web: add notification sound toggle and complete notifications module

web/src/hooks/useRealtime.ts

@@ -448,6 +448,9 @@ function maybeShowBrowserNotification(
   const titleBase = chat?.display_title || chat?.title || "New message";
   const title = isMention ? `@ Mention in ${titleBase}` : titleBase;
   const preview = buildNotificationPreview(message, prefs.messagePreview);
+  if (prefs.notificationSound) {
+    playNotificationSound();
+  }
 
   void (async () => {
     const shownViaSw = await showNotificationViaServiceWorker({
@@ -492,3 +495,34 @@ function hasMentionForUser(text: string | null, username: string | null): boolea
     }
   }
 }
+
+function playNotificationSound(): void {
+  if (typeof window === "undefined") {
+    return;
+  }
+  const AudioContextCtor =
+    window.AudioContext ||
+    (window as unknown as { webkitAudioContext?: typeof AudioContext }).webkitAudioContext;
+  if (!AudioContextCtor) {
+    return;
+  }
+  try {
+    const context = new AudioContextCtor();
+    const oscillator = context.createOscillator();
+    const gain = context.createGain();
+    oscillator.type = "sine";
+    oscillator.frequency.setValueAtTime(880, context.currentTime);
+    gain.gain.setValueAtTime(0.0001, context.currentTime);
+    gain.gain.exponentialRampToValueAtTime(0.08, context.currentTime + 0.01);
+    gain.gain.exponentialRampToValueAtTime(0.0001, context.currentTime + 0.16);
+    oscillator.connect(gain);
+    gain.connect(context.destination);
+    oscillator.start();
+    oscillator.stop(context.currentTime + 0.17);
+    oscillator.onended = () => {
+      void context.close();
+    };
+  } catch {
+    return;
+  }
+}