fix: reconnect websocket on error and disconnection

Author: Ephraim Nartey

lib/data/chatwoot_repository.dart

@@ -54,6 +54,8 @@ class ChatwootRepositoryImpl extends ChatwootRepository {
   bool _isListeningForEvents = false;
   Timer? _publishPresenceTimer;
   Timer? _presenceResetTimer;
+  Timer? _checkPingTimer;
+  DateTime? _lastPingTime;
 
   ChatwootRepositoryImpl(
       {required ChatwootClientService clientService,
@@ -153,11 +155,16 @@ class ChatwootRepositoryImpl extends ChatwootRepository {
     clientService.startWebSocketConnection(
         localStorage.contactDao.getContact()!.pubsubToken ?? "");
 
-    final newSubscription = clientService.connection!.stream.listen((event) async{
+    final newSubscription = clientService.connection!.stream.listen(
+            (event) async{
       ChatwootEvent chatwootEvent = ChatwootEvent.fromJson(jsonDecode(event));
       if (chatwootEvent.type == ChatwootEventType.welcome) {
         callbacks.onWelcome?.call();
       } else if (chatwootEvent.type == ChatwootEventType.ping) {
+        if(_lastPingTime == null){
+          _startPingCheck();
+        }
+        _lastPingTime = DateTime.now();
         callbacks.onPing?.call();
       } else if (chatwootEvent.type == ChatwootEventType.confirm_subscription) {
         if (!_isListeningForEvents) {
@@ -219,6 +226,11 @@ class ChatwootRepositoryImpl extends ChatwootRepository {
       } else {
         print("chatwoot unknown event: $event");
       }
+    },
+    onError: (e){
+      //auto reconnect on error
+      print("chatwoot websocket: $e");
+      listenForEvents();
     });
     _subscriptions.add(newSubscription);
   }
@@ -236,6 +248,7 @@ class ChatwootRepositoryImpl extends ChatwootRepository {
     callbacks = ChatwootCallbacks();
     _presenceResetTimer?.cancel();
     _publishPresenceTimer?.cancel();
+    _checkPingTimer?.cancel();
     _subscriptions.forEach((subs) {
       subs.cancel();
     });
@@ -248,6 +261,23 @@ class ChatwootRepositoryImpl extends ChatwootRepository {
         localStorage.contactDao.getContact()!.pubsubToken ?? "", action);
   }
 
+  /// Start a timer to check for missed pings
+  void _startPingCheck() {
+    _checkPingTimer = Timer.periodic(const Duration(seconds: 1), (timer) {
+      final now = DateTime.now();
+      if (_lastPingTime != null &&
+          now.difference(_lastPingTime!).inSeconds > 30) {
+        print("No ping received in 30 seconds. Reconnecting...");
+        _lastPingTime = null;
+        _checkPingTimer?.cancel();
+        _checkPingTimer = null;
+        listenForEvents();
+        //get any lost messages
+        getMessages();
+      }
+    });
+  }
+
   ///Publishes presence update to websocket channel at a 30 second interval
   void _publishPresenceUpdates() {
     sendAction(ChatwootActionType.update_presence);