Merge pull request #46 from Metatavu/feature-45-improve-realtime-comm…

…unication

Feature 45 improve realtime communication

lib/event_bus/event_bus.dart

@@ -1,12 +1,38 @@
 import "package:event_bus/event_bus.dart";
+import "package:noheva_visitor_ui/widgets/noheva_widgets.dart";
+import "package:noheva_visitor_ui/mqtt/listeners/pages_listener.dart";
+import "package:noheva_visitor_ui/screens/page_screen.dart";
 
 /// This module contains the event bus instance and, at the moment, all the events that are used in the app.
 
 final EventBus eventBus = EventBus();
 
+/// Event that is triggered when the user clicks on a play button.
+/// [NohevaVideo] then starts playing the video.
 class PlayVideoEvent {}
 
+/// Event that is triggered when the [NohevaVideo] wants to toggle the play button.
 class HidePlayButtonEvent {
   final bool hide;
   HidePlayButtonEvent(this.hide);
 }
+
+/// Event that is triggered when [PagesListener] needs to know what exhibition page is currenty being disabled.
+class RequestAchiveExhibitionPageIdEvent {}
+
+/// Event that is sent by [PageScreen] as a response to [RequestAchiveExhibitionPageIdEvent].
+class ActiveExhibitionPageIdEvent {
+  final String? pageId;
+  ActiveExhibitionPageIdEvent(this.pageId);
+}
+
+/// Event that is triggered when the software wants to load a new exhibition page.
+///
+/// e.g. when the device boots and it it attached to an exhibition and has content to be dispayed
+class LoadExhibitionPageByIdEvent {
+  final String? pageId;
+  LoadExhibitionPageByIdEvent(this.pageId);
+}
+
+/// Event that is triggered when the software needs to navigate to the management screen.
+class OpenManagementScreenEvent {}

lib/main.dart

@@ -5,6 +5,7 @@ import "package:flutter/material.dart";
 import "package:flutter/services.dart";
 import "package:flutter_dotenv/flutter_dotenv.dart";
 import "package:noheva_api/noheva_api.dart";
+import "package:noheva_visitor_ui/event_bus/event_bus.dart";
 import "package:noheva_visitor_ui/mqtt/mqtt_client.dart";
 import "package:noheva_visitor_ui/screens/startup_screen.dart";
 import "package:noheva_visitor_ui/theme/font_helper.dart";
@@ -23,14 +24,10 @@ late final String environment;
 final apiFactory = ApiFactory();
 late bool isDeviceApproved;
 String? deviceId;
-final StreamController<String?> pageStreamController =
-    StreamController.broadcast(sync: true);
-final StreamController<bool?> managementStreamController =
-    StreamController.broadcast(sync: true);
 final managementButtonTickCounter = TimedTickCounter(
   ticksRequired: 10,
   timeout: const Duration(seconds: 5),
-  onTicksReached: () => managementStreamController.sink.add(true),
+  onTicksReached: () => eventBus.fire(OpenManagementScreenEvent()),
 );
 
 Future<void> _setAndroidImmersiveMode() async {
@@ -160,7 +157,7 @@ void _addManagementButtonOverlay(BuildContext context) {
   return Overlay.of(context).insert(
     OverlayEntry(
       builder: (context) => Positioned(
-        left: MediaQuery.of(context).size.width / 2 - 100,
+        left: MediaQuery.of(context).size.width / 3,
         top: 0,
         width: 200,
         height: 100,

lib/mqtt/listeners/attach_listener.dart

@@ -3,6 +3,7 @@ import "package:noheva_visitor_ui/database/dao/device_exhibition_detail_dao.dart
 import "package:noheva_visitor_ui/database/dao/layout_dao.dart";
 import "package:noheva_visitor_ui/database/dao/page_dao.dart";
 import "package:noheva_visitor_ui/database/database.dart";
+import "package:noheva_visitor_ui/event_bus/event_bus.dart";
 import "package:noheva_visitor_ui/main.dart";
 import "package:noheva_visitor_ui/mqtt/listeners/abstract_listener.dart";
 import "package:noheva_visitor_ui/mqtt/mqtt_client.dart";
@@ -58,7 +59,7 @@ class AttachListener {
     SimpleLogger().info("Successfully loaded pages!");
     final firstPage =
         await pageDao.findPageByOrderNumber(attachedMessage.exhibitionId!, 0);
-    pageStreamController.sink.add(firstPage?.id);
+    eventBus.fire(LoadExhibitionPageByIdEvent(firstPage?.id));
   }
 
   /// Callback function for handling detach messages
@@ -86,6 +87,6 @@ class AttachListener {
     SimpleLogger().info("Deleted layouts!");
     await deviceExhitionDetailDao.deleteDeviceExhibitionDetails();
     SimpleLogger().info("Deleted exhibitions!");
-    pageStreamController.sink.add(null);
+    eventBus.fire(LoadExhibitionPageByIdEvent(null));
   }
 }

lib/mqtt/listeners/pages_listener.dart

@@ -1,5 +1,12 @@
+import "dart:async";
+
 import "package:noheva_api/noheva_api.dart";
+import "package:noheva_visitor_ui/database/dao/page_dao.dart";
+import "package:noheva_visitor_ui/event_bus/event_bus.dart";
+import "package:noheva_visitor_ui/main.dart";
 import "package:noheva_visitor_ui/mqtt/listeners/abstract_listener.dart";
+import "package:noheva_visitor_ui/utils/layout_controller.dart";
+import "package:noheva_visitor_ui/utils/page_controller.dart";
 import "package:simple_logger/simple_logger.dart";
 
 /// MQTT listener for Exhibition Pages
@@ -8,32 +15,106 @@ class PagesListener extends AbstractListener {
   String baseTopic = "${AbstractListener.BASE_TOPIC}/pages";
 
   @override
-  void handleCreate(String message) {
+  void handleCreate(String message) async {
     SimpleLogger().info("Handling page create message...");
     final createMessage =
         AbstractListener.decodeMessage<MqttExhibitionPageCreate>(
             message, MqttExhibitionPageCreate);
     SimpleLogger().info(createMessage);
-    // TODO: Implement logic for handling page create messages
+    final createdPageId = createMessage.id;
+    final exhibitionId = createMessage.exhibitionId;
+    if (createdPageId == null) {
+      SimpleLogger()
+          .info("Page ID is null, cannot handle page create message!");
+      return;
+    }
+    if (exhibitionId == null) {
+      SimpleLogger()
+          .info("Exhibition ID is null, cannot handle page create message!");
+      return;
+    }
+    final existingPage = await pageDao.findPage(createdPageId);
+    if (existingPage != null) {
+      SimpleLogger().info("Page already exists, ignoring...");
+      return;
+    }
+
+    await _loadData(exhibitionId);
   }
 
   @override
-  void handleDelete(String message) {
+  void handleDelete(String message) async {
     SimpleLogger().info("Handling page delete message...");
     final deleteMessage =
         AbstractListener.decodeMessage<MqttExhibitionPageDelete>(
             message, MqttExhibitionPageDelete);
     SimpleLogger().info(deleteMessage);
-    // TODO: Implement logic for handling page delete messages
+    final deletedPageId = deleteMessage.id;
+    if (deletedPageId == null) {
+      SimpleLogger()
+          .info("Page ID is null, cannot handle page delete message!");
+      return;
+    }
+    final existingPage = await pageDao.findPage(deletedPageId);
+    if (existingPage == null) {
+      SimpleLogger().info("Page does not exist, ignoring...");
+      return;
+    }
+    await pageDao.deletePage(deletedPageId);
+    SimpleLogger().info("Deleted page: $deletedPageId");
   }
 
   @override
-  void handleUpdate(String message) {
+  void handleUpdate(String message) async {
     SimpleLogger().info("Handling page update message...");
     final updateMessage =
         AbstractListener.decodeMessage<MqttExhibitionPageUpdate>(
             message, MqttExhibitionPageUpdate);
     SimpleLogger().info(updateMessage);
-    // TODO: Implement logic for handling page update messages
+    final updatedPageId = updateMessage.id;
+    final exhibitionId = updateMessage.exhibitionId;
+    if (updatedPageId == null) {
+      SimpleLogger()
+          .info("Page ID is null, cannot handle page update message!");
+      return;
+    }
+    if (exhibitionId == null) {
+      SimpleLogger()
+          .info("Exhibition ID is null, cannot handle page update message!");
+      return;
+    }
+    final existingPage = await pageDao.findPage(updatedPageId);
+    if (existingPage == null) {
+      SimpleLogger().info("Page does not exist, ignoring...");
+      return;
+    }
+
+    await _loadData(exhibitionId);
+    eventBus.fire(RequestAchiveExhibitionPageIdEvent());
+    final activePageId = await eventBus
+        .on<ActiveExhibitionPageIdEvent>()
+        .first
+        .then((value) => value.pageId);
+    if (activePageId == updatedPageId) {
+      SimpleLogger().info("Page is active, updating screen...");
+      eventBus.fire(LoadExhibitionPageByIdEvent(activePageId));
+    } else {
+      SimpleLogger().info("Page is not active, not updating!");
+    }
+  }
+
+  /// Loads layouts and pages for the this device
+  Future<void> _loadData(String exhibitionId) async {
+    SimpleLogger().info("Loading layouts...");
+    await LayoutController.loadLayouts(deviceId!);
+    SimpleLogger().info("Successfully loaded layouts!");
+    SimpleLogger().info("Loading pages...");
+    final deviceDataApi = await apiFactory.getDeviceDataApi();
+    final pages = (await deviceDataApi.listDeviceDataPages(
+      deviceId: deviceId!,
+    ))
+        .data!
+        .toList();
+    await PageController.comparePages(exhibitionId, pages);
   }
 }

lib/screens/default_screen.dart

@@ -4,6 +4,7 @@ import "package:flutter_gen/gen_l10n/app_localizations.dart";
 import "package:noheva_visitor_ui/database/dao/device_exhibition_detail_dao.dart";
 import "package:noheva_visitor_ui/database/dao/key_dao.dart";
 import "package:noheva_visitor_ui/database/dao/page_dao.dart";
+import "package:noheva_visitor_ui/event_bus/event_bus.dart";
 import "package:noheva_visitor_ui/main.dart";
 import "package:noheva_visitor_ui/screens/page_screen.dart";
 import "package:noheva_visitor_ui/utils/layout_controller.dart";
@@ -21,7 +22,8 @@ class DefaultScreen extends StatefulWidget {
 /// Default Screen State
 class _DefaultScreenState extends State<DefaultScreen> {
   bool _isDeviceApproved = false;
-  late StreamSubscription<String?> _pageStreamSubscription;
+  late StreamSubscription<LoadExhibitionPageByIdEvent>
+      _loadExhibitionPageByIdEventSubscription;
   Timer? _deviceApprovalTimer;
 
   /// Navigates to [PageScreen] with [pageId]
@@ -37,9 +39,10 @@ class _DefaultScreenState extends State<DefaultScreen> {
   /// Handles stream events
   ///
   /// If event is not null, navigates to [PageScreen] with [event] as [pageId]
-  void _handleStreamEvent(dynamic event) {
-    if (event != null) {
-      _navigateToPageScreen(event);
+  void _handleStreamEvent(LoadExhibitionPageByIdEvent event) {
+    final eventPageId = event.pageId;
+    if (eventPageId != null) {
+      _navigateToPageScreen(eventPageId);
     }
   }
 
@@ -107,14 +110,14 @@ class _DefaultScreenState extends State<DefaultScreen> {
   @override
   void initState() {
     super.initState();
-    _pageStreamSubscription =
-        pageStreamController.stream.listen(_handleStreamEvent);
+    _loadExhibitionPageByIdEventSubscription =
+        eventBus.on<LoadExhibitionPageByIdEvent>().listen(_handleStreamEvent);
     _checkDeviceApproval();
   }
 
   @override
   void dispose() {
-    _pageStreamSubscription.cancel();
+    _loadExhibitionPageByIdEventSubscription.cancel();
     _deviceApprovalTimer?.cancel();
     super.dispose();
   }

lib/screens/noheva_screen.dart

@@ -5,7 +5,7 @@ import "package:flutter/services.dart";
 import "package:noheva_api/noheva_api.dart";
 import 'package:noheva_visitor_ui/actions/key_event_listener.dart';
 import "package:noheva_visitor_ui/actions/page_action_provider_factory.dart";
-import "package:noheva_visitor_ui/main.dart";
+import "package:noheva_visitor_ui/event_bus/event_bus.dart";
 import "package:noheva_visitor_ui/screens/management_screen.dart";
 
 /// Abstract Noheva Screen
@@ -20,30 +20,29 @@ abstract class NohevaScreen extends StatefulWidget {
 /// All screens states should extend this class.
 /// Provides a stream subscription for navigating to management screen when required.
 abstract class NohevaScreenState<T extends NohevaScreen> extends State<T> {
-  late StreamSubscription<bool?> _managementButtonStreamSubscription;
+  late StreamSubscription<OpenManagementScreenEvent>
+      _managementButtonEventSubscription;
   final List<KeyEventListener> _keyDownListeners = [];
   final List<KeyEventListener> _keyUpListeners = [];
 
   @override
   void initState() {
     super.initState();
-    _managementButtonStreamSubscription =
-        managementStreamController.stream.listen((event) {
-      if (event != null) {
-        Navigator.push(
-          context,
-          MaterialPageRoute<NohevaScreen>(
-            builder: (_) => const ManagementScreen(),
-          ),
-        );
-      }
+    _managementButtonEventSubscription =
+        eventBus.on<OpenManagementScreenEvent>().listen((_) {
+      Navigator.push(
+        context,
+        MaterialPageRoute<NohevaScreen>(
+          builder: (_) => const ManagementScreen(),
+        ),
+      );
     });
     ServicesBinding.instance.keyboard.addHandler(_keyEventHandler);
   }
 
   @override
   void dispose() {
-    _managementButtonStreamSubscription.cancel();
+    _managementButtonEventSubscription.cancel();
     ServicesBinding.instance.keyboard.removeHandler(_keyEventHandler);
     super.dispose();
   }

lib/screens/page_screen.dart

@@ -5,7 +5,7 @@ import "package:flutter_widget_from_html_core/flutter_widget_from_html_core.dart
 import "package:noheva_api/noheva_api.dart";
 import "package:noheva_visitor_ui/database/dao/layout_dao.dart";
 import "package:noheva_visitor_ui/database/dao/page_dao.dart";
-import "package:noheva_visitor_ui/main.dart";
+import "package:noheva_visitor_ui/event_bus/event_bus.dart";
 import "package:noheva_visitor_ui/screens/default_screen.dart";
 import "package:noheva_visitor_ui/screens/noheva_screen.dart";
 import "package:noheva_visitor_ui/utils/custom_widget_factory.dart";
@@ -31,7 +31,10 @@ class PageScreenState extends NohevaScreenState<PageScreen> {
   final List<ExhibitionPageEventTrigger> _eventTriggers = [];
   final List<ExhibitionPageTransition> _enterTransitions = [];
   final List<ExhibitionPageTransition> _exitTransitions = [];
-  late StreamSubscription<String?> _streamSubscription;
+  late StreamSubscription<LoadExhibitionPageByIdEvent>
+      _loadExhibitionPageByIdEventSubscription;
+  late StreamSubscription<RequestAchiveExhibitionPageIdEvent>
+      _activeExhibitionPageIdEventStreamSubscription;
 
   /// Loads page and its content by [pageId]
   Future<void> _loadPage(String pageId) async {
@@ -64,9 +67,11 @@ class PageScreenState extends NohevaScreenState<PageScreen> {
   void initState() {
     super.initState();
     _loadPage(widget.pageId);
-    _streamSubscription = pageStreamController.stream.listen((event) {
-      if (event != null) {
-        _loadPage(event);
+    _loadExhibitionPageByIdEventSubscription =
+        eventBus.on<LoadExhibitionPageByIdEvent>().listen((event) {
+      final eventPageId = event.pageId;
+      if (eventPageId != null) {
+        _loadPage(eventPageId);
       } else {
         Navigator.pushReplacement(
           context,
@@ -76,11 +81,18 @@ class PageScreenState extends NohevaScreenState<PageScreen> {
         );
       }
     });
+    _activeExhibitionPageIdEventStreamSubscription =
+        eventBus.on<RequestAchiveExhibitionPageIdEvent>().listen(
+              (_) => eventBus.fire(
+                ActiveExhibitionPageIdEvent(widget.pageId),
+              ),
+            );
   }
 
   @override
   void dispose() {
-    _streamSubscription.cancel();
+    _loadExhibitionPageByIdEventSubscription.cancel();
+    _activeExhibitionPageIdEventStreamSubscription.cancel();
     super.dispose();
   }