From 0dc3eb188430d30a169c698965f4d1f19f268378 Mon Sep 17 00:00:00 2001
From: Jannis Braun <151788261+TheZwiss@users.noreply.github.com>
Date: Fri, 20 Mar 2026 19:03:35 +0100
Subject: [PATCH] fix: notify displaced tab when user joins voice from another
 session

When a user joins a voice channel while already connected from another
tab, the server now sends a 'displaced' reason on voice_disconnected.
The client tears down LiveKit and shows an informational toast.
---
 packages/server/src/ws/events.ts       |  8 ++++++++
 packages/shared/src/types.ts           |  2 +-
 packages/web/src/hooks/useWebSocket.ts | 11 ++++++++++-
 3 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/packages/server/src/ws/events.ts b/packages/server/src/ws/events.ts
index f14cf87c..44171d64 100644
--- a/packages/server/src/ws/events.ts
+++ b/packages/server/src/ws/events.ts
@@ -537,6 +537,14 @@ function handleVoiceJoin(event: Record<string, unknown>, userId: string): void {
   const left = connectionManager.leaveCurrentRoom(userId);
   if (left) {
     broadcastRoomLeave(left.roomId, left.room, userId);
+
+    // Notify all of the user's tabs so the displaced tab tears down LiveKit
+    connectionManager.sendToUser(userId, {
+      type: 'voice_disconnected',
+      userId,
+      channelId: left.roomId,
+      reason: 'displaced',
+    });
   }
 
   // Cancel any ringing DM rooms where this user is the caller
diff --git a/packages/shared/src/types.ts b/packages/shared/src/types.ts
index 8fb36614..0e3e6d97 100644
--- a/packages/shared/src/types.ts
+++ b/packages/shared/src/types.ts
@@ -330,7 +330,7 @@ export type ServerEvent =
   | { type: 'voice_space_deafened'; userId: string; channelId: string; spaceId: string; deafened: boolean }
   | { type: 'voice_permission_muted'; userId: string; spaceId: string; muted: boolean }
   | { type: 'voice_moved'; userId: string; oldChannelId: string; newChannelId: string }
-  | { type: 'voice_disconnected'; userId: string; channelId: string }
+  | { type: 'voice_disconnected'; userId: string; channelId: string; reason?: 'displaced' }
   | { type: 'user_updated'; user: User }
   | { type: 'member_banned'; spaceId: string; reason: string | null }
   | { type: 'category_created'; category: ChannelCategory; spaceId: string }
diff --git a/packages/web/src/hooks/useWebSocket.ts b/packages/web/src/hooks/useWebSocket.ts
index b2612a9f..075f9555 100644
--- a/packages/web/src/hooks/useWebSocket.ts
+++ b/packages/web/src/hooks/useWebSocket.ts
@@ -9,6 +9,8 @@ import type { ServerEvent, ClientEvent, ActiveCallInfo } from '@backspace/shared
 import { resolveAssetUrl, normalizeUserAssets, normalizeMessageAssets } from '../utils/assetUrls';
 import { broadcastVoiceStatus, broadcastDeafenViaLiveKit } from '../utils/voice';
 import { registerSelfId } from '../utils/identity';
+import { getActiveRoom } from './useLiveKit';
+import { useUIStore } from '../stores/uiStore';
 
 // ─── Connection state ─────────────────────────────────────────────────────────
 
@@ -428,7 +430,14 @@ function handleEvent(origin: string, event: ServerEvent): void {
     case 'voice_disconnected': {
       const myDisconnectId = isHome ? useAuthStore.getState().user?.id : getMyUserIdForOrigin(origin);
       if (event.userId === myDisconnectId) {
-        useVoiceStore.getState().handleForceDisconnect();
+        const { currentVoiceChannelId } = useVoiceStore.getState();
+        if (event.channelId === currentVoiceChannelId) {
+          useVoiceStore.getState().handleForceDisconnect();
+          getActiveRoom()?.disconnect();
+          if (event.reason === 'displaced') {
+            useUIStore.getState().addToast('Voice disconnected — joined from another session', 'info');
+          }
+        }
       }
       break;
     }