function CartItemAdd(id) {
	var anz = $('p'+id);
	var cnt = anz.options[anz.selectedIndex].text;
	
	new Ajax.Request('/ajax.asp', { 
		method: 'get', 
		parameters: { action: 'Cart_addItem', id: id, anzahl: cnt }, 
		onSuccess: function(transport) { var json = transport.responseText.evalJSON(); updateShopItemCounts(id, json.item); updateCartSummary(json.cart); }
	}); 
}

function CartItemChange(id, offset) {
	new Ajax.Request('/ajax.asp', { 
		method: 'get', 
		parameters: { action: 'Cart_changeItem', id: id, anzahl: offset }, 
		onSuccess: function(transport) { var json = transport.responseText.evalJSON(); updateCartTotals(json.cart); updateCartItemCounts(id, json.item); updateCartSummary(json.cart); }
	}); 
}

function CartItemDel(id) {
	new Ajax.Request('/ajax.asp', { 
		method: 'get', 
		parameters: { action: 'Cart_deleteItem', id: id }, 
		onSuccess: function(transport) { var json = transport.responseText.evalJSON(); removeCartItem(id); updateCartTotals(json.cart); updateCartSummary(json.cart); }
	}); 
}

function updateShopItemCounts(id, item) {
	$('p'+id+'_anz').innerHTML = (item.count > 0 ? item.count + " Stück im Korb" : "");
}

function updateCartItemCounts(id, item) {
	$('p'+id+'_anz').innerHTML = item.count;
	$('p'+id+'_sum').innerHTML = formatMoney(item.total);
//	$('prod_anz'+id).value = item.count;
}

function removeCartItem(id) {
	Element.remove($('p'+id));
}

function updateCartTotals(cart) {
	$('subtotal').innerHTML = formatMoney(cart.subtotal);
	$('shipping').innerHTML = formatMoney(cart.shipping);
	$('total').innerHTML = formatMoney(cart.total);

	if (cart.subtotal == 0) {
		$('shipping').innerHTML = formatMoney(0);
		$('total').innerHTML = formatMoney(0);
		$('continue').disable();
		if (cart.empty)
			$('emptycart').show();
	}
	else {
		$('continue').enable();
	}
}

function updateCartSummary(cart) {
	$('shopcart').innerHTML = cart.text;
}

function formatMoney(price) {
	return price.toFixed(2);
}