feat: persist tmdb artwork urls instead of blobs

lib/core/storage/media_library_store.dart

@@ -1,6 +1,5 @@
 import 'dart:convert';
 import 'dart:io';
-import 'dart:typed_data';
 
 import 'package:path/path.dart' as path;
 import 'package:sqflite/sqflite.dart';
@@ -22,7 +21,7 @@ class MediaLibraryStore {
     );
     _database = await openDatabase(
       databasePath,
-      version: 3,
+      version: 4,
       onCreate: (db, _) async {
         await _createSchema(db);
       },
@@ -104,18 +103,6 @@ class MediaLibraryStore {
     return rows.map(_itemFromRow).toList();
   }
 
-  Future<Uint8List?> posterBytes(String libraryID, String fileID) async {
-    final rows = await (await _db).query(
-      'media_items',
-      columns: const ['poster'],
-      where: 'library_id = ? AND file_id = ?',
-      whereArgs: [libraryID, fileID],
-      limit: 1,
-    );
-    final value = rows.isEmpty ? null : rows.first['poster'];
-    return value is Uint8List ? value : null;
-  }
-
   Future<void> saveLibraries(List<MediaLibraryDefinition> libraries) async {
     final db = await _db;
     await db.transaction((txn) async {
@@ -209,9 +196,33 @@ class MediaLibraryStore {
         await txn.execute(
           'INSERT OR REPLACE INTO media_library_sources SELECT * FROM imported_backup.media_library_sources',
         );
-        await txn.execute(
-          'INSERT OR REPLACE INTO media_items SELECT * FROM imported_backup.media_items',
+        final importedColumns = await _tableColumns(
+          txn,
+          'imported_backup',
+          'media_items',
         );
+        final importedPosterPath = importedColumns.contains('poster_path')
+            ? 'poster_path'
+            : 'NULL';
+        final importedBackdropPath = importedColumns.contains('backdrop_path')
+            ? 'backdrop_path'
+            : 'NULL';
+        await txn.execute('''
+          INSERT OR REPLACE INTO media_items (
+            library_id, file_id, resource_path, cloud_name, file_size, gcid,
+            file_type, tmdb_id, media_kind, title, original_title,
+            release_date, overview, poster_path, backdrop_path, poster, backdrop,
+            has_chinese_audio, has_chinese_subtitle, collection_id,
+            collection_name, updated_at
+          )
+          SELECT
+            library_id, file_id, resource_path, cloud_name, file_size, gcid,
+            file_type, tmdb_id, media_kind, title, original_title,
+            release_date, overview, $importedPosterPath, $importedBackdropPath,
+            NULL, NULL, has_chinese_audio, has_chinese_subtitle, collection_id,
+            collection_name, updated_at
+          FROM imported_backup.media_items
+        ''');
       });
     } finally {
       await db.execute('DETACH DATABASE imported_backup');
@@ -219,14 +230,14 @@ class MediaLibraryStore {
     return optimizeStorage();
   }
 
-  /// Reclaims space used by imported backdrop BLOBs. Posters remain available
-  /// for offline poster walls; backdrops can always be fetched from TMDB again.
+  /// TMDB artwork is stored by address.  This removes legacy binary artwork
+  /// from imported databases, while retaining every media and scrape record.
   Future<MediaLibraryStorageStats> optimizeStorage() async {
     final db = await _db;
     final before = await _databaseBytes(db.path);
-    final removedBackdrops = await db.rawUpdate(
-      'UPDATE media_items SET backdrop = NULL WHERE backdrop IS NOT NULL',
-    );
+    final removedArtwork = await db.rawUpdate('''UPDATE media_items
+         SET poster = NULL, backdrop = NULL
+         WHERE poster IS NOT NULL OR backdrop IS NOT NULL''');
     await db.execute('PRAGMA wal_checkpoint(TRUNCATE)');
     await db.execute('PRAGMA optimize');
     await db.execute('VACUUM');
@@ -234,7 +245,7 @@ class MediaLibraryStore {
     return MediaLibraryStorageStats(
       beforeBytes: before,
       afterBytes: after,
-      removedBackdropCount: removedBackdrops,
+      removedArtworkCount: removedArtwork,
     );
   }
 
@@ -468,6 +479,8 @@ class MediaLibraryStore {
         original_title TEXT NOT NULL,
         release_date TEXT NOT NULL,
         overview TEXT NOT NULL,
+        poster_path TEXT,
+        backdrop_path TEXT,
         poster BLOB,
         backdrop BLOB,
         has_chinese_audio INTEGER NOT NULL DEFAULT 0,
@@ -508,6 +521,8 @@ class MediaLibraryStore {
     await db.execute(
       'CREATE INDEX IF NOT EXISTS idx_file_index_gcid ON file_index(gcid)',
     );
+    await _ensureColumn(db, 'media_items', 'poster_path', 'TEXT');
+    await _ensureColumn(db, 'media_items', 'backdrop_path', 'TEXT');
   }
 
   MediaLibraryItem _itemFromRow(Map<String, Object?> row) {
@@ -525,6 +540,8 @@ class MediaLibraryStore {
       'originalTitle': row['original_title'],
       'releaseDate': row['release_date'],
       'overview': row['overview'],
+      'posterPath': row['poster_path'],
+      'backdropPath': row['backdrop_path'],
       'hasChineseAudio': row['has_chinese_audio'] == 1,
       'hasChineseSubtitle': row['has_chinese_subtitle'] == 1,
       'collectionID': row['collection_id'],
@@ -547,6 +564,8 @@ class MediaLibraryStore {
     'original_title': item.originalTitle,
     'release_date': item.releaseDate,
     'overview': item.overview,
+    'poster_path': item.posterPath,
+    'backdrop_path': item.backdropPath,
     'has_chinese_audio': item.hasChineseAudio ? 1 : 0,
     'has_chinese_subtitle': item.hasChineseSubtitle ? 1 : 0,
     'collection_id': item.collectionID,
@@ -595,6 +614,8 @@ class MediaLibraryStore {
     'original_title',
     'release_date',
     'overview',
+    'poster_path',
+    'backdrop_path',
     'has_chinese_audio',
     'has_chinese_subtitle',
     'collection_id',
@@ -611,17 +632,41 @@ class MediaLibraryStore {
     }
     return bytes;
   }
+
+  Future<Set<String>> _tableColumns(
+    DatabaseExecutor db,
+    String schema,
+    String table,
+  ) async {
+    final rows = await db.rawQuery('PRAGMA $schema.table_info($table)');
+    return rows
+        .map((row) => row['name']?.toString())
+        .whereType<String>()
+        .toSet();
+  }
+
+  Future<void> _ensureColumn(
+    DatabaseExecutor db,
+    String table,
+    String column,
+    String definition,
+  ) async {
+    final columns = await _tableColumns(db, 'main', table);
+    if (!columns.contains(column)) {
+      await db.execute('ALTER TABLE $table ADD COLUMN $column $definition');
+    }
+  }
 }
 
 class MediaLibraryStorageStats {
   final int beforeBytes;
   final int afterBytes;
-  final int removedBackdropCount;
+  final int removedArtworkCount;
 
   const MediaLibraryStorageStats({
     required this.beforeBytes,
     required this.afterBytes,
-    required this.removedBackdropCount,
+    required this.removedArtworkCount,
   });
 
   int get reclaimedBytes => (beforeBytes - afterBytes).clamp(0, beforeBytes);

lib/pages/media_library_page.dart

@@ -1,5 +1,3 @@
-import 'dart:typed_data';
-
 import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:file_picker/file_picker.dart';
@@ -1570,19 +1568,15 @@ class _MediaCollectionTile extends ConsumerWidget {
                         border: Border.all(color: cs.border),
                       ),
                       clipBehavior: Clip.antiAlias,
-                      child: FutureBuilder<Uint8List?>(
-                        future: ref
-                            .read(mediaLibraryProvider.notifier)
-                            .posterBytes(item),
-                        builder: (context, snapshot) {
-                          if (snapshot.data != null) {
-                            return Image.memory(
-                              snapshot.data!,
-                              fit: BoxFit.cover,
-                            );
-                          }
-                          if (posterURL != null) {
-                            return Image.network(
+                      child: posterURL == null
+                          ? Center(
+                              child: Icon(
+                                Icons.collections_bookmark_rounded,
+                                color: cs.mutedForeground,
+                                size: 34,
+                              ),
+                            )
+                          : Image.network(
                               posterURL,
                               fit: BoxFit.cover,
                               errorBuilder: (_, _, _) => Center(
@@ -1592,17 +1586,7 @@ class _MediaCollectionTile extends ConsumerWidget {
                                   size: 34,
                                 ),
                               ),
-                            );
-                          }
-                          return Center(
-                            child: Icon(
-                              Icons.collections_bookmark_rounded,
-                              color: cs.mutedForeground,
-                              size: 34,
                             ),
-                          );
-                        },
-                      ),
                     ),
                     Positioned(
                       right: 7,
@@ -1715,28 +1699,14 @@ class _MediaPosterTile extends ConsumerWidget {
                           border: Border.all(color: cs.border),
                         ),
                         clipBehavior: Clip.antiAlias,
-                        child: FutureBuilder<Uint8List?>(
-                          future: ref
-                              .read(mediaLibraryProvider.notifier)
-                              .posterBytes(item),
-                          builder: (context, snapshot) {
-                            if (snapshot.data != null) {
-                              return Image.memory(
-                                snapshot.data!,
-                                fit: BoxFit.cover,
-                              );
-                            }
-                            if (posterURL != null) {
-                              return Image.network(
+                        child: posterURL == null
+                            ? _posterFallback(cs, isSeries)
+                            : Image.network(
                                 posterURL,
                                 fit: BoxFit.cover,
                                 errorBuilder: (_, _, _) =>
                                     _posterFallback(cs, isSeries),
-                              );
-                            }
-                            return _posterFallback(cs, isSeries);
-                          },
-                        ),
+                              ),
                       ),
                       if (work.resources.length > 1)
                         Positioned(
@@ -1992,23 +1962,14 @@ class _MediaDetailPanelState extends ConsumerState<_MediaDetailPanel> {
           height: 270,
           child: ClipRRect(
             borderRadius: BorderRadius.circular(6),
-            child: FutureBuilder<Uint8List?>(
-              future: ref.read(mediaLibraryProvider.notifier).posterBytes(item),
-              builder: (context, snapshot) {
-                if (snapshot.data != null) {
-                  return Image.memory(snapshot.data!, fit: BoxFit.cover);
-                }
-                if (posterURL != null) {
-                  return Image.network(
+            child: posterURL == null
+                ? _detailPosterFallback(cs, isSeries)
+                : Image.network(
                     posterURL,
                     fit: BoxFit.cover,
                     errorBuilder: (_, _, _) =>
                         _detailPosterFallback(cs, isSeries),
-                  );
-                }
-                return _detailPosterFallback(cs, isSeries);
-              },
-            ),
+                  ),
           ),
         ),
         const SizedBox(width: 18),

lib/providers/media_library_provider.dart

@@ -1,5 +1,4 @@
 import 'dart:async';
-import 'dart:typed_data';
 
 import 'package:flutter_riverpod/legacy.dart';
 
@@ -86,7 +85,6 @@ class MediaLibraryState {
 class MediaLibraryNotifier extends StateNotifier<MediaLibraryState> {
   GuangyaAPI? _api;
   final _store = MediaLibraryStore();
-  final _posterRequests = <String, Future<Uint8List?>>{};
   bool _loaded = false;
   bool _cancelScan = false;
 
@@ -251,9 +249,9 @@ class MediaLibraryNotifier extends StateNotifier<MediaLibraryState> {
     try {
       final stats = await _store.optimizeStorage();
       state = state.copyWith(
-        statusMessage: stats.removedBackdropCount == 0
+        statusMessage: stats.removedArtworkCount == 0
             ? '本地刮削数据库已是最优状态'
-            : '已清理 ${stats.removedBackdropCount} 张背景图，回收 ${_formatBytes(stats.reclaimedBytes)}',
+            : '已清理 ${stats.removedArtworkCount} 条本地图片缓存，回收 ${_formatBytes(stats.reclaimedBytes)}',
       );
     } catch (error) {
       state = state.copyWith(errorMessage: '数据库优化失败：$error');
@@ -408,17 +406,6 @@ class MediaLibraryNotifier extends StateNotifier<MediaLibraryState> {
       ..sort((a, b) => a.title.toLowerCase().compareTo(b.title.toLowerCase()));
   }
 
-  Future<Uint8List?> posterBytes(MediaLibraryItem item) {
-    final key = '${item.libraryID}:${item.file.id}';
-    return _posterRequests.putIfAbsent(key, () async {
-      final bytes = await _store.posterBytes(item.libraryID, item.file.id);
-      if (_posterRequests.length > 48) {
-        _posterRequests.remove(_posterRequests.keys.first);
-      }
-      return bytes;
-    });
-  }
-
   Future<MediaLibraryItem> applyTMDBMatch(
     MediaLibraryItem item,
     Map<String, dynamic> candidate,