EDD PayFast

<?php
/*
Plugin Name: EDD PayFast Payment Gateway
Plugin URI: http://www.mesaneweb,com
Description: Accept payments through PayFast for your Digital Store powered by Easy Digital Downloads, a payment gateway for South Africans.
Version: 1.0.1
Author: Dane A. Mesane
Author URI: http://www.mesaneweb.com
License: GPL version 2 or later - http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
*/
/*  Copyright 2014  Dane A. Mesane (www.mesaneweb.com)  ( email : support@mesaneweb.com )

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License, version 2, as
    published by the Free Software Foundation.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
*/

//check the existensi of our class and Easy_Digital_Downloads,
if( ! class_exists( 'EDD_Payfast' ) ) :

class EDD_Payfast {

	/**
	 * @var instance The one true EDD_Payfast class
	 * singleton
	 */
	private static $instance;

	// Our file of this plugin
	public $file;

	// Our plugin path
	public $plugin_path;

	// Our plugin url
	public $plugin_url;

	// the version of this plugin
	public $version;

	/**
	 * Main EDD_Payfast Instance
	 * singleton implementation
	 */
	public static function instance() {
		if ( ! isset( self::$instance ) ) {
			self::$instance = new EDD_Payfast(__FILE__);
		}
		return self::$instance;
	}
	/**
	 * Constructor
	 * @since  1.0.0
	 * @return  void
	 */
	private function __construct( $file ) {

		//set up our data
		$this->version = '1.0.0';
		$this->file = $file;
		$this->plugin_url = trailingslashit( plugins_url( '', $plugin = $file ) );
		$this->plugin_path = trailingslashit( dirname( $file ) );

		if ( ! function_exists( 'json_decode' ) ) {
			if ( is_admin() )
				add_action( 'admin_notices', array( &$this, 'initialization_warning' ) );
			return;
		}
		//hooks for admin
		if( is_admin() )
			add_filter( 'edd_settings_gateways', array( &$this, 'add_settings_gateways' ) );

		// hooks
		add_filter( 'edd_currencies', array( &$this, 'rand_currencies' )); //add South African  currency, R or ZAR
		add_filter( 'edd_accepted_payment_icons', array( &$this, 'payfast_payment_icon' ) );
		add_filter( 'edd_payment_gateways', array( &$this, 'register_gateway' ) );
		add_action( 'edd_payfast_cc_form', array( &$this, 'gateway_cc_form' ) );
        add_action( 'edd_gateway_payfast', array( &$this, 'process_payment' ) );
		add_action( 'init', array( &$this, 'validate_report_back' ) ); // trying to get notify from payfast
		add_action( 'edd_payfast_check', array( &$this, 'process_payfast_notify' ) );

	} //end __construct

	/**
	 * Yeah, Because we need json_docode() function to retrieve session ID from Payfast
	 * So if the function don't exists we should throw a warning
	 *
	 * @since 1.0
	 */
	public function initialization_warning() {
		echo '<div id="edd-payfast-warning" class="updated fade"><p><strong>' . sprintf( __( '%s PHP library not installed.', 'edd-payfast' ), 'JSON' ) . '</strong> ';
		echo sprintf( __('EDD Payfast Payment Gateway plugin will not function without <a href="%s">PHP JSON functions</a> enabled. Please update your version of WordPress for improved compatibility and/or enable native JSON support for PHP.'), 'http://php.net/manual/book.json.php' );
		echo '</p></div>';
	}

	/*	in order to disable credit card form that registered by Easy Digital Downloads by default. I return to blank value
	*	on other words, we just registered that. we don't need that for our gateway..
	*/
	public static function gateway_cc_form() {
        return;
	} //end gateway_cc_form()

	/*
	*	add our icon on checkout page
	*
	*	@return void
	*	@access public
	*
	*/

	public function payfast_payment_icon( $icons ) {
		$icons[$this->plugin_url . 'assets/images/PayFast.png'] = 'Payfast';
		return $icons;
	} //end payfast_payment_icon()

	/*
	*	add our currency, sadly South African Rand ( R ) not support on the core of Easy Digital Downloads
	*	but the plugin allow to filter that function
	*
	*	I don't know why other people called our currency is ZAR, but we familiar with R as our currency
	*	because of that, I set both here...
	*/
	function rand_currencies( $currencies ) {

		$currencies['R'] = __('South African Rand ( R )', 'edd_payfast');

		return $currencies;

	} //end rand_currencies()

	// Remote get and retrieve respon body..
    private function remote_get( $url, $headers = array() ) {

		$response = wp_remote_get( $url,
			array(
				'redirection' => 1,
				'httpversion' => '1.1',
				'user-agent'  => 'EDD Payfast' . $this->version . '; WordPress (' . home_url( '/' ) . ')',
				'timeout'     => 15,
				'headers'     => $headers
			)
		);

		if ( !is_wp_error( $response ) && $response['response']['code'] == 200 ) {
			return $response['body'];
		} else {
			return false;
		}
	} //end remote_get()

	// Lets register our gateway, we can use $gateways object because this run during hooks
	public function register_gateway( $gateways ) {

		$gateways['payfast'] = array( 'admin_label' => __( 'Payfast', 'edd_payfast' ), 'checkout_label' => __('Payfast', 'edd_payfast'));

		return $gateways;
	}

	/*
	* Easy Digital Downloads have settings method that allow other developer filter that to add additional settings
	* So because this plugin is an extension/add on for EDD, we don't need create settings from scratch or create
	* tradional setting on Wordpress, beautifull..
	*
	* @access public
	* @return void
	* @since 0.0.1
	*/
	public function add_settings_gateways( $settings ) {

		$edd_payfast_settings = array(

		array(
			'id' => '_edd_payfast_gateway_settings',
			'name' => '<strong>' . __('Payfast Gateway Settings', 'edd_payfast') . '</strong>',
			'desc' => __('Configure the gateway settings', 'edd_payfast'),
			'type' => 'header'
		),
		array(
			'id' => 'edd_payfast_merchant_id',
			'name' => __('Merchant ID', 'pw_edd'),
			'desc' => __('Enter your Payfast Merchant ID, you can finf it under settings in your PayFast account. Please click <a https://www.payfast.co.za/acc/integration>here</a>.', 'edd_payfast'),
			'type' => 'text',
			'size' => 'regular'
		),
		array(
			'id' => 'edd_payfast_merchant_key',
			'name' => __('Merchant Key', 'pw_edd'),
			'desc' => __('Enter your Payfast Merchant Key, you can finf it under settings in your PayFast account. Please click <a https://www.payfast.co.za/acc/integration >here</a>.', 'edd_payfast'),
			'type' => 'text',
			'size' => 'regular'
		)
	);

		return array_merge( $settings, $edd_payfast_settings );
	} //end add_settings_gateways()

	public function process_payment( $purchase_data ) {

		global $edd_options;

		// Check there is a gateway name
		if ( ! isset( $purchase_data['post_data']['edd-gateway'] ) )
    	return;

		$errors = edd_get_errors();

		if( !$errors ) {

			$payment_data = array(
				'price' => $purchase_data['price'],
				'date' => $purchase_data['date'],
				'user_email' => $purchase_data['user_email'],
				'purchase_key' => $purchase_data['purchase_key'],
				'currency' => $edd_options['currency'],
				'downloads' => $purchase_data['downloads'],
				'user_info' => $purchase_data['user_info'],
				'cart_details' => $purchase_data['cart_details'],
				'status' => 'pending'
			);

			// record the pending payment
			$payment = edd_insert_payment( $payment_data );

			if ( ! $payment ) {
				// Record the error
				edd_record_gateway_error( __( 'Payment Error', 'edd_payfast' ), sprintf( __( 'Payment creation failed before sending buyer to Payfast. Payment data: %s', 'edd_payfast' ), json_encode( $payment_data ) ), $payment );
				// Problems? send back
				edd_send_back_to_checkout( '?payment-mode=' . $purchase_data['post_data']['edd-gateway'] );

			} else {

				$return_url = add_query_arg( 'payment-confirmation', 'payfast', get_permalink( $edd_options['success_page'] ) );
				$listener_url = trailingslashit( home_url() ).'?payfast=notify';
				$cancel_url = add_query_arg( 'payment-cancel', 'payfast', edd_get_failed_transaction_uri() );

				$summary = edd_get_purchase_summary( $purchase_data, false );
				$quantity = edd_get_cart_quantity();

				function edd_get_payfast_redirect( $ssl_check = false ) {
    global $edd_options;
				if ( is_ssl() || ! $ssl_check) {
					$protocal = 'https://';
				} else {
					$protocal = 'http://';
				}

				if( edd_is_test_mode() ) {
					$url_to_send = $protocal . 'http://sandbox.payfast.co.za/eng/process';
				} else {
					$url_to_send = $protocal . 'http://www.payfast.co.za/eng/process';
				}

				$payfast_args = array(
					'key'      => $edd_options['edd_payfast_api_key'], // API Key Merchant / Penjual
					'action'   => 'payment',
					'product'  => stripslashes_deep( html_entity_decode( wp_strip_all_tags( $summary ), ENT_COMPAT, 'UTF-8' ) ),
					'price'    => round( $purchase_data['price'] - $purchase_data['tax'], 2 ), //
					'quantity' => $quantity,
					'comments' => $payment, // Optional for Payfast, but this is the payment ID, we need it to verify payment
					'ureturn'  => $return_url,
					'unotify'  => $listener_url,
					'ucancel'  => $cancel_url, //if cancel back to check out
					'format'   => 'json' // Format: xml / json. Default: xml
				);

				//var_dump( add_query_arg( $payfast_args, $url_to_send ) ); exit;
				$url_to_send .= http_build_query( $payfast_args );
				//remote get and retrieve a session id from payfast
                $response = $this->remote_get( $url_to_send );

				if ( $response == null || $response == 'null' )
					return false;

				$payfast = json_decode( $response );
				//get the session from payfast, we are ready to send the buyer
				$session_id = $payfast->sessionID;

				//save to database first, we will need it
				add_post_meta( $payment, '_payfast_session_id', $session_id );

				//get rid of cart contents
				edd_empty_cart();

				//build an query againt, but we just need session id
				$params = array( 'sessionID'	=> $session_id,  );
				$redirecting_to = add_query_arg( $params, 'https://www.payfast.co.za/' );
				//redirect to payfast
				wp_redirect( $redirecting_to );
				exit;

			 } //end statement payment


                } //end statement error
               else {
                        $fail = true; // errors were detected
                } //end statement

                if( $fail !== false ) {
                        // if errors are present, send the user back to the purchase page so they can be corrected
                        edd_send_back_to_checkout('?payment-mode=' . $purchase_data['post_data']['edd-gateway']);
                } //end statement

	} //end process_payment()

	public function validate_report_back() {
		global $edd_options;

		// Regular Payfast notify
		if ( isset( $_GET['payfast'] ) && $_GET['payfast'] == 'notify' ) {
			do_action( 'edd_payfast_check' );
		} //end statement
	} //end validate_report_back()

	/**
	 * Extract the site's host domain for referer notify from payfast.
	 *
	 * @since 1.0
	 * @param string $url URL to extract
	 * @return host of url that given on param, or false if failed extract url
	 * @access private
	 */
	public function check_referer_notify( $url ) {

		if ( ! ( is_string( $url ) && $url ) )
			return false;

		if ( ! function_exists('parse_url') )
			return false;

		// PHP 5.3.3 or newer can throw a warning
		try {
			if ( version_compare( PHP_VERSION, '5.1.2', '>=') ) {
				$ref = parse_url ( $url, PHP_URL_HOST );
			} else {
				$parse_ref = parse_url( $url );
				if ( $parse_ref !== false && isset( $parse_ref['host'] ) )
					$ref	= $parse_ref['host'];
			}
		} catch (Exception $e){}

		// Check $ref is not empty or null, is so return that.
		if( empty( $ref ) || $ref = null )
			return false;
		else
			return $ref;
	}

	/*
	* process_payfast_notify() function
	* process notify that send by payfast after we send the buyer on payment
	*
	* if buyer complete the payment, we need update the payment to complete too
	* @since 1.0
	*/
	public function process_payfast_notify() {

		global $edd_options;

		// Check the request method is POST
		if ( isset( $_SERVER['REQUEST_METHOD'] ) && $_SERVER['REQUEST_METHOD'] != 'POST' ) {
			return;
		} //end statement


		if ( isset( $_POST['status'] ) && isset( $_POST['trx_id'] ) && isset( $_POST['sid'] ) && isset( $_POST['product'] ) && isset( $_POST['quantity'] ) && isset( $_POST['total'] ) && isset( $_POST['comments'] ) ) {

			// setup each of the variables from payfast
			$payment_id = $_POST['comments'] ? $_POST['comments'] : null;
			$payfast_status = strtolower( $_POST['status'] ) ? strtolower( $_POST['status'] ) : null;
			$payfast_session = $_POST['sid'] ? $_POST['sid'] : null;
			$payfast_product = $_POST['product'] ? $_POST['product'] : null;
			$payfast_quantity = $_POST['quantity'] ? $_POST['quantity'] : null;
			$payfast_amount = $_POST['total'] ? $_POST['total'] : null;

			// retrieve the meta info for this payment
			$payment_meta 		= get_post_meta( $payment_id, '_edd_payment_meta', true );
			$payment_session	= get_post_meta( $payment_id, '_payfast_session_id', true );
			$payment_amount 	= edd_format_amount( $payment_meta['amount'] );


			// check url referrer..
			if( ! function_exists( 'wp_get_referer' ) )
				include_once( ABSPATH . 'wp-includes/functions.php' );
				$referer = wp_get_referer();
			if( empty( $referer ) )
				return;

			$ref = $this->check_referer_notify( $referer );
			if ( $ref != 'payfast.co.za' )
				return; // referrer from payfast? if not return that.

			if( get_post_status( $payment_id ) == 'complete' )
				return; // Only complete payments once

			if ( edd_get_payment_gateway( $payment_id ) != 'payfast' )
				return; // this isn't from payfast

			if( $payfast_amount != $payment_amount )
				return; // the prices don't match

			//	check the session id, this session is an unique key. generating by payfast
			// if this don't match, this is not from payfast or other payment
			if( $payfast_session != $payment_session )
				return;

			/* everything has been verified, update the payment to "complete"
			*  berhasil is Indonesian language that mean success.
			*/
			if( $payfast_status == 'berhasil' ) :
				edd_update_payment_status( $payment_id, 'publish' );
				delete_post_meta( $payment_id, '_payfast_session_id', $payment_session );
			endif;


		}//end statement

	} //end process_payfast_notify()


} // end EDD_Payfast Class
endif; // end check

/**
 * Throw an error if Easy Digital Download is not installed.
 *
 * @since 0.2
 */
function syaiful_payfast_missing_error_edd() {
	echo '<div class="error"><p>' . sprintf( __( 'Please %sinstall &amp; activate Easy Digital Downloads%s to allow this plugin to work.' ), '<a href="' . admin_url( 'plugin-install.php?tab=search&type=term&s=easy+digital+downloads&plugin-search-input=Search+Plugins' ) . '">', '</a>' ) . '</p></div>';
} // end syaiful_payfast_missing_error_edd()

// Throw an error if Wordpress version is below 3.4
function syaiful_missing_error_wordpress_version() {
	echo '<div class="error"><p>' . __( 'Please upgrade WordPress to the latest version to allow WordPress and this plugin to work properly.', 'edd_payfast' ) . '</p></div>';
} // end syaiful_missing_error_wordpress_version()

// the instance of our plugin,
function edd_payfast() {
	return EDD_Payfast::instance();
}

// Loader function for the plugin
function syaiful_edd_payfast_init() {
	global $wp_version;

	if ( !version_compare( $wp_version, '3.4', '>=' ) ) {
		add_action( 'all_admin_notices', 'syaiful_missing_error_wordpress_version' );
	} else if ( class_exists( 'Easy_Digital_Downloads') ) {
			edd_payfast(); //load our plugin
		} else {
			add_action( 'all_admin_notices', 'syaiful_payfast_missing_error_edd' );
		}
} // end syaiful_edd_payfast_init()

// tap... tap .... hi Wordpress, load our plugin please...
add_action( 'plugins_loaded', 'syaiful_edd_payfast_init', 20 ); //lower because waiting Easy Digital Downloads running..