<?php
/**
 * @version $Id: paypal.php
 * @package ImageAds
 * @author Andrey Sokolnikov <aasfalcon@gmail.com>
 * @copyright (C) 2011 Emergination, LLC. All rights reserved.
 * @license http://www.gnu.org/licenses/gpl-3.0.html GNU/GPL
 */

// no direct access
defined('_JEXEC') or die('Restricted access');

/**
 * PayPal button
 *
 * @package ImageAds
 */
 class imageadsPayPalButton
 {
	/**
	 * Command (subscription)
	 *
	 * @var string
	 * @access public
	 */
 	var $cmd = '_xclick-subscriptions';
	
	/**
	 * Seller's email
	 *
	 * @var string
	 * @access public
	 */
	var $business = '';
	
	/**
	 * Location
	 *
	 * @var string
	 * @access public
	 */
	var $lc = 'us';
	
	/**
	 * Item name
	 *
	 * @var string
	 * @access public
	 */
	var $item_name = '';
	
	/**
	 * Item ID
	 *
	 * @var int
	 * @access public
	 */
	var $item_number = 0;
	
	/**
	 * Disable note
	 *
	 * @var bool
	 * @access public
	 */
	var $no_note = true;
	
	/**
	 * Disable shipping
	 *
	 * @var bool
	 * @access public
	 */
	var $no_shipping = true;
	
	/**
	 * Source (?)
	 *
	 * @var bool
	 * @access public
	 */
	var $src = 1;
	
	/**
	 * Subscription payment amount
	 *
	 * @var string
	 * @access public
	 */
	var $a3 = '0.00';
	
	/**
	 * Subscription period
	 * 
	 * @var int
	 * @access public
	 */
	var $p3 = '1';
	
	/**
	 * Subscription period type (day, month...)
	 * 
	 * @var string
	 * @access public
	 */
	var $t3 = 'M';
	
	/**
	 * Currency code
	 * 
	 * @var string
	 * @access public
	 */
	var $currency_code = 'USD';
	
	/**
	 * Button type
	 * 
	 * @var string
	 * @access public
	 */
	var $bn = 'PP-SubscriptionsBF:btn_subscribeCC_LG.gif:NonHosted';
	
	/**
	 * Return method (1 - GET, 2 - POST)
	 * 
	 * @var int
	 * @access public
	 */
	var $rm = 2;
	
	/**
	 * Cancel return URL
	 * 
	 * @var string
	 * @access public
	 */
	var $cancel_return = null;
	
	/**
	 * Notify URL
	 * 
	 * @var string
	 * @access public
	 */
	var $notify_url = null;
	
	/**
	 * Return URL
	 * 
	 * @var string
	 * @access public
	 */
	var $return = null;
	
	/**
	 * Return URL
	 * 
	 * @var string
	 * @access public
	 */
	var $cbt = null;
	
	/**
	 * PayPal URL
	 * 
	 * @var string
	 * @access private
	 */
	var $_paypal_url = IA_PAYPAL_URL;
	
	/**
	 * Constructor
	 * 
	 * @access public
	 */
	function __construct()
	{
		$params = JComponentHelper::getParams(IA_OPTION);
		
		$this->a3			= $params->get('ad_price');
		$this->business		= $params->get('paypal_email');
    $this->site_name  = $params->get('site_name');
    $this->cbt        = sprintf( JText::_('COM_IMAGEADS_RETURNTO_SUCCESS'), $params->get('site_name') );
		
		if ($params->get('paypal_sandbox')) {
			$this->_paypal_url = IA_PAYPAL_URL_SANDBOX;
		}
	}
	
	/**
	 * Get button HTML
	 * 
	 * @access public
	 * @return string
	 */
	function render()
	{
		if (!$this->business) {
			return JText::_('COM_IMAGEADS_UNCONFIGURED');
		}
		
		// begin form
		$button = "<form action=\"https://{$this->_paypal_url}/cgi-bin/webscr\" method=\"post\" class=\"ia-paypal-button\">";
		$vars = get_object_vars($this);
		
		// add hidden inputs
		foreach ($vars as $key => $value) {
			if (substr($key, 0, 1) != '_') { // skip private vars
				if (isset($value)) {
					$button .= "\n<input type=\"hidden\" name=\"$key\" value=\"$value\" />";
				}
			}
		}
		
		// add image, end form
		$button .= "\n<input type=\"image\" "
			."src=\"https://{$this->_paypal_url}/en_US/i/btn/btn_subscribeCC_LG.gif\" "
			."border=\"0\" name=\"submit\" alt=\"".JText::_('COM_IMAGEADS_SUBSCRIPTION_BUTTON_ALT')."\">";
		$button .= "\n<img alt=\"\" border=\"0\" src=\"https://{$this->_paypal_url}/en_US/i/scr/pixel.gif\" width=\"1\" height=\"1\">";
		$button .= "\n</form>";
		
		return $button;
	}
 }
  
/**
 * PayPal payments helper class
 *
 * @package ImageAds
 */
class imageadsPayPal
{
	/**
	 * Create PayPal subscribe button
	 * 
	 * @static
	 * @access public
	 * @param string $item_name Item name shown on PayPal site
	 * @param int $item_id Item id number
	 * @param string $cancel_url URL to return on payment cancellation
	 * @param string $notify_url URL to recieve IPN
	 * @param string $return_url URL to return on successfull payment
	 * @return string Button HTML
	 */
	static function getButton($item_name, $item_id, $cancel_url, $notify_url, $return_url)
	{
		$button = new imageadsPayPalButton();
		$button->item_name = sprintf(JText::_('COM_IMAGEADS_SUBSCRIPTION_ITEM_NAME'), $button->site_name, $item_name);
		$button->item_number = $item_id;
		$button->cancel_return = $cancel_url;
		$button->notify_url = $notify_url;
		$button->return = $return_url;
		return $button->render();
	}
	
	/**
	 * Validate PayPal IPN
	 * 
	 * @static
	 * @access public
	 * @param int &$validate_result Validation result (one of IA_PAYPAL_VALIDATE_IPN_XXX constants)
	 * @return JRegistry object to store IPN data
	 */
	static function &validateIPN(&$validate_result)
	{
		// read the post from PayPal system and add 'cmd'
		$req = 'cmd=_notify-validate';
		
		foreach (JRequest::get('post') as $key => $value) {
			$value = urlencode(stripslashes($value));
			$req .= "&$key=$value";
		}
		
		// post back to PayPal system to validate
		$header = "POST /cgi-bin/webscr HTTP/1.0\r\n";
		$header .= "Content-Type: application/x-www-form-urlencoded\r\n";
		$header .= "Content-Length: " . strlen($req) . "\r\n\r\n";
		$fp = fsockopen ('ssl://www.paypal.com', 443, $errno, $errstr, 30);
		
		$validate_result = IA_PAYPAL_VALIDATE_IPN_ERROR;
		
		if ($fp) {
			fputs ($fp, $header . $req);
			
			while (!feof($fp)) {
				$response = fgets ($fp, 1024);
				
				if ("VERIFIED" == $response) {
					$validate_result = IA_PAYPAL_VALIDATE_IPN_VERIFIED;
				} elseif ("INVALID" == $response) {
					$validate_result = IA_PAYPAL_VALIDATE_IPN_INVALID;
				}
			}
			
			fclose ($fp);
		}
		
		$ipn = new JRegistry();
		$ipn->loadArray(JRequest::get('post'));		
		return $ipn; 
	}
}