Ionic modal return promise after close

ionic-v1
1

I have a login modal that opens up every time an unlogged user navigates to a page that requires login.

angular.module('petSpot', ['ionic', 'ngCordova', 'ngMaterial', 'ngMessages', 'ngTouch', 'ui.bootstrap', 'petSpot.controllers', 'petSpot.directives', 'petSpot.services'])

.run(function ($ionicPlatform, $cordovaStatusbar, $rootScope, $state, $ionicModal, Session, loginModal) {
    $ionicPlatform.ready(function() {
        //Build login modal
        $ionicModal.fromTemplateUrl('templates/login.html', {
            scope: $rootScope
        }).then(function (modal) {
            $rootScope.loginModal = modal;
        });

        $rootScope.$on('$stateChangeStart', function (event, toState, toParams) {
            var requireLogin = toState.data.requireLogin;

            if (requireLogin && typeof $rootScope.currentUser === 'undefined') {
                event.preventDefault();

                loginModal()
                  .then(function () {
                      return $state.go(toState.name, toParams);
                  })
                  .catch(function () {
                      // do nothing
                  });
            }
        });
    })

I want that If the modal closes without the user logging in, a rejected promise will be returned and the navigation will not be approved. If the user successfuly logs in, I want the modal to close and to return a resolved promise.

This is my login modal service:

angular.module('petSpot.services')
    .service('loginModal', function ($ionicModal, $rootScope, $q, $resource) {

        function assignCurrentUser (user) {
            $rootScope.currentUser = user;
            return user;
        }

        return function () {
            var defer = $q.defer();

            $rootScope.loginModal.show().then(function () { // THIS IS NO GOOD
                defer.resolve();
                
            })
            .catch(function () {
                defer.reject(error);
            });
            
            
            return defer.promise;
        };

    });

Any help would be very appreciated!