function createRequestObject() {
    var ro;
    var browser = navigator.appName;
    if(browser == "Microsoft Internet Explorer"){
        ro = new ActiveXObject("Microsoft.XMLHTTP");
    }else{
        ro = new XMLHttpRequest();
    }
    return ro;
}

var http = createRequestObject();
var show_loader;

function getMaterials(uniqueid, size)
{

	var url = "materials.php";
	var data = "uniqueid=" + uniqueid + "&size=" + size;
	http.open("POST", url, true);
	http.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
    http.send(data);
	http.onreadystatechange = handleDrop;

}

function dropSizes(obj)
{

	var size = obj.value;
	var uniqueid = document.forms.product.uniqueid.value;

	var url = "materials.php";
	var data = "uniqueid=" + uniqueid + "&size=" + size;
	http.open("POST", url, true);
	http.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
    http.send(data);
	http.onreadystatechange = handleDrop;

}

function materialChange(obj)
{

	var material = obj.value;
	initial_details = material.split("---");
	
		  document.getElementById('initial_price').innerHTML = '£' + initial_details[2];
		  document.getElementById('initial_code').innerHTML = initial_details[1];
		  document.forms.product.initial_price.value = initial_details[2];
		  document.forms.product.initial_code.value = initial_details[1];	
	
}


function handleDrop() {
  if (http.readyState == 4) {
    if (http.responseText.indexOf('invalid') == -1) {

      qresults = http.responseText.split("^+^");
	  var count = qresults.length;
	  	  
		  var selbox = document.product.material;
     	  selbox.options.length = 0;	   
		  
		  initial_details = qresults[0].split("---");

		  document.getElementById('initial_price').innerHTML = '£' + initial_details[3];
		  document.getElementById('initial_code').innerHTML = initial_details[2];
		  document.forms.product.initial_price.value = initial_details[3];
		  document.forms.product.initial_code.value = initial_details[2];
		  
			for (var i=0;i<qresults.length;i++)
			{
		      details = qresults[i].split("---");
			  selbox.options[selbox.options.length] = new Option(details[0],details[1]+'---'+details[2]+'---'+details[3]);		      
			}

    }
  }
}