Takumon/mean-blog

import { Injectable } from '@angular/core';
import { Router, CanActivate, ActivatedRouteSnapshot, RouterStateSnapshot } from '@angular/router';
import { Observable, of } from 'rxjs';
import { map, catchError } from 'rxjs/operators';


import {
  AuthenticationService,
  LocalStorageService,
} from './services';


@Injectable()
export class AdminAuthGuard implements CanActivate {

  constructor(
    private router: Router,
    private auth: AuthenticationService,
  ) { }

  canActivate(route: ActivatedRouteSnapshot, state: RouterStateSnapshot): Observable<boolean>|boolean {
    if (this.auth.isFinishedCheckState) {
      return this.authorizedRouting(state);
    }

    // 未認証時は認証チェックして判断する
    return this.auth.checkState()
      .pipe(
        map(res => this.authorizedRouting(state)),
        catchError(err => {
          // 未妊省の状態なのでログイン画面に遷移させる
          this.router.navigate(['/login'], { queryParams: { returnUrl: state.url }});
          return of(false);
        })
      );
  }

  authorizedRouting(state: RouterStateSnapshot): boolean {
    if (!this.auth.isLogin()) {
      // ログイン後に元々表示しようとしていた画面を表示させる
      this.router.navigate(['/login'], { queryParams: { returnUrl: state.url }});
      return false;
    }

    if (!this.auth.isAdmin()) {
      // 権限エラーページに遷移させる
      this.router.navigate(['/error', '403']);
      return false;
    }

    return true;
  }
}