Fix/track not stop stats monitor correctly (#306)

* feat: add preferCurrentTab support for flutter web.

* fix: Stop Stats monitor correctly when Track.onDispose.

lib/src/track/local/audio.dart

@@ -33,10 +33,10 @@ class LocalAudioTrack extends LocalTrack
   AudioSenderStats? prevStats;
 
   @override
-  Future<void> monitorSender() async {
+  Future<bool> monitorStats() async {
-    if (sender == null) {
+    if (sender == null || events.isDisposed) {
       _currentBitrate = 0;
-      return;
+      return false;
     }
     final stats = await getSenderStats();
 
@@ -47,6 +47,7 @@ class LocalAudioTrack extends LocalTrack
     }
 
     prevStats = stats;
+    return true;
   }
 
   Future<AudioSenderStats?> getSenderStats() async {

lib/src/track/local/local.dart

@@ -17,7 +17,6 @@ import '../../types/other.dart';
 import '../options.dart';
 import '../remote/audio.dart';
 import '../remote/video.dart';
-import '../stats.dart';
 import '../track.dart';
 import 'audio.dart';
 import 'video.dart';
@@ -196,7 +195,6 @@ abstract class LocalTrack extends Track {
     }
 
     logger.fine('$objectId.publish()');
-    startMonitor();
     _published = true;
     return true;
   }
@@ -210,26 +208,7 @@ abstract class LocalTrack extends Track {
     }
 
     logger.fine('$objectId.unpublish()');
-    stopMonitor();
     _published = false;
     return true;
   }
-
-  Timer? _monitorTimer;
-
-  Future<void> monitorSender();
-
-  @internal
-  void startMonitor() {
-    _monitorTimer ??=
-        Timer.periodic(const Duration(milliseconds: monitorFrequency), (_) {
-      monitorSender();
-    });
-  }
-
-  @internal
-  void stopMonitor() {
-    _monitorTimer?.cancel();
-    _monitorTimer = null;
-  }
 }

lib/src/track/local/video.dart

@@ -23,17 +23,17 @@ class LocalVideoTrack extends LocalTrack with VideoTrack {
   final Map<String, num> _bitrateFoLayers = {};
 
   @override
-  Future<void> monitorSender() async {
+  Future<bool> monitorStats() async {
-    if (sender == null) {
+    if (sender == null || events.isDisposed) {
       _currentBitrate = 0;
-      return;
+      return false;
     }
     List<VideoSenderStats> stats = [];
     try {
       stats = await getSenderStats();
     } catch (e) {
       logger.warning('Failed to get sender stats: $e');
-      return;
+      return false;
     }
     Map<String, VideoSenderStats> statsMap = {};
 
@@ -58,6 +58,7 @@ class LocalVideoTrack extends LocalTrack with VideoTrack {
     }
 
     prevStats = statsMap;
+    return true;
   }
 
   Future<List<VideoSenderStats>> getSenderStats() async {

lib/src/track/remote/audio.dart

@@ -66,10 +66,10 @@ class RemoteAudioTrack extends RemoteTrack
   get currentBitrate => _currentBitrate;
 
   @override
-  Future<void> monitorReceiver() async {
+  Future<bool> monitorStats() async {
-    if (receiver == null) {
+    if (receiver == null && events.isDisposed) {
       _currentBitrate = 0;
-      return;
+      return false;
     }
     final stats = await getReceiverStats();
 
@@ -80,6 +80,7 @@ class RemoteAudioTrack extends RemoteTrack
     }
 
     prevStats = stats;
+    return true;
   }
 
   Future<AudioReceiverStats?> getReceiverStats() async {

lib/src/track/remote/remote.dart

@@ -1,11 +1,9 @@
 import 'dart:async';
 
 import 'package:flutter_webrtc/flutter_webrtc.dart' as rtc;
-import 'package:meta/meta.dart';
 
 import '../../proto/livekit_models.pb.dart' as lk_models;
 import '../../types/other.dart';
-import '../stats.dart';
 import '../track.dart';
 
 abstract class RemoteTrack extends Track {
@@ -25,7 +23,6 @@ abstract class RemoteTrack extends Track {
     final didStart = await super.start();
     if (didStart) {
       await enable();
-      startMonitor();
     }
     return didStart;
   }
@@ -36,25 +33,6 @@ abstract class RemoteTrack extends Track {
     if (didStop) {
       await disable();
     }
-    stopMonitor();
     return didStop;
   }
-
-  Timer? _monitorTimer;
-
-  Future<void> monitorReceiver();
-
-  @internal
-  void startMonitor() {
-    _monitorTimer ??=
-        Timer.periodic(const Duration(milliseconds: monitorFrequency), (_) {
-      monitorReceiver();
-    });
-  }
-
-  @internal
-  void stopMonitor() {
-    _monitorTimer?.cancel();
-    _monitorTimer = null;
-  }
 }

lib/src/track/remote/video.dart

@@ -31,10 +31,10 @@ class RemoteVideoTrack extends RemoteTrack with VideoTrack {
   }
 
   @override
-  Future<void> monitorReceiver() async {
+  Future<bool> monitorStats() async {
-    if (receiver == null) {
+    if (receiver == null && events.isDisposed) {
       _currentBitrate = 0;
-      return;
+      return false;
     }
     final stats = await getReceiverStats();
 
@@ -45,6 +45,7 @@ class RemoteVideoTrack extends RemoteTrack with VideoTrack {
     }
 
     prevStats = stats;
+    return true;
   }
 
   Future<VideoReceiverStats?> getReceiverStats() async {

lib/src/track/track.dart

@@ -1,3 +1,5 @@
+import 'dart:async';
+
 import 'package:flutter_webrtc/flutter_webrtc.dart' as rtc;
 import 'package:meta/meta.dart';
 import 'package:uuid/uuid.dart';
@@ -10,6 +12,7 @@ import '../managers/event.dart';
 import '../proto/livekit_models.pb.dart' as lk_models;
 import '../support/disposable.dart';
 import '../types/other.dart';
+import 'stats.dart';
 
 /// Wrapper around a MediaStreamTrack with additional metadata.
 /// Base for [AudioTrack] and [VideoTrack],
@@ -55,6 +58,7 @@ abstract class Track extends DisposableChangeNotifier
 
     onDispose(() async {
       logger.fine('${objectId} onDispose()');
+      await stop();
       // dispose events
       await events.dispose();
     });
@@ -93,6 +97,8 @@ abstract class Track extends DisposableChangeNotifier
 
     logger.fine('$objectId.start()');
 
+    startMonitor();
+
     _active = true;
     return true;
   }
@@ -106,6 +112,8 @@ abstract class Track extends DisposableChangeNotifier
       return false;
     }
 
+    stopMonitor();
+
     logger.fine('$objectId.stop()');
 
     _active = false;
@@ -137,6 +145,26 @@ abstract class Track extends DisposableChangeNotifier
     }
   }
 
+  Timer? _monitorTimer;
+
+  Future<bool> monitorStats();
+
+  @internal
+  void startMonitor() {
+    _monitorTimer ??= Timer.periodic(
+        const Duration(milliseconds: monitorFrequency), (_) async {
+      if (!await monitorStats()) {
+        stopMonitor();
+      }
+    });
+  }
+
+  @internal
+  void stopMonitor() {
+    _monitorTimer?.cancel();
+    _monitorTimer = null;
+  }
+
   @internal
   void updateMuted(
     bool muted, {