Takumon/mean-blog

import { Injectable } from '@angular/core';
import { HttpClient } from '@angular/common/http';
import { Observable, throwError } from 'rxjs';
import { map, catchError } from 'rxjs/operators';

import {
  UserModel,
  CudSuccessModel
} from '../models';
import { LocalStorageService, LOCALSTORAGE_KEY } from './local-storage.service';

export interface LoginSuccessInfo {
  success: boolean;
  message: string;
  token?: string;
  user?: UserModel;
}

export interface CheckStateInfo extends LoginSuccessInfo {
  error?: string;
}


/**
 * 認証操作を行い、ユーザ情報と認証トークンを保持する
 */
@Injectable()
export class AuthenticationService {
  loginUser: UserModel;
  isFinishedCheckState = false;

  private base_url = '/api/authenticate';

  constructor(
    private http: HttpClient,
    private localStorageService: LocalStorageService,
  ) {
  }


  login(user: {
      userId: string,
      password: string
    }): Observable<LoginSuccessInfo> {
    const URL = `${this.base_url}/login`;

    return this.http
      .post<LoginSuccessInfo>(URL, user)
      .pipe(
        map((res: LoginSuccessInfo) => this.setToken(res))
      );
  }


  register(user: {
    userId: string,
    password: string,
    confirmPassword: string,
  }): Observable<LoginSuccessInfo> {
    const URL = `${this.base_url}/register`;

    return this.http
      .post<Object>(URL, user)
      .pipe(map((res: LoginSuccessInfo) => this.setToken(res) ));
  }

  changePassword(passwordInfo: {
    oldPassword: string,
    newPassword: string,
    newConfirmPassword: string
  }): Observable<CudSuccessModel<UserModel>> {

    const URL = `${this.base_url}/changepassword`;

    passwordInfo['_id'] = this.loginUser._id;

    return this.http
      .put<CudSuccessModel<UserModel>>(URL, passwordInfo)
      .pipe(
        map(res => {
          // tokenはパスワードに依存しないのでユーザ情報だけを更新する
          this.loginUser = res.obj;
          return res;
        })
      );
  }

  checkState(): Observable<CheckStateInfo> {
    const URL = `${this.base_url}/check-state`;

    return this.http
      .get<CheckStateInfo>(URL)
      .pipe(
        map(res => this.setToken(res)),
        catchError(res => {
          this.isFinishedCheckState = true;
          return throwError(res);
        })
      );
  }


  // ログイン画面に戻る時に使用する
  logout() {
    this.loginUser = null;
    this.localStorageService.remove(LOCALSTORAGE_KEY.TOKEN);
  }


  private setToken(res: LoginSuccessInfo): LoginSuccessInfo {
    if ( res.success !== true ) {
      this.isFinishedCheckState = true;
      return res;
    }

    this.localStorageService.set(LOCALSTORAGE_KEY.TOKEN, res.token);
    this.loginUser = res.user;
    this.isFinishedCheckState = true;

    return res;
  }

  isLogin(): boolean {
    return !!this.loginUser;
  }

  isAdmin(): boolean {
    return this.isLogin() && this.loginUser.isAdmin;
  }

  getToken(): String {
    return this.localStorageService.get(LOCALSTORAGE_KEY.TOKEN);
  }

  hasToken(): boolean {
    return this.localStorageService.has(LOCALSTORAGE_KEY.TOKEN);
  }
}