if($_GET['method'] == 'register')
{
  if(isset($_GET['amount']) & isset($_GET['guest_name']) & isset($_GET['phone']) & isset($_GET['room']) & isset($_GET['arrival']))
  {
    if(!empty($_GET['amount']) & !empty($_GET['guest_name']) & !empty($_GET['phone']) & !empty($_GET['room']) & !empty($_GET['arrival']))
    {
      $ch = curl_init();
      curl_setopt($ch, CURLOPT_URL, $main_server.$register.'?userName='.$merchant['login'].'&password='.$merchant['password'].'&amount='.$_GET['amount'].'&orderNumber='.$orderNumber.'&returnUrl='.$returnUrl);
      curl_setopt($ch, CURLOPT_HEADER, false);
      curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
      curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 30);
      curl_setopt($ch, CURLOPT_USERAGENT, 'PHP Gateway ');
      curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
      curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, false);
      $data = curl_exec($ch);
      curl_close($ch);
      $data_arr = json_decode($data, true);

      if(isset($data_arr['errorCode']) & !empty($data_arr['errorCode']))
      {
        die('Произошла ошибка: ' . $data_arr['errorCode'] . ' : ' . $data_arr['errorMessage']);
      }
      else
      {
        header("Location: " . $data_arr['formUrl']);
        exit();
      }
    }
    else
    {
      die("Один или несколько параметров пусты");
    }

  }
  else
  {
    die("Один или несколько параметров не заданы");
  }
}

error_reporting(E_ALL);