Add Gitea update notifications

lib/backend/services/update_service.dart

@@ -0,0 +1,125 @@
+import 'package:dio/dio.dart';
+
+import '../../app/app_version.dart';
+import '../../core/errors/failure.dart';
+import '../../core/utils/result.dart';
+import '../models/app_update_info.dart';
+import 'settings_service.dart';
+
+class UpdateService {
+  UpdateService(this._dio, this._settingsService);
+
+  static const latestReleaseUrl =
+      'https://gitea.rardogsynapse.online/api/v1/repos/RarDog/RuleGelApp/releases/latest';
+
+  final Dio _dio;
+  final SettingsService _settingsService;
+
+  Future<Result<AppUpdateInfo?>> checkForUpdates({bool force = false}) async {
+    final settingsResult = await _settingsService.getSettings();
+    final settings = settingsResult is Success<AppSettings>
+        ? settingsResult.data
+        : AppSettings.defaults;
+
+    if (!force && !_shouldCheck(settings)) return const Success(null);
+
+    try {
+      final response = await _dio.get<dynamic>(latestReleaseUrl);
+      final data = Map<String, dynamic>.from(response.data as Map);
+      final info = _releaseFromJson(data);
+      final nextSettings = settings.copyWith(
+        lastUpdateCheckAt: DateTime.now().toIso8601String(),
+      );
+      await _settingsService.updateSettings(nextSettings);
+
+      final skipped = settings.skippedUpdateVersion == info.version ||
+          settings.skippedUpdateVersion == info.tagName;
+      if (!force && skipped) return const Success(null);
+      if (!_isNewerVersion(info.version, appDisplayVersion)) {
+        return const Success(null);
+      }
+      return Success(info);
+    } catch (error) {
+      return Error(
+        Failure(
+          code: 'update_check_failed',
+          message: 'Could not check for updates',
+          details: error,
+        ),
+      );
+    }
+  }
+
+  Future<Result<void>> remindLater() async {
+    final result = await _settingsService.getSettings();
+    if (result is Error<AppSettings>) return Error(result.failure);
+    final settings = (result as Success<AppSettings>).data;
+    return _settingsService.updateSettings(
+      settings.copyWith(lastUpdateCheckAt: DateTime.now().toIso8601String()),
+    );
+  }
+
+  Future<Result<void>> skipVersion(AppUpdateInfo info) async {
+    final result = await _settingsService.getSettings();
+    if (result is Error<AppSettings>) return Error(result.failure);
+    final settings = (result as Success<AppSettings>).data;
+    return _settingsService.updateSettings(
+      settings.copyWith(skippedUpdateVersion: info.version),
+    );
+  }
+
+  bool _shouldCheck(AppSettings settings) {
+    final last = DateTime.tryParse(settings.lastUpdateCheckAt ?? '');
+    if (last == null) return true;
+    return DateTime.now().difference(last) >= const Duration(hours: 24);
+  }
+
+  AppUpdateInfo _releaseFromJson(Map<String, dynamic> json) {
+    final tag = (json['tag_name'] ?? '').toString();
+    final assets = (json['assets'] as List?) ?? const [];
+    String? apkUrl;
+    String? installerUrl;
+    for (final item in assets.whereType<Map>()) {
+      final name = (item['name'] ?? '').toString().toLowerCase();
+      final url = (item['browser_download_url'] ?? '').toString();
+      if (url.isEmpty) continue;
+      if (name.endsWith('.apk')) apkUrl = url;
+      if (name.endsWith('.exe')) installerUrl = url;
+    }
+    return AppUpdateInfo(
+      version: _versionFromTag(tag),
+      tagName: tag,
+      name: (json['name'] ?? tag).toString(),
+      body: (json['body'] ?? '').toString(),
+      htmlUrl: (json['html_url'] ?? '').toString(),
+      publishedAt: DateTime.tryParse((json['published_at'] ?? '').toString()),
+      apkUrl: apkUrl,
+      windowsInstallerUrl: installerUrl,
+    );
+  }
+
+  static String _versionFromTag(String tag) {
+    final match = RegExp(r'v?(\d+\.\d+\.\d+)').firstMatch(tag);
+    return match?.group(1) ?? tag.replaceFirst(RegExp(r'^v'), '');
+  }
+
+  static bool _isNewerVersion(String latest, String current) {
+    final left = _parts(latest);
+    final right = _parts(current);
+    for (var i = 0; i < 3; i++) {
+      if (left[i] > right[i]) return true;
+      if (left[i] < right[i]) return false;
+    }
+    return false;
+  }
+
+  static List<int> _parts(String value) {
+    final match = RegExp(r'(\d+)\.(\d+)\.(\d+)').firstMatch(value);
+    if (match == null) return const [0, 0, 0];
+    return [
+      int.tryParse(match.group(1) ?? '') ?? 0,
+      int.tryParse(match.group(2) ?? '') ?? 0,
+      int.tryParse(match.group(3) ?? '') ?? 0,
+    ];
+  }
+}