dspies/ua-security-state-manager

'use strict';

angular.module('ua.security')
  .provider('stateManager', [function stateManagerProvider(){

    var loginStateName = 'login';
    this.setLoginStateName = function (stateName) {
      loginStateName = stateName;
    };

    var homeStateName = 'home';
    this.setHomeStateName = function (stateName) {
      homeStateName = stateName;
    };

    var unauthorizedStateName = 'unauthorized';
    this.setUnauthorizedStateName = function (stateName) {
      unauthorizedStateName = stateName;
    };

    function stateManagerFactory(securityService, $state, $rootScope) {

      var loggedIn = function () {
        return securityService.isAuthenticated();
      };

      var goToLoginState = function () {
        $state.go(loginStateName);
      };

      var goToHomeState = function () {
        $state.go(homeStateName);
      };

      var goToUnauthorizedState = function () {
        $state.go(unauthorizedStateName);
      };

      var stateRequiresAuthorization = function(state){
        return 'roles' in state;
      };

      var authorizedToTransitionTo = function (toState) {
        return !stateRequiresAuthorization(toState) || currentUserIsAllowed(toState);
      };

      var currentUserIsAllowed = function (state) {
        return securityService.hasAnyRoles(state.roles);
      };

      //TODO Create overridable/configurable handler
      var stateChangeStartAuthorizationInterceptor = function(event, toState, toParams, fromState, fromParams) {
        if (!authorizedToTransitionTo(toState)){
          event.preventDefault();

          //TODO Allow multiple 'unauthorizedStateChange' handlers (in order to perform functions like logging)
          unauthorizedStateChange(event, toState, toParams, fromState, fromParams);
        }
      };

      //TODO Create overridable/configurable handler
      var unauthorizedStateChange = function (event, toState, toParams, fromState) {

        if (!atLoginState(fromState)){
          if (loggedIn()){
            goToUnauthorizedState();
          } else {
            goToLoginState();
          }
        }
      };

      var atLoginState = function (state) {
        return state.name === loginStateName;
      };

      var initialize = function() {
        //Register route authorization handler
        $rootScope.$on('$stateChangeStart', function(event, toState, toParams, fromState, fromParams) {
          stateChangeStartAuthorizationInterceptor(event, toState, toParams, fromState, fromParams);
        });
      };

      return {
        loggedIn: loggedIn,
        authorizedToTransitionTo: authorizedToTransitionTo,
        stateRequiresAuthorization: stateRequiresAuthorization,
        goToHomeState: goToHomeState,
        goToLoginState: goToLoginState,
        goToUnauthorizedState: goToUnauthorizedState,
        init: initialize
      };

    }
    stateManagerFactory.$inject = ['securityService', '$state', '$rootScope'];

    this.$get = stateManagerFactory;
  }])
  .run(['stateManager', function stateManagerInitialization(stateManager){
    stateManager.init();
  }]);