auth.effects.ts

import { Injectable } from '@angular/core';
import { Router } from '@angular/router';
import { Actions, createEffect, ofType } from '@ngrx/effects';
import { Store } from '@ngrx/store';
import { of } from 'rxjs';
import {
  catchError,
  concatMap,
  distinctUntilChanged,
  exhaustMap,
  map,
  switchMap,
  tap,
} from 'rxjs/operators';
import { UserService } from 'src/app/user/services/user.service';
import { AuthService } from '../../auth/services/auth.service';
import {
  fetchAuthenticatedUserDataFailure,
  fetchAuthenticatedUserDataSuccess,
  removeUserToken,
  saveUserToken,
  saveUserTokenFailure,
  saveUserTokenSuccess,
  signInUser,
  signOutUser,
  userTokenExists,
} from './auth.actions';
import { selectAuthUserName } from './auth.selectors';
import { userApiToAuthUserData } from './auth.mappings';

@Injectable()
export class AuthEffects {
  /**
   * Start the OAuth sign in process for the user - does not dispatch
   * since it does not need to return a new action
   */
  signIn$ = createEffect(
    () =>
      this.actions$.pipe(
        ofType(signInUser),
        tap(() => this.authService.signIn()),
      ),
    { dispatch: false },
  );

  /**
   *   Start the sign out process for the user
   */
  signOut$ = createEffect(() => {
    return this.actions$.pipe(
      ofType(signOutUser),
      tap(() => this.authService.signOut()),
      tap(() => this.router.navigate(['/signin'])),
      switchMap(() => of(removeUserToken({ isAuthenticated: false }))),
    );
  });

  /**
   * Saves the resulting access_token for the user
   */
  saveUserToken$ = createEffect(() => {
    return this.actions$.pipe(
      ofType(saveUserToken),
      concatMap(() =>
        this.authService.saveUserToken().pipe(
          map(() => saveUserTokenSuccess({ isAuthenticated: true })),
          catchError((error) => of(saveUserTokenFailure({ error }))),
        ),
      ),
    );
  });

  /**
   * Gets authenticated user's name, photo, and email
   */
  fetchAuthUserData$ = createEffect(() => {
    return this.actions$.pipe(
      ofType(saveUserTokenSuccess, userTokenExists),
      switchMap(() =>
        this.store.select(selectAuthUserName).pipe(
          distinctUntilChanged(),
          exhaustMap(() =>
            this.userService.getAuthenticatedUserInfo().pipe(
              map((apiResponse) => {
                const userData = userApiToAuthUserData(apiResponse);
                return fetchAuthenticatedUserDataSuccess({ userData });
              }),
              catchError((error) =>
                of(fetchAuthenticatedUserDataFailure({ error })),
              ),
            ),
          ),
        ),
      ),
    );
  });

  constructor(
    private actions$: Actions,
    private store: Store,
    private authService: AuthService,
    private userService: UserService,
    private router: Router,
  ) {}
}