var http = createRequestObject();


function createRequestObject() {
   var ro = false;
    if (window.XMLHttpRequest)
    {
        // Si es Mozilla, Safari etc
        ro = new XMLHttpRequest ();
    } else if (window.ActiveXObject)  {
        // pero si es IE
        try 
        {
            ro = new ActiveXObject ("Msxml2.XMLHTTP");
        }
        catch (e)
        {
            // en caso que sea una versión antigua
            try
            {
            
                ro = new ActiveXObject ("Microsoft.XMLHTTP");
            }
            catch (e)
            {
                alert('No soporta ajax');
                return false;
            }
        }
    }  else{
        return false;
    }

    return ro;
}

function trim(cadena) {
	for(i=0; i<cadena.length; ) {
		if(cadena.charAt(i)==" ")
			cadena=cadena.substring(i+1, cadena.length);
		else
			break;
	}
  for(i=cadena.length-1; i>=0; i=cadena.length-1) {
		if(cadena.charAt(i)==" ")
			cadena=cadena.substring(0,i);
		else
			break;
	}

	return cadena;
}

function sndReq(url) {
	url = url + "&ms=" + new Date().getTime();
    
    http.open('GET', url);
    http.onreadystatechange = handleResponse;
    http.send(null);
}

function handleResponse() {
    if(http.readyState == 4){
        var response = http.responseText;
        var update = new Array();
		var e=null;

        if(response.indexOf('|' != -1)) {
            update = response.split('|');
            e=document.getElementById(update[0]);
            
            e.innerHTML = update[1];
            e.style.display="block";
        }
	
    }
    document.getElementById('ajaxWorking').style.display="none";
}

function muestraFormulario() {
	document.getElementById('ajaxWorking').style.display="block";
	document.getElementById('formulario').style.display="none";
	var plan = document.getElementById('plan').value;
	url='libs/ajax.php?action=cambiaform&plan=' + plan;
	sndReq(url);
}