refactor: create separate BLoCs for each screen with comprehensive tests

- Created 8 separate BLoCs (Home, Library, BookDetails, AddBook, Scanner, Categories, Wishlist, Settings)
- Each BLoC has its own event, state, and bloc files
- Added 70 comprehensive tests covering all BLoC functionality
- All tests passing (70/70)
- Fixed linting issues and updated deprecated APIs
- Improved code organization and maintainability

bookshelf_flutter/test/bloc/add_book/add_book_bloc_test.dart

@@ -0,0 +1,178 @@
+import 'package:flutter_test/flutter_test.dart';
+import 'package:bookshelf_flutter/bloc/add_book/add_book_bloc.dart';
+import 'package:bookshelf_flutter/bloc/add_book/add_book_event.dart';
+import 'package:bookshelf_flutter/bloc/add_book/add_book_state.dart';
+import 'package:bookshelf_flutter/models/models.dart';
+
+void main() {
+  group('AddBookBloc', () {
+    late AddBookBloc addBookBloc;
+
+    setUp(() {
+      addBookBloc = AddBookBloc();
+    });
+
+    tearDown(() {
+      addBookBloc.close();
+    });
+
+    test('initial state is AddBookState.initial()', () {
+      expect(addBookBloc.state, isA<AddBookState>());
+      expect(addBookBloc.state.isLoading, false);
+    });
+
+    group('InitializeForm', () {
+      test('initializes form with prefilled data', () async {
+        final prefilledData = {
+          'title': 'Test Book',
+          'author': 'Test Author',
+          'genre': 'Test Genre',
+          'annotation': 'Test annotation',
+          'coverUrl': 'https://example.com/cover.jpg',
+          'pages': 200,
+          'language': 'English',
+          'publishedYear': 2020,
+          'rating': 4.5,
+          'status': BookStatus.reading,
+          'progress': 50,
+          'isFavorite': true,
+        };
+
+        addBookBloc.add(InitializeForm(prefilledData));
+        await Future.delayed(Duration.zero);
+
+        expect(addBookBloc.state.title, 'Test Book');
+        expect(addBookBloc.state.author, 'Test Author');
+        expect(addBookBloc.state.genre, 'Test Genre');
+        expect(addBookBloc.state.isFavorite, true);
+        expect(addBookBloc.state.pages, 200);
+      });
+
+      test('initializes form with empty data when prefilledData is null', () async {
+        addBookBloc.add(const InitializeForm(null));
+        await Future.delayed(Duration.zero);
+
+        expect(addBookBloc.state.title, '');
+        expect(addBookBloc.state.author, '');
+        expect(addBookBloc.state.isFavorite, false);
+      });
+    });
+
+    group('UpdateFormField', () {
+      test('updates title field', () async {
+        addBookBloc.add(const UpdateFormField('title', 'New Title'));
+        await Future.delayed(Duration.zero);
+
+        expect(addBookBloc.state.title, 'New Title');
+      });
+
+      test('updates author field', () async {
+        addBookBloc.add(const UpdateFormField('author', 'New Author'));
+        await Future.delayed(Duration.zero);
+
+        expect(addBookBloc.state.author, 'New Author');
+      });
+
+      test('updates genre field', () async {
+        addBookBloc.add(const UpdateFormField('genre', 'New Genre'));
+        await Future.delayed(Duration.zero);
+
+        expect(addBookBloc.state.genre, 'New Genre');
+      });
+
+      test('updates pages field', () async {
+        addBookBloc.add(const UpdateFormField('pages', 300));
+        await Future.delayed(Duration.zero);
+
+        expect(addBookBloc.state.pages, 300);
+      });
+
+      test('updates rating field', () async {
+        addBookBloc.add(const UpdateFormField('rating', 4.8));
+        await Future.delayed(Duration.zero);
+
+        expect(addBookBloc.state.rating, 4.8);
+      });
+
+      test('updates status field', () async {
+        addBookBloc.add(const UpdateFormField('status', BookStatus.done));
+        await Future.delayed(Duration.zero);
+
+        expect(addBookBloc.state.status, BookStatus.done);
+      });
+    });
+
+    group('ToggleFavorite', () {
+      test('toggles isFavorite from false to true', () async {
+        expect(addBookBloc.state.isFavorite, false);
+
+        addBookBloc.add(const ToggleFavorite());
+        await Future.delayed(Duration.zero);
+
+        expect(addBookBloc.state.isFavorite, true);
+      });
+
+      test('toggles isFavorite from true to false', () async {
+        addBookBloc.add(const ToggleFavorite());
+        await Future.delayed(Duration.zero);
+        expect(addBookBloc.state.isFavorite, true);
+
+        addBookBloc.add(const ToggleFavorite());
+        await Future.delayed(Duration.zero);
+
+        expect(addBookBloc.state.isFavorite, false);
+      });
+    });
+
+    group('ClearForm', () {
+      test('clears all form fields', () async {
+        addBookBloc.add(const UpdateFormField('title', 'Test'));
+        addBookBloc.add(const UpdateFormField('author', 'Test'));
+        addBookBloc.add(const ToggleFavorite());
+        await Future.delayed(Duration.zero);
+
+        expect(addBookBloc.state.title, 'Test');
+
+        addBookBloc.add(const ClearForm());
+        await Future.delayed(Duration.zero);
+
+        expect(addBookBloc.state.title, '');
+        expect(addBookBloc.state.author, '');
+        expect(addBookBloc.state.isFavorite, false);
+      });
+    });
+
+    group('SubmitBook', () {
+      test('creates book with form data and sets isSubmitted to true', () async {
+        addBookBloc.add(const UpdateFormField('title', 'New Book'));
+        addBookBloc.add(const UpdateFormField('author', 'New Author'));
+        addBookBloc.add(const UpdateFormField('genre', 'New Genre'));
+        addBookBloc.add(const UpdateFormField('annotation', 'New annotation'));
+        addBookBloc.add(const UpdateFormField('pages', 200));
+        addBookBloc.add(const UpdateFormField('language', 'English'));
+        addBookBloc.add(const UpdateFormField('publishedYear', 2023));
+        addBookBloc.add(const UpdateFormField('rating', 4.5));
+        addBookBloc.add(const UpdateFormField('status', BookStatus.wantToRead));
+        addBookBloc.add(const UpdateFormField('progress', 0));
+        await Future.delayed(Duration.zero);
+
+        addBookBloc.add(const SubmitBook());
+        await Future.delayed(Duration.zero);
+
+        expect(addBookBloc.state.isSubmitted, true);
+        expect(addBookBloc.state.submittedBook?.title, 'New Book');
+        expect(addBookBloc.state.submittedBook?.author, 'New Author');
+      });
+
+      test('uses default values for empty fields', () async {
+        addBookBloc.add(const SubmitBook());
+        await Future.delayed(Duration.zero);
+
+        expect(addBookBloc.state.submittedBook?.title, 'Unknown');
+        expect(addBookBloc.state.submittedBook?.author, 'Unknown');
+        expect(addBookBloc.state.submittedBook?.genre, 'Unknown');
+        expect(addBookBloc.state.submittedBook?.coverUrl?.isNotEmpty, true);
+      });
+    });
+  });
+}