//intercepts all inbound/outbound ajax data
evoapp.factory('httpInterceptor', function ($rootScope, $q){

    //http://endlessindirection.wordpress.com/2013/05/19/angularjs-global-loading-message-with-http-interceptors/

    var activeRequests = 0;

    var started = function(broadcastEvents){
        
        if(activeRequests == 0 && broadcastEvents === true) 
        {            
            $rootScope.$broadcast('loadingStatusActive');
        } 
        
        activeRequests++;
    };

    var ended = function(response){
        
        //intercept exceptions
        if(response.data.success != undefined)
        {
            if(response.data.messages.length > 0)
            {
                var firstMessage = response.data.messages[0];

                if(firstMessage.type == 'SESSIONTIMEOUT')
                {
                    $rootScope.$broadcast('onsessiontimeout', {response: response.data});
                }
            }
        }

        activeRequests--;

        if(activeRequests==0) 
        {            
            $rootScope.$broadcast('loadingStatusInactive');
        }
    };

    return {
        request: function (config){

            started(config.$$broadcastEvents);

            return config || $q.when(config);
        },
 
        // On request failure
        requestError: function (rejection){
            ended(rejection);
            return $q.reject(rejection);
        },
 
        // On response success
        response: function (response){
            ended(response);
            return response || $q.when(response);
        },
 
        // On response failure
        responseError: function (rejection){
            ended(rejection);
            return $q.reject(rejection);
        }
    };
});

//instantiate httpInterceptor
evoapp.config(function ($httpProvider){

    $httpProvider.interceptors.push('httpInterceptor');
});