fix(llc): fix camera flip (#1094)

* webrtc m137 wip

* fix camera flip

* tweaks

* changelog

Author: Brazol

packages/stream_video/CHANGELOG.md

@@ -5,6 +5,7 @@
 - [Web] Fixed changing the output audio device during the call.
 - [Android/iOS] Fixed an issue where screen sharing was not stopped correctly when canceled via the system UI on Android or iOS.
 - [iOS] Improved broadcast extension handling — the app now waits for the broadcast picker selection before actually starting screen sharing.
+- Resolved an issue where the camera wouldn’t flip correctly if the back camera was selected initially.
 - Fixed an issue where `callMembers` collection wasn't reflecting the actual members list after starting the call session.
 
 ✅ Added

packages/stream_video/lib/src/call/call.dart

@@ -2791,10 +2791,13 @@ class Call {
 
     if (result.isSuccess) {
       _connectOptions = connectOptions.copyWith(videoInputDevice: device);
-      _stateManager.participantSetVideoInputDevice(device: device);
+      _stateManager.participantSetVideoInputDevice(
+        device: device,
+        track: result.getDataOrNull()!,
+      );
     }
 
-    return result;
+    return result.map((_) => none);
   }
 
   Future<Result<None>> setCameraEnabled({
@@ -2832,11 +2835,17 @@ class Call {
         iOSMultitaskingCameraAccessEnabled: multitaskingEnabled,
       );
 
+      var facingMode = constraints?.facingMode;
+      if (facingMode == null && result.getDataOrNull() is RtcLocalCameraTrack) {
+        final track = result.getDataOrNull()! as RtcLocalCameraTrack;
+        facingMode = track.mediaConstraints.facingMode;
+      }
+
       _connectOptions = _connectOptions.copyWith(
         camera: enabled
             ? TrackOption.enabled(constraints: constraints)
             : TrackOption.disabled(),
-        cameraFacingMode: constraints?.facingMode ?? FacingMode.user,
+        cameraFacingMode: facingMode ?? _connectOptions.cameraFacingMode,
       );
     }
 

packages/stream_video/lib/src/call/session/call_session.dart

@@ -1110,14 +1110,15 @@ class CallSession extends Disposable {
     return result;
   }
 
-  Future<Result<None>> setVideoInputDevice(RtcMediaDevice device) async {
+  Future<Result<RtcLocalTrack<CameraConstraints>>> setVideoInputDevice(
+    RtcMediaDevice device,
+  ) async {
     final rtcManager = this.rtcManager;
     if (rtcManager == null) {
       return Result.error('Unable to set video input, Call not connected');
     }
 
-    final result = await rtcManager.setVideoInputDevice(device: device);
-    return result.map((_) => none);
+    return rtcManager.setVideoInputDevice(device: device);
   }
 
   Future<Result<None>> setCameraPosition(CameraPosition position) async {

packages/stream_video/lib/src/call/state/mixins/state_participant_mixin.dart

@@ -7,8 +7,10 @@ import '../../../models/call_track_state.dart';
 import '../../../models/viewport_visibility.dart';
 import '../../../sfu/data/models/sfu_track_type.dart';
 import '../../../webrtc/media/constraints/camera_position.dart';
+import '../../../webrtc/media/media_constraints.dart';
 import '../../../webrtc/model/rtc_video_dimension.dart';
 import '../../../webrtc/rtc_media_device/rtc_media_device.dart';
+import '../../../webrtc/rtc_track/rtc_local_track.dart';
 
 final _logger = taggedLogger(tag: 'SV:CoordNotifier');
 
@@ -246,7 +248,13 @@ mixin StateParticipantMixin on StateNotifier<CallState> {
 
   void participantSetVideoInputDevice({
     required RtcMediaDevice device,
+    required RtcLocalTrack<CameraConstraints> track,
   }) {
+    final facingMode = track.mediaConstraints.facingMode;
+    final cameraPosition = facingMode == FacingMode.user
+        ? CameraPosition.front
+        : CameraPosition.back;
+
     state = state.copyWith(
       videoInputDevice: device,
       callParticipants: state.callParticipants.map((participant) {
@@ -259,7 +267,7 @@ mixin StateParticipantMixin on StateNotifier<CallState> {
                 SfuTrackType.video: trackState.copyWith(
                   sourceDevice: device,
                   // reset camera position to default
-                  cameraPosition: CameraPosition.front,
+                  cameraPosition: cameraPosition,
                 ),
               },
             );

packages/stream_video/lib/src/webrtc/rtc_track/rtc_local_track.dart

@@ -71,12 +71,21 @@ class RtcLocalTrack<T extends MediaConstraints> extends RtcTrack {
       throw VideoException('No camera track found');
     }
 
+    final detectedFacingMode = _detectFacingModeFromTrack(
+      videoTrack,
+      fallbackFacingMode: constraints.facingMode,
+    );
+
+    final updatedConstraints = constraints.copyWith(
+      facingMode: detectedFacingMode,
+    );
+
     final track = RtcLocalTrack(
       trackIdPrefix: trackIdPrefix,
       trackType: SfuTrackType.video,
       mediaStream: stream,
       mediaTrack: videoTrack,
-      mediaConstraints: constraints,
+      mediaConstraints: updatedConstraints,
     );
 
     return track;
@@ -254,6 +263,46 @@ class RtcLocalTrack<T extends MediaConstraints> extends RtcTrack {
 
 const _cameraTag = 'SV:RtcLocalCameraTrack';
 
+/// Detects the facing mode from a video track.
+FacingMode _detectFacingModeFromTrack(
+  rtc.MediaStreamTrack videoTrack, {
+  required FacingMode fallbackFacingMode,
+  String? deviceLabel,
+}) {
+  try {
+    final settings = videoTrack.getSettings();
+    final settingsFacingMode = settings['facingMode'];
+
+    if (settingsFacingMode != null) {
+      return FacingMode.fromAlias(settingsFacingMode);
+    } else {
+      // Try to infer from device label if available
+      if (deviceLabel != null) {
+        return _inferFacingModeFromLabel(deviceLabel, fallbackFacingMode);
+      }
+    }
+  } catch (e) {
+    if (deviceLabel != null) {
+      return _inferFacingModeFromLabel(deviceLabel, fallbackFacingMode);
+    }
+  }
+
+  return fallbackFacingMode;
+}
+
+FacingMode _inferFacingModeFromLabel(String label, FacingMode fallback) {
+  final lowerLabel = label.toLowerCase();
+  if (lowerLabel.contains('back') ||
+      lowerLabel.contains('rear') ||
+      lowerLabel.contains('environment')) {
+    return FacingMode.environment;
+  } else if (lowerLabel.contains('front')) {
+    return FacingMode.user;
+  }
+
+  return fallback;
+}
+
 extension RtcLocalCameraTrackHardwareExt on RtcLocalCameraTrack {
   Future<RtcLocalCameraTrack> flipCamera() async {
     streamLog.i(_cameraTag, () => 'Flipping camera');
@@ -312,16 +361,12 @@ extension RtcLocalCameraTrackHardwareExt on RtcLocalCameraTrack {
       ),
     );
 
-    // Default to user facing mode.
-    var facingMode = FacingMode.user;
-
-    // Use the facingMode from the track settings if available.
-    try {
-      final settings = updatedTrack.mediaTrack.getSettings();
-      facingMode = FacingMode.fromAlias(settings['facingMode']);
-    } catch (e) {
-      // ignore
-    }
+    // Detect the actual facing mode from the track.
+    final facingMode = _detectFacingModeFromTrack(
+      updatedTrack.mediaTrack,
+      fallbackFacingMode: mediaConstraints.facingMode,
+      deviceLabel: device.label,
+    );
 
     return updatedTrack.copyWith(
       mediaConstraints: updatedTrack.mediaConstraints.copyWith(

packages/stream_video_flutter/CHANGELOG.md

@@ -5,10 +5,11 @@
 - [Web] Fixed changing the output audio device during the call.
 - [Android/iOS] Fixed an issue where screen sharing was not stopped correctly when canceled via the system UI on Android or iOS.
 - [iOS] Improved broadcast extension handling — the app now waits for the broadcast picker selection before actually starting screen sharing.
+- Resolved an issue where the camera wouldn’t flip correctly if the back camera was selected initially.
+- Fixed an issue where `callMembers` collection wasn't reflecting the actual members list after starting the call session.
 
 ✅ Added
 - [Web] Added `checkIfAudioOutputChangeSupported()` to the `Call` class to check whether the browser supports changing the audio output device.
-=======
 
 ## 0.11.1
 

packages/stream_video_flutter/lib/src/call_screen/lobby_video.dart

@@ -149,7 +149,9 @@ class _StreamLobbyVideoState extends State<StreamLobbyVideo> {
                       children: [
                         if (cameraEnabled)
                           VideoTrackRenderer(
-                            mirror: true,
+                            mirror:
+                                _cameraTrack!.mediaConstraints.facingMode ==
+                                FacingMode.user,
                             videoTrack: _cameraTrack!,
                             placeholderBuilder: placeHolderBuilder,
                           )