/**
 * @license
 * Copyright Google LLC All Rights Reserved.
 *
 * Use of this source code is governed by an MIT-style license that can be
 * found in the LICENSE file at https://angular.io/license
 */

import {Component, destroyPlatform, ErrorHandler, Inject, Injectable, InjectionToken, NgModule, NgZone, PlatformRef} from '@angular/core';
import {R3Injector} from '@angular/core/src/di/r3_injector';
import {NoopNgZone} from '@angular/core/src/zone/ng_zone';
import {withBody} from '@angular/private/testing';

import {bootstrapApplication, BrowserModule} from '../../src/browser';

describe('bootstrapApplication for standalone components', () => {
  beforeEach(destroyPlatform);
  afterEach(destroyPlatform);

  class SilentErrorHandler extends ErrorHandler {
    override handleError() {
      // the error is already re-thrown by the application ref.
      // we don't want to print it, but instead catch it in tests.
    }
  }

  it('should create injector where ambient providers shadow explicit providers',
     withBody('<test-app></test-app>', async () => {
       const testToken = new InjectionToken('test token');

       @NgModule({
         providers: [
           {provide: testToken, useValue: 'Ambient'},
         ]
       })
       class AmbientModule {
       }

       @Component({
         selector: 'test-app',
         standalone: true,
         template: `({{testToken}})`,
         imports: [AmbientModule]
       })
       class StandaloneCmp {
         constructor(@Inject(testToken) readonly testToken: String) {}
       }

       const appRef = await bootstrapApplication(StandaloneCmp, {
         providers: [
           {provide: testToken, useValue: 'Bootstrap'},
         ]
       });

       appRef.tick();

       // make sure that ambient providers "shadow" ones explicitly provided during bootstrap
       expect(document.body.textContent).toBe('(Ambient)');
     }));

  it('should be able to provide a custom zone implementation in DI',
     withBody('<test-app></test-app>', async () => {
       @Component({
         selector: 'test-app',
         standalone: true,
         template: ``,
       })
       class StandaloneCmp {
       }

       class CustomZone extends NoopNgZone {}
       const instance = new CustomZone();

       const appRef = await bootstrapApplication(
           StandaloneCmp, {providers: [{provide: NgZone, useValue: instance}]});

       appRef.tick();
       expect(appRef.injector.get(NgZone)).toEqual(instance);
     }));

  /*
    This test verifies that ambient providers for the standalone component being bootstrapped
    (providers collected from the import graph of a standalone component) are instantiated in a
    dedicated standalone injector. As the result we are ending up with the following injectors
    hierarchy:
    - platform injector (platform specific providers go here);
    - application injector (providers specified in the bootstrap options go here);
    - standalone injector (ambient providers go here);
  */
  it('should create a standalone injector for standalone components with ambient providers',
     withBody('<test-app></test-app>', async () => {
       const ambientToken = new InjectionToken('ambient token');

       @NgModule({
         providers: [
           {provide: ambientToken, useValue: 'Only in AmbientNgModule'},
         ]
       })
       class AmbientModule {
       }

       @Injectable()
       class NeedsAmbientProvider {
         constructor(@Inject(ambientToken) readonly ambientToken: String) {}
       }

       @Component({
         selector: 'test-app',
         template: `({{service.ambientToken}})`,
         standalone: true,
         imports: [AmbientModule]
       })
       class StandaloneCmp {
         constructor(readonly service: NeedsAmbientProvider) {}
       }

       try {
         await bootstrapApplication(
             StandaloneCmp,
             {
               providers: [
                 {provide: ErrorHandler, useClass: SilentErrorHandler},
                 NeedsAmbientProvider,
               ]
             },
         );

         // we expect the bootstrap process to fail since the "NeedsAmbientProvider" service
         // (located in the application injector) can't "see" ambient providers (located in a
         // standalone injector that is a child of the application injector).
         fail('Expected to throw');
       } catch (e: unknown) {
         expect(e).toBeInstanceOf(Error);
         expect((e as Error).message).toContain('No provider for InjectionToken ambient token!');
       }
     }));

  it('should throw if `BrowserModule` is imported in the standalone bootstrap scenario',
     withBody('<test-app></test-app>', async () => {
       @Component({
         selector: 'test-app',
         template: '...',
         standalone: true,
         imports: [BrowserModule],
       })
       class StandaloneCmp {
       }

       try {
         await bootstrapApplication(
             StandaloneCmp, {providers: [{provide: ErrorHandler, useClass: SilentErrorHandler}]});

         // The `bootstrapApplication` already includes the set of providers from the
         // `BrowserModule`, so including the `BrowserModule` again will bring duplicate providers
         // and we want to avoid it.
         fail('Expected to throw');
       } catch (e: unknown) {
         expect(e).toBeInstanceOf(Error);
         expect((e as Error).message)
             .toContain('NG05100: Providers from the `BrowserModule` have already been loaded.');
       }
     }));

  it('should throw if `BrowserModule` is imported indirectly in the standalone bootstrap scenario',
     withBody('<test-app></test-app>', async () => {
       @NgModule({
         imports: [BrowserModule],
       })
       class SomeDependencyModule {
       }

       @Component({
         selector: 'test-app',
         template: '...',
         standalone: true,
         imports: [SomeDependencyModule],
       })
       class StandaloneCmp {
       }

       try {
         await bootstrapApplication(
             StandaloneCmp, {providers: [{provide: ErrorHandler, useClass: SilentErrorHandler}]});

         // The `bootstrapApplication` already includes the set of providers from the
         // `BrowserModule`, so including the `BrowserModule` again will bring duplicate providers
         // and we want to avoid it.
         fail('Expected to throw');
       } catch (e: unknown) {
         expect(e).toBeInstanceOf(Error);
         expect((e as Error).message)
             .toContain('NG05100: Providers from the `BrowserModule` have already been loaded.');
       }
     }));

  it('should trigger an app destroy when a platform is destroyed',
     withBody('<test-app></test-app>', async () => {
       let compOnDestroyCalled = false;
       let serviceOnDestroyCalled = false;
       let injectorOnDestroyCalled = false;

       @Injectable({providedIn: 'root'})
       class ServiceWithOnDestroy {
         ngOnDestroy() {
           serviceOnDestroyCalled = true;
         }
       }

       @Component({
         selector: 'test-app',
         standalone: true,
         template: 'Hello',
       })
       class ComponentWithOnDestroy {
         constructor(service: ServiceWithOnDestroy) {}

         ngOnDestroy() {
           compOnDestroyCalled = true;
         }
       }

       const appRef = await bootstrapApplication(ComponentWithOnDestroy);
       const injector = (appRef as unknown as {injector: R3Injector}).injector;
       injector.onDestroy(() => injectorOnDestroyCalled = true);

       expect(document.body.textContent).toBe('Hello');

       const platformRef = injector.get(PlatformRef);
       platformRef.destroy();

       // Verify the callbacks were invoked.
       expect(compOnDestroyCalled).toBe(true);
       expect(serviceOnDestroyCalled).toBe(true);
       expect(injectorOnDestroyCalled).toBe(true);

       // Make sure the DOM has been cleaned up as well.
       expect(document.body.textContent).toBe('');
     }));
});