Method addItems

/*
 * Catid is only for information from which place the product was added to the cart
 * When making order, this will be recheck
 */
public function addItems($id = 0, $catid = 0, $quantity = 0, $attributes = array(), $idKey = '')
{
    $app = Factory::getApplication();
    if ($idKey != '') {
        // we get idkey as string - from checkout update or remove -  used in CHECKOUT
    } else {
        // we get id as int standard id of product - attributes can be listed in form - used in CATEGORY, ITEM, ITEMS
        //- $k = (int)$id . ':';
        $checkP = PhocacartProduct::checkIfAccessPossible($id, $catid, $this->type);
        if (!$checkP) {
            //$uri 			= JUri::getInstance();
            //$action			= $uri->toString();
            $app->enqueueMessage(Text::_('COM_PHOCACART_PRODUCT_NOT_ADDED_TO_SHOPPING_CART_NO_RIGHTS_FOR_ORDERING_PRODUCT'), 'error');
            return false;
        }
        // Check if there is required attribute
        // In fact this should not happen in item Online Shop view, as this should be checked per html5 checking form
        // This is security check on server side - e.g. when testing attributes in items or category view
        // But in POS EAN and SKU can be added with help of Advanced stock management so check direct adding of SKU or EAN
        $checkedA = PhocacartAttribute::checkRequiredAttributes($id, $attributes);
        if (!$checkedA) {
            //$uri 			= JUri::getInstance();
            //$action			= $uri->toString();
            $app->enqueueMessage(Text::_('COM_PHOCACART_PRODUCT_NOT_ADDED_TO_SHOPPING_CART_SELECTING_ATTRIBUTE_IS_REQUIRED'), 'error');
            return false;
        }
        /*if (!empty($attributes)) {
        
                        // Remove empty values, so items with empty values (add to cart item view) is the same
                        // like item without any values (add to cart category view)
                        foreach($attributes as $k2 => $v2) {
                            if ($v2 == 0 || $v2 == '') {
                                unset($attributes[$k2]);
                            }
                        }
                        if (!empty($attributes)) {
                            $k .= base64_encode(serialize($attributes));
                        }
                    }
                    $k .= ':';*/
        $k = PhocacartProduct::getProductKey($id, $attributes);
    }
    if ($k != '' && (int) $catid > 0) {
        $this->items[$k]['catid'] = (int) $catid;
    }
    if ($k != '' && (int) $quantity > 0) {
        if (isset($this->items[$k]['quantity']) && (int) $this->items[$k]['quantity'] > 0) {
            $this->items[$k]['quantity'] = $this->items[$k]['quantity'] + (int) $quantity;
        } else {
            $this->items[$k]['quantity'] = (int) $quantity;
        }
        $this->updateItems();
        //$this->updateSubTotal();
        return true;
    } else {
        $app->enqueueMessage(Text::_('COM_PHOCACART_PRODUCT_NOT_ADDED_TO_SHOPPING_CART_QUANTITY_WAS_NOT_SET'), 'error');
    }
    return false;
}