import { Injectable } from '@angular/core';
import { AngularFireAuth } from 'angularfire2/auth';
import { Router, CanActivate } from '@angular/router';
import { firebase } from '@firebase/app';
import { AngularFireDatabase } from 'angularfire2/database';
import { User } from '../../models/user';
import { Observable } from 'rxjs/Observable';
import { CompetitionService } from '../competitionService/competition.service';
import { UserService } from '../userService/user.service';

@Injectable()
export class AuthService implements CanActivate {
  defaultRole = 'player';

  constructor(
    public afAuth: AngularFireAuth,
    private router: Router,
    private db: AngularFireDatabase,
    private competitionService: CompetitionService,
    private userService: UserService
  ) {
  }

  get authenticated(): boolean {
    return this.userService.getLoggedInUserSource() !== null;
  }

  get currentUser(): any {
    return this.authenticated ? this.userService.getLoggedInUserSource() : null;
  }
  googleLogin() {
    const promise = new Promise((resolve, reject) => {
      const provider = new firebase.auth.GoogleAuthProvider();
      provider.addScope('profile');
      provider.addScope('email');
      firebase
        .auth()
        .signInWithPopup(provider)
        .then(result => {
          if (result.user) {
            const token = result.credential.accessToken;
            this.doesUserExist(result.user, resolve);
          } else {
            reject();
          }
        });
    });
    return promise;
  }

  doesUserExist(user, resolve) {
    this.userService.getAllUsersObservable().subscribe(dbUsers => {
      let alreadyExist = false;
      for (const dbUser of dbUsers) {
        const cast = dbUser as User;
        if (cast.uid === user.uid) {
          alreadyExist = true;
          this.userService.setLoggedInUser(cast);
        }
      }
      if (alreadyExist === false) {
        const newUser = new User(user.uid, user.displayName, this.defaultRole);
        this.db.list('/users/').push(newUser);
        this.userService.setLoggedInUser(newUser);
      }
      resolve();
    });
  }

  signOut() {
    const promise = new Promise((resolve, reject) => {
      this.afAuth.auth.signOut();
      this.userService.setLoggedInUser(null);
      this.router.navigate(['/']);
    });
    return promise;
  }

  canActivate(): boolean {
    if (this.userService.getLoggedInUserSource() == null) {
      this.router.navigate(['/']);
      return false;
    }
    return true;
  }

  isAdmin(): boolean {
    if (this.userService.getLoggedInUserSource() != null && this.userService.getLoggedInUserSource().role === 'admin') {
      return true;
    } else {
      return false;
    }
  }
}