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public function addToShoppingCart()
{

        if ($this->context->cart->id){
            $id_cart = $this->context->cart->id;
        }

        if (!$id_cart){ // not exists, create
            $cart = new Cart();
            $cart->id_customer = (int)($this->context->cookie->id_customer);
            $cart->id_lang = (int)($this->context->cookie->id_lang);
            $cart->id_currency = (int)($this->context->cookie->id_currency);
            $cart->id_carrier = 1;
            $cart->recyclable = 0;
            $cart->gift = 0;
            $cart->gift_message = Tools::getValue('svgTemplateResult');
            $cart->add();
            $this->context->cookie->__set('id_cart', $cart->id);   
            $data = [
               'cart' => $cart,
               'product' => $product,
               'id_product_attribute' => $id_product_attribute,
               'id_customization' => $id_customization,
               'quantity' => '1',
               'operator' => 'up',
               'id_address_delivery' => (int)(Address::getFirstCustomerAddressId($cart->id_customer)),
               'id_address_invoice' => (int)(Address::getFirstCustomerAddressId($cart->id_customer)),
               'shop' => $this->context->shop->id,
               'auto_add_cart_rule' => true,
            ];

             Hook::exec('actionCartUpdateQuantityBefore', $data);
        } else { // exists, update
           $cart = new Cart ((int) $id_cart);
           $cart->gift_message = Tools::getValue('svgTemplateResult');
           $cart->update();
        }

        
    }