feat: instant tag suggestions, persistent disk cache, history limit settings, match highlighting and category badges (v2.0.9)

test/backend/search_service_test.dart

@@ -21,7 +21,7 @@ class FakeSearchRepository implements SearchRepository {
   }
 
   @override
-  Future<Result<void>> save(SearchHistory history) async {
+  Future<Result<void>> save(SearchHistory history, {int maxItems = 500}) async {
     items.add(history);
     return const Success(null);
   }

test/backend/tag_cache_service_test.dart

@@ -0,0 +1,149 @@
+import 'dart:io';
+
+import 'package:flutter_test/flutter_test.dart';
+import 'package:gel_rule_app/backend/models/tag_suggestion.dart';
+import 'package:gel_rule_app/backend/services/tag_cache_service.dart';
+
+void main() {
+  late Directory tempDir;
+  late String cacheFilePath;
+  late TagCacheService cacheService;
+
+  setUp(() async {
+    tempDir = await Directory.systemTemp.createTemp('lunaris_test_tag_cache');
+    cacheFilePath = '${tempDir.path}/test_tags.json';
+    cacheService = TagCacheService(customPath: cacheFilePath);
+    await cacheService.init();
+  });
+
+  tearDown(() async {
+    if (await tempDir.exists()) {
+      await tempDir.delete(recursive: true);
+    }
+  });
+
+  test('TagSuggestion toJson and fromJson work correctly', () {
+    const item = TagSuggestion(
+      name: 'hatsune_miku',
+      category: TagCategory.character,
+      postCount: 154200,
+      providerId: 'danbooru',
+    );
+    final json = item.toJson();
+    final restored = TagSuggestion.fromJson(json);
+
+    expect(restored.name, 'hatsune_miku');
+    expect(restored.category, TagCategory.character);
+    expect(restored.postCount, 154200);
+    expect(restored.providerId, 'danbooru');
+  });
+
+  test('findLocal returns matching tags instantaneously', () async {
+    await cacheService.cacheTags([
+      const TagSuggestion(
+        name: 'cat_ears',
+        category: TagCategory.general,
+        postCount: 1000,
+        providerId: 'gelbooru',
+      ),
+      const TagSuggestion(
+        name: 'caterpillar',
+        category: TagCategory.general,
+        postCount: 200,
+        providerId: 'gelbooru',
+      ),
+      const TagSuggestion(
+        name: 'dog_tail',
+        category: TagCategory.general,
+        postCount: 800,
+        providerId: 'gelbooru',
+      ),
+    ]);
+
+    final matches = cacheService.findLocal('cat');
+    expect(matches.length, 2);
+    expect(matches.first.name, 'cat_ears');
+    expect(matches[1].name, 'caterpillar');
+
+    final dogMatches = cacheService.findLocal('dog');
+    expect(dogMatches.length, 1);
+    expect(dogMatches.first.name, 'dog_tail');
+  });
+
+  test('findLocal sanitizes parentheses in prefix', () async {
+    await cacheService.cacheTags([
+      const TagSuggestion(
+        name: 'cat_ears',
+        category: TagCategory.general,
+        postCount: 1000,
+        providerId: 'gelbooru',
+      ),
+    ]);
+
+    final matches = cacheService.findLocal('(cat');
+    expect(matches.length, 1);
+    expect(matches.first.name, 'cat_ears');
+  });
+
+  test('findLocal respects priority tags from search history', () async {
+    await cacheService.cacheTags([
+      const TagSuggestion(
+        name: 'cat_girl',
+        category: TagCategory.general,
+        postCount: 5000,
+        providerId: 'gelbooru',
+      ),
+      const TagSuggestion(
+        name: 'cat_costume',
+        category: TagCategory.general,
+        postCount: 50,
+        providerId: 'gelbooru',
+      ),
+    ]);
+
+    // Priority tag 'cat_costume' should appear first despite lower postCount
+    final matches = cacheService.findLocal(
+      'cat',
+      priorityTags: ['cat_costume'],
+    );
+    expect(matches.first.name, 'cat_costume');
+    expect(matches[1].name, 'cat_girl');
+  });
+
+  test('flush saves tags to file and reloading restores them', () async {
+    await cacheService.cacheTags([
+      const TagSuggestion(
+        name: 'genshin_impact',
+        category: TagCategory.copyright,
+        postCount: 300000,
+        providerId: 'danbooru',
+      ),
+    ]);
+    await cacheService.flush();
+
+    final reloadedService = TagCacheService(customPath: cacheFilePath);
+    await reloadedService.init();
+
+    final results = reloadedService.findLocal('genshin');
+    expect(results.length, 1);
+    expect(results.first.name, 'genshin_impact');
+    expect(results.first.category, TagCategory.copyright);
+  });
+
+  test('clear removes tags from memory and disk', () async {
+    await cacheService.cacheTags([
+      const TagSuggestion(
+        name: 'raiden_shogun',
+        category: TagCategory.character,
+        postCount: 45000,
+        providerId: 'danbooru',
+      ),
+    ]);
+    await cacheService.flush();
+    expect(File(cacheFilePath).existsSync(), isTrue);
+
+    await cacheService.clear();
+    expect(cacheService.tagCount, 0);
+    expect(File(cacheFilePath).existsSync(), isFalse);
+  });
+}