var in_cart = Array();
var items = Array();

function add_to_cart(item_id, name, n) {
	if (!n) n = 1;

	var cart = document.getElementById("cart");
	var table = document.getElementById("cart-table");
	
	if (!cart) return;
	
	var el = find_in_cart(item_id);

	if (el) {
		el.box.value = n + parseInt(el.box.value);
	} else {
		var amount = document.createElement("input");
		amount.setAttribute("type", "text");
		amount.setAttribute("value", n);
		amount.className = "amount";

		var item = Object();
		item.id = item_id;
		item.box = amount;

		in_cart.push(item);

		var row = table.insertRow(0);

		row.insertCell(0).appendChild(amount);
		row.insertCell(1).innerHTML = name;
		row.insertCell(2).innerHTML = '<a href="javascript:delete_from_cart(' + item_id + ');">x</a>';
	}

	update_cart();
}

function delete_from_cart(item_id) {
	var cart = document.getElementById("cart");
	var table = document.getElementById("cart-table");
	
	if (!cart) return;
	
	var el = find_in_cart(item_id);

	if (el) {
		el.box.value = Math.max(parseInt(el.box.value) - 1, 0);
	} 

	update_cart();
}

function update_cart() {
	var cart = document.getElementById("cart");
	cart.value = '';

	for (var i = 0; i < in_cart.length; ++i) {
		cart.value += in_cart[i].box.value + '*' + in_cart[i].id + ';';
	}
}

function find_in_cart(item_id) {
	for (var i = 0; i < in_cart.length; ++i) {
		if (in_cart[i].id == item_id) {
			return in_cart[i];
		}
	}

	return false;
}