Add bloc closure handling and improve device status updates in AcBloc (#298)

<!--
  Thanks for contributing!

Provide a description of your changes below and a general summary in the
title

Please look at the following checklist to ensure that your PR can be
accepted quickly:
-->



## Description

<!--- Describe your changes in detail -->
Add bloc closure handling and improve device status updates in AcBloc
## Type of Change

<!--- Put an `x` in all the boxes that apply: -->

- [ ] ✨ New feature (non-breaking change which adds functionality)
- [x] 🛠️ Bug fix (non-breaking change which fixes an issue)
- [ ] ❌ Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] 🧹 Code refactor
- [ ] ✅ Build configuration change
- [ ] 📝 Documentation
- [ ] 🗑️ Chore

lib/pages/device_managment/ac/bloc/ac_bloc.dart

@@ -45,7 +45,8 @@ class AcBloc extends Bloc<AcsEvent, AcsState> {
   ) async {
     emit(AcsLoadingState());
     try {
-      final status = await DevicesManagementApi().getDeviceStatus(event.deviceId);
+      final status =
+          await DevicesManagementApi().getDeviceStatus(event.deviceId);
       deviceStatus = AcStatusModel.fromJson(event.deviceId, status.status);
       if (deviceStatus.countdown1 != 0) {
         final totalMinutes = deviceStatus.countdown1 * 6;
@@ -68,12 +69,13 @@ class AcBloc extends Bloc<AcsEvent, AcsState> {
     }
   }
 
-  void _listenToChanges(deviceId) {
+  StreamSubscription<DatabaseEvent>? _deviceStatusSubscription;
+
+  void _listenToChanges(String deviceId) {
     try {
       final ref = FirebaseDatabase.instance.ref('device-status/$deviceId');
-      final stream = ref.onValue;
+      _deviceStatusSubscription =
-
+          ref.onValue.listen((DatabaseEvent event) async {
-      stream.listen((DatabaseEvent event) async {
         if (event.snapshot.value == null) return;
 
         Map<dynamic, dynamic> usersMap =
@@ -82,10 +84,14 @@ class AcBloc extends Bloc<AcsEvent, AcsState> {
         List<Status> statusList = [];
 
         usersMap['status'].forEach((element) {
-          statusList.add(Status(code: element['code'], value: element['value']));
+          statusList
+              .add(Status(code: element['code'], value: element['value']));
         });
 
-        deviceStatus = AcStatusModel.fromJson(usersMap['productUuid'], statusList);
+        deviceStatus =
+            AcStatusModel.fromJson(usersMap['productUuid'], statusList);
+        print('Device status updated: ${deviceStatus.acSwitch}');
+
         if (!isClosed) {
           add(AcStatusUpdated(deviceStatus));
         }
@@ -106,15 +112,14 @@ class AcBloc extends Bloc<AcsEvent, AcsState> {
     Emitter<AcsState> emit,
   ) async {
     emit(AcsLoadingState());
-    _updateDeviceFunctionFromCode(event.code, event.value);
-    emit(ACStatusLoaded(status: deviceStatus));
 
     try {
       final success = await controlDeviceService.controlDevice(
         deviceUuid: event.deviceId,
         status: Status(code: event.code, value: event.value),
       );
-
+      _updateDeviceFunctionFromCode(event.code, event.value);
+      emit(ACStatusLoaded(status: deviceStatus));
       if (!success) {
         emit(const AcsFailedState(error: 'Failed to control device'));
       }
@@ -129,8 +134,10 @@ class AcBloc extends Bloc<AcsEvent, AcsState> {
   ) async {
     emit(AcsLoadingState());
     try {
-      final status = await DevicesManagementApi().getBatchStatus(event.devicesIds);
+      final status =
-      deviceStatus = AcStatusModel.fromJson(event.devicesIds.first, status.status);
+          await DevicesManagementApi().getBatchStatus(event.devicesIds);
+      deviceStatus =
+          AcStatusModel.fromJson(event.devicesIds.first, status.status);
       emit(ACStatusLoaded(status: deviceStatus));
     } catch (e) {
       emit(AcsFailedState(error: e.toString()));
@@ -293,13 +300,17 @@ class AcBloc extends Bloc<AcsEvent, AcsState> {
         totalSeconds--;
         scheduledHours = totalSeconds ~/ 3600;
         scheduledMinutes = (totalSeconds % 3600) ~/ 60;
-        add(UpdateTimerEvent());
+        if (!isClosed) {
+          add(UpdateTimerEvent());
+        }
       } else {
         _countdownTimer?.cancel();
         timerActive = false;
         scheduledHours = 0;
         scheduledMinutes = 0;
-        add(TimerCompletedEvent());
+        if (!isClosed) {
+          add(TimerCompletedEvent());
+        }
       }
     });
   }
@@ -326,7 +337,9 @@ class AcBloc extends Bloc<AcsEvent, AcsState> {
       _startCountdownTimer(
         emit,
       );
-      add(UpdateTimerEvent());
+      if (!isClosed) {
+        add(UpdateTimerEvent());
+      }
     }
   }
 
@@ -370,6 +383,8 @@ class AcBloc extends Bloc<AcsEvent, AcsState> {
   @override
   Future<void> close() {
     add(OnClose());
+    _countdownTimer?.cancel();
+    _deviceStatusSubscription?.cancel();
     return super.close();
   }
 }