if (Tools::isSubmit('adprod')){
$f=(int)($_POST["adprod"]);
$r=(int)(Db::getInstance()->getValue('SELECT `product_quantity` FROM `ps_order_detail` WHERE `id_order_detail`='.(int)$f));
$r=$r+1;
Db::getInstance()->Execute('UPDATE `ps_order_detail` SET `product_quantity`=.'(int)($r).' WHERE `id_order_detail`='.(int)$f);       (вот 82 строка)
}