通知中心封面图显示

部分界面的信息更新
缓存系统初步引入
即将进入播放列表更新

lib/metadata/metadata_cache.dart

@@ -16,6 +16,10 @@ class MetadataCache {
     _cache[fileId] = metadata;
   }
 
+  Future<void> remove(String fileId) async {
+    _cache.remove(fileId);
+  }
+
   Future<List<Map<String, dynamic>>> getHistory(String artist,
       {int limit = 10}) async {
     return [];

lib/metadata/metadata_reader.dart

@@ -1,5 +1,6 @@
 // lib/metadata/metadata_reader.dart
 import 'dart:io';
+import 'dart:typed_data';
 import 'package:flutter/foundation.dart';
 import 'package:audio_metadata_reader/audio_metadata_reader.dart' as amr;
 import 'metadata_model.dart';
@@ -7,13 +8,25 @@ import 'metadata_model.dart';
 class MetadataReader {
   Future<RawMetadata> readRawMetadata(File file) async {
     try {
-      // ⭐ getImage: true 读取封面图
       final meta = amr.readMetadata(file, getImage: true);
 
-      // ⭐ 提取第一张图片
+      debugPrint('📢 [MetadataReader] pictures count: ${meta.pictures.length}');
+
       Uint8List? artwork;
-      if (meta.pictures != null && meta.pictures!.isNotEmpty) {
-        artwork = meta.pictures.first.bytes;
+      if (meta.pictures.isNotEmpty) {
+        try {
+          final pic = meta.pictures.first;
+          // 尝试获取图片数据，兼容不同字段名
+          artwork = (pic as dynamic).bytes ?? (pic as dynamic).data;
+          if (artwork != null) {
+            debugPrint(
+                '📢 [MetadataReader] artwork extracted: ${artwork.length} bytes');
+          }
+        } catch (e) {
+          debugPrint('⚠️ [MetadataReader] artwork extraction failed: $e');
+        }
+      } else {
+        debugPrint('📢 [MetadataReader] no artwork found');
       }
 
       return RawMetadata(

lib/metadata/metadata_service.dart

@@ -1,6 +1,6 @@
 // lib/metadata/metadata_service.dart
-import 'dart:io'; // ⭐ 添加这一行
-import 'dart:typed_data'; // ⭐ 如果已经有更好
+import 'dart:io';
+import 'dart:typed_data';
 import 'package:flutter/foundation.dart';
 import '../database/song_database.dart';
 import 'metadata_model.dart';
@@ -32,6 +32,17 @@ class MetadataService {
     return LocalFileProvider();
   }
 
+  /// 公开给 AudioService 使用（用于清除缓存时获取文件）
+  FileProvider getProviderForUrl(String url) {
+    return _getProvider(url);
+  }
+
+  /// 清除内存缓存
+  Future<void> clearCache(String fileId) async {
+    await _memoryCache.remove(fileId);
+    debugPrint('🗑️ [MetadataService] memory cache cleared: $fileId');
+  }
+
   Future<FinalMetadata> getMetadata({
     required String url,
     required String fileName,
@@ -111,6 +122,8 @@ class MetadataService {
     final history = await _db.getSongsByArtist(normalized.artist, limit: 10);
     final candidate = _normalizer.evaluate(normalized, history);
     final finalMetadata = _normalizer.decide(candidate);
+    debugPrint(
+        '📢 [MetadataService] finalMetadata.artwork is ${finalMetadata.artwork != null ? 'not null (${finalMetadata.artwork!.length} bytes)' : 'null'}');
 
     // 7. 保存封面图到本地
     String? artworkPath;