feat(calendar): add reminder functionality for events with notifications

server/config/database.js

@@ -513,6 +513,12 @@ export async function initDatabase() {
   if (!(await db.columnExists('calendar_events', 'federated_join_url'))) {
     await db.exec('ALTER TABLE calendar_events ADD COLUMN federated_join_url TEXT DEFAULT NULL');
   }
+  if (!(await db.columnExists('calendar_events', 'reminder_minutes'))) {
+    await db.exec('ALTER TABLE calendar_events ADD COLUMN reminder_minutes INTEGER DEFAULT NULL');
+  }
+  if (!(await db.columnExists('calendar_events', 'reminder_sent_at'))) {
+    await db.exec('ALTER TABLE calendar_events ADD COLUMN reminder_sent_at DATETIME DEFAULT NULL');
+  }
 
   // Calendar invitations (federated calendar events that must be accepted first)
   if (isPostgres) {

server/index.js

@@ -18,6 +18,7 @@ import caldavRoutes from './routes/caldav.js';
 import notificationRoutes from './routes/notifications.js';
 import oauthRoutes from './routes/oauth.js';
 import { startFederationSync } from './jobs/federationSync.js';
+import { startCalendarReminders } from './jobs/calendarReminders.js';
 
 const __filename = fileURLToPath(import.meta.url);
 const __dirname = path.dirname(__filename);
@@ -93,6 +94,8 @@ async function start() {
 
   // Start periodic federation sync job (checks remote room settings every 60s)
   startFederationSync();
+  // Start calendar reminder job (sends in-app + browser notifications before events)
+  startCalendarReminders();
 }
 
 start().catch(err => {

server/jobs/calendarReminders.js

@@ -0,0 +1,90 @@
+import { getDb } from '../config/database.js';
+import { log } from '../config/logger.js';
+import { createNotification } from '../config/notifications.js';
+
+const CHECK_INTERVAL_MS = 60_000; // every minute
+
+let timer = null;
+
+/**
+ * Check for upcoming calendar events that need a reminder notification fired.
+ * Runs every minute. Updates `reminder_sent_at` after firing so reminders
+ * are never sent twice. Also resets `reminder_sent_at` to NULL when
+ * start_time or reminder_minutes is changed (handled in calendar route).
+ */
+async function runCheck() {
+  try {
+    const db = getDb();
+
+    // Fetch all events that have a reminder configured and haven't been sent yet
+    const pending = await db.all(`
+      SELECT ce.id, ce.uid, ce.title, ce.start_time, ce.reminder_minutes, ce.user_id,
+             ce.room_uid, ce.color
+      FROM calendar_events ce
+      WHERE ce.reminder_minutes IS NOT NULL
+        AND ce.reminder_sent_at IS NULL
+    `);
+
+    if (pending.length === 0) return;
+
+    const now = new Date();
+    const toFire = pending.filter(ev => {
+      const start = new Date(ev.start_time);
+      // Don't fire reminders for events that started more than 10 minutes ago (server downtime tolerance)
+      if (start < new Date(now.getTime() - 10 * 60_000)) return false;
+      const reminderTime = new Date(start.getTime() - ev.reminder_minutes * 60_000);
+      return reminderTime <= now;
+    });
+
+    for (const ev of toFire) {
+      try {
+        // Mark as sent immediately to prevent double-fire even if notification creation fails
+        await db.run(
+          'UPDATE calendar_events SET reminder_sent_at = ? WHERE id = ?',
+          [now.toISOString(), ev.id],
+        );
+
+        const start = new Date(ev.start_time);
+        const timeStr = start.toLocaleTimeString([], { hour: '2-digit', minute: '2-digit' });
+        const dateStr = start.toLocaleDateString([], { day: 'numeric', month: 'short' });
+        const body = `${dateStr} · ${timeStr}`;
+        const link = '/calendar';
+
+        // Notify the owner
+        await createNotification(ev.user_id, 'calendar_reminder', ev.title, body, link);
+
+        // Notify all accepted share users as well
+        const shares = await db.all(
+          'SELECT user_id FROM calendar_event_shares WHERE event_id = ?',
+          [ev.id],
+        );
+        for (const { user_id } of shares) {
+          await createNotification(user_id, 'calendar_reminder', ev.title, body, link);
+        }
+
+        log.server.info(`Calendar reminder fired for event ${ev.uid} (id=${ev.id})`);
+      } catch (evErr) {
+        log.server.error(`Calendar reminder failed for event ${ev.id}: ${evErr.message}`);
+      }
+    }
+  } catch (err) {
+    log.server.error(`Calendar reminder job error: ${err.message}`);
+  }
+}
+
+export function startCalendarReminders() {
+  if (timer) return;
+  // Slight delay on startup so DB is fully ready
+  setTimeout(() => {
+    runCheck();
+    timer = setInterval(runCheck, CHECK_INTERVAL_MS);
+  }, 5_000);
+  log.server.info('Calendar reminder job started');
+}
+
+export function stopCalendarReminders() {
+  if (timer) {
+    clearInterval(timer);
+    timer = null;
+  }
+}

server/routes/caldav.js

@@ -144,6 +144,15 @@ function eventToICS(event, base, user) {
   if (joinUrl) {
     lines.push(`X-REDLIGHT-JOIN-URL:${escapeICS(joinUrl)}`);
   }
+  if (event.reminder_minutes) {
+    lines.push(
+      'BEGIN:VALARM',
+      'ACTION:DISPLAY',
+      `DESCRIPTION:${escapeICS(event.title)}`,
+      `TRIGGER:-PT${event.reminder_minutes}M`,
+      'END:VALARM',
+    );
+  }
   lines.push('END:VEVENT', 'END:VCALENDAR');
   return lines.map(foldICSLine).join('\r\n');
 }

server/routes/calendar.js

@@ -19,6 +19,9 @@ const router = Router();
 // Allowlist for CSS color values - only permits hsl(), hex (#rgb/#rrggbb) and plain names
 const SAFE_COLOR_RE = /^(?:#[0-9a-fA-F]{3,8}|hsl\(\d{1,3},\s*\d{1,3}%,\s*\d{1,3}%\)|[a-zA-Z]{1,30})$/;
 
+// Allowed reminder intervals in minutes
+const VALID_REMINDERS = new Set([5, 15, 30, 60, 120, 1440]);
+
 // Rate limit for federation calendar receive
 const calendarFederationLimiter = rateLimit({
   windowMs: 15 * 60 * 1000,
@@ -117,7 +120,7 @@ router.get('/events/:id', authenticateToken, async (req, res) => {
 // ── POST /api/calendar/events — Create event ────────────────────────────────
 router.post('/events', authenticateToken, async (req, res) => {
   try {
-    const { title, description, start_time, end_time, room_uid, color } = req.body;
+    const { title, description, start_time, end_time, room_uid, color, reminder_minutes } = req.body;
 
     if (!title || !title.trim()) return res.status(400).json({ error: 'Title is required' });
     if (!start_time || !end_time) return res.status(400).json({ error: 'Start and end time are required' });
@@ -146,9 +149,12 @@ router.post('/events', authenticateToken, async (req, res) => {
     }
 
     const uid = crypto.randomBytes(12).toString('hex');
+    const validReminder = (reminder_minutes != null && VALID_REMINDERS.has(Number(reminder_minutes)))
+      ? Number(reminder_minutes) : null;
+
     const result = await db.run(`
-      INSERT INTO calendar_events (uid, title, description, start_time, end_time, room_uid, user_id, color)
+      INSERT INTO calendar_events (uid, title, description, start_time, end_time, room_uid, user_id, color, reminder_minutes)
-      VALUES (?, ?, ?, ?, ?, ?, ?, ?)
+      VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?)
     `, [
       uid,
       title.trim(),
@@ -158,6 +164,7 @@ router.post('/events', authenticateToken, async (req, res) => {
       room_uid || null,
       req.user.id,
       color || '#6366f1',
+      validReminder,
     ]);
 
     const event = await db.get('SELECT * FROM calendar_events WHERE id = ?', [result.lastInsertRowid]);
@@ -175,7 +182,7 @@ router.put('/events/:id', authenticateToken, async (req, res) => {
     const event = await db.get('SELECT * FROM calendar_events WHERE id = ? AND user_id = ?', [req.params.id, req.user.id]);
     if (!event) return res.status(404).json({ error: 'Event not found or no permission' });
 
-    const { title, description, start_time, end_time, room_uid, color } = req.body;
+    const { title, description, start_time, end_time, room_uid, color, reminder_minutes } = req.body;
 
     if (title && title.length > 200) return res.status(400).json({ error: 'Title must not exceed 200 characters' });
     if (description && description.length > 5000) return res.status(400).json({ error: 'Description must not exceed 5000 characters' });
@@ -197,6 +204,13 @@ router.put('/events/:id', authenticateToken, async (req, res) => {
       if (!room) return res.status(400).json({ error: 'Linked room not found' });
     }
 
+    const validReminder = (reminder_minutes !== undefined)
+      ? ((reminder_minutes != null && VALID_REMINDERS.has(Number(reminder_minutes))) ? Number(reminder_minutes) : null)
+      : undefined;
+    // Reset reminder_sent_at when start_time or reminder_minutes changes so the job re-fires
+    const resetReminder = (start_time !== undefined && start_time !== event.start_time)
+      || (reminder_minutes !== undefined && validReminder !== event.reminder_minutes);
+
     await db.run(`
       UPDATE calendar_events SET
         title = COALESCE(?, title),
@@ -205,6 +219,8 @@ router.put('/events/:id', authenticateToken, async (req, res) => {
         end_time = COALESCE(?, end_time),
         room_uid = ?,
         color = COALESCE(?, color),
+        reminder_minutes = COALESCE(?, reminder_minutes),
+        reminder_sent_at = ${resetReminder ? 'NULL' : 'reminder_sent_at'},
         updated_at = CURRENT_TIMESTAMP
       WHERE id = ?
     `, [
@@ -214,6 +230,7 @@ router.put('/events/:id', authenticateToken, async (req, res) => {
       end_time || null,
       room_uid !== undefined ? (room_uid || null) : event.room_uid,
       color || null,
+      validReminder !== undefined ? validReminder : null,
       req.params.id,
     ]);
 
@@ -686,6 +703,15 @@ function generateICS(event, location, prodIdDomain) {
     ics.push(`ORGANIZER;CN=${escapeICS(event.organizer_name)}:mailto:${event.organizer_email}`);
   }
 
+  if (event.reminder_minutes) {
+    ics.push(
+      'BEGIN:VALARM',
+      'ACTION:DISPLAY',
+      `DESCRIPTION:Reminder: ${escapeICS(event.title)}`,
+      `TRIGGER:-PT${event.reminder_minutes}M`,
+      'END:VALARM',
+    );
+  }
   ics.push('END:VEVENT', 'END:VCALENDAR');
   return ics.join('\r\n');
 }

src/contexts/NotificationContext.jsx

@@ -77,6 +77,15 @@ export function NotificationProvider({ children }) {
         seenIds.current.add(n.id);
         const icon = notificationIcon(n.type);
         toast(`${icon} ${n.title}`, { duration: 5000 });
+        // Browser notification for calendar reminders
+        if (n.type === 'calendar_reminder' && 'Notification' in window) {
+          const fire = () => new Notification(n.title, { body: n.body || '', icon: '/favicon.ico' });
+          if (Notification.permission === 'granted') {
+            fire();
+          } else if (Notification.permission !== 'denied') {
+            Notification.requestPermission().then(p => { if (p === 'granted') fire(); });
+          }
+        }
       });
     } catch {
       /* silent – server may not be reachable */
@@ -166,6 +175,7 @@ function notificationIcon(type) {
     case 'room_share_added':       return '🔗';
     case 'room_share_removed':     return '🚫';
     case 'federation_invite_received': return '📩';
+    case 'calendar_reminder':      return '🔔';
     default:                       return '🔔';
   }
 }

src/i18n/de.json

@@ -510,6 +510,14 @@
     "linkedRoom": "Verknüpfter Raum",
     "noRoom": "Kein Raum (kein Videomeeting)",
     "linkedRoomHint": "Verknüpfe einen Raum, um die Beitritts-URL automatisch ins Event einzufügen.",
+    "reminderLabel": "Erinnerung",
+    "reminderNone": "Keine Erinnerung",
+    "reminder5": "5 Minuten vorher",
+    "reminder15": "15 Minuten vorher",
+    "reminder30": "30 Minuten vorher",
+    "reminder60": "1 Stunde vorher",
+    "reminder120": "2 Stunden vorher",
+    "reminder1440": "1 Tag vorher",
     "timezone": "Zeitzone",
     "color": "Farbe",
     "eventCreated": "Event erstellt!",

src/i18n/en.json

@@ -510,6 +510,14 @@
     "linkedRoom": "Linked Room",
     "noRoom": "No room (no video meeting)",
     "linkedRoomHint": "Link a room to automatically include the join-URL in the event.",
+    "reminderLabel": "Reminder",
+    "reminderNone": "No reminder",
+    "reminder5": "5 minutes before",
+    "reminder15": "15 minutes before",
+    "reminder30": "30 minutes before",
+    "reminder60": "1 hour before",
+    "reminder120": "2 hours before",
+    "reminder1440": "1 day before",
     "timezone": "Timezone",
     "color": "Color",
     "eventCreated": "Event created!",

src/pages/Calendar.jsx

@@ -1,6 +1,6 @@
 import { useState, useEffect, useMemo } from 'react';
 import {
-  ChevronLeft, ChevronRight, Plus, Clock, Video,
+  ChevronLeft, ChevronRight, Plus, Clock, Video, Bell,
   Loader2, Download, Share2, Globe, Trash2, Edit, X, UserPlus, Send, ExternalLink,
 } from 'lucide-react';
 import api from '../services/api';
@@ -32,7 +32,7 @@ export default function Calendar() {
   // Create/Edit form
   const [form, setForm] = useState({
     title: '', description: '', start_time: '', end_time: '',
-    room_uid: '', color: '#6366f1',
+    room_uid: '', color: '#6366f1', reminder_minutes: null,
   });
   const [saving, setSaving] = useState(false);
 
@@ -157,7 +157,7 @@ export default function Calendar() {
       title: '', description: '',
       start_time: toLocalDateTimeStr(start),
       end_time: toLocalDateTimeStr(end),
-      room_uid: '', color: '#6366f1',
+      room_uid: '', color: '#6366f1', reminder_minutes: null,
     });
     setEditingEvent(null);
     setShowCreate(true);
@@ -171,6 +171,7 @@ export default function Calendar() {
       end_time: toLocalDateTimeStr(new Date(ev.end_time)),
       room_uid: ev.room_uid || '',
       color: ev.color || '#6366f1',
+      reminder_minutes: ev.reminder_minutes ?? null,
     });
     setEditingEvent(ev);
     setShowDetail(null);
@@ -494,7 +495,10 @@ export default function Calendar() {
                         className="text-xs px-2 py-1.5 rounded text-white font-medium cursor-pointer hover:opacity-80 transition-opacity"
                         style={{ backgroundColor: ev.color || '#6366f1' }}
                       >
-                        <div className="truncate">{ev.title}</div>
+                        <div className="flex items-center gap-1 truncate">
+                          {ev.reminder_minutes && <Bell size={9} className="flex-shrink-0 opacity-70" />}
+                          <span className="truncate">{ev.title}</span>
+                        </div>
                         <div className="opacity-80 text-[10px]">{formatTime(ev.start_time)} - {formatTime(ev.end_time)}</div>
                       </div>
                     ))}
@@ -570,6 +574,26 @@ export default function Calendar() {
               <p className="text-xs text-th-text-s mt-1">{t('calendar.linkedRoomHint')}</p>
             </div>
 
+            <div>
+              <label className="block text-sm font-medium text-th-text mb-1.5">{t('calendar.reminderLabel')}</label>
+              <div className="relative">
+                <Bell size={15} className="absolute left-3 top-1/2 -translate-y-1/2 text-th-text-s pointer-events-none" />
+                <select
+                  value={form.reminder_minutes ?? ''}
+                  onChange={e => setForm({ ...form, reminder_minutes: e.target.value === '' ? null : Number(e.target.value) })}
+                  className="input-field pl-9"
+                >
+                  <option value="">{t('calendar.reminderNone')}</option>
+                  <option value="5">{t('calendar.reminder5')}</option>
+                  <option value="15">{t('calendar.reminder15')}</option>
+                  <option value="30">{t('calendar.reminder30')}</option>
+                  <option value="60">{t('calendar.reminder60')}</option>
+                  <option value="120">{t('calendar.reminder120')}</option>
+                  <option value="1440">{t('calendar.reminder1440')}</option>
+                </select>
+              </div>
+            </div>
+
             <div>
               <label className="block text-sm font-medium text-th-text mb-1.5">{t('calendar.color')}</label>
               <div className="flex gap-2">