import { ComponentFixture, TestBed } from '@angular/core/testing';
import { BehaviorSubject } from 'rxjs';

import { ApiListComponent } from './api-list.component';
import { ApiItem, ApiSection, ApiService } from './api.service';
import { LocationService } from 'app/shared/location.service';
import { Logger } from 'app/shared/logger.service';
import { MockLogger } from 'testing/logger.service';
import { ApiListModule } from './api-list.module';

describe('ApiListComponent', () => {
  let component: ApiListComponent;
  let fixture: ComponentFixture<ApiListComponent>;
  let sections: ApiSection[];

  beforeEach(() => {
    TestBed.configureTestingModule({
      imports: [ ApiListModule ],
      providers: [
        { provide: ApiService, useClass: TestApiService },
        { provide: Logger, useClass: MockLogger },
        { provide: LocationService, useClass: TestLocationService }
      ]
    });

    fixture = TestBed.createComponent(ApiListComponent);
    component = fixture.componentInstance;
    sections = getApiSections();
  });

  /**
   * Expectation Utility: Assert that filteredSections has the expected result for this test.
   *
   * @param itemTest - return true if the item passes the match test
   *
   * Subscribes to `filteredSections` and performs expectation within subscription callback.
   */
  function expectFilteredResult(label: string, itemTest: (item: ApiItem) => boolean) {
    component.filteredSections.subscribe(filtered => {
      filtered = filtered.filter(section => section.items);
      expect(filtered.length).withContext('expected something').toBeGreaterThan(0);
      expect(filtered.every(section => section.items?.every(itemTest))).withContext(label).toBe(true);
    });
  }


  describe('#filteredSections', () => {

    beforeEach(() => {
      fixture.detectChanges();
    });

    it('should return all complete sections when no criteria', () => {
      let filtered: ApiSection[]|undefined;
      component.filteredSections.subscribe(f => filtered = f);
      expect(filtered).toEqual(sections);
    });

    it('item.show should be true for all queried items', () => {
      component.setQuery('class');
      expectFilteredResult('query: class', item => /class/.test(item.name));
    });

    it('items should be an array for every item in section when query matches section name', () => {
      component.setQuery('core');
      component.filteredSections.subscribe(filtered => {
        filtered = filtered.filter(section => Array.isArray(section.items));
        expect(filtered.length).withContext('only one section').toBe(1);
        expect(filtered[0].name).toBe('core');
        expect(filtered[0].items).toEqual(sections.find(section => section.name === 'core')?.items as ApiItem[]);
      });
    });

    describe('section.items', () => {
      it('should null if there are no matching items and the section itself does not match', () => {
        component.setQuery('core');
        component.filteredSections.subscribe(filtered => {
          const commonSection = filtered.find(section => section.name === 'common');
          expect(commonSection?.items).toBe(null);
        });
      });

      it('should be visible if they have the selected stability status', () => {
        component.setStatus({value: 'stable', title: 'Stable'});
        expectFilteredResult('status: stable', item => item.stability === 'stable');
      });

      it('should be visible if they have the selected security status', () => {
        component.setStatus({value: 'security-risk', title: 'Security Risk'});
        expectFilteredResult('status: security-risk', item => item.securityRisk);
      });

      it('should be visible if they have the selected developer preview status', () => {
        component.setStatus({value: 'developer-preview', title: 'Developer Preview'});
        expectFilteredResult('status: developer-preview', item => item.developerPreview);
      });

      it('should be visible if they match the selected API type', () => {
        component.setType({value: 'class', title: 'Class'});
        expectFilteredResult('type: class', item => item.docType === 'class');
      });
    });

    it('should have no sections and no items visible when there is no match', () => {
      component.setQuery('fizbuzz');
      component.filteredSections.subscribe(filtered => {
        expect(filtered.some(section => !!section.items)).toBeFalsy();
      });
    });
  });

  describe('initial criteria from location', () => {
    let locationService: TestLocationService;

    beforeEach(() => {
      locationService = fixture.componentRef.injector.get<any>(LocationService);
    });

    function expectOneItem(name: string, section: string, type: string, stability: string) {
      fixture.detectChanges();

      component.filteredSections.subscribe(filtered => {
        filtered = filtered.filter(s => s.items);
        expect(filtered.length).withContext('sections').toBe(1);
        expect(filtered[0].name).withContext('section name').toBe(section);
        const items = filtered[0].items as ApiItem[];
        expect(items.length).withContext('items').toBe(1);

        const item = items[0];
        const badItem = 'Wrong item: ' + JSON.stringify(item, null, 2);

        expect(item.docType).withContext(badItem).toBe(type);
        expect(item.stability).withContext(badItem).toBe(stability);
        expect(item.name).withContext(badItem).toBe(name);
      });
    }

    it('should filter as expected for ?query', () => {
      locationService.query = {query: '_3'};
      expectOneItem('class_3', 'core', 'class', 'experimental');
    });

    it('should filter as expected for ?status', () => {
      locationService.query = {status: 'deprecated'};
      expectOneItem('function_1', 'core', 'function', 'deprecated');
    });

    it('should filter as expected when status is security-risk', () => {
      locationService.query = {status: 'security-risk'};
      fixture.detectChanges();
      expectFilteredResult('security-risk', item => item.securityRisk);
    });

    it('should filter as expected when status is developer-preview', () => {
      locationService.query = {status: 'developer-preview'};
      fixture.detectChanges();
      expectFilteredResult('developer-preview', item => item.developerPreview);
    });

    it('should filter as expected for ?type', () => {
      locationService.query = {type: 'pipe'};
      expectOneItem('pipe_1', 'common', 'pipe', 'stable');
    });

    it('should filter as expected for ?query&status&type', () => {
      locationService.query = {
        query: 's_1',
        status: 'experimental',
        type: 'class'
      };
      fixture.detectChanges();
      expectOneItem('class_1', 'common', 'class', 'experimental');
    });

    it('should ignore case for ?query&status&type', () => {
      locationService.query = {
        query: 'S_1',
        status: 'ExperiMental',
        type: 'CLASS'
      };
      fixture.detectChanges();
      expectOneItem('class_1', 'common', 'class', 'experimental');
    });
  });

  describe('location path after criteria change', () => {
    let locationService: TestLocationService;

    beforeEach(() => {
      locationService = fixture.componentRef.injector.get<any>(LocationService);
    });

    it('should have query', () => {
      component.setQuery('foo');

      // `setSearch` 2nd param is a query/search params object
      const search = locationService.setSearch.calls.mostRecent().args[1];
      expect(search.query).toBe('foo');
    });

    it('should keep last of multiple query settings (in lowercase)', () => {
      component.setQuery('foo');
      component.setQuery('fooBar');

      const search = locationService.setSearch.calls.mostRecent().args[1];
      expect(search.query).toBe('foobar');
    });

    it('should have query, status, and type', () => {
      component.setQuery('foo');
      component.setStatus({value: 'stable', title: 'Stable'});
      component.setType({value: 'class', title: 'Class'});

      const search = locationService.setSearch.calls.mostRecent().args[1];
      expect(search.query).toBe('foo');
      expect(search.status).toBe('stable');
      expect(search.type).toBe('class');
    });
  });
});

////// Helpers ////////

class TestLocationService {
  query: {[index: string]: string } = {};
  setSearch = jasmine.createSpy('setSearch');
  search() { return this.query; }
}

class TestApiService {
  sectionsSubject = new BehaviorSubject(getApiSections());
  sections = this.sectionsSubject.asObservable();
}

const apiSections: ApiSection[] = [
  {
    name: 'common',
    title: 'common',
    path: 'api/common',
    deprecated: false,
    items: [
      {
        name: 'class_1',
        title: 'Class 1',
        path: 'api/common/class_1',
        docType: 'class',
        stability: 'experimental',
        securityRisk: false,
        developerPreview: false
      },
      {
        name: 'class_2',
        title: 'Class 2',
        path: 'api/common/class_2',
        docType: 'class',
        stability: 'stable',
        securityRisk: false,
        developerPreview: false
      },
      {
        name: 'directive_1',
        title: 'Directive 1',
        path: 'api/common/directive_1',
        docType: 'directive',
        stability: 'stable',
        securityRisk: true,
        developerPreview: false
      },
      {
        name: 'pipe_1',
        title: 'Pipe 1',
        path: 'api/common/pipe_1',
        docType: 'pipe',
        stability: 'stable',
        securityRisk: true,
        developerPreview: false
      },
    ],
  },
  {
    name: 'core',
    title: 'core',
    path: 'api/core',
    deprecated: false,
    items: [
      {
        name: 'class_3',
        title: 'Class 3',
        path: 'api/core/class_3',
        docType: 'class',
        stability: 'experimental',
        securityRisk: false,
        developerPreview: false
      },
      {
        name: 'function_1',
        title: 'Function 1',
        path: 'api/core/function 1',
        docType: 'function',
        stability: 'deprecated',
        securityRisk: true,
        developerPreview: false
      },
      {
        name: 'const_1',
        title: 'Const 1',
        path: 'api/core/const_1',
        docType: 'const',
        stability: 'stable',
        securityRisk: false,
        developerPreview: true
      },
    ],
  },
];

function getApiSections() { return apiSections; }