基础实现代码框架先上，后面慢慢改逻辑

2026-08-23 19:24:16 +08:00
parent 6c4e77ca00
commit 9a60441e04
9 changed files with 446 additions and 1 deletions
@@ -0,0 +1,74 @@
+// lib/metadata/metadata_service.dart
+import 'dart:io';
+import 'metadata_model.dart';
+import 'metadata_reader.dart';
+import 'metadata_normalizer.dart';
+import 'metadata_cache.dart';
+
+class MetadataService {
+  static final MetadataService _instance = MetadataService._internal();
+  factory MetadataService() => _instance;
+  MetadataService._internal();
+
+  final MetadataReader _reader = MetadataReader();
+  final MetadataNormalizer _normalizer = MetadataNormalizer();
+  final MetadataCache _cache = MetadataCache();
+
+  /// 获取歌曲的最终元数据（优先缓存，否则读取文件）
+  Future<FinalMetadata> getMetadata({
+    required String filePath,
+    required String fileName,
+    required String fileId,
+    bool forceRefresh = false,
+  }) async {
+    // 1. 尝试从缓存读取
+    if (!forceRefresh) {
+      final cached = await _cache.get(fileId);
+      if (cached != null && cached.isNotEmpty) {
+        return cached;
+      }
+    }
+
+    // 2. 检查文件是否存在
+    final file = File(filePath);
+    if (!await file.exists()) {
+      // 文件不存在，返回基于文件名的推断
+      return _fallbackFromFileName(fileName);
+    }
+
+    // 3. 从文件读取原始元数据
+    final raw = await _reader.readRawMetadata(file);
+
+    // 4. 标准化
+    final normalized = _normalizer.normalize(
+      raw,
+      fileName: fileName,
+      filePath: filePath,
+    );
+
+    // 5. 评估（第一阶段直接接受）
+    final history = await _cache.getHistory(normalized.artist, limit: 10);
+    final candidate = _normalizer.evaluate(normalized, history);
+
+    // 6. 决策
+    final finalMetadata = _normalizer.decide(candidate);
+
+    // 7. 写入缓存
+    if (finalMetadata.isNotEmpty) {
+      await _cache.put(fileId, finalMetadata);
+    }
+
+    return finalMetadata;
+  }
+
+  /// Fallback：从文件名推断
+  FinalMetadata _fallbackFromFileName(String fileName) {
+    final dotIndex = fileName.lastIndexOf('.');
+    final title = dotIndex > 0 ? fileName.substring(0, dotIndex) : fileName;
+    return FinalMetadata(
+      title: title,
+      artist: '未知艺术家',
+      source: 'filename',
+    );
+  }
+}