show release notes dialog after update

lib/data/shared_prefs_service.dart

@@ -32,6 +32,8 @@ class UserPreferencesService {
   static const primaryColorKey = "primaryColor";
   static const dynamicColorKey = "dynamicColor";
 
+  static const seenChangelogVersionKey = "seenChangelogVersion";
+
   final SharedPreferences _sharedPreferences;
 
   UserPreferencesService(this._sharedPreferences) {
@@ -157,4 +159,7 @@ class UserPreferencesService {
 
   bool get dynamicColor => _sharedPreferences.getBool(dynamicColorKey) ?? false;
   set dynamicColor(bool value) => _sharedPreferences.setBool(dynamicColorKey, value);
+
+  String get seenChangelogVersion => _sharedPreferences.getString(seenChangelogVersionKey) ?? '';
+  set seenChangelogVersion(String value) => _sharedPreferences.setString(seenChangelogVersionKey, value);
 }

lib/screens/shared/release_notes_dialog/bloc_release_notes.dart

@@ -0,0 +1,27 @@
+import 'dart:async';
+
+import 'package:flutter_bloc/flutter_bloc.dart';
+import 'package:lightmeter/data/shared_prefs_service.dart';
+import 'package:lightmeter/screens/shared/release_notes_dialog/state_release_notes.dart';
+import 'package:package_info_plus/package_info_plus.dart';
+
+class ReleaseNotesBloc extends Cubit<ReleaseNotesState> {
+  final UserPreferencesService _userPreferencesService;
+
+  ReleaseNotesBloc(this._userPreferencesService) : super(const HiddenReleaseNotesDialogState()) {
+    _showDialogIfNeeded();
+  }
+
+  Future<void> _showDialogIfNeeded() async {
+    PackageInfo.fromPlatform().then((value) {
+      emit(ShowReleaseNotesDialogState(value.version));
+      if (value.version != _userPreferencesService.seenChangelogVersion) {
+        emit(ShowReleaseNotesDialogState(value.version));
+      }
+    });
+  }
+
+  void setChangelogVersion() {
+    _userPreferencesService.seenChangelogVersion = (state as ShowReleaseNotesDialogState).version;
+  }
+}

lib/screens/shared/release_notes_dialog/flow_dialog_release_notes.dart

@@ -0,0 +1,30 @@
+import 'package:flutter/material.dart';
+import 'package:flutter_bloc/flutter_bloc.dart';
+import 'package:lightmeter/providers/services_provider.dart';
+import 'package:lightmeter/screens/shared/release_notes_dialog/bloc_release_notes.dart';
+import 'package:lightmeter/screens/shared/release_notes_dialog/state_release_notes.dart';
+import 'package:lightmeter/screens/shared/release_notes_dialog/widget_dialog_release_notes.dart';
+
+class ReleaseNotesFlow extends StatelessWidget {
+  final Widget child;
+
+  const ReleaseNotesFlow({required this.child, super.key});
+
+  @override
+  Widget build(BuildContext context) {
+    return BlocProvider(
+      create: (context) => ReleaseNotesBloc(ServicesProvider.of(context).userPreferencesService),
+      child: BlocListener<ReleaseNotesBloc, ReleaseNotesState>(
+        listener: (context, state) {
+          if (state is ShowReleaseNotesDialogState) {
+            showDialog(
+              context: context,
+              builder: (_) => ReleaseNotesDialog(version: state.version),
+            ).then((_) => context.read<ReleaseNotesBloc>().setChangelogVersion());
+          }
+        },
+        child: child,
+      ),
+    );
+  }
+}

lib/screens/shared/release_notes_dialog/state_release_notes.dart

@@ -0,0 +1,16 @@
+import 'package:flutter/material.dart';
+
+@immutable
+sealed class ReleaseNotesState {
+  const ReleaseNotesState();
+}
+
+class HiddenReleaseNotesDialogState extends ReleaseNotesState {
+  const HiddenReleaseNotesDialogState();
+}
+
+class ShowReleaseNotesDialogState extends ReleaseNotesState {
+  final String version;
+
+  const ShowReleaseNotesDialogState(this.version);
+}

lib/screens/shared/release_notes_dialog/widget_dialog_release_notes.dart

@@ -1,12 +1,14 @@
 import 'package:flutter/material.dart';
 import 'package:flutter/services.dart' show rootBundle;
+import 'package:lightmeter/data/models/supported_locale.dart';
 import 'package:lightmeter/generated/l10n.dart';
 import 'package:lightmeter/providers/user_preferences_provider.dart';
 import 'package:lightmeter/res/dimens.dart';
-import 'package:package_info_plus/package_info_plus.dart';
 
 class ReleaseNotesDialog extends StatelessWidget {
-  const ReleaseNotesDialog({super.key});
+  final String version;
+
+  const ReleaseNotesDialog({required this.version, super.key});
 
   @override
   Widget build(BuildContext context) {
@@ -16,13 +18,10 @@ class ReleaseNotesDialog extends StatelessWidget {
         child: Column(
           crossAxisAlignment: CrossAxisAlignment.start,
           children: [
-            FutureBuilder<PackageInfo>(
-              future: PackageInfo.fromPlatform(),
-              builder: (context, snapshot) => Text(
-                S.of(context).changesInVersion(snapshot.data?.version ?? ''),
+            Text(
+              S.of(context).changesInVersion(version),
               style: Theme.of(context).textTheme.titleSmall,
             ),
-            ),
             const SizedBox(height: Dimens.grid8),
             FutureBuilder<String>(
               future: loadReleaseNotes(context),
@@ -41,12 +40,19 @@ class ReleaseNotesDialog extends StatelessWidget {
   }
 
   Future<String> loadReleaseNotes(BuildContext context) async {
-    String path(String locale) => 'assets/release_notes/release_notes_$locale.md';
+    late final String localeName;
+
+    switch (UserPreferencesProvider.localeOf(context)) {
+      case SupportedLocale.ru:
+        localeName = SupportedLocale.ru.name;
+      default:
+        localeName = SupportedLocale.en.name;
+    }
 
     try {
-      return rootBundle.loadString(path(UserPreferencesProvider.localeOf(context).name));
+      return rootBundle.loadString('assets/release_notes/release_notes_${localeName}_$version.md');
     } catch (e) {
-      return rootBundle.loadString(path('en'));
+      return '';
     }
   }
 }