import { CommonModule } from '@angular/common';
import { APP_INITIALIZER, ModuleWithProviders, NgModule } from '@angular/core';
import { OAuthModule, OAuthStorage } from 'angular-oauth2-oidc';
import { switchMap } from 'rxjs/operators';
import { ConfigInitializerService } from '../../config/config-initializer/config-initializer.service';
import { provideDefaultConfig } from '../../config/config-providers';
import { provideConfigValidator } from '../../config/config-validator/config-validator';
import { baseUrlConfigValidator } from './config/base-url-config-validator';
import { defaultAuthConfig } from './config/default-auth-config';
import { UserAuthEventModule } from './events/user-auth-event.module';
import { AuthService } from './facade/auth.service';
import { interceptors } from './http-interceptors/index';
import { AuthStatePersistenceService } from './services/auth-state-persistence.service';
import { AuthStorageService } from './services/auth-storage.service';

/**
 * Initialize the check for `token` or `code` in the url returned from the OAuth server.
 */
export function checkOAuthParamsInUrl(
  authService: AuthService,
  configInit: ConfigInitializerService
): () => Promise<void> {
  const result = () =>
    configInit
      .getStable()
      .pipe(
        switchMap(() =>
          // Wait for stable config is used, because with auth redirect would kick so quickly that the page would not be loaded correctly
          authService.checkOAuthParamsInUrl()
        )
      )
      .toPromise();

  return result;
}

export function authStatePersistenceFactory(
  authStatePersistenceService: AuthStatePersistenceService
) {
  const result = () => authStatePersistenceService.initSync();
  return result;
}

/**
 * Authentication module for a user. Handlers requests for logged in users,
 * provides authorization services and storage for tokens.
 */
@NgModule({
  imports: [CommonModule, OAuthModule.forRoot(), UserAuthEventModule],
})
export class UserAuthModule {
  static forRoot(): ModuleWithProviders<UserAuthModule> {
    return {
      ngModule: UserAuthModule,
      providers: [
        provideDefaultConfig(defaultAuthConfig),
        provideConfigValidator(baseUrlConfigValidator),
        ...interceptors,
        {
          provide: OAuthStorage,
          useExisting: AuthStorageService,
        },
        {
          provide: APP_INITIALIZER,
          useFactory: authStatePersistenceFactory,
          deps: [AuthStatePersistenceService],
          multi: true,
        },
        {
          provide: APP_INITIALIZER,
          useFactory: checkOAuthParamsInUrl,
          deps: [AuthService, ConfigInitializerService],
          multi: true,
        },
      ],
    };
  }
}