var xmlhttp
var string="";
function showHint(str)
{
	if(str=="")
	{	
		Discount=0;
		Total=SubTotal;
		document.getElementById('SubTotal').innerHTML="$"+format_number(Total,2);
	}
	else
	{
		document.getElementById("txtHint").innerHTML="waiting...";
		string=str;
		if (str.length==0)
		{
		document.getElementById("txtHint").innerHTML="";
		return;
		}
		xmlhttp=GetXmlHttpObject();
		if (xmlhttp==null)
		{
		alert ("Your browser does not support XMLHTTP!");
		return;
		}
		var url="desc_promocode.php";
		url=url+"?q="+str;
		url=url+"&sid="+Math.random();
		xmlhttp.onreadystatechange=stateChanged;
		xmlhttp.open("GET",url,true);
		xmlhttp.send(null);
	}
}

function stateChanged()
{
if (xmlhttp.readyState==4)
  {
	var result=xmlhttp.responseText;
	document.getElementById("txtHint").innerHTML=result;
	if(result=="This code is invalid or expired"||result=="")
	{	
		Discount=0;
		Total=SubTotal;
		document.getElementById('SubTotal').innerHTML="$"+format_number(Total,2);
	}
	else
	{
		getdiscount(string);
		document.getElementById('SubTotal').innerHTML="waiting...";
		
	}
  }
}
//--------------------------------------
function getdiscount(str)
{
	var url="desc_promocode.php?task=getDiscount";
	url=url+"&q="+str;
	url=url+"&sid="+Math.random();
	xmlhttp.onreadystatechange=stateChanged1;
	xmlhttp.open("GET",url,true);
	xmlhttp.send(null);

}

function stateChanged1()
{
if (xmlhttp.readyState==4)
  {
	var result=xmlhttp.responseText;
	GetDiscount(result);//alert(xmlhttp.responseText);
  }
}
//---------------------------------------
function GetXmlHttpObject()
{
if (window.XMLHttpRequest)
  {
  // code for IE7+, Firefox, Chrome, Opera, Safari
  return new XMLHttpRequest();
  }
if (window.ActiveXObject)
  {
  // code for IE6, IE5
  return new ActiveXObject("Microsoft.XMLHTTP");
  }
return null;
}