Kyoo/src/app/auth/misc/authenticated-guard.service.ts

import { Injectable } from "@angular/core";
import { CanActivate, CanLoad, Router } from "@angular/router";
import { Observable } from "rxjs";
import { AuthService } from "../auth.service";

@Injectable({providedIn: "root"})
export class AuthGuard
{
	public static guards: any[] = [];
	public static defaultPermissions: string[];
	public static permissionsObservable: Observable<string[]>;

	static forPermissions(...permissions: string[]): any
	{
		@Injectable()
		class AuthenticatedGuard implements CanActivate, CanLoad
		{
			constructor(private router: Router, private authManager: AuthService)  {}

			async canActivate(): Promise<boolean>
			{
				if (!await this.checkPermissions())
				{
					await this.router.navigate(["/unauthorized"]);
					return false;
				}
				return true;
			}

			async canLoad(): Promise<boolean>
			{
				if (!await this.checkPermissions())
				{
					await this.router.navigate(["/unauthorized"]);
					return false;
				}
				return true;
			}

			async checkPermissions(): Promise<boolean>
			{
				if (this.authManager.isAuthenticated)
				{
					const perms: string[] = this.authManager.account.permissions;
					for (const perm of permissions) {
						if (!perms.includes(perm))
							return false;
					}
					return true;
				}
				else
				{
					if (AuthGuard.defaultPermissions === undefined)
					{
						try
						{
							await AuthGuard.permissionsObservable.toPromise();
						}
						catch
						{
							AuthGuard.defaultPermissions = null;
						}
					}

					if (!AuthGuard.defaultPermissions)
						return true;

					for (const perm of permissions)
						if (!AuthGuard.defaultPermissions.includes(perm))
							return false;
					return true;
				}
			}
		}

		AuthGuard.guards.push(AuthenticatedGuard);
		return AuthenticatedGuard;
	}
}