feat: Enhance search functionality with initial query parameters and infinite scrolling

lib/features/novel/providers/novels_provider.dart

@@ -23,11 +23,40 @@ class BrowseParams {
     this.page = 1,
   });
 
+  String? _normalizedStatus() {
+    final raw = status?.trim();
+    if (raw == null || raw.isEmpty) return null;
+    switch (raw.toLowerCase()) {
+      case 'ongoing':
+        return 'Đang ra';
+      case 'completed':
+        return 'Hoàn thành';
+      case 'hiatus':
+        return 'Tạm ngưng';
+      default:
+        return raw;
+    }
+  }
+
+  String _normalizedSort() {
+    final raw = sort.trim();
+    if (raw.isEmpty) return 'latest';
+    switch (raw.toLowerCase()) {
+      case 'latest':
+      case 'popular':
+      case 'rating':
+      case 'name':
+        return raw.toLowerCase();
+      default:
+        return 'latest';
+    }
+  }
+
   Map<String, dynamic> toQueryParams() => {
         if (query != null && query!.isNotEmpty) 'q': query,
         if (genre != null) 'genre': genre,
-        if (status != null) 'status': status,
-        'sort': sort,
+        if (_normalizedStatus() != null) 'status': _normalizedStatus(),
+        'sort': _normalizedSort(),
         'page': page.toString(),
         'limit': '20',
       };
@@ -56,18 +85,39 @@ class BrowseResult {
   final int totalCount;
   final int totalPages;
   final int currentPage;
+  final bool isLoadingMore;
 
   const BrowseResult({
     required this.items,
     required this.totalCount,
     required this.totalPages,
     required this.currentPage,
+    this.isLoadingMore = false,
   });
+
+  bool get hasMore => currentPage < totalPages;
+
+  BrowseResult copyWith({
+    List<NovelModel>? items,
+    int? totalCount,
+    int? totalPages,
+    int? currentPage,
+    bool? isLoadingMore,
+  }) {
+    return BrowseResult(
+      items: items ?? this.items,
+      totalCount: totalCount ?? this.totalCount,
+      totalPages: totalPages ?? this.totalPages,
+      currentPage: currentPage ?? this.currentPage,
+      isLoadingMore: isLoadingMore ?? this.isLoadingMore,
+    );
+  }
 }
 
 class NovelsNotifier extends StateNotifier<AsyncValue<BrowseResult>> {
   final Ref _ref;
   BrowseParams _params = const BrowseParams();
+  bool _isLoadingMore = false;
 
   NovelsNotifier(this._ref) : super(const AsyncValue.loading()) {
     fetch();
@@ -75,25 +125,53 @@ class NovelsNotifier extends StateNotifier<AsyncValue<BrowseResult>> {
 
   BrowseParams get params => _params;
 
+  Future<BrowseResult> _fetchPage(BrowseParams params) async {
+    final client = _ref.read(apiClientProvider);
+    final res = await client.dio.get('/api/novels/browse', queryParameters: params.toQueryParams());
+    final data = res.data as Map<String, dynamic>;
+    return BrowseResult(
+      items: (data['items'] as List).map((e) => NovelModel.fromJson(e as Map<String, dynamic>)).toList(),
+      totalCount: (data['totalCount'] as num?)?.toInt() ?? 0,
+      totalPages: (data['totalPages'] as num?)?.toInt() ?? 1,
+      currentPage: (data['currentPage'] as num?)?.toInt() ?? params.page,
+    );
+  }
+
   Future<void> fetch({BrowseParams? params}) async {
     if (params != null) _params = params;
     state = const AsyncValue.loading();
     try {
-      final client = _ref.read(apiClientProvider);
-      final res = await client.dio.get('/api/novels/browse', queryParameters: _params.toQueryParams());
-      final data = res.data as Map<String, dynamic>;
-      state = AsyncValue.data(BrowseResult(
-        items: (data['items'] as List).map((e) => NovelModel.fromJson(e as Map<String, dynamic>)).toList(),
-        totalCount: data['totalCount'] as int,
-        totalPages: data['totalPages'] as int,
-        currentPage: data['currentPage'] as int,
-      ));
+      final firstPageParams = _params.copyWith(page: 1);
+      final result = await _fetchPage(firstPageParams);
+      _params = firstPageParams;
+      state = AsyncValue.data(result);
     } catch (e, st) {
       state = AsyncValue.error(e, st);
     }
   }
 
   Future<void> updateParams(BrowseParams params) => fetch(params: params);
+
+  Future<void> loadNextPage() async {
+    final current = state.valueOrNull;
+    if (current == null || !current.hasMore || _isLoadingMore) return;
+
+    _isLoadingMore = true;
+    state = AsyncValue.data(current.copyWith(isLoadingMore: true));
+
+    try {
+      final nextParams = _params.copyWith(page: current.currentPage + 1);
+      final nextPage = await _fetchPage(nextParams);
+      _params = nextParams;
+
+      final merged = [...current.items, ...nextPage.items];
+      state = AsyncValue.data(nextPage.copyWith(items: merged, isLoadingMore: false));
+    } catch (e, st) {
+      state = AsyncValue.error(e, st);
+    } finally {
+      _isLoadingMore = false;
+    }
+  }
 }
 
 final novelsProvider = StateNotifierProvider<NovelsNotifier, AsyncValue<BrowseResult>>((ref) {