Help for developing a new payment method

<?php
/**
 * @package	HikaShop for Joomla!
 * @version	2.2.3
 * @author	hikashop.com
 * @copyright	(C) 2010-2013 HIKARI SOFTWARE. All rights reserved.
 * @license	GNU/GPLv3 http://www.gnu.org/licenses/gpl-3.0.html
 */
defined('_JEXEC') or die('Restricted access');
?><?php
class plgHikashoppaymentmonetaweb2 extends hikashopPaymentPlugin
{
	var $accepted_currencies = array('EUR');
	var $multiple = true;
	var $name = 'superpay';
	var $pluginConfig = array(
		'username' => array('Terminal ID', 'input'),
		'password' => array('Terminal password', 'input'),
		'domain_name' => array('Main domain name<br><small>(i.e.: http://www.myshop.net)</small>', 'input', 'http://www.myshop.net'),	
		'debug' => array('Test environment', 'boolean', '1')

		);

  
	function onBeforeOrderCreate(&$order, &$do) {
		if(parent::onBeforeOrderCreate($order, $do) === true)
			return true;

		$this->ccLoad();

	$amount = number_format($order->cart->full_total->prices[0]->price_value_with_tax,2,'.','');

	$domain=$this->payment_params->domain_name;
	$pluginPath=$domain."/plugins/hikashoppayment/superpay/";
	
	/* ORDER CODE ??? */
	$theOrderCode=$order->order_id;
	
	$host="test";

/* Start the source code MY PERSONAL BANK */

  $parameters = array(
	  'id' => $this->payment_params->username,
	  'password' => $this->payment_params->password,
	  'operationType' => 'initialize',
	  'amount' => $amount,
	  'currencyCode' => '978',
	  'language' => 'ITA',
	  'responseToMerchantUrl' => $pluginPath.'superpay_notify.php',
	  'recoveryUrl' => $pluginPath.'superpay_recovery.php',
	  'merchantOrderId' => 'Order Num. '.$theOrderCode, // ??? ORDER CODE ???
    'cardHolderName' => '',
    'cardHolderEmail'  => '',
	'description' => '',
    'customField' => ''
	  );

		if(!function_exists('curl_init')){
			$this->app->enqueueMessage('The MonetaWeb2 payment plugin needs the CURL library installed but it seems that it is not available on your server. Please contact your web hosting to set it up.','error');
			return false;
		}


  $curlHandle = curl_init();
  curl_setopt($curlHandle, CURLOPT_URL, 'https://'.$host.'.monetaonline.it/monetaweb/payment/2/xml');
  curl_setopt($curlHandle, CURLOPT_SSL_VERIFYPEER, false);
  curl_setopt($curlHandle, CURLOPT_RETURNTRANSFER, true);
  curl_setopt($curlHandle, CURLOPT_POST, true);
  curl_setopt($curlHandle, CURLOPT_POSTFIELDS, http_build_query($parameters));
  $xmlResponse = curl_exec($curlHandle);
  curl_close($curlHandle);

  $response = new SimpleXMLElement($xmlResponse);
  $paymentId = $response->paymentid;
  $paymentUrl = $response->hostedpageurl;

  $securityToken = $response->securitytoken;

  $setefiPaymentPageUrl = "$paymentUrl?PaymentID=$paymentId";
 // print_r($parameters); exit();
  header("Location: $setefiPaymentPageUrl");

	}

	function onAfterOrderConfirm(&$order,&$methods,$method_id){
		parent::onAfterOrderConfirm($order, $methods, $method_id);
		$this->removeCart = true;

		return $this->showPage('thanks');
	}

	function getPaymentDefaultValues(&$element) {
		$element->payment_name='Credit Card';
		$element->payment_description='You can pay by credit card using this payment method';
		$element->payment_images='MasterCard,VISA,American_Express';

		$element->payment_params->username='';
		$element->payment_params->password='';
		$element->payment_params->ask_ccv = true;
		$element->payment_params->ask_owner = false;
		$element->payment_params->verified_status='confirmed';
	}
}