function setupAjax(){
	var ajaxPtr;

	try{ // Firefox, Opera 8.0+, Safari
		ajaxPtr = new XMLHttpRequest();
	} catch (e){
		try { // Internet Explorer
			ajaxPtr = new ActiveXObject("Msxml2.XMLHTTP");
		} catch (e) {
			try { // Internet Explorer
				ajaxPtr = new ActiveXObject("Microsoft.XMLHTTP");
			} catch (e) { // Not Compatible
				alert("Your browser does not support AJAX!");
				exit(1);
			}
		}
	}
	return ajaxPtr;
}

function updateAjaxDropdown( brand, type, pattern ){
	var ajaxDropdownData = setupAjax( );
	var dd=document.getElementById( type );

	ajaxDropdownData.onreadystatechange=function() {
		if(ajaxDropdownData.readyState==4) {
			var j=1;
			if ( dd.options.length > 1){ for(i=dd.options.length-1; i>0; i--){ dd.options[i] = null; } }
			if ( (type == "pattern" && brand != "") || (type == "color" && pattern != "") ){
				var optionData=ajaxDropdownData.responseText.split("\n");
				for(i=0; optionData.length > i; i++){
					dd.options[j++] = new Option(optionData[i],optionData[i]);
				}
			}
		}
	}
	ajaxDropdownData.open("GET","js/ajax/ajaxFunctions.php?brand="+brand.toLowerCase()+"&dd="+type+"&pattern="+pattern,true);
	ajaxDropdownData.send(null);
}

function updateAjaxDropdowns( type, style ){
	var ajaxDropdownData = setupAjax( );
	if (type == "style"){
		var dd = new Array();
		for(i=1; document.getElementById( "item"+i ) !== null; i++){
			dd[i]=document.getElementById( "item"+i );
		}
	}

	ajaxDropdownData.onreadystatechange=function() {
		if(ajaxDropdownData.readyState==4) {
			var optionData=ajaxDropdownData.responseText.split("\n");
			for(k=1; dd.length>k; k++){
				var j=1;
				if ( dd[k].options.length > 1){ for(i=dd[k].options.length-1; i>0; i--){ dd[k].options[i] = null; } }
				for(i=0; optionData.length > i; i++){ dd[k].options[j++] = new Option(optionData[i],optionData[i]); }
			}
		}
	}
	ajaxDropdownData.open("GET","js/ajax/ajaxFunctions.php?type="+type+"&style="+style,true);
	ajaxDropdownData.send(null);
}