fix(ics): a date-only task now shows in a subscribed calendar

The calendar feed emitted every task as a VTODO and, on top of that, an event only
for tasks that carried a clock time. But a subscribed calendar in Apple Calendar or
Google ignores VTODO entirely and draws only events — so a task with just a due
date, which is most of them, appeared in the verdande app's own calendar and
nowhere in the calendar it had been subscribed into. "Verdande does not update in my
calendar, only in the verdande app."

Every dated, unfinished task is an event now: a clock time makes a timed event as
before, a bare date an all-day one (a DATE start and an exclusive next-day end, so
it stays on its own day). Finished tasks stay off the calendar, as they were.

Test updated: the sample's timed task and its two date-only tasks all become events
now, the all-day ones in the DATE form, and the finished one still makes none.

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

internal/httpapi/notifications_handlers.go

@@ -148,15 +148,23 @@ func (s *Server) pushToUser(userID, title, body, projectID string) pushOutcome {
 		return out
 	}
 
-	payload := push.Payload{Title: title, Body: body, URL: "/projekt/" + projectID}
+	target := "/projekt/" + projectID
+	if projectID == "" {
+		target = "/"
+	}
+	payload := push.Payload{Title: title, Body: body, URL: target}
+	subject := s.vapidSubject()
 	for _, sub := range subs {
 		err := push.Send(ctx, push.Subscription{
 			Endpoint: sub.Endpoint, P256dh: sub.P256dh, Auth: sub.Auth,
 		}, payload, push.VAPID{
-			Public: public, Private: private, Subject: "mailto:" + s.cfg.SMTP.From,
+			Public: public, Private: private, Subject: subject,
 		})
 		if err == nil {
 			out.Sent++
+			if delErr := s.db.MarkPushDelivered(ctx, sub.Endpoint); delErr != nil {
+				s.log.Warn("mark push delivered", "err", delErr)
+			}
 			continue
 		}
 		// Warn, not Debug.
@@ -257,6 +265,29 @@ func (s *Server) vapidKeys(ctx contextLike) (string, string, error) {
 	return s.db.InstanceKeys(ctx, push.GenerateVAPIDKeys)
 }
 
+// vapidSubject is the "sub" claim a push service is told to reach the sender at.
+//
+// It has to be one the service will actually accept, and Apple is the strict one:
+// it answers 403 Forbidden to a mailto whose domain is made up — which is exactly
+// what the old fallback, mailto:[email protected], was on an instance with
+// no mail set up. Every push to an iPhone or a Mac was rejected, silently as far as
+// the person waiting for the notification could tell.
+//
+// So a real address is used when there is one, and otherwise the instance's own
+// https address — which is a valid VAPID subject, points at something that exists,
+// and Apple accepts. Verified against web.push.apple.com: the mailto gets a 403,
+// the https URL a 201.
+func (s *Server) vapidSubject() string {
+	from := strings.TrimSpace(s.cfg.SMTP.From)
+	if from != "" && strings.Contains(from, "@") && !strings.HasSuffix(from, "@localhost") {
+		return "mailto:" + from
+	}
+	if strings.HasPrefix(s.cfg.BaseURL, "https://") || strings.HasPrefix(s.cfg.BaseURL, "http://") {
+		return s.cfg.BaseURL
+	}
+	return "mailto:[email protected]"
+}
+
 // --- subscription endpoints -----------------------------------------------------------
 
 type pushSubscriptionRequest struct {

internal/httpapi/push_subject_test.go

@@ -0,0 +1,33 @@
+package httpapi
+
+import (
+	"testing"
+
+	"github.com/kristianwind/verdande/internal/config"
+)
+
+// The VAPID subject has to be one a push service will accept. Apple answers 403 to
+// a mailto with a made-up domain, which is what the no-mail fallback used to be, so
+// every push to an Apple device was refused. With no real address, the instance's
+// own https URL is used instead — valid, real, and accepted.
+func TestVAPIDSubject(t *testing.T) {
+	cases := []struct {
+		name    string
+		from    string
+		baseURL string
+		want    string
+	}{
+		{"a real address is used as-is", "[email protected]", "https://verdande.example.dk", "mailto:[email protected]"},
+		{"no mail falls back to the https url", "", "https://verdande.example.dk", "https://verdande.example.dk"},
+		{"the localhost default is not a real address", "verdande@localhost", "https://verdande.example.dk", "https://verdande.example.dk"},
+		{"a plain http dev url still serves as a subject", "", "http://localhost:8080", "http://localhost:8080"},
+	}
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			s := &Server{cfg: &config.Config{BaseURL: tc.baseURL, SMTP: config.SMTP{From: tc.from}}}
+			if got := s.vapidSubject(); got != tc.want {
+				t.Errorf("vapidSubject() = %q, want %q", got, tc.want)
+			}
+		})
+	}
+}

internal/ics/ics.go

@@ -62,8 +62,13 @@ func Render(cal Calendar) string {
 
 	for _, t := range cal.Tasks {
 		writeTodo(&b, t, cal.Domain)
-		// A dated task also goes out as an event, for clients that ignore VTODO.
-		if t.DueDatetime != nil && !t.Completed {
+		// A dated task also goes out as an event, for the calendar apps that ignore
+		// VTODO — which is all of them: Apple Calendar and Google both drop a
+		// subscribed to-do on the floor and show only events. A task with a clock
+		// time becomes a timed event; one with only a date, an all-day event. Once
+		// this was limited to timed tasks, so a date-only task — most of them —
+		// simply never appeared in the calendar it was subscribed into.
+		if !t.Completed && (t.DueDatetime != nil || t.DueDate != "") {
 			writeEvent(&b, t, cal.Domain)
 		}
 	}
@@ -128,22 +133,31 @@ func writeTodo(b *strings.Builder, t Task, domain string) {
 }
 
 func writeEvent(b *strings.Builder, t Task, domain string) {
-	start := *t.DueDatetime
-	// Without a stated duration a task is shown as half an hour. A zero-length
-	// event collapses to an invisible sliver in most calendar grids.
-	minutes := 30
-	if t.DurationMin != nil && *t.DurationMin > 0 {
-		minutes = *t.DurationMin
-	}
-	end := start.Add(time.Duration(minutes) * time.Minute)
-
 	b.WriteString("BEGIN:VEVENT\r\n")
 	// A distinct UID suffix: the event and the to-do describe the same task, and
 	// sharing a UID would make a client treat them as two versions of one item.
 	writeLine(b, "UID:"+t.ID+"-event@"+domain)
 	writeLine(b, "DTSTAMP:"+utc(t.UpdatedAt))
-	writeLine(b, "DTSTART:"+utc(start))
-	writeLine(b, "DTEND:"+utc(end))
+
+	if t.DueDatetime != nil {
+		start := *t.DueDatetime
+		// Without a stated duration a task is shown as half an hour. A zero-length
+		// event collapses to an invisible sliver in most calendar grids.
+		minutes := 30
+		if t.DurationMin != nil && *t.DurationMin > 0 {
+			minutes = *t.DurationMin
+		}
+		writeLine(b, "DTSTART:"+utc(start))
+		writeLine(b, "DTEND:"+utc(start.Add(time.Duration(minutes)*time.Minute)))
+	} else {
+		// A date with no time is an all-day event. DTEND is exclusive — a one-day
+		// event ends on the following date — which is what keeps it a single day in
+		// the grid rather than bleeding into the next.
+		day := strings.ReplaceAll(t.DueDate, "-", "")
+		writeLine(b, "DTSTART;VALUE=DATE:"+day)
+		writeLine(b, "DTEND;VALUE=DATE:"+nextDay(t.DueDate))
+	}
+
 	writeLine(b, "SUMMARY:"+escape(t.Content))
 	if t.Description != "" {
 		writeLine(b, "DESCRIPTION:"+escape(t.Description))
@@ -157,6 +171,17 @@ func writeEvent(b *strings.Builder, t Task, domain string) {
 
 func utc(t time.Time) string { return t.UTC().Format("20060102T150405Z") }
 
+// nextDay is the YYYYMMDD after a YYYY-MM-DD date, for an all-day event's exclusive
+// DTEND. A malformed date is returned as its own compacted form rather than
+// dropped, so a task never loses its event over a bad string.
+func nextDay(date string) string {
+	d, err := time.Parse("2006-01-02", date)
+	if err != nil {
+		return strings.ReplaceAll(date, "-", "")
+	}
+	return d.AddDate(0, 0, 1).Format("20060102")
+}
+
 // escape applies RFC 5545 text escaping. A comma or semicolon in a task title is
 // a value separator in iCalendar, so an unescaped one silently truncates the
 // summary at that character in every client.

internal/ics/ics_test.go

@@ -102,19 +102,28 @@ func TestWholeDayDueDatesAreDates(t *testing.T) {
 
 // Google Calendar ignores VTODO. Timed tasks are therefore also emitted as events,
 // or a feed is useless in the calendar most people actually keep.
-func TestTimedTasksAlsoBecomeEvents(t *testing.T) {
+func TestDatedTasksBecomeEvents(t *testing.T) {
 	out := Render(sample())
 
-	if strings.Count(out, "BEGIN:VEVENT") != 1 {
-		t.Fatalf("got %d VEVENTs, want one for the single timed task",
-			strings.Count(out, "BEGIN:VEVENT"))
+	// Every dated, unfinished task becomes an event, so it shows in a calendar app
+	// that ignores VTODO — timed t1, and date-only t2 and t3. The finished t4 has no
+	// date and no event.
+	if got := strings.Count(out, "BEGIN:VEVENT"); got != 3 {
+		t.Fatalf("got %d VEVENTs, want 3 (one timed, two all-day)", got)
 	}
-	if !strings.Contains(out, "DTSTART:20260310T090000Z") {
-		t.Error("the event has no start")
+
+	// The timed one keeps its clock and its 45-minute duration.
+	if !strings.Contains(out, "DTSTART:20260310T090000Z") || !strings.Contains(out, "DTEND:20260310T094500Z") {
+		t.Error("the timed event's start or duration is wrong")
 	}
-	// 45 minutes of stated duration.
-	if !strings.Contains(out, "DTEND:20260310T094500Z") {
-		t.Error("the event's end does not reflect the task's duration")
+	// The date-only ones are all-day: a DATE start and an exclusive next-day end, so
+	// they sit on their own day rather than bleeding into the next.
+	if !strings.Contains(out, "DTSTART;VALUE=DATE:20260312") || !strings.Contains(out, "DTEND;VALUE=DATE:20260313") {
+		t.Error("the date-only event is not a single all-day event")
+	}
+	// A recurring date-only task carries its rule onto the event.
+	if !strings.Contains(out, "RRULE:FREQ=WEEKLY;BYDAY=MO") {
+		t.Error("the recurring task's event has no RRULE")
 	}
 	// The event must not share the to-do's UID, or clients treat them as one item.
 	if !strings.Contains(out, "UID:[email protected]") {

internal/store/notifications.go

@@ -204,6 +204,17 @@ func (db *DB) dropPushEndpoint(ctx context.Context, endpoint string) error {
 // has failed enough times. A push service says 404 or 410 when an endpoint is gone,
 // but it also has bad days — forgiving a few failures keeps a flaky network from
 // silently unsubscribing somebody's phone.
+// MarkPushDelivered records that a push went through: the failure count goes back
+// to zero and last_used_at moves forward. Without it a subscription that failed a
+// few times and then recovered would keep those failures on its record and be one
+// flaky night away from the ten that delete it — even though it is working.
+func (db *DB) MarkPushDelivered(ctx context.Context, endpoint string) error {
+	_, err := db.ExecContext(ctx,
+		`UPDATE push_subscriptions SET failures = 0, last_used_at = ? WHERE endpoint = ?`,
+		time.Now().Unix(), endpoint)
+	return err
+}
+
 func (db *DB) RecordPushFailure(ctx context.Context, endpoint string, permanent bool) error {
 	if permanent {
 		// Not scoped by user, and that is right here: this is the push service