AngularJs UI-Router conditional Otherwise link

For easier handling of redirection of $state,
when our angularJs app handling an unknown $state name,
it'll refer to $urlRouterProvider.otherwise("/"); which have to be written inside "config()".
assuming your angular app is declared as below:

var app = angular.module([]);

app.config(['$urlRouterProvider', function($urlRouterProvider) {
  $urlRouterProvider.otherwise(function($injector, $location) {
    var AuthService= $injector.get("AuthService");
    if (AuthService.isLoggedIn()) {
      return "main";
    } else {
      return "login";
    }
  });
}]);

this allow your otherwise become dynamic depend on the login status of a user. In the code above, AuthService is an example authentication service to help determine if a user is logged in.