import { Inject, Injectable, Injector } from '@angular/core';
import { ActivatedRouteSnapshot, CanActivate, CanActivateChild, CanLoad, Route, RouterStateSnapshot, UrlSegment } from '@angular/router';
import { CheckJwt, ToLogin } from '../helper';
import { BIXI_SERVICE_TOKEN, ITokenService } from '../interface';
import { JWTTokenModel } from './jwt.model';

/**
 * JWT 路由守卫, [ACL Document](https://bixi.datagrand.com/auth/guard).
 *
 * ```ts
 * data: {
 *  path: 'home',
 *  canActivate: [ JWTGuard ]
 * },
 * {
 *   path: 'my',
 *   canActivateChild: [JWTGuard],
 *   children: [
 *     { path: 'profile', component: MockComponent }
 *   ],
 * },
 * ```
 */
@Injectable({ providedIn: 'root' })
export class JWTGuard implements CanActivate, CanActivateChild, CanLoad {
  private url: string | undefined;

  private get cog() {
    return this.srv.options;
  }

  constructor(@Inject(BIXI_SERVICE_TOKEN) private srv: ITokenService, private injector: Injector) { }

  private process(): boolean {
    // tslint:disable-next-line:no-non-null-assertion
    const res = CheckJwt(this.srv.get<JWTTokenModel>(JWTTokenModel), this.cog.token_exp_offset!);
    if (!res) {
      console.warn('[@bixi/auth](jwt guard): token 不存在或已过期，前往登录页');
      ToLogin(this.cog, this.injector, this.url);
    }
    return res;
  }

  // lazy loading
  canLoad(route: Route, _segments: UrlSegment[]): boolean {
    this.url = route.path;
    return this.process();
  }
  // all children route
  canActivateChild(_childRoute: ActivatedRouteSnapshot, state: RouterStateSnapshot): boolean {
    this.url = state.url;
    return this.process();
  }
  // route
  canActivate(_route: ActivatedRouteSnapshot, state: RouterStateSnapshot): boolean {
    this.url = state.url;
    return this.process();
  }
}