feat(content_management): implement loading, restoring, and deleting archived headlines

Author: fulleni

lib/content_management/bloc/archived_headlines/archived_headlines_bloc.dart

@@ -1,14 +1,118 @@
 import 'package:bloc/bloc.dart';
 import 'package:core/core.dart';
+import 'package:data_repository/data_repository.dart';
 import 'package:equatable/equatable.dart';
 
 part 'archived_headlines_event.dart';
 part 'archived_headlines_state.dart';
 
-class ArchivedHeadlinesBloc extends Bloc<ArchivedHeadlinesEvent, ArchivedHeadlinesState> {
-  ArchivedHeadlinesBloc() : super(ArchivedHeadlinesInitial()) {
-    on<ArchivedHeadlinesEvent>((event, emit) {
-      // TODO: implement event handler
-    });
+class ArchivedHeadlinesBloc
+    extends Bloc<ArchivedHeadlinesEvent, ArchivedHeadlinesState> {
+  ArchivedHeadlinesBloc({
+    required DataRepository<Headline> headlinesRepository,
+  })  : _headlinesRepository = headlinesRepository,
+        super(const ArchivedHeadlinesState()) {
+    on<LoadArchivedHeadlinesRequested>(_onLoadArchivedHeadlinesRequested);
+    on<RestoreHeadlineRequested>(_onRestoreHeadlineRequested);
+    on<DeleteHeadlineForeverRequested>(_onDeleteHeadlineForeverRequested);
+  }
+
+  final DataRepository<Headline> _headlinesRepository;
+
+  Future<void> _onLoadArchivedHeadlinesRequested(
+    LoadArchivedHeadlinesRequested event,
+    Emitter<ArchivedHeadlinesState> emit,
+  ) async {
+    emit(state.copyWith(status: ArchivedHeadlinesStatus.loading));
+    try {
+      final isPaginating = event.startAfterId != null;
+      final previousHeadlines = isPaginating ? state.headlines : <Headline>[];
+
+      final paginatedHeadlines = await _headlinesRepository.readAll(
+        filter: {'status': ContentStatus.archived.name},
+        sort: [const SortOption('updatedAt', SortOrder.desc)],
+        pagination: PaginationOptions(
+          cursor: event.startAfterId,
+          limit: event.limit,
+        ),
+      );
+      emit(
+        state.copyWith(
+          status: ArchivedHeadlinesStatus.success,
+          headlines: [...previousHeadlines, ...paginatedHeadlines.items],
+          cursor: paginatedHeadlines.cursor,
+          hasMore: paginatedHeadlines.hasMore,
+        ),
+      );
+    } on HttpException catch (e) {
+      emit(
+        state.copyWith(
+          status: ArchivedHeadlinesStatus.failure,
+          exception: e,
+        ),
+      );
+    } catch (e) {
+      emit(
+        state.copyWith(
+          status: ArchivedHeadlinesStatus.failure,
+          exception: UnknownException('An unexpected error occurred: $e'),
+        ),
+      );
+    }
+  }
+
+  Future<void> _onRestoreHeadlineRequested(
+    RestoreHeadlineRequested event,
+    Emitter<ArchivedHeadlinesState> emit,
+  ) async {
+    final originalHeadlines = List<Headline>.from(state.headlines);
+    final headlineIndex = originalHeadlines.indexWhere((h) => h.id == event.id);
+    if (headlineIndex == -1) return;
+
+    final headlineToRestore = originalHeadlines[headlineIndex];
+    final updatedHeadlines = originalHeadlines..removeAt(headlineIndex);
+
+    emit(state.copyWith(headlines: updatedHeadlines));
+
+    try {
+      await _headlinesRepository.update(
+        id: event.id,
+        item: headlineToRestore.copyWith(status: ContentStatus.active),
+      );
+    } on HttpException catch (e) {
+      emit(state.copyWith(headlines: originalHeadlines, exception: e));
+    } catch (e) {
+      emit(
+        state.copyWith(
+          headlines: originalHeadlines,
+          exception: UnknownException('An unexpected error occurred: $e'),
+        ),
+      );
+    }
+  }
+
+  Future<void> _onDeleteHeadlineForeverRequested(
+    DeleteHeadlineForeverRequested event,
+    Emitter<ArchivedHeadlinesState> emit,
+  ) async {
+    final originalHeadlines = List<Headline>.from(state.headlines);
+    final headlineIndex = originalHeadlines.indexWhere((h) => h.id == event.id);
+    if (headlineIndex == -1) return;
+
+    final updatedHeadlines = originalHeadlines..removeAt(headlineIndex);
+    emit(state.copyWith(headlines: updatedHeadlines));
+
+    try {
+      await _headlinesRepository.delete(id: event.id);
+    } on HttpException catch (e) {
+      emit(state.copyWith(headlines: originalHeadlines, exception: e));
+    } catch (e) {
+      emit(
+        state.copyWith(
+          headlines: originalHeadlines,
+          exception: UnknownException('An unexpected error occurred: $e'),
+        ),
+      );
+    }
   }
 }