//функция возвращает экземпляр класса XMLHttpRequest
function getHTTPRequestObject() {
	var xmlHttpRequest;
	if (typeof ActiveXObject != 'undefined') {
		xmlHttpRequest = new ActiveXObject('Microsoft.XMLHTTP');
	} else if (typeof XMLHttpRequest != 'undefined') {
		xmlHttpRequest = new XMLHttpRequest();
	} else {
		xmlHttpRequest = false;
	}
	return xmlHttpRequest;
}

var httpRequester = getHTTPRequestObject(); //Рабочий экземпляр класса XMLHttpRequest

    //выполняет асинхронный GET
function makeAJAXCall(ajaxUrl){
	if (httpRequester) {
		httpRequester.open("GET", ajaxUrl, true);
		httpRequester.onreadystatechange = processResponse;
		httpRequester.send(null);
	}
}
var READY_STATE_COMPLETE=4;

//CallBack-функция. Выводит полученные асинхронно данные или сообщение об ошибке
function processResponse() {
	if (httpRequester.readyState == READY_STATE_COMPLETE) {
		if (httpRequester.status==200) {
	
			res = httpRequester.responseText.split(";");
			res[2] = parseInt(res[2]);
			img_cart = document.getElementById("get_cart_img").value;

			curr_symb = document.getElementById("currency_symb").value;
			lbl_update = document.getElementById("get_lbl_update").value;
			lbl_addtocart = document.getElementById("get_lbl_addtocart").value;
			lbl_only_avail_amount_add = document.getElementById("get_lbl_only_avail_amount_add").value;
			c_amount = document.getElementById("amount_"+res[2]).value;
			
			if (parseInt(c_amount) > parseInt(res[1])) alert(lbl_only_avail_amount_add);

			if (res[1] != 0 && c_amount != 0)
			{
				printToPage (lbl_update,res[2],res[1]);
				document.getElementById("lbl_total").innerHTML = document.getElementById("get_lbl_total").value;

				if (document.getElementById("comma").value == 1)
				document.getElementById("lbl_items").innerHTML = document.getElementById("get_lbl_items").value;
				else
				document.getElementById("lbl_items").innerHTML = document.getElementById("get_lbl_items").value + ",";
				//document.getElementById("cart_img").innerHTML = "<img src='"+img_cart+"'>";
				document.getElementById("c_total").innerHTML = curr_symb + res[0];
				document.getElementById("i_total").innerHTML = res[1];
			}
			else if (res[1] != 0 && c_amount == 0)
			{
				printToPage (lbl_addtocart,res[2],c_amount);
				document.getElementById("lbl_total").innerHTML = document.getElementById("get_lbl_total").value;

				if (document.getElementById("comma").value == 1)
				document.getElementById("lbl_items").innerHTML = document.getElementById("get_lbl_items").value;
				else
				document.getElementById("lbl_items").innerHTML = document.getElementById("get_lbl_items").value + ",";
				//document.getElementById("cart_img").innerHTML = "<img src='"+img_cart+"'>";
				document.getElementById("c_total").innerHTML = curr_symb + res[0];
				document.getElementById("i_total").innerHTML = res[1];

				document.getElementById("amount_"+res[2]).value="1";
			}
			else
			{
				printToPage (lbl_addtocart,res[2],c_amount);
				document.getElementById("amount_"+res[2]).value="1";
				document.getElementById("cart_totals").style.display = "none";
				document.getElementById("cart_empty").style.display = "inline";
			}


		} else {
			var message = "Problem retrieving data. requestStatus="+httpRequester.status+". Message="+httpRequester.statusText;
			printToPage ("<font color=\"red\">"+message+"</font>");
		}
	}
}

//Выводим переданный HTML в элемент с id="result"
function printToPage(value,divid,amount){
	if (divid != null)
	resultDiv = document.getElementById("button_title_"+divid);
	resultDiv.innerHTML = "<font class='Button2'>"+value+"</font>";

	td_bg = document.getElementById("toupdate_"+divid);
	//amount = document.getElementById("amount_"+divid).value;
	//curramount = document.getElementById("curramount_"+divid).value;
	amount = parseInt(amount);

	if (amount == 0)
	{
		if (td_bg!=null)
			td_bg.className="Button2";
	}
	else
	{
		if (td_bg!=null)
			td_bg.className="Button2_1";
	}

}


function newrequest(productid,cat,page){

		if (document.getElementById("amount_"+productid) != null)
		{
				amount = document.getElementById("amount_"+productid).value;
				amount = parseInt(amount);
				if (amount == 0 || amount == "" || isNaN(amount))
					amount = 0;
		}

		else
				amount = 0;

		lbl_adding = document.getElementById("get_lbl_adding").value;

				printToPage (lbl_adding,productid);
				makeAJAXCall("cart_small.php?mode=add&productid="+productid+"&cat="+cat+"&page="+page+"&amount="+amount);
    }