From bcd95da21f75ff346f2256d3502df16b5598f2d6 Mon Sep 17 00:00:00 2001
From: lebaudantoine <lebaud.antoine131@gmail.com>
Date: Sun, 23 Aug 2026 17:14:17 +0200
Subject: [PATCH] =?UTF-8?q?=F0=9F=90=9B(frontend)=20make=20the=20device-in?=
 =?UTF-8?q?-use=20logic=20race-free?=
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The device-in-use logic could race when multiple detection events
fired close together (e.g. rapid mic/cam toggles or several devices
becoming busy at once), leading to inconsistent store state.

Refactor the flow so all updates go through a serialized path,
removing the race conditions and keeping the in-use state
consistent regardless of event ordering.
---
 .../rooms/hooks/useWatchDeviceReleased.ts      | 18 +++++++++++++-----
 .../rooms/livekit/hooks/useJoinTracks.ts       |  3 ++-
 2 files changed, 15 insertions(+), 6 deletions(-)

diff --git a/src/frontend/src/features/rooms/hooks/useWatchDeviceReleased.ts b/src/frontend/src/features/rooms/hooks/useWatchDeviceReleased.ts
index 8329b188..889ca0d3 100644
--- a/src/frontend/src/features/rooms/hooks/useWatchDeviceReleased.ts
+++ b/src/frontend/src/features/rooms/hooks/useWatchDeviceReleased.ts
@@ -36,10 +36,18 @@ function useWatchKind(
 
   useEffect(() => {
     if (!inUse) return
-    const id = setInterval(
-      () => void probeDeviceReleased(kind, selectedDeviceId || undefined),
-      RETRY_INTERVAL_MS
-    )
-    return () => clearInterval(id)
+    let stopped = false
+    let timer: number | undefined
+    const tick = async () => {
+      await probeDeviceReleased(kind, selectedDeviceId || undefined)
+      if (!stopped) {
+        timer = window.setTimeout(tick, RETRY_INTERVAL_MS)
+      }
+    }
+    timer = window.setTimeout(tick, RETRY_INTERVAL_MS)
+    return () => {
+      stopped = true
+      window.clearTimeout(timer)
+    }
   }, [kind, inUse, selectedDeviceId])
 }
diff --git a/src/frontend/src/features/rooms/livekit/hooks/useJoinTracks.ts b/src/frontend/src/features/rooms/livekit/hooks/useJoinTracks.ts
index 1a60c132..40ef40be 100644
--- a/src/frontend/src/features/rooms/livekit/hooks/useJoinTracks.ts
+++ b/src/frontend/src/features/rooms/livekit/hooks/useJoinTracks.ts
@@ -151,14 +151,15 @@ function useLocalTrack<T extends LocalAudioTrack | LocalVideoTrack>({
     let cancelled = false
     create()
       .then((newTrack) => {
-        noteDeviceReady(permissionKind)
         if (cancelled) {
           newTrack.stop()
           return
         }
+        noteDeviceReady(permissionKind)
         setTrack(newTrack)
       })
       .catch((error) => {
+        if (cancelled) return
         onMediaPermissionError(
           error as Error,
           permissionKind,