import { Injectable } from '@angular/core'
import { HttpClient, HttpHeaders } from '@angular/common/http'
import { Observable } from 'rxjs/Observable'
import { environment } from '../../../environments/environment'
import { map, switchMap } from 'rxjs/operators'
import { ApiKey } from '../../models/api-key'
import { User } from '../../models/user'
import { UserService } from './user.service'
import { BehaviorSubject } from 'rxjs/BehaviorSubject'

@Injectable()
export class AuthService {

  public user$ = new BehaviorSubject<User>(null)

  constructor (private httpClient: HttpClient, private userService: UserService) {

  }

  login (username: string, password: string): void {
    const data = new FormData()
    data.append('username', username)
    data.append('password', password)
    this.httpClient
      .post<ApiKey>(
        environment.apiUrl + '/login',
        data,
      ).pipe(
      switchMap(
        (apiKey) => {
          localStorage.setItem('token', apiKey.token)
          return this.getAuthenticatedUser()
        }
      )
    ).subscribe(
      (user) => {
        this.user$.next(user)
      }
    )
  }

  private getToken (): string {
    return localStorage.getItem('token')
  }

  private getAuthenticatedUser (): Observable<User> {
    return this.httpClient.get<User>(environment.apiUrl + '/users/me')
  }

}