import 'package:flutter_test/flutter_test.dart';
import 'package:bookshelf_flutter/bloc/library/library_bloc.dart';
import 'package:bookshelf_flutter/bloc/library/library_event.dart';
import 'package:bookshelf_flutter/bloc/library/library_state.dart';
import 'package:bookshelf_flutter/models/models.dart';

void main() {
  group('LibraryBloc', () {
    late LibraryBloc libraryBloc;

    setUp(() {
      libraryBloc = LibraryBloc();
    });

    tearDown(() {
      libraryBloc.close();
    });

    test('initial state is LibraryState.initial()', () {
      expect(libraryBloc.state, isA<LibraryState>());
      expect(libraryBloc.state.isLoading, true);
    });

    group('LoadBooks', () {
      test('emits [LibraryState] with books when LoadBooks is added', () async {
        final expected = [
          isA<LibraryState>()
              .having((state) => state.isLoading, 'isLoading', false)
              .having((state) => state.books.isNotEmpty, 'books.isNotEmpty', true),
        ];

        expectLater(libraryBloc.stream, emitsInOrder(expected));

        libraryBloc.add(const LoadBooks());
      });
    });

    group('SearchBooks', () {
      test('filters books by title', () async {
        libraryBloc.add(const LoadBooks());
        await Future.delayed(Duration.zero);

        libraryBloc.add(const SearchBooks('Гэтсби'));
        await Future.delayed(Duration.zero);

        expect(libraryBloc.state.filteredBooks.length, 1);
        expect(libraryBloc.state.filteredBooks.first.title, contains('Гэтсби'));
      });

      test('filters books by author', () async {
        libraryBloc.add(const LoadBooks());
        await Future.delayed(Duration.zero);

        libraryBloc.add(const SearchBooks('Оруэлл'));
        await Future.delayed(Duration.zero);

        expect(libraryBloc.state.filteredBooks.length, 1);
        expect(libraryBloc.state.filteredBooks.first.author, contains('Оруэлл'));
      });

      test('filters books by genre', () async {
        libraryBloc.add(const LoadBooks());
        await Future.delayed(Duration.zero);

        libraryBloc.add(const SearchBooks('Fantasy'));
        await Future.delayed(Duration.zero);

        expect(libraryBloc.state.filteredBooks.isNotEmpty, true);
      });

      test('returns empty list when no matches found', () async {
        libraryBloc.add(const LoadBooks());
        await Future.delayed(Duration.zero);

        libraryBloc.add(const SearchBooks('NonExistent'));
        await Future.delayed(Duration.zero);

        expect(libraryBloc.state.filteredBooks.length, 0);
      });
    });

    group('BookSelected', () {
      test('updates selectedBook in state', () async {
        libraryBloc.add(const LoadBooks());
        await Future.delayed(Duration.zero);

        final book = libraryBloc.state.books.first;
        libraryBloc.add(BookSelected(book));
        await Future.delayed(Duration.zero);

        expect(libraryBloc.state.selectedBook?.id, book.id);
      });
    });

    group('FilterByStatus', () {
      test('filters books by status', () async {
        libraryBloc.add(const LoadBooks());
        await Future.delayed(Duration.zero);

        libraryBloc.add(const FilterByStatus(BookStatus.reading));
        await Future.delayed(Duration.zero);

        expect(libraryBloc.state.filteredBooks.every((book) => book.status == BookStatus.reading), true);
        expect(libraryBloc.state.statusFilter, BookStatus.reading);
      });
    });

    group('ClearFilters', () {
      test('clears search query and shows all books', () async {
        libraryBloc.add(const LoadBooks());
        await Future.delayed(Duration.zero);

        libraryBloc.add(const SearchBooks('test'));
        await Future.delayed(Duration.zero);

        libraryBloc.add(const ClearFilters());
        await Future.delayed(Duration.zero);

        expect(libraryBloc.state.searchQuery, '');
        expect(libraryBloc.state.filteredBooks.length, libraryBloc.state.books.length);
      });
    });
  });
}