import {Component, OnInit} from '@angular/core';
import {HttpClient} from '@angular/common/http';
import {ActivatedRoute, Router} from '@angular/router';
import {AuthService} from '../../services/auth.service';
import {environment} from '../../../environments/environment';
import {SnackbarService} from '../../services/snackbar.service';

@Component({
  selector: 'app-login',
  templateUrl: './login.component.html',
  styleUrls: ['./login.component.css']
})
export class LoginComponent implements OnInit {

  openid_endpoint = environment.openid_endpoint;
  id_token;
  state;
  parsedToken;

  constructor(private http: HttpClient,
              private router: Router,
              private activatedRoute: ActivatedRoute,
              private authService: AuthService,
              private snackbar: SnackbarService) {
  }

  ngOnInit(): void {
    this.activatedRoute.fragment.subscribe(data => {
      if (data) {
        data.split('&').forEach(
          element => {
            const split = element.split('=');
            if (split[0] === 'error') {
              this.snackbar.show(split[1], 'Schließen', 5000);
              return;
            }
            if (split[0] === 'id_token') {
              this.id_token = split[1];
              this.parsedToken = JSON.parse(atob(this.id_token.split('.')[1]));
              const nonce = sessionStorage.getItem('nonce');
              if (nonce && nonce === this.parsedToken.nonce) {
                this.authService.setToken(this.id_token);
              } else {
                this.snackbar.show('Fehler bei der Anmeldung', 'Schließen', 5000);
              }
            } else if (split[0] === 'state') {
              this.state = split[1];
            }
          }
        );
      }
      if (this.authService.isAuthenticated()) {
        this.router.navigate(['tweets']);
      }
    });
  }

  login() {
    const nonce = this.randomString(20);
    sessionStorage.setItem('nonce', nonce);
    const url = this.openid_endpoint + '/auth?' +
      'client_id=waecm' +
      '&response_type=id_token' +
      '&prompt=consent' +
      '&redirect_uri=http://' + environment.location + ':' + environment.port_fe +
      '&scope=openid%20profile' +
      '&nonce=' + nonce;
    window.location.replace(url);
  }

  randomString(length: number) {
    let text = '';
    const possible = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
    for (let i = 0; i < length; i++) {
      text += possible.charAt(Math.floor(Math.random() * possible.length));
    }
    return text;
  }
}