Adds bloc implementation

lib/core/utils/string_constants.dart

@@ -0,0 +1 @@
+const String serverErrorMessage = "Server error, please try agian later!";

lib/features/home/presentation/bloc/unsplash_image_bloc.dart

@@ -0,0 +1,27 @@
+import 'package:bloc/bloc.dart';
+import 'package:equatable/equatable.dart';
+import 'package:unplash_sample/core/utils/string_constants.dart';
+import 'package:unplash_sample/features/home/domain/entities/image.dart';
+import 'package:unplash_sample/features/home/domain/usecases/fetch_images.dart';
+
+part 'unsplash_image_event.dart';
+part 'unsplash_image_state.dart';
+
+class UnsplashImageBloc extends Bloc<UnsplashImageEvent, UnsplashImageState> {
+  final FetchImages fetchImages;
+
+  UnsplashImageBloc(this.fetchImages) : super(UnsplashImageInitialState()) {
+    on<UnsplashImageEvent>((event, emit) async {
+      if (event is FetchImageEvent) {
+        emit(UnsplashImageLoadingState());
+
+        final imagesEither = await fetchImages(event.params);
+        imagesEither.fold((error) {
+          emit(const UnsplashImageErrorState(serverErrorMessage));
+        }, (images) {
+          emit(UnsplashImageLoadedState(images));
+        });
+      }
+    });
+  }
+}

lib/features/home/presentation/bloc/unsplash_image_event.dart

@@ -0,0 +1,17 @@
+part of 'unsplash_image_bloc.dart';
+
+abstract class UnsplashImageEvent extends Equatable {
+  const UnsplashImageEvent();
+
+  @override
+  List<Object> get props => [];
+}
+
+class FetchImageEvent extends UnsplashImageEvent {
+  final FetchImageParams params;
+
+  const FetchImageEvent(this.params);
+
+  @override
+  List<Object> get props => [params.page, params.perPage];
+}

lib/features/home/presentation/bloc/unsplash_image_state.dart

@@ -0,0 +1,30 @@
+part of 'unsplash_image_bloc.dart';
+
+abstract class UnsplashImageState extends Equatable {
+  const UnsplashImageState();
+
+  @override
+  List<Object> get props => [];
+}
+
+class UnsplashImageInitialState extends UnsplashImageState {}
+
+class UnsplashImageLoadingState extends UnsplashImageState {}
+
+class UnsplashImageLoadedState extends UnsplashImageState {
+  final List<UnsplashImage> images;
+
+  const UnsplashImageLoadedState(this.images);
+
+  @override
+  List<Object> get props => [images];
+}
+
+class UnsplashImageErrorState extends UnsplashImageState {
+  final String errorMessage;
+
+  const UnsplashImageErrorState(this.errorMessage);
+
+  @override
+  List<Object> get props => [errorMessage];
+}

pubspec.lock

@@ -33,6 +33,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "2.11.0"
+  bloc:
+    dependency: "direct main"
+    description:
+      name: bloc
+      sha256: "3820f15f502372d979121de1f6b97bfcf1630ebff8fe1d52fb2b0bfa49be5b49"
+      url: "https://pub.dev"
+    source: hosted
+    version: "8.1.2"
   boolean_selector:
     dependency: transitive
     description:

pubspec.yaml

@@ -30,6 +30,7 @@ environment:
 dependencies:
   flutter:
     sdk: flutter
+  bloc: ^8.1.2
   dartz: ^0.10.1
   dio: ^5.3.0
   equatable: ^2.0.5

test/core/mocks/fetch_images_mock.dart

@@ -0,0 +1,6 @@
+import 'package:mocktail/mocktail.dart';
+import 'package:unplash_sample/features/home/domain/usecases/fetch_images.dart';
+
+class FetchImagesMock extends Mock implements FetchImages {}
+
+class FakeFetchImageParams extends Fake implements FetchImageParams {}

test/features/home/presentation/bloc/unsplash_image_bloc_test.dart

@@ -0,0 +1,77 @@
+import 'dart:convert';
+
+import 'package:bloc/bloc.dart';
+import 'package:dartz/dartz.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:mocktail/mocktail.dart';
+import 'package:unplash_sample/core/error/error.dart';
+import 'package:unplash_sample/core/utils/string_constants.dart';
+import 'package:unplash_sample/features/home/data/models/image_model.dart';
+import 'package:unplash_sample/features/home/domain/usecases/fetch_images.dart';
+import 'package:unplash_sample/features/home/presentation/bloc/unsplash_image_bloc.dart';
+
+import '../../../../core/mocks/fetch_images_mock.dart';
+import '../../../../fixtures/fixture_reader.dart';
+
+void main() {
+  late final FetchImagesMock fetchImagesMock;
+  late final Bloc bloc;
+  late final FetchImageParams params;
+
+  group("UnsplashImageBloc test", () {
+    setUpAll(() {
+      fetchImagesMock = FetchImagesMock();
+      bloc = UnsplashImageBloc(fetchImagesMock);
+      params = FetchImageParams(1, 20);
+
+      registerFallbackValue(FakeFetchImageParams());
+    });
+
+    test("Initial state should be UnsplashImageInitialState", () {
+      expect(bloc.state, UnsplashImageInitialState());
+    });
+
+    test(
+      "Emits [UnsplashImageLoadingState, UnsplashImageErrroState] on error",
+      () {
+        when(() => fetchImagesMock.call(any())).thenAnswer((invocation) async {
+          return Left(ServerError());
+        });
+
+        bloc.add(FetchImageEvent(params));
+
+        expectLater(
+          bloc.stream,
+          emitsInOrder([
+            UnsplashImageLoadingState(),
+            const UnsplashImageErrorState(serverErrorMessage),
+          ]),
+        );
+      },
+    );
+
+    test(
+      "Emits [UnsplashImageLoadingState, UnsplashImageLoadedState] on success",
+      () {
+        final imageListModel =
+            UnsplashImageListModel.fromJson(List<Map<String, dynamic>>.from(
+          jsonDecode(fixture("image_model_fixture.json")),
+        ));
+
+        when(() => fetchImagesMock.call(any())).thenAnswer((invocation) async {
+          return Right(imageListModel.images);
+        });
+
+        bloc.add(FetchImageEvent(params));
+
+        expectLater(
+          bloc.stream,
+          emitsInOrder([
+            UnsplashImageLoadingState(),
+            UnsplashImageLoadedState(imageListModel.images),
+          ]),
+        );
+      },
+    );
+  });
+}