Skip reminder habit evaluation for completed delivery slots

src/reminders/worker.ts

@@ -22,14 +22,26 @@ export async function sendDueReminders(db: AppDatabase, config: ReminderConfig,
   // Retain recent delivery history and deduplication records without unbounded growth.
   db.delete(reminderDeliveries).where(lt(reminderDeliveries.updatedAt, now() - 90 * 86400000)).run();
   for (const { user } of rows) {
-    function due() {
+    function due(checkDeliveries = false) {
       const currentUser = db.select().from(users).where(eq(users.id, user.id)).get();
       const prefs = db.select().from(reminderSettings).where(eq(reminderSettings.userId, user.id)).get();
       if (!currentUser || !prefs?.enabled) return null;
       const timestamp = now(); const clock = localClock(timestamp, currentUser.timezone);
       if (inQuietHours(clock, prefs.quietStart, prefs.quietEnd)) return null;
-      const times = timesForDate(prefs, localDate(timestamp, currentUser.timezone)).filter(time => time <= clock);
+      const date = localDate(timestamp, currentUser.timezone);
+      const times = timesForDate(prefs, date).filter(time => time <= clock);
       if (!times.length) return null;
+      if (checkDeliveries) {
+        const previous = db.select().from(reminderDeliveries).where(and(eq(reminderDeliveries.userId, user.id), eq(reminderDeliveries.date, date))).all();
+        // This is only a cheap eligibility hint. The transaction below still owns claims.
+        // Let stale pending records reach its recovery step before skipping the user.
+        const stalePending = previous.some(row => row.status === 'pending' && row.updatedAt < timestamp - 60000);
+        if (!stalePending) {
+          const legacy = previous.find(row => row.slot === '*');
+          const claimable = (prior: typeof previous[number] | undefined) => !prior || (prior.status === 'deferred' && (prior.retryAt ?? 0) <= timestamp);
+          if (previous.some(row => row.status === 'pending') || (legacy ? !claimable(legacy) : !times.some(slot => claimable(previous.find(row => row.slot === slot))))) return null;
+        }
+      }
       const service = new HabitService(db, { id: currentUser.id, discordId: currentUser.discordId, username: currentUser.username, displayName: currentUser.globalName ?? currentUser.username, avatarUrl: null, timezone: currentUser.timezone }, timestamp);
       service.sync();
       // Avoid sending an artificial "today" after a backwards timezone change.
@@ -37,7 +49,7 @@ export async function sendDueReminders(db: AppDatabase, config: ReminderConfig,
       const remaining = service.list().filter(habit => { const day = service.day(habit.id, service.today); return day.due && !day.complete; }).length;
       return remaining ? { date: service.today, remaining, timezone: currentUser.timezone, times, entries: entriesForDate(prefs, service.today) } : null;
     }
-    const initial = due(); if (!initial) continue;
+    const initial = due(true); if (!initial) continue;
     const claims = db.transaction(tx => {
       // A crashed/aborted send must not block later times indefinitely.
       tx.update(reminderDeliveries).set({ status: "uncertain" }).where(and(eq(reminderDeliveries.userId, user.id), eq(reminderDeliveries.status, "pending"), lt(reminderDeliveries.updatedAt, now() - 60000))).run();