/modules/paypal/ipn.php

<?php
/**
* 2007-2015 PrestaShop
*
* NOTICE OF LICENSE
*
* This source file is subject to the Academic Free License (AFL 3.0)
* that is bundled with this package in the file LICENSE.txt.
* It is also available through the world-wide-web at this URL:
* http://opensource.org/licenses/afl-3.0.php
* If you did not receive a copy of the license and are unable to
* obtain it through the world-wide-web, please send an email
* to license@prestashop.com so we can send you a copy immediately.
*
* DISCLAIMER
*
* Do not edit or add to this file if you wish to upgrade PrestaShop to newer
* versions in the future. If you wish to customize PrestaShop for your
* needs please refer to http://www.prestashop.com for more information.
*
*  @author    PrestaShop SA <contact@prestashop.com>
*  @copyright 2007-2015 PrestaShop SA
*  @license   http://opensource.org/licenses/afl-3.0.php  Academic Free License (AFL 3.0)
*  International Registered Trademark & Property of PrestaShop SA
*/

include_once(dirname(__FILE__).'/../../config/config.inc.php');
include_once(_PS_MODULE_DIR_.'paypal/paypal.php');

/*
 * Instant payment notification class.
 * (wait for PayPal payment confirmation, then validate order)
 */
class PayPalIPN extends PayPal
{

	public function getIPNTransactionDetails($result)
	{
		if (is_array($result) || (strcmp(trim($result), "VERIFIED") === false))
		{
			$transaction_id = pSQL($result['txn_id']);
			
			return array(
				'id_transaction' => $transaction_id,
				'transaction_id' => $transaction_id,
				'id_invoice' => $result['invoice'],
				'currency' => pSQL($result['mc_currency']),
				'total_paid' => (float)$result['mc_gross'],
				'shipping' => (float)$result['mc_shipping'],
				'payment_date' => pSQL($result['payment_date']),
				'payment_status' => pSQL($result['payment_status']),
			);
		}
		else
		{
			$transaction_id = pSQL(Tools::getValue('txn_id'));
			
			return array(
				'id_transaction' => $transaction_id,
				'transaction_id' => $transaction_id,
				'id_invoice' => pSQL(Tools::getValue('invoice')),
				'currency' => pSQL(Tools::getValue('mc_currency')),
				'total_paid' => (float)Tools::getValue('mc_gross'),
				'shipping' => (float)Tools::getValue('mc_shipping'),
				'payment_date' => pSQL(Tools::getValue('payment_date')),
				'payment_status' => pSQL(Tools::getValue('payment_status')),
			);
		}
	}

	public function confirmOrder($custom)
	{
		$result = $this->getResult();

		$payment_status = Tools::getValue('payment_status');
		$mc_gross = Tools::getValue('mc_gross');
		$txn_id = Tools::getValue('txn_id');
		
		$id_order = (int)PayPalOrder::getIdOrderByTransactionId($txn_id);
		
		if ($id_order != 0)
			Context::getContext()->cart = new Cart((int)$id_order);
		elseif (isset($custom['id_cart']))
			Context::getContext()->cart = new Cart((int)$custom['id_cart']);
		
		$address = new Address((int)Context::getContext()->cart->id_address_invoice);
		Context::getContext()->country = new Country((int)$address->id_country);
		Context::getContext()->customer = new Customer((int)Context::getContext()->cart->id_customer);
		Context::getContext()->language = new Language((int)Context::getContext()->cart->id_lang);
		Context::getContext()->currency = new Currency((int)Context::getContext()->cart->id_currency);
		
		if (isset(Context::getContext()->cart->id_shop))
			Context::getContext()->shop = new Shop(Context::getContext()->cart->id_shop);
		
		if (strcmp(trim($result), "VERIFIED") === false)
		{
			$details = $this->getIPNTransactionDetails($result);
			
			if ($id_order != 0)
			{
				$history = new OrderHistory();
				$history->id_order = (int)$id_order;
				
				PayPalOrder::updateOrder($id_order, $details);
				$history->changeIdOrderState((int)Configuration::get('PS_OS_ERROR'), $history->id_order);
				
				$history->addWithemail();
				$history->save();
			}
		}
		elseif (strcmp(trim($result), "VERIFIED") === 0)
		{
			$details = $this->getIPNTransactionDetails($result);
			
			if (version_compare(_PS_VERSION_, '1.5', '<'))
				$shop = null;
			else
			{
				$shop_id = Context::getContext()->shop->id;
				$shop = new Shop($shop_id);
			}
			
			if ($id_order != 0)
			{
				$order = new Order((int)$id_order);
				$values = $this->checkPayment($payment_status, $mc_gross, false);
				
				if ((int)$order->current_state == (int)$values['payment_type'])
					return;
				
				$history = new OrderHistory();
				$history->id_order = (int)$id_order;
				
				PayPalOrder::updateOrder($id_order, $details);
				$history->changeIdOrderState($values['payment_type'], $history->id_order);
				
				$history->addWithemail();
				$history->save();
			}
			else
			{
				$values = $this->checkPayment($payment_status, $mc_gross, true);
				$customer = new Customer((int)Context::getContext()->cart->id_customer);
				$this->validateOrder(Context::getContext()->cart->id, $values['payment_type'], $values['total_price'], $this->displayName, $values['message'], $details, Context::getContext()->cart->id_currency, false, $customer->secure_key, $shop);
			}
		}
	}

	public function checkPayment($payment_status, $mc_gross_not_rounded, $new_order)
	{
		$currency_decimals = is_array(Context::getContext()->currency) ? (int)Context::getContext()->currency['decimals'] : (int)Context::getContext()->currency->decimals;
		$this->decimals = $currency_decimals * _PS_PRICE_DISPLAY_PRECISION_;
		
		$mc_gross = Tools::ps_round($mc_gross_not_rounded, $this->decimals);
		
		$cart_details = Context::getContext()->cart->getSummaryDetails(null, true);
		$cart_hash = sha1(serialize(Context::getContext()->cart->nbProducts()));
		$custom = Tools::jsonDecode(Tools::getValue('custom'), true);
		
		$shipping = $cart_details['total_shipping_tax_exc'];
		$subtotal = $cart_details['total_price_without_tax'] - $cart_details['total_shipping_tax_exc'];
		$tax = $cart_details['total_tax'];
		
		$total_price = Tools::ps_round($shipping + $subtotal + $tax, $this->decimals);
	
		if (($new_order == true) && ($this->comp($mc_gross, $total_price, 2) !== 0))
		{
			$payment_type = (int)Configuration::get('PS_OS_ERROR');
			$message = $this->l('Price paid on paypal is not the same that on PrestaShop.').'<br />';
		}
		elseif (($new_order == true) && ($custom['hash'] != $cart_hash))
		{
			$payment_type = (int)Configuration::get('PS_OS_ERROR');
			$message = $this->l('Cart changed, please retry.').'<br />';
		}
		else
		{
			return $this->getDetails($payment_status) + array(
				'payment_status' => $payment_status,
				'total_price' => $total_price
			);
		}
		
		return array(
			'message' => $message,
			'payment_type' => $payment_type,
			'payment_status' => $payment_status,
			'total_price' => $total_price
		);
	}
	
	public function getDetails($payment_status)
	{
		if ((bool)Configuration::get('PAYPAL_CAPTURE'))
		{
			$payment_type = (int)Configuration::get('PS_OS_WS_PAYMENT');
			$message = $this->l('Pending payment capture.').'<br />';
		}
		else
		{
			if (strcmp($payment_status, 'Completed') === 0)
			{
				$payment_type = (int)Configuration::get('PS_OS_PAYMENT');
				$message = $this->l('Payment accepted.').'<br />';
			}
			elseif (strcmp($payment_status, 'Pending') === 0)
			{
				$payment_type = (int)Configuration::get('PS_OS_PAYPAL');
				$message = $this->l('Pending payment confirmation.').'<br />';
			}
			else
			{
				$payment_type = (int)Configuration::get('PS_OS_ERROR');
				$message = $this->l('Cart changed, please retry.').'<br />';
			}
		}
		
		return array(
			'message' => $message,
			'payment_type' => (int)$payment_type
		);
	}

	public function getResult()
	{
		if ((int)Configuration::get('PAYPAL_SANDBOX') == 1)
			$action_url = 'https://www.sandbox.paypal.com/cgi-bin/webscr?cmd=_notify-validate';
		else
			$action_url = 'https://www.paypal.com/cgi-bin/webscr?cmd=_notify-validate';
		
		$request = '';
		foreach ($_POST as $key => $value) 
		{         
			$value = urlencode(Tools::stripslashes($value));  
			$request .= "&$key=$value";           
		}
		
		$handle = fopen(dirname(__FILE__).'/log.txt', 'w+');
		fwrite($handle, $action_url.$request);			
		return Tools::file_get_contents($action_url.$request);
	}

}

if (Tools::getIsset('custom'))
{
	$ipn = new PayPalIPN();
	$custom = Tools::jsonDecode(Tools::getValue('custom'), true);
	$ipn->confirmOrder($custom);
}