fix: clear home_widget on logout, init in login

lib/core/configuration.dart

@@ -1,3 +1,4 @@
+import "dart:async";
 import 'dart:convert';
 import "dart:io";
 import 'dart:typed_data';
@@ -18,6 +19,7 @@ import 'package:photos/db/trash_db.dart';
 import 'package:photos/db/upload_locks_db.dart';
 import 'package:photos/events/signed_in_event.dart';
 import 'package:photos/events/user_logged_out_event.dart';
+import "package:photos/main.dart";
 import 'package:photos/models/key_attributes.dart';
 import 'package:photos/models/key_gen_result.dart';
 import 'package:photos/models/private_key_attributes.dart';
@@ -174,6 +176,7 @@ class Configuration {
       MemoriesService.instance.clearCache();
       BillingService.instance.clearCache();
       SearchService.instance.clearCache();
+      unawaited(clearHomeWidget());
       Bus.instance.fire(UserLoggedOutEvent());
     } else {
       await _preferences.setBool("auto_logout", true);

lib/main.dart

@@ -72,23 +72,38 @@ const kBackgroundLockLatency = Duration(seconds: 3);
 void initSlideshowWidget() {
   Workmanager().executeTask(
     (taskName, inputData) async {
+      try {
         await _init(true, via: 'runViaSlideshowWidget');
+        await initHomeWidget();
+        return true;
+      } catch (e, s) {
+        _logger.severe("Error in initSlideshowWidget", e, s);
+        return false;
+      }
+    },
+  );
+}
+
+Future initHomeOnLogin() async {
+  _logger.info("Initializing SlideshowWidget on login");
+  initHomeWidget().catchError((e, s) {
+    _logger.severe("SlideshowWidget: Error in initHomeOnLogin", e, s);
+  }).ignore();
+}
+
+Future<void> initHomeWidget() async {
+  final user = Configuration.instance.getUserID();
+
+  if (user == null) {
+    await clearHomeWidget();
+    throw Exception("User not found");
+  }
 
   final collectionID =
       await FavoritesService.instance.getFavoriteCollectionID();
   if (collectionID == null) {
-        await hw.HomeWidget.saveWidgetData(
+    await clearHomeWidget();
-          "slideshow",
+    throw Exception("Collection not found");
-          null,
-        );
-
-        await hw.HomeWidget.updateWidget(
-          name: 'SlideshowWidgetProvider',
-          androidName: 'SlideshowWidgetProvider',
-          qualifiedAndroidName: 'io.ente.photos.SlideshowWidgetProvider',
-          iOSName: 'SlideshowWidget',
-        );
-        return false;
   }
 
   try {
@@ -109,7 +124,7 @@ void initSlideshowWidget() {
     final randomNumber = Random().nextInt(files.length);
     final randomFile = files.elementAt(randomNumber);
     final fullImage = await getFileFromServer(randomFile);
-        if (fullImage == null) return false;
+    if (fullImage == null) throw Exception("File not found");
 
     Image img = Image.file(fullImage);
     var imgProvider = img.image;
@@ -158,12 +173,29 @@ void initSlideshowWidget() {
     _logger.info(
       ">>> SlideshowWidget rendered with size ${width}x$height",
     );
-        return true;
   } catch (_) {
-        return false;
+    throw Exception("Error rendering widget");
   }
-    },
+}
+
+Future<void> clearHomeWidget() async {
+  final previousGeneratedId =
+      await hw.HomeWidget.getWidgetData<int>("home_widget_last_img");
+  if (previousGeneratedId == null) return;
+
+  _logger.info("Clearing SlideshowWidget");
+  await hw.HomeWidget.saveWidgetData(
+    "slideshow",
+    null,
   );
+
+  await hw.HomeWidget.updateWidget(
+    name: 'SlideshowWidgetProvider',
+    androidName: 'SlideshowWidgetProvider',
+    qualifiedAndroidName: 'io.ente.photos.SlideshowWidgetProvider',
+    iOSName: 'SlideshowWidget',
+  );
+  _logger.info(">>> SlideshowWidget cleared");
 }
 
 Future<void> initWorkmanager() async {

lib/ui/tabs/home_widget.dart

@@ -24,6 +24,7 @@ import 'package:photos/events/tab_changed_event.dart';
 import 'package:photos/events/trigger_logout_event.dart';
 import 'package:photos/events/user_logged_out_event.dart';
 import "package:photos/generated/l10n.dart";
+import "package:photos/main.dart";
 import 'package:photos/models/collection/collection_items.dart';
 import 'package:photos/models/selected_files.dart';
 import 'package:photos/services/app_lifecycle_service.dart';
@@ -107,6 +108,7 @@ class _HomeWidgetState extends State<HomeWidget> {
   @override
   void initState() {
     _logger.info("Building initstate");
+    unawaited(initHomeOnLogin());
     _tabChangedEventSubscription =
         Bus.instance.on<TabChangedEvent>().listen((event) {
       _selectedTabIndex = event.selectedIndex;