import 'package:dart_di/di_container.dart';
import 'package:dart_di/resolvers/resolver.dart';
import 'package:test/test.dart';
import 'package:mockito/mockito.dart';

void main() {
  group('Without parent', () {
    test('Container bind<T> throws state error if it\'s already has resolver',
        () {
      final container = new DiContainer();
      container.bind<int>().toResolver(_makeResolver(5));

      expect(() => container.bind<int>().toResolver(_makeResolver(3)),
          throwsA(isA<StateError>()));
    });

    test("Container resolves value after adding a dependency", () {
      final expectedValue = 3;
      final container = new DiContainer();
      container.bind<int>().toResolver(_makeResolver(expectedValue));
      expect(container.resolve<int>(), expectedValue);
    });

    test("Container throws state error if the value can't be resolved", () {
      final container = DiContainer();
      expect(() => container.resolve<int>(), throwsA(isA<StateError>()));
    });

    test("Container has() returns true if it has resolver", () {
      final expectedValue = 5;
      final container = new DiContainer();
      container.bind<int>().toResolver(_makeResolver(expectedValue));
      expect(container.has<int>(), true);
    });

    test("Container has() returns false if it hasn't resolver", () {
      final container = new DiContainer();
      expect(container.has<int>(), false);
    });

    test("Container hasInTree() returns true if it has resolver", () {
      final expectedValue = 5;
      final container = DiContainer();
      container.bind<int>().toResolver(_makeResolver(expectedValue));
      expect(container.hasInTree<int>(), true);
    });

    test("Container hasInTree() returns true if it hasn`t resolver", () {
      final container = DiContainer();
      expect(container.hasInTree<int>(), false);
    });
  });

  group('With parent', () {
    test(
        "Container bind() throws state error (if it's parent already has a resolver)",
        () {
      final parentContainer = new DiContainer();
      final container = new DiContainer(parentContainer);

      parentContainer.bind<int>().toResolver(_makeResolver(5));

      expect(() => container.bind<int>().toResolver(_makeResolver(3)),
          throwsA(isA<StateError>()));
    });

    test("Container resolve() returns a value from parent container", () {
      final expectedValue = 5;
      final parentContainer = DiContainer();
      final container = DiContainer(parentContainer);

      parentContainer.bind<int>().toResolver(_makeResolver(expectedValue));

      expect(container.resolve<int>(), expectedValue);
    });
  });

  test("Container resolve() returns a  several value from parent container",
      () {
    final expectedIntValue = 5;
    final expectedStringValue = "Hello world";
    final parentContainer = DiContainer();
    final container = DiContainer(parentContainer);

    parentContainer.bind<int>().toResolver(_makeResolver(expectedIntValue));
    parentContainer
        .bind<String>()
        .toResolver(_makeResolver(expectedStringValue));

    expect(container.resolve<int>(), expectedIntValue);
    expect(container.resolve<String>(), expectedStringValue);
  });

  test("Container resolve() throws a state error if parent hasn't value too",
      () {
    final parentContainer = DiContainer();
    final container = DiContainer(parentContainer);
    expect(() => container.resolve<int>(), throwsA(isA<StateError>()));
  });

  test("Container has() returns false if parent has a resolver", () {
    final parentContainer = DiContainer();
    final container = DiContainer(parentContainer);

    parentContainer.bind<int>().toResolver(_makeResolver(5));

    expect(container.has<int>(), false);
  });

  test("Container has() returns false if parent hasn't a resolver", () {
    final parentContainer = DiContainer();
    final container = DiContainer(parentContainer);

    expect(container.has<int>(), false);
  });

  test("Container hasInTree() returns true if parent has a resolver", () {
    final parentContainer = DiContainer();
    final container = DiContainer(parentContainer);

    parentContainer.bind<int>().toResolver(_makeResolver(5));

    expect(container.hasInTree<int>(), true);
  });

  test("Test asSingelton", () {
    final expectedIntValue = 10;
    final containerA = DiContainer();
    final containerB = DiContainer(containerA);

    containerA.bind<int>().toValue(expectedIntValue).asSingleton();

    expect(containerB.resolve<int>(), expectedIntValue);
  });

  test("Bind to the factory resolves with value", () {
    final container = DiContainer();
    final b = B();
    container.bind<A>().toFactory(() => b);

    expect(container.resolve<A>(), b);
  });
}

ResolverMock<T> _makeResolver<T>(T expectedValue) {
  final resolverMock = new ResolverMock<T>();
  when(resolverMock.resolve()).thenReturn(expectedValue);
  return resolverMock;
}

class ResolverMock<T> extends Mock implements Resolver<T> {}

abstract class A {}

class B implements A {}

class DependOnA {
  final A a;

  DependOnA(this.a) : assert(a != null);
}