function createObject(){

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

}

function enquiryItem(itemid){
	
	// create an object
	req = createObject();
	
	// load up the loading screen
	document.getElementById('loading').style.display = 'inline';
	document.getElementById('ei_submit').disabled = true;
	formText = document.getElementById('ei_submit').value = 'Loading...';
	
	// send the request
	req.onreadystatechange = function(){ enquiryItemComplete(); }
	req.open("POST", "/callers/enquiry_item.asp", true);
	req.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
	req.send("itemid=" + escape(itemid));
	
	return false;

}

function enquiryItemComplete(){

	if (req.readyState == 4){
	
		document.getElementById('loading').style.display = 'none';
		
		if (document.getElementById('ei_act').value == "add_item"){
			document.getElementById('ei_act').value = "remove_item";
			document.getElementById('ei_submit').value = "Remove from enquiry";
			modifier = 1;
		} else {
			document.getElementById('ei_act').value = "add_item";
			document.getElementById('ei_submit').value = "Add to enquiry";
			modifier = -1;
		}
		
		// enable button
		document.getElementById('ei_submit').disabled = false;
		
		// alter header
		document.getElementById('header-info-greeting').style.display = "none";
		document.getElementById('header-info-basket').style.display = "inline";
		
		// increment number
		val = document.getElementById('header-info-basket-count').innerHTML;
		val = val.replace(" items", "");
		val = val.replace(" item", "");
		
		currentCount = parseInt(document.getElementById('header-info-basket-count').innerHTML);
		currentCount = (currentCount + modifier);
		
		if (currentCount < 0){
			currentCount = 0;
		}
		
		if (currentCount == 1){
			new_text = "1 item";
		} else {
			new_text = currentCount + " items";
		}
		
		document.getElementById('header-info-basket-count').innerHTML = new_text;
		
		// do we need to show the continue paragraph?
		if (currentCount == 0){
			document.getElementById('continue-with-enquiry').style.display = "none";
		} else {
			document.getElementById('continue-with-enquiry').style.display = "block";
		}
		
		// error message
		var result = req.responseText;
		
		if (result != ''){
		
			// send error back
			alert(result);
		
		}
	
	}

}

function imagePreviewClose(){
	document.getElementById('larger-image').style.display = "none";
	return false;
}

function imagePreviewOpen(){
	document.getElementById('larger-image').style.display = "block";
	return false;
}