function collect_data(){

	//SELECT ALL CHECKBOXES
	var all_check_boxes = document.getElementsByTagName('input');
	
	//SELECT ALL BRANDS
	var selected_brands = 'manufacturer=';
	var unselected_brands = 'no_manufacturer=';
	for(i = 0; i < all_check_boxes.length; i++){
		if(all_check_boxes[i].getAttribute('id') == "brand" && all_check_boxes[i].checked == true){
			selected_brands = selected_brands+all_check_boxes[i].getAttribute('value')+'-';
		} else if(all_check_boxes[i].getAttribute('id') == "brand" && all_check_boxes[i].checked == false) {
			unselected_brands = unselected_brands+all_check_boxes[i].getAttribute('value')+'-';
		}
	}
	
	//SELECT ALL CATEGORIES
	var selected_category = 'category=';
	var unselected_category = 'no_category=';
	for(i = 0; i < all_check_boxes.length; i++){
		if(all_check_boxes[i].getAttribute('id') == "category" && all_check_boxes[i].checked == true){
			selected_category = selected_category+all_check_boxes[i].getAttribute('value')+'-';
		} else if(all_check_boxes[i].getAttribute('id') == "category" && all_check_boxes[i].checked == false) {
			unselected_category = unselected_category+all_check_boxes[i].getAttribute('value')+'-';
		}
	}
	
	//SELECT ALL COMFORT
	var selected_comfort = 'comfort=';
	var unselected_comfort = 'no_comfort=';
	for(i = 0; i < all_check_boxes.length; i++){
		if(all_check_boxes[i].getAttribute('id') == "comfort" && all_check_boxes[i].checked == true){
			selected_comfort = selected_comfort+all_check_boxes[i].getAttribute('value')+'-';
		} else if(all_check_boxes[i].getAttribute('id') == "comfort" && all_check_boxes[i].checked == false) {
			unselected_comfort = unselected_comfort+all_check_boxes[i].getAttribute('value')+'-';
		}
	}
	
	//DEBUG
	//alert(selected_brands);
	//alert(selected_category);
	//alert(selected_comfort);
	
	//DISPLAY PRODUCTS
	get_products('ajax/product_display_ajax.php', selected_brands+'&'+unselected_brands+'&'+selected_category+'&'+unselected_category+'&'+selected_comfort+'&'+unselected_comfort, 'product_holder');	
	
}

function GetXmlHttpObject(handler){
	var objXMLHttp=null
	
	if(window.XMLHttpRequest){
		objXMLHttp=new XMLHttpRequest()
	} else if(window.ActiveXObject){
		objXMLHttp=new ActiveXObject("Microsoft.XMLHTTP")
	} 
	
	return objXMLHttp
}

function display_products(target_id){
	
	//TARGET TABLE
	var display_table = document.getElementById(target_id);
	
	//REMOVE OLD LOADING SCREENS
	var loading_screen = document.getElementById('loading'); if(loading_screen){ loading_screen.parentNode.removeChild(loading_screen); }
	
	if(xmlHttp.readyState==4 || xmlHttp.readyState=="complete"){
		
		//RESPONSE
		var xml_doc = xmlHttp.responseText;
		
		//DISPLAY DATA
		display_table.innerHTML = xml_doc;
		
	} else {
		
		//DISPLAY DATA
		td = document.createElement('div');	
		td.setAttribute('id', 'loading');
		td.setAttribute('align', 'center');
		td.style.fontSize = '14pt';
		td.style.fontFamily = 'arial';
		td.innerHTML = 'Please Wait While Your Data Loads<br /><img src="images/loading.gif" />';
		
		//INSERT
		display_table.appendChild(td);
	}
}

function get_products(url, qStr, target_id){
	document.getElementById(target_id).innerHTML = '';
	
	
	xmlHttp=GetXmlHttpObject()
	if(xmlHttp==null){
		alert("Browser does not support HTTP Request");
		return;
	}
	
	url=url+"?"+qStr;
	url=url+"&sid="+Math.random();
	xmlHttp.onreadystatechange = function(){ display_products(target_id) };
	xmlHttp.open("GET",url,true);
	xmlHttp.send(null);
}