Как сократить процесс формирования заказа до 1 шага?

/* AJAX добавление товара в корзину */
if (isset($_GET['ajax_add_item_id']))

/* AJAX добавление товара в корзину */
if (isset($_GET['ajax_add_item_id']))
{
   $fio1 = substr(quote_smart(to_str($_GET['fio'])), 0, 255);
   $phone1 = substr(quote_smart(to_str($_GET['phone'])), 0, 255);
   $email1 = substr(quote_smart(to_str($_GET['email'])), 0, 255);
   $item_id1 = to_int($_GET['ajax_add_item_id']);
   
   $item_row1 = $shop->getItem($item_id1);
   
   if (!$item_row1/* || $fio1 == '' || $phone1 == '' || $email1 == ''*/) {
      // Отображаем неудачу
      $JsHttpRequest = new JsHttpRequest('UTF-8');

      ob_start();      
      if (!$item_row1) {
         echo "item_id";
      } else if ($fio1 == '') {
         echo "fio";
      } else if ($phone1 == '') {
         echo "phone";
      } else if ($email1 == '') {
         echo "email";
      }
      $error_html = ob_get_clean();
      
      $GLOBALS['_RESULT'] = array('cart' => $error_html);
      echo $JsHttpRequest->LOADER;
      exit();
   }
   
   // Create order in db
   $param = array();
   $param['shop_shops_id'] = $shop_id;
   $param['shop_system_of_pay_id'] = 16;
   $param['shop_order_users_name'] = $fio1;
   $param['shop_order_users_email'] = $email1;
   $param['phone'] = $phone1;
   $param['description'] = quote_smart(to_str($_GET['add_info']));
   $param['shop_order_ip'] = '127.0.0.1';
   /*$param['system_information'] = 'Дополнительная инфромация - system_information';*/
   $order_id1 = $shop->InsertOrder($param);
   
   // Add item to order
   $param = array();
   $param['shop_order_id'] = $order_id1;
   $param['shop_items_catalog_item_id'] = $item_id1;
   $param['shop_order_items_quantity'] = 1;
   $param['shop_order_items_price'] = $item_row1['shop_items_catalog_price'];
   $param['shop_order_items_name'] = $item_row1['shop_items_catalog_name'];
   $param['shop_order_items_type'] = 0;
   $shop->InsertOrderItems($param);
   
   // Send email to admin and client
   $param = array();
   $param['admin-content-type'] = 'html';
   $param['user-content-type'] = 'html';
   
   $shop->SendMailAboutOrder($shop_id, $order_id1, $site_users_id, 'ПисьмоАдминистратору', 'ПисьмоПользователю', $email1, $param);
   
   ///////////////////////////////////////////////
   
   // Отображаем результат "ок"
   $JsHttpRequest = new JsHttpRequest('UTF-8');

   ob_start();
      echo "ok";
   $little_cart_html = ob_get_clean();

   $GLOBALS['_RESULT'] = array('cart' => $little_cart_html);

   echo $JsHttpRequest->LOADER;
   exit();
}