二次开发源码提交

2026-05-15 08:52:48 +08:00
parent 4131f7321a
commit eb35a1d067
191 changed files with 34566 additions and 0 deletions
@@ -0,0 +1,136 @@
+import 'api_service.dart';
+import '../core/utils/app_logger.dart';
+import '../core/utils/file_utils.dart';
+import '../core/utils/time_flow_decoder.dart';
+
+/// 缩略图缓存条目
+class _ThumbCacheEntry {
+  final String imageUrl;
+  final DateTime expiresAt;
+
+  _ThumbCacheEntry({required this.imageUrl, required this.expiresAt});
+
+  bool get isExpired => DateTime.now().isAfter(expiresAt);
+}
+
+/// 缩略图服务 — 获取、解码、缓存缩略图 URL
+class ThumbnailService {
+  static ThumbnailService? _instance;
+  static ThumbnailService get instance {
+    _instance ??= ThumbnailService._();
+    return _instance!;
+  }
+
+  ThumbnailService._();
+
+  // 内存缓存: fileUri -> cache entry
+  final Map<String, _ThumbCacheEntry> _urlCache = {};
+
+  // 请求去重: fileUri -> in-flight Future
+  final Map<String, Future<String?>> _inFlightRequests = {};
+
+  /// 获取缩略图图片 URL
+  /// [fileUri] 文件的 relativePath（如 /path/to/file.jpg）
+  /// [contextHint] 可选，加速服务端 DB 查询
+  Future<String?> getThumbnailUrl({
+    required String fileUri,
+    String? contextHint,
+  }) async {
+    final cacheKey = fileUri;
+
+    // 1. 检查内存缓存
+    final cached = _urlCache[cacheKey];
+    if (cached != null && !cached.isExpired) {
+      return cached.imageUrl;
+    }
+    if (cached != null) {
+      _urlCache.remove(cacheKey);
+    }
+
+    // 2. 检查请求去重
+    final inFlight = _inFlightRequests[cacheKey];
+    if (inFlight != null) {
+      return inFlight;
+    }
+
+    // 3. 发起请求
+    final future = _fetchThumbnailUrl(fileUri, contextHint);
+    _inFlightRequests[cacheKey] = future;
+
+    try {
+      return await future;
+    } finally {
+      _inFlightRequests.remove(cacheKey);
+    }
+  }
+
+  Future<String?> _fetchThumbnailUrl(String fileUri, String? contextHint) async {
+    try {
+      final uri = FileUtils.toCloudreveUri(fileUri);
+      final headers = contextHint != null
+          ? <String, dynamic>{'X-Cr-Context-Hint': contextHint}
+          : null;
+
+      // _parseResponse 已提取 ApiResponse.data，response 即 {url, obfuscated, expires}
+      final response = await ApiService.instance.get<Map<String, dynamic>>(
+        '/file/thumb',
+        queryParameters: {'uri': uri},
+        headers: headers,
+      );
+
+      AppLogger.d('ThumbnailService: response for $fileUri = $response');
+
+      var url = response['url'] as String? ?? '';
+      final obfuscated = response['obfuscated'] as bool? ?? false;
+      final expiresStr = response['expires'] as String?;
+
+      // 解码混淆 URL
+      if (obfuscated && url.isNotEmpty) {
+        final decoded = TimeFlowDecoder.decodeTimeFlowString(url);
+        if (decoded == null) {
+          AppLogger.w('Failed to decode obfuscated thumbnail URL for $fileUri');
+          return null;
+        }
+        url = decoded;
+      }
+
+      if (url.isEmpty) return null;
+
+      AppLogger.d('ThumbnailService: resolved URL for $fileUri = $url');
+
+      // 解析过期时间，缓存提前 30 秒过期
+      DateTime expiresAt;
+      if (expiresStr != null) {
+        try {
+          expiresAt = DateTime.parse(expiresStr).subtract(const Duration(seconds: 30));
+        } catch (_) {
+          expiresAt = DateTime.now().add(const Duration(minutes: 5));
+        }
+      } else {
+        expiresAt = DateTime.now().add(const Duration(minutes: 5));
+      }
+
+      // 存入内存缓存
+      _urlCache[fileUri] = _ThumbCacheEntry(
+        imageUrl: url,
+        expiresAt: expiresAt,
+      );
+
+      return url;
+    } catch (e) {
+      AppLogger.d('ThumbnailService: failed to get thumbnail URL for $fileUri: $e');
+      return null;
+    }
+  }
+
+  /// 移除指定文件的缓存 URL
+  void evictUrl(String fileUri) {
+    _urlCache.remove(fileUri);
+  }
+
+  /// 清空所有缓存（目录切换时调用）
+  void clearAll() {
+    _urlCache.clear();
+    _inFlightRequests.clear();
+  }
+}