var xmlHttp;

function GetXmlHttpObject()	{
	var xmlHttp=null;
	try	{
	  	// Firefox, Opera 8.0+, Safari
	  	xmlHttp=new XMLHttpRequest();
  	}
	catch (e) {
  		// Internet Explorer
		try	{
			// assume IE6 or older
		    var XmlHttpVersions = new Array("MSXML2.XMLHTTP.6.0",
		                                    "MSXML2.XMLHTTP.5.0",
		                                    "MSXML2.XMLHTTP.4.0",
		                                    "MSXML2.XMLHTTP.3.0",
		                                    "MSXML2.XMLHTTP",
		                                    "Microsoft.XMLHTTP");
		    // try every id until one works
		    for (var i=0; i<XmlHttpVersions.length && !xmlHttp; i++) {
		      try { 
		        // try to create XMLHttpRequest object
		        xmlHttp = new ActiveXObject(XmlHttpVersions[i]);
		      } 
		      catch (e) {} // ignore potential error
		    }
	    }
	  	catch (e)	{
	    	xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
	    }
  	}
	return xmlHttp;
}

/*****************************************************
* Ajax for Transfer Edit Pages
******************************************************/
function ajax_model() { 
	xmlHttp=GetXmlHttpObject();
	if (xmlHttp==null)	{
  		alert ("Your browser does not support AJAX!");
  		return;
  	}
  
  	var comp_id = document.getElementById("car_company").value;

	if(comp_id == "" || comp_id == '0') {
  		var comp_id = document.getElementById("car_company").value;
	}
	if(comp_id == "" || comp_id == '0') {
		alert("Please select a manufacturer / name.");
		return false;
	}// proceed only if the xmlHttp object isn't busy 
	else {
		var company = comp_id;
		var url="ajax_make.php?comp_id=" + company;
		xmlHttp.onreadystatechange = modelResponse;
		xmlHttp.open("GET",url,true);
		xmlHttp.send(null);
	}
}

function modelResponse() { 

	if (xmlHttp.readyState==4)	{
		var response =  xmlHttp.responseText;
		var update = new Array();
		var j = 0;
	
		if (document.getElementById('d_model')) {
			document.getElementById('d_model').style.display = "";
		}
		removeAllOptions(document.frm_search.car_model);
	    if(response.indexOf('|') != -1) {
	    	update = response.split('|');
	    	for(var i=1;i <= (update.length/2);i++)
			{
				addOption(document.frm_search.car_model,update[j], update[j+1]);
			    j= j + 2;
			}
		}
	}
}

function removeAllOptions(selectbox)
{
	var i;
	for(i=selectbox.options.length-1;i>=0;i--)
	{
		selectbox.remove(i);
	}
}

function addOption(selectbox, value, text )
{
	var optn = document.createElement("OPTION");
	optn.text = text;
	optn.value = value;

	selectbox.options.add(optn);
}