var subscription_types = [['sub_water_full', '1'], ['sub_water_half', '1']];
var digi_types = [['digi_water_full', '1'], ['digi_water_half', '1'], ['digi_wallpaper_mobile', '1'], ['digi_wallpaper_desktop', '1']];
var print_items_narrow = [['print_4x6', '1440'], ['print_5x7', '1680'], ['print_8x10', '2400'], ['print_11x14', '3080'], ['print_16x20', '3800'], ['print_20x24', '4320'], ['print_24x36', '6120'], ['print_30x40', '6800'], ['print_40x60', '9000']];
var print_items_wide = [['print_4x6', '1440'], ['print_5x7', '1680'], ['print_8x12', '2880'], ['print_12x18', '3420'], ['print_16x20', '3800'], ['print_20x30', '5400'], ['print_24x36', '6120'], ['print_30x40', '6800'], ['print_40x60', '9000']];

function setStyle(eltId, styleProperty, styleValue)
{
    if (document.getElementById(eltId) && document.getElementById(eltId).style[styleProperty])
    {
        document.getElementById(eltId).style[styleProperty] = styleValue;
    }
}

function removeItem(cartId)
{
    var quantityElt  = document.cartform.elements[cartId + '_new_quantity'];

    if (quantityElt)
    {
        quantityElt.value = '0';
        document.cartform.action = '/update_cart.php';
        document.cartform.submit();
    }
}

function checkQuantity(cartId)
{
    var quantityElt  = document.cartform.elements[cartId + '_new_quantity'];
    var quantity     = parseInt(quantityElt.value);

    if (quantity > 1)
    {
        var warn = false;

        if (isItemTypeSubscription(document.cartform.elements[cartId + '_old_type'].value))
        {
            warn = true;
        }
        else
        {
            itemTypeSelectElt = document.cartform.elements[cartId + '_new_type'];

            if (isItemTypeDigitalImage(itemTypeSelectElt.options[itemTypeSelectElt.selectedIndex].value) || 
                isItemTypeSubscription(itemTypeSelectElt.options[itemTypeSelectElt.selectedIndex].value))
            {
                warn = true;
            }
        }

        if (warn)
        {
            quantityElt.value = '1';
            showDialog('Attention', 'You cannot have more than one of this digital item in your cart');
        }
    }
}

function displayItemTypeOptions(itemTypeSelectElt, prefix)
{
    var type = itemTypeSelectElt.options[itemTypeSelectElt.selectedIndex].value;

    if (isItemTypeDigitalImage(type))
    {
        setStyle(prefix + 'item_options_digi', 'display', 'inline');
        setStyle(prefix + 'item_options_subscription', 'display', 'none');
        setStyle(prefix + 'item_options_print', 'display', 'none');
    }
    else if (isItemTypeSubscription(type))
    {
        setStyle(prefix + 'item_options_subscription', 'display', 'inline');
        setStyle(prefix + 'item_options_digi', 'display', 'none');
        setStyle(prefix + 'item_options_print', 'display', 'none');
    }
    else if (isItemTypePrint(type))
    {
        setStyle(prefix + 'item_options_print', 'display', 'inline');
        setStyle(prefix + 'item_options_digi', 'display', 'none');
        setStyle(prefix + 'item_options_subscription', 'display', 'none');
    }
}

function isItemTypeDigitalImage(itemType)
{
    var retval = false;

    for (var i = 0; i < digi_types.length && false == retval; i++)
    {
        if (digi_types[i][0] == itemType)
        {
            retval = true;
        }
    }

    return retval;
}

function isItemTypeSubscription(itemType)
{
    var retval = false;

    for (var i = 0; i < subscription_types.length && false == retval; i++)
    {
        if (subscription_types[i][0] == itemType)
        {
            retval = true;
        }
    }

    return retval;
}

function isItemTypePrint(itemType)
{
    var retval = false;

    for (var i = 0; i < print_items_wide.length && false == retval; i++)
    {
        if (print_items_wide[i][0] == itemType)
        {
            retval = true;
        }
    }

    for (var i = 0; i < print_items_narrow.length && false == retval; i++)
    {
        if (print_items_narrow[i][0] == itemType)
        {
            retval = true;
        }
    }

    return retval;
}