+	n := &Note{CreatedBy: userID, Body: "Handler om #Firma"}
+	if err := db.SaveNote(ctx, n); err != nil {
+		t.Fatal(err)
+	}
+	if before, _ := db.NotesLinking(ctx, "project", "Firma"); len(before) != 1 {
+		t.Fatal("the first save did not record the link")
+	}
+
+	n.Body = "Handler om #Regnskab i stedet"
+	if err := db.SaveNote(ctx, n); err != nil {
+		t.Fatal(err)
+	}
+
+	stale, err := db.NotesLinking(ctx, "project", "Firma")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(stale) != 0 {
+		t.Errorf("the note still points at Firma after the mention was removed")
+	}
+	if fresh, _ := db.NotesLinking(ctx, "project", "Regnskab"); len(fresh) != 1 {
+		t.Errorf("the new mention was not recorded")
+	}
+}
+
+// A list of untitled notes is a list nobody can read.
+func TestANoteTakesItsTitleFromItsFirstLine(t *testing.T) {
+	db, userID := sealedStore(t)
+	ctx := context.Background()
+
+	for _, c := range []struct{ body, want string }{
+		{"# Møde med Anders\n\nHan ville gerne...", "Møde med Anders"},
+		{"\n\n  Løse tanker  \nmere", "Løse tanker"},
+		{"", ""},
+	} {
+		n := &Note{CreatedBy: userID, Body: c.body}
+		if err := db.SaveNote(ctx, n); err != nil {
+			t.Fatal(err)
+		}
+		if n.Title != c.want {
+			t.Errorf("body %q gave title %q, want %q", c.body, n.Title, c.want)
+		}
+	}
+}
+
+// Danish spelling, both ways round — the same generosity tasks already get.
+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,
+		Body:      "Grønt regnskab\n\nMålt på årsbasis for Århus.",
+	}); err != nil {
+		t.Fatal(err)
+	}
+
+	for _, q := range []string{"grønt", "gront", "århus", "aarhus", "regnskab"} {
+		found, err := db.SearchNotes(ctx, q, 10)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if len(found) != 1 {
+			t.Errorf("%q found %d notes, want 1", q, len(found))
+		}
+	}
+}
+
+// Deleting is the trash, the way it is everywhere else in this program. A note is
+// the one place somebody can lose an hour of writing to one keystroke.
+func TestADeletedNoteCanComeBack(t *testing.T) {
+	db, userID := sealedStore(t)
+	ctx := context.Background()
+
+	n := &Note{CreatedBy: userID, Body: "Vigtigt"}
+	if err := db.SaveNote(ctx, n); err != nil {
+		t.Fatal(err)
+	}
+	if err := db.DeleteNote(ctx, n.ID); err != nil {
+		t.Fatal(err)
+	}
+	if gone, _ := db.Note(ctx, n.ID); gone != nil {
+		t.Error("a deleted note is still returned")
+	}
+	if err := db.RestoreNote(ctx, n.ID); err != nil {
+		t.Fatal(err)
+	}
+	back, err := db.Note(ctx, n.ID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if back == nil || back.Body != "Vigtigt" {
+		t.Error("the note did not come back whole")
+	}
+}
+
+func TestWhatIsReadOutOfABody(t *testing.T) {
+	for _, c := range []struct {
+		name, body string
+		want       []NoteLink
+	}{
+		{"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"}}},
+		{"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) {
+			got := LinksIn(c.body)
+			if len(got) != len(c.want) {
+				t.Fatalf("got %v, want %v", got, c.want)
+			}
+			for i := range got {
+				if got[i] != c.want[i] {
+					t.Errorf("got %v, want %v", got[i], c.want[i])
+				}
+			}
+		})
+	}
+}
+
+// The number beside a project is what is left to do: not finished, not deleted.
+// It replaced a count of people, which said 2 on an empty project.
+func TestTheProjectCountIsWhatIsLeft(t *testing.T) {
+	db, userID := sealedStore(t)
+	ctx := context.Background()
+
+	p := &Project{Name: "Tallene", OwnerID: userID}
+	if err := db.CreateProject(ctx, p); err != nil {
+		t.Fatal(err)
+	}
+
+	count := func() int {
+		list, err := db.ListProjects(ctx, userID, false)
+		if err != nil {
+			t.Fatal(err)
+		}
+		for _, x := range list {
+			if x.ID == p.ID {
+				return x.OpenCount
+			}
+		}
+		t.Fatal("the project is not in the list")
+		return -1
+	}
+
+	if n := count(); n != 0 {
+		t.Errorf("an empty project counts %d", n)
+	}
+
+	var ids []string
+	for _, c := range []string{"en", "to", "tre"} {
+		task := &Task{ProjectID: p.ID, Content: c, CreatedBy: userID}
+		if err := db.CreateTask(ctx, task, nil); err != nil {
+			t.Fatal(err)
+		}
+		ids = append(ids, task.ID)
+	}
+	if n := count(); n != 3 {
+		t.Errorf("three tasks count %d", n)
+	}
+
+	if _, err := db.CompleteTask(ctx, ids[0], userID); err != nil {
+		t.Fatal(err)
+	}
+	if n := count(); n != 2 {
+		t.Errorf("after finishing one, the count is %d, want 2", n)
+	}
+
+	if err := db.DeleteTask(ctx, ids[1]); err != nil {
+		t.Fatal(err)
+	}
+	if n := count(); n != 1 {
+		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)
+	}
+}

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)
@@ -272,44 +295,6 @@ func (db *DB) UserByMailToken(ctx context.Context, token string) (*User, error)
 	return db.scanUser(ctx, `SELECT `+userColumns+` FROM users WHERE mail_token = ?`, token)
 }
 
-// UsersWithGmail returns everybody who has connected a mailbox, which is who the
-// poller has to visit. Selected by the presence of a refresh token rather than by a
-// flag, so a disconnected account drops out of the sweep the moment its tokens are
-// cleared.
-func (db *DB) UsersWithGmail(ctx context.Context) ([]User, error) {
-	rows, err := db.QueryContext(ctx, `
-		SELECT u.id FROM users u
-		JOIN user_settings s ON s.user_id = u.id
-		WHERE s.scope = 'gmail' AND s.values_json LIKE '%"refresh_token":"%'`)
-	if err != nil {
-		return nil, err
-	}
-	var ids []string
-	for rows.Next() {
-		var id string
-		if err := rows.Scan(&id); err != nil {
-			rows.Close()
-			return nil, err
-		}
-		ids = append(ids, id)
-	}
-	err = rows.Err()
-	rows.Close()
-	if err != nil {
-		return nil, err
-	}
-
-	out := make([]User, 0, len(ids))
-	for _, id := range ids {
-		user, err := db.UserByID(ctx, id)
-		if err != nil {
-			continue
-		}
-		out = append(out, *user)
-	}
-	return out, nil
-}
-
 // --- per-user settings ------------------------------------------------------------------
 
 // UserSettings reads one scope of a person's integration settings. A missing row is
@@ -327,6 +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

internal/store/projects.go

@@ -30,6 +30,11 @@ type Project struct {
 	Role Role
 	// MemberCount is how many people can see it; 1 means it is not shared.
 	MemberCount int
+
+	// OpenCount is what is left to do: not deleted, not finished. It is the number
+	// the sidebar shows, because a number beside a project in a task app is read as
+	// tasks whatever it was meant to be.
+	OpenCount int
 }
 
 type Section struct {
@@ -50,6 +55,13 @@ func (db *DB) ListProjects(ctx context.Context, userID string, includeArchived b
 		       p.archived, p.sort_order, p.created_at, p.updated_at,
 		       CASE WHEN p.owner_id = ? THEN 'owner' ELSE COALESCE(m.role, '') END AS role,
 		       (SELECT count(*) FROM project_members pm WHERE pm.project_id = p.id) + 1 AS member_count,
+		       -- What is left to do, which is what the number beside a project in the
+		       -- sidebar means to the person reading it. It used to show member_count,
+		       -- and a "2" on an empty project read as two tasks to everybody who saw
+		       -- it — including the person who wrote the app.
+		       (SELECT count(*) FROM tasks t
+		         WHERE t.project_id = p.id AND t.deleted_at IS NULL AND t.completed_at IS NULL
+		       ) AS open_count,
 		       CASE WHEN p.owner_id = ? THEN p.group_id END AS group_id
 		FROM projects p
 		LEFT JOIN project_members m ON m.project_id = p.id AND m.user_id = ?
@@ -88,6 +100,9 @@ func (db *DB) GetProject(ctx context.Context, projectID, userID string) (*Projec
 		       p.archived, p.sort_order, p.created_at, p.updated_at,
 		       ? AS role,
 		       (SELECT count(*) FROM project_members pm WHERE pm.project_id = p.id) + 1,
+		       (SELECT count(*) FROM tasks t
+		         WHERE t.project_id = p.id AND t.deleted_at IS NULL AND t.completed_at IS NULL
+		       ),
 		       CASE WHEN p.owner_id = ? THEN p.group_id END
 		FROM projects p WHERE p.id = ? AND p.deleted_at IS NULL`, string(role), userID, projectID)
 	if err != nil {
@@ -113,7 +128,7 @@ func scanProject(rows *sql.Rows) (Project, error) {
 	var role string
 
 	err := rows.Scan(&p.ID, &p.Name, &p.Color, &icon, &p.ViewMode, &p.OwnerID, &isInbox,
-		&archived, &p.SortOrder, &created, &updated, &role, &p.MemberCount, &groupID)
+		&archived, &p.SortOrder, &created, &updated, &role, &p.MemberCount, &p.OpenCount, &groupID)
 	if err != nil {
 		return p, err
 	}

internal/store/savemailbox_test.go

@@ -0,0 +1,40 @@
+package store
+
+import (
+	"context"
+	"testing"
+)
+
+// Saving a mailbox that is already there must update it, not fail.
+//
+// The row is written again on every token refresh and every time Gmail's seen
+// list changes. If that write errors, the tasks a sync made are kept and the note
+// of having made them is not — so the same mail becomes a task again on the next
+// sweep, once every ten minutes, forever.
+func TestSavingAnExistingMailboxUpdatesIt(t *testing.T) {
+	db, userID := sealedStore(t)
+	ctx := context.Background()
+
+	m := &Mailbox{UserID: userID, Kind: "gmail", Username: "[email protected]",
+		RefreshToken: "r", Seen: []string{"a"}}
+	if err := db.SaveMailbox(ctx, m); err != nil {
+		t.Fatal(err)
+	}
+
+	m.Seen = []string{"a", "b"}
+	m.AccessToken = "fresh"
+	if err := db.SaveMailbox(ctx, m); err != nil {
+		t.Fatalf("saving it a second time failed: %v", err)
+	}
+
+	back, err := db.MailboxOfKind(ctx, userID, "gmail")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(back.Seen) != 2 {
+		t.Errorf("the seen list came back as %v", back.Seen)
+	}
+	if back.AccessToken != "fresh" {
+		t.Errorf("the token came back as %q", back.AccessToken)
+	}
+}

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.
 //
@@ -36,18 +43,45 @@ func FoldDanish(s string) string {
 // Returns "" when there is nothing searchable in the input; callers should treat
 // that as "no query" rather than as "match everything".
 func MatchExpr(query string) string {
+	return MatchExprOver(query, "content", "description")
+}
+
+// MatchExprOver is MatchExpr against a named set of columns.
+//
+// The columns have to be named because the index they are searched in decides
+// them: tasks carry content and description, notes carry title and body. Passing
+// one table's column names to the other's index is not a wrong answer but an
+// error — "no such column" — which is at least loud.
+func MatchExprOver(query string, columns ...string) string {
 	terms := tokenize(query)
-	if len(terms) == 0 {
+	if len(terms) == 0 || len(columns) == 0 {
 		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 {
 			b.WriteString(" AND ")
 		}
 		folded := FoldDanish(term)
-		b.WriteString(`({content description} : `)
+		b.WriteString(`({` + strings.Join(columns, " ") + `} : `)
 		b.WriteString(quote(term))
 		b.WriteString(`* OR fold : `)
 		b.WriteString(quote(folded))
@@ -60,6 +94,11 @@ func MatchExpr(query string) string {
 // 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

@@ -84,22 +84,23 @@ func TestATokenWrittenBeforeTheKeyStillWorks(t *testing.T) {
 	}
 }
 
-// UsersWithGmail finds people by the presence of the key, not its value, so it
-// must keep working now that the value is ciphertext.
+// The sweep finds people by the presence of a mailbox, so it must keep working
+// now that the credential in it is ciphertext.
 func TestTheSweepStillFindsAConnectedMailbox(t *testing.T) {
 	db, userID := sealedStore(t)
 	ctx := context.Background()
 
-	if err := db.SetUserSettings(ctx, userID, "gmail",
-		map[string]any{"refresh_token": "1//0-token"}); err != nil {
+	if err := db.SaveMailbox(ctx, &Mailbox{
+		UserID: userID, Kind: "gmail", RefreshToken: "1//0-token",
+	}); err != nil {
 		t.Fatal(err)
 	}
-	users, err := db.UsersWithGmail(ctx)
+	users, err := db.UsersWithMailboxes(ctx)
 	if err != nil {
 		t.Fatal(err)
 	}
 	if len(users) != 1 {
-		t.Fatalf("the sweep found %d connected mailboxes, want 1", len(users))
+		t.Fatalf("the sweep found %d people with mailboxes, want 1", len(users))
 	}
 }
 

internal/store/users.go

@@ -36,8 +36,13 @@ 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 +109,7 @@ 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 +117,11 @@ 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 +129,48 @@ 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 +440,20 @@ 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 = ?`,

mkdocs.yml

@@ -48,12 +48,14 @@ nav:
       - As a Rune: rune.md
       - Configuration: configuration.md
   - Using it:
+      - Signing in: signing-in.md
       - Quick add: quick-add.md
       - Filters: filters.md
       - Importing from Todoist: import.md
   - Connecting things:
       - Calendar and CalDAV: caldav.md
       - Mail to task: mail.md
+      - Mailboxes: mailboxes.md
       - Claude (MCP): mcp.md
       - AI features: ai.md
   # openapi.yaml is deliberately not in the nav: MkDocs copies it to the site as a

site/index.html

@@ -6,13 +6,18 @@
 		<title>verdande — self-hosted tasks, shared</title>
 		<meta
 			name="description"
-			content="Self-hosted tasks and projects, shared. One Go binary with SQLite inside it. CalDAV, mail-to-task and an MCP connector for Claude."
+			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."
 		/>
 		<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: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." />
+		<!-- Summary rather than the large card: the screenshot is a dense interface,
+		     and shrunk into a wide banner it reads as grey noise. -->
+		<meta name="twitter:card" content="summary" />
 
 		<link rel="icon" href="icon.svg" type="image/svg+xml" />
 
@@ -38,6 +43,10 @@
 				--font-mono: ui-monospace, 'SF Mono', 'JetBrains Mono', Menlo, monospace;
 			}
 
+			/* Written twice on purpose. The media query is what a first-time visitor
+			   gets; the attribute is what somebody who has chosen gets, and it has to
+			   win in both directions — a chosen light theme on a dark system as well
+			   as the other way round. A single rule cannot do both. */
 			@media (prefers-color-scheme: light) {
 				:root:not([data-theme='dark']) {
 					--ground: #faf9f7;
@@ -53,6 +62,63 @@
 				}
 			}
 
+			:root[data-theme='light'] {
+				--ground: #faf9f7;
+				--surface: #ffffff;
+				--surface-raised: #ffffff;
+				--line: #e5e3de;
+				--line-strong: #d3d0c9;
+				--ink: #1c201e;
+				--ink-muted: #5f6763;
+				--ink-faint: #8b918d;
+				--accent: #2f8f63;
+				--accent-ink: #ffffff;
+			}
+
+			.theme-toggle {
+				position: fixed;
+				top: 1rem;
+				right: 1rem;
+				z-index: 10;
+				width: 2.25rem;
+				height: 2.25rem;
+				display: grid;
+				place-items: center;
+				border: 1px solid var(--line);
+				border-radius: 999px;
+				background: var(--surface);
+				color: var(--ink-muted);
+				cursor: pointer;
+				font-size: 1rem;
+				line-height: 1;
+			}
+
+			.theme-toggle:hover {
+				color: var(--ink);
+				border-color: var(--line-strong);
+			}
+
+			/* Whichever screenshot does not belong to the theme in force is simply not
+			   there. Both are in the markup so neither has to be fetched at the moment
+			   somebody flips the switch. */
+			:root:not([data-theme='light']) .only-light,
+			:root[data-theme='dark'] .only-light {
+				display: none;
+			}
+
+			:root[data-theme='light'] .only-dark {
+				display: none;
+			}
+
+			@media (prefers-color-scheme: light) {
+				:root:not([data-theme='dark']) .only-light {
+					display: block;
+				}
+				:root:not([data-theme='dark']) .only-dark {
+					display: none;
+				}
+			}
+
 			*,
 			*::before,
 			*::after {
@@ -339,6 +405,89 @@
 				text-align: center;
 			}
 
+			/* --- zoom -------------------------------------------------------------
+
+			   A screenshot of an interface is unreadable at 280px in a three-column
+			   grid, which is where most of them sit. Clicking one opens it at the
+			   size it was taken.
+
+			   <dialog> rather than a hand-built overlay: Escape closes it, focus is
+			   trapped, the rest of the page is inert, and the browser does all three
+			   without a line of script. */
+			.shot img {
+				cursor: zoom-in;
+			}
+
+			/* Sized so the whole thing fits: a screenshot is 1.55 times wider than it
+			   is tall, so on a laptop the height is what runs out first. Left to grow,
+			   it pushed the caption and the close button off the top of the screen —
+			   and the button is the visible way out. */
+			dialog.zoom {
+				max-width: 96vw;
+				max-height: 100vh;
+				/* Wraps the image rather than the viewport. With a plain `auto` the box
+				   stayed full width, so the screenshot sat against the left edge and
+				   the close button ended up in the far corner, nowhere near it. */
+				width: fit-content;
+				margin: auto;
+				padding: 2.5rem 0 0;
+				border: 0;
+				background: transparent;
+				overflow: visible;
+			}
+
+			dialog.zoom::backdrop {
+				background: rgb(0 0 0 / 0.82);
+			}
+
+			dialog.zoom img {
+				max-width: 96vw;
+				max-height: 78vh;
+				width: auto;
+				height: auto;
+				display: block;
+				border-radius: var(--radius-lg);
+				cursor: zoom-out;
+			}
+
+			dialog.zoom figcaption {
+				margin-top: 0.75rem;
+				font-size: 0.8125rem;
+				color: #a8b0ac;
+				text-align: center;
+			}
+
+			/* The whole backdrop closes, so the button is a visible affordance rather
+			   than the only way out. */
+			dialog.zoom .close {
+				position: absolute;
+				top: 0;
+				right: 0;
+				background: none;
+				border: 0;
+				color: #a8b0ac;
+				font-size: 1.5rem;
+				line-height: 1;
+				cursor: pointer;
+				padding: 0.25rem 0.5rem;
+			}
+
+			dialog.zoom .close:hover {
+				color: #fff;
+			}
+
+			@media (prefers-reduced-motion: no-preference) {
+				dialog.zoom[open] {
+					animation: zoom-in 0.15s ease-out;
+				}
+				@keyframes zoom-in {
+					from {
+						opacity: 0;
+						transform: scale(0.98);
+					}
+				}
+			}
+
 			.shots {
 				display: grid;
 				grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
@@ -375,6 +524,9 @@
 	</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>
 				<span class="mark" aria-hidden="true">ᚹ</span>
@@ -434,9 +586,9 @@
 
 			<section>
 				<h2>What it looks like</h2>
-				<figure class="shot">
+				<figure class="shot only-dark">
 					<img
-						src="screenshots/today.png"
+						src="screenshots/today.webp"
 						alt="The Today view: a sidebar of projects, filters and labels beside a list of tasks due today, each with its priority ring, time and labels."
 						width="1400"
 						height="900"
@@ -445,10 +597,21 @@
 					<figcaption>Today. Dark is the default; there is a light theme too.</figcaption>
 				</figure>
 
+				<figure class="shot only-light">
+					<img
+						src="screenshots/today-light.webp"
+						alt="The Today view in the light theme: a sidebar of projects, filters and labels beside a list of tasks due today."
+						width="1400"
+						height="900"
+						loading="lazy"
+					/>
+					<figcaption>Today. Dark is the default; there is a light theme too.</figcaption>
+				</figure>
+
 				<div class="shots">
 					<figure class="shot">
 						<img
-							src="screenshots/board.png"
+							src="screenshots/board.webp"
 							alt="A project in board view: one column per section, with task cards showing due dates, labels and repetition."
 							width="1400"
 							height="900"
@@ -458,17 +621,17 @@
 					</figure>
 					<figure class="shot">
 						<img
-							src="screenshots/today-light.png"
-							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
-							src="screenshots/week.png"
+							src="screenshots/week.webp"
 							alt="Upcoming as a single week: seven columns of days, each holding the tasks due that day."
 							width="1400"
 							height="900"
@@ -478,8 +641,8 @@
 					</figure>
 					<figure class="shot">
 						<img
-							src="screenshots/detail.png"
-							alt="A task open in the detail drawer, with its description, due date, labels, sub-tasks and comments."
+							src="screenshots/detail.webp"
+							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"
@@ -488,17 +651,17 @@
 					</figure>
 					<figure class="shot">
 						<img
-							src="screenshots/themes.png"
-							alt="The settings page showing the five themes as swatches."
+							src="screenshots/themes.webp"
+							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
-							src="screenshots/history.png"
+							src="screenshots/history.webp"
 							alt="The instance-wide history page: who did what, in which project, filtered by person and event."
 							width="1400"
 							height="900"
@@ -526,6 +689,16 @@
 							invite link. Changes appear live.
 						</p>
 					</div>
+					<div class="cell">
+						<h3>Notes, beside the work</h3>
+						<p>
+							Rich text to write in, Markdown on disk. File a note in a project and
+							everybody in it can read it; <code>#project</code> and
+							<code>[[another note]]</code> are links, and a task shows what has been
+							written about it. A zip of Markdown goes in and comes back out the same
+							shape, so nothing is trapped here.
+						</p>
+					</div>
 					<div class="cell">
 						<h3>A real CalDAV server</h3>
 						<p>
@@ -541,10 +714,20 @@
 						</p>
 					</div>
 					<div class="cell">
-						<h3>Mail to task</h3>
+						<h3>Your mail, as an inbox</h3>
 						<p>
-							Forward an email to your own address and it becomes a task, subject
-							parsed like anything else you type.
+							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.
+						</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. Sign in with a passkey and there is no
+							password to forget either.
 						</p>
 					</div>
 					<div class="cell">
@@ -554,6 +737,22 @@
 							round trip is tested, not promised.
 						</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.
+						</p>
+					</div>
+					<div class="cell">
+						<h3>Who did what</h3>
+						<p>
+							Every change is written down — who moved it, who closed it, who let
+							somebody in. Delete the account and the trail stays: it is the
+							instance's record, not the person's.
+						</p>
+					</div>
 				</div>
 			</section>
 
@@ -605,5 +804,85 @@
 				</p>
 			</footer>
 		</div>
+
+		<!-- Zoom. Added by script rather than written into the markup, so a page with
+		     no JavaScript is exactly what it was before: the screenshots are still
+		     there, still readable, just not clickable. -->
+		<dialog class="zoom" aria-label="Screenshot, enlarged">
+			<button class="close" type="button" aria-label="Close">&times;</button>
+			<img alt="" />
+			<figcaption></figcaption>
+		</dialog>
+
+		<script>
+			// Runs before the zoom script and before anything is painted below it, so
+			// a chosen theme does not flash the other one first.
+			(function () {
+				var root = document.documentElement;
+				var stored = null;
+				try {
+					stored = localStorage.getItem('verdande-site-theme');
+				} catch (e) {
+					// Private browsing. The choice simply will not be remembered.
+				}
+				if (stored === 'light' || stored === 'dark') root.setAttribute('data-theme', stored);
+
+				document.querySelector('.theme-toggle').addEventListener('click', function () {
+					// What is on the screen right now, whether it came from a choice or
+					// from the system — otherwise the first press does nothing visible
+					// for somebody whose system already says light.
+					var showing =
+						root.getAttribute('data-theme') ||
+						(matchMedia('(prefers-color-scheme: light)').matches ? 'light' : 'dark');
+					var next = showing === 'light' ? 'dark' : 'light';
+					root.setAttribute('data-theme', next);
+					try {
+						localStorage.setItem('verdande-site-theme', next);
+					} catch (e) {}
+				});
+			})();
+
+			(function () {
+				var dialog = document.querySelector('dialog.zoom');
+				if (!dialog || typeof dialog.showModal !== 'function') return;
+
+				var big = dialog.querySelector('img');
+				var caption = dialog.querySelector('figcaption');
+
+				function open(img) {
+					big.src = img.currentSrc || img.src;
+					big.alt = img.alt;
+					var fig = img.closest('figure');
+					var text = fig && fig.querySelector('figcaption');
+					caption.textContent = text ? text.textContent : '';
+					dialog.showModal();
+				}
+
+				document.querySelectorAll('.shot img').forEach(function (img) {
+					// Focusable and operable from the keyboard: a control that only a
+					// mouse can reach is not a control everybody has.
+					img.tabIndex = 0;
+					img.setAttribute('role', 'button');
+					img.addEventListener('click', function () { open(img); });
+					img.addEventListener('keydown', function (event) {
+						if (event.key === 'Enter' || event.key === ' ') {
+							event.preventDefault();
+							open(img);
+						}
+					});
+				});
+
+				dialog.addEventListener('click', function (event) {
+					// The backdrop is the dialog itself; anything inside it is not.
+					if (event.target === dialog || event.target === big ||
+						event.target.classList.contains('close')) {
+						dialog.close();
+					}
+				});
+				// Let go of the image when it closes, so a large screenshot is not
+				// held in memory for the rest of the visit.
+				dialog.addEventListener('close', function () { big.removeAttribute('src'); });
+			})();
+		</script>
 	</body>
 </html>