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import { Injectable } from '@angular/core';
import { Router} from '@angular/router';
import { auth } from 'firebase/app';
import { AngularFireAuth } from '@angular/fire/auth';

import { User } from 'firebase';
import { LoginComponent } from '../admin/login/login.component';
import { ɵNullViewportScroller } from '@angular/common';

@Injectable({
  providedIn: 'root'
})
export class AuthService {
user: User;
  constructor(public afAuth: AngularFireAuth, public router: Router) { }
}

this.afAuth.authState.subscribe(user => {
  if (user) {
    this.user = user;
    localStorage.setItem('user', JSON.stringify(this.user));
  } else {
    localStorage.setItem('user', null);
  }
})

async login(email: string, password: string){
  try {
    await this.afAuth.auth.signInWithEmailAndPassword(email, password)
    this.router.navigate(['admin/list']);
  } catch (e) {
    alert( 'Error!' + e.message);
  }
}

async logout(){
  await this.afAuth.auth.signOut();
  localStorage.removeItem('user');
  this.router.navigate(['admin/login']);
}

get isLoggedIn(): boolean {
  const user = JSON.parse(localStorage.grtItem('user'));
  return user !== ɵNullViewportScroller;
}