function getUserScore(){
	var userName = document.getElementById('user_ranking').value;
	
	if ( userName == '' ){
		alert('Debe introducir el apodo de algún usuario.');
		return false;
	}
	
	 var url =  Alfresco.constants.PROXY_URI + "api/people/" + userName;

     // execute ajax request
     Alfresco.util.Ajax.request(
     {
        url: url,
        method: "GET",
        responseContentType : "text",
        successCallback:
        {
           fn: onSuccess,
           scope: this
        },
        failureCallback:
        {
           fn: onFailure,
           scope: this
        }
     });
     
    
}

function onSuccess(response){
	var resp = response.json;
	if ( resp != null ){
		 var div = document.getElementById('userRankingResult');
		 div.innerHTML = '<h2>El usuario ' + resp.userName + ' tiene ' + resp.score + ' puntos.<h2>';
		 return false;		 
	}
	return false;		    
}

function onFailure(response){		
	var div = document.getElementById('userRankingResult');
	div.innerHTML = '<h2>El usuario no existe</h2>';
	return false;
}