public function addEcommerceItem($sku, $name = false, $category = false, $price = false, $quantity = false)
{
// Alter price / qty in case an item with the same SKU is already in the cart
if (!empty($sku) && isset($this->ecommerceItems[$sku])) {
$old = $this->ecommerceItems[$sku];
$price = ($old[3] * $old[4] + $price * $quantity) / ($old[4] + $quantity);
$quantity += $old[4];
}
parent::addEcommerceItem($sku, $name, $category, $price, $quantity);
}
