/* The following function creates an XMLHttpRequest object... */

function createRequestObject(){
	var request_o; //declare the variable to hold the object.
	var browser = navigator.appName; //find the browser name
	if(browser == "Microsoft Internet Explorer"){
		/* Create the object using MSIE's method */
		request_o = new ActiveXObject("Microsoft.XMLHTTP");
	}else{
		/* Create the object using other browser's method */
		request_o = new XMLHttpRequest();
	}
	return request_o; //return the object
}

/* You can get more specific with version information by using 
	parseInt(navigator.appVersion)
	Which will extract an integer value containing the version 
	of the browser being used.
*/
/* The variable http will hold our new XMLHttpRequest object. */
var http = createRequestObject(); 

/* Function called to get the product categories list */
function getModels(action, make){
	/* Create the request. The first argument to the open function is the method (POST/GET),
		and the second argument is the url... 
		document contains references to all items on the page
		We can reference document.form_category_select.select_category_select and we will 		
		be referencing the dropdown list. The selectedIndex property will give us the 
		index of the selected item. 
	*/
	http.open('get', '/cms/thesite/public/resources/scripts/ajax.php?action='+action+'&make='+make);
	/* Define a function to call once a response has been received. This will be our
		handleProductCategories function that we define below. */
	http.onreadystatechange = handleModels; 
	/* Send the data. We use something other than null when we are sending using the POST
		method. */
	http.send(null);
}

/* Function called to handle the list that was returned from the internal_request.php file.. */
function handleModels(){
	/* Make sure that the transaction has finished. The XMLHttpRequest object 
		has a property called readyState with several states:
		0: Uninitialized
		1: Loading
		2: Loaded
		3: Interactive
		4: Finished */

	if(http.readyState == 4){ //Finished loading the response
		/* We have got the response from the server-side script,
			let's see just what it was. using the responseText property of 
			the XMLHttpRequest object. */
		var response = http.responseText;
		/* And now we want to change the product_categories <div> content.
			we do this using an ability to get/change the content of a page element 
			that we can find: innerHTML. */
		document.getElementById('models').innerHTML = response;
		document.getElementById('turbos').innerHTML = '';
	}
}
/* Andrew */
function handleOnChange(dd1){
	var idx = dd1.selectedIndex;
 	var val = dd1[idx].text;
  	var par = document.forms["catalogue"];
  	var parelmts = par.elements;
  	var models = parelmts["models"];
  	var make = val;
  	getModels('getmodels', make);
}

function handleOnChange2(dd1){
	var idx = dd1.selectedIndex;
 	var val = dd1[idx].text;
  	var model = val;
  	getTurbos(model);
}

function getTurbos(model){
	http.open('get', '/cms/thesite/public/resources/scripts/ajax.php?action=getturbos&model='+model);
	http.onreadystatechange = handleTurbo; 
	http.send(null);
}
function handleTurbo(){
	if(http.readyState == 4){ //Finished loading the response
		/* We have got the response from the server-side script,
			let's see just what it was. using the responseText property of 
			the XMLHttpRequest object.*/ 
		var response = http.responseText;
		/* And now we want to change the product_categories <div> content.
			we do this using an ability to get/change the content of a page element 
			that we can find: innerHTML. */
		document.getElementById('turbos').innerHTML = response;
	}
}