import { async, TestBed, ComponentFixture } from '@angular/core/testing';
import { Component, DebugElement } from '@angular/core';
import { By } from '@angular/platform-browser';

import { DraggableDirective } from '.';

@Component({
  selector: 'test-fixture-component',
  template: `
    <div draggable></div>
  `
})
class TestFixtureComponent {
}

describe('DraggableDirective', () => {
  let fixture: ComponentFixture<TestFixtureComponent>;
  let component: TestFixtureComponent;
  let element: any;

  // provide our implementations or mocks to the dependency injector
  beforeEach(() => {
    TestBed.configureTestingModule({
      declarations: [ 
        DraggableDirective,
        TestFixtureComponent
      ]
    });
  });

  beforeEach(async(() => {
    TestBed.compileComponents().then(() => {
      fixture = TestBed.createComponent(TestFixtureComponent);
      component = fixture.componentInstance;
      element = fixture.nativeElement;
    });
  }));

  describe('fixture', () => {
    let directive: DraggableDirective;
    
    beforeEach(() => {
      directive = fixture.debugElement
        .query(By.directive(DraggableDirective))
        .injector.get(DraggableDirective);
    });

    it('should have a component instance', () => {
      expect(component).toBeTruthy();
    });

    it('should have DraggableDirective directive', () => {
      expect(directive).toBeTruthy();
    });

    describe('mouse event', () => {
      let mouseDown: MouseEvent;

      beforeEach(() => {
        element.classList.add('draggable');
        mouseDown = <MouseEvent>{
          target: element,
          // tslint:disable-next-line
          preventDefault: () => {}
        };
      });

      // or else the document:mouseup event can fire again when resizing.
      describe('subscription should be destroyed', () => {

        it('when ngOnDestroy is called', () => {
          directive.onMousedown(mouseDown);
          expect(directive.subscription).toBeTruthy();

          directive.ngOnDestroy();

          expect(directive.subscription).toBeUndefined();
        });

        it('when onMouseup called and dragging', () => {
          directive.onMousedown(mouseDown);
          expect(directive.subscription).toBeTruthy();

          directive.onMouseup(<MouseEvent>{ });

          expect(directive.subscription).toBeUndefined();
        });
      });

      describe('subscription should not be destroyed', () => {

        it('when onMouseup is called and not dragging', () => {
          directive.onMousedown(mouseDown);
          directive.isDragging = false;

          expect(directive.subscription).toBeTruthy();

          directive.onMouseup(<MouseEvent>{ });

          expect(directive.subscription).toBeTruthy();
        });
      });
    });
  });
});