woocommerce-session-extend.php

<?php
/**
* Plugin Name: WooCommerce Session Extend
* Plugin URI: github.com
* Description: This plugin simply extends your cart sessions so users can keep their cart items for up to 30 days
* Version: 1.0
* Author: Dwain Maralack
* Author URI: http://dwainm.com
* Requires at least 3.8
*/

if ( ! defined( 'ABSPATH' ) ) exit; // Exit if accessed directly


add_action('plugins_loaded', 'load_woocommerce_session_extend_class');

//if ( ! class_exists( 'WooCommerce' ) ) exit; // exit if woocommerce is not installed
function load_woocommerce_session_extend_class(){

	add_filter('woocommerce_session_handler', 'replace_with_custom_session_handler_class');


	

	function replace_with_custom_session_handler_class(){
		return 'WC_Custom_Session_Extend_Handler';
	}

	/**
 * Custom WooCommerce class to Handle data for the current customers session, with the purpose of extending it
 * to 30 Days. 
 *
 * Implements the WC_Session abstract class
 *
 * Long term plan will be, if https://github.com/ericmann/wp-session-manager/ gains traction
 * in WP core, this will be switched out to use it and maintain backwards compatibility :)
 *
 * Partly based on WP SESSION by Eric Mann.
 *
 * @class 		WC_Session_Handler
 * @version		2.0.0
 * @package		WooCommerce/Classes
 * @category	Class
 * @author 		WooThemes
 */
if( class_exists('WC_Session') ){  // check if WooCommerce is alive

	class WC_Custom_Session_Extend_Handler extends WC_Session {

		/** cookie name */
		private $_cookie;

		/** session due to expire timestamp */
		private $_session_expiring;

		/** session expiration timestamp */
		private $_session_expiration;

		/** Bool based on whether a cookie exists **/
		private $_has_cookie = false;

		/**
		 * Constructor for the session class.
		 *
		 * @access public
		 * @return void
		 */
		public function __construct() {
			$this->_cookie = 'wp_woocommerce_session_' . COOKIEHASH;

			if ( $cookie = $this->get_session_cookie() ) {
				$this->_customer_id        = $cookie[0];
				$this->_session_expiration = $cookie[1];
				$this->_session_expiring   = $cookie[2];
				$this->_has_cookie         = true;

				// Update session if its close to expiring
				if ( time() > $this->_session_expiring ) {
					$this->set_session_expiration();
					$session_expiry_option = '_wc_session_expires_' . $this->_customer_id;
					// Check if option exists first to avoid auloading cleaned up sessions
					if ( false === get_option( $session_expiry_option ) ) {
						add_option( $session_expiry_option, $this->_session_expiration, '', 'no' );
					} else {
						update_option( $session_expiry_option, $this->_session_expiration );
					}
				}

			} else {
				$this->set_session_expiration();
				$this->_customer_id = $this->generate_customer_id();
			}

			$this->_data = $this->get_session_data();

	    	// Actions
	    	add_action( 'woocommerce_set_cart_cookies', array( $this, 'set_customer_session_cookie' ), 10 );
	    	add_action( 'woocommerce_cleanup_sessions', array( $this, 'cleanup_sessions' ), 10 );
	    	add_action( 'shutdown', array( $this, 'save_data' ), 20 );
	    }

	    /**
	     * Sets the session cookie on-demand (usually after adding an item to the cart).
	     *
	     * Since the cookie name (as of 2.1) is prepended with wp, cache systems like batcache will not cache pages when set.
	     *
	     * Warning: Cookies will only be set if this is called before the headers are sent.
	     */
	    public function set_customer_session_cookie( $set ) {
	    	if ( $set ) {
		    	// Set/renew our cookie
				$to_hash           = $this->_customer_id . $this->_session_expiration;
				$cookie_hash       = hash_hmac( 'md5', $to_hash, wp_hash( $to_hash ) );
				$cookie_value      = $this->_customer_id . '||' . $this->_session_expiration . '||' . $this->_session_expiring . '||' . $cookie_hash;
				$this->_has_cookie = true;

		    	// Set the cookie
		    	wc_setcookie( $this->_cookie, $cookie_value, $this->_session_expiration, apply_filters( 'wc_session_use_secure_cookie', false ) );
		    }
	    }

	    /**
	     * Return true if the current user has an active session, i.e. a cookie to retrieve values
	     * @return boolean
	     */
	    public function has_session() {
	    	return isset( $_COOKIE[ $this->_cookie ] ) || $this->_has_cookie || is_user_logged_in();
	    }

	    /**
	     * set_session_expiration function.
	     *
	     * @access public
	     * @return void
	     */
	    public function set_session_expiration() {
		    $this->_session_expiring    = time() + intval( apply_filters( 'wc_session_expiring', 60 * 60 * 719 ) ); // 30 Days
			$this->_session_expiration  = time() + intval( apply_filters( 'wc_session_expiration', 60 * 60 * 720 ) ); // 30 days Hours
	    }

		/**
		 * generate_customer_id function.
		 *
		 * @access public
		 * @return mixed
		 */
		public function generate_customer_id() {
			if ( is_user_logged_in() ) {
				return get_current_user_id();
			} else {
				return wp_generate_password( 32, false );
			}
		}

		/**
		 * get_session_cookie function.
		 *
		 * @access public
		 * @return mixed
		 */
		public function get_session_cookie() {
			if ( empty( $_COOKIE[ $this->_cookie ] ) ) {
				return false;
			}

			list( $customer_id, $session_expiration, $session_expiring, $cookie_hash ) = explode( '||', $_COOKIE[ $this->_cookie ] );

			// Validate hash
			$to_hash = $customer_id . $session_expiration;
			$hash    = hash_hmac( 'md5', $to_hash, wp_hash( $to_hash ) );

			if ( $hash != $cookie_hash ) {
				return false;
			}

			return array( $customer_id, $session_expiration, $session_expiring, $cookie_hash );
		}

		/**
		 * get_session_data function.
		 *
		 * @access public
		 * @return array
		 */
		public function get_session_data() {
			return (array) get_option( '_wc_session_' . $this->_customer_id, array() );
		}

	    /**
	     * save_data function.
	     *
	     * @access public
	     * @return void
	     */
	    public function save_data() {
	    	// Dirty if something changed - prevents saving nothing new
	    	if ( $this->_dirty && $this->has_session() ) {

				$session_option        = '_wc_session_' . $this->_customer_id;
				$session_expiry_option = '_wc_session_expires_' . $this->_customer_id;

		    	if ( false === get_option( $session_option ) ) {
		    		add_option( $session_option, $this->_data, '', 'no' );
			    	add_option( $session_expiry_option, $this->_session_expiration, '', 'no' );
		    	} else {
			    	update_option( $session_option, $this->_data );
		    	}
		    }
	    }

	    /**
		 * cleanup_sessions function.
		 *
		 * @access public
		 * @return void
		 */
		public function cleanup_sessions() {
			global $wpdb;

			if ( ! defined( 'WP_SETUP_CONFIG' ) && ! defined( 'WP_INSTALLING' ) ) {
				$now                = time();
				$expired_sessions   = array();
				$wc_session_expires = $wpdb->get_results( "SELECT option_name, option_value FROM $wpdb->options WHERE option_name LIKE '_wc_session_expires_%'" );

				foreach ( $wc_session_expires as $wc_session_expire ) {
					if ( $now > intval( $wc_session_expire->option_value ) ) {
						$session_id         = substr( $wc_session_expire->option_name, 20 );
						$expired_sessions[] = $wc_session_expire->option_name;  // Expires key
						$expired_sessions[] = "_wc_session_$session_id"; // Session key
					}
				}

				if ( ! empty( $expired_sessions ) ) {
					$expired_sessions_chunked = array_chunk( $expired_sessions, 100 );
					foreach ( $expired_sessions_chunked as $chunk ) {
						$option_names = implode( "','", $chunk );
						$wpdb->query( "DELETE FROM $wpdb->options WHERE option_name IN ('$option_names')" );
					}
				}
			}
		}
	}// end  class WC_Custom_Session_Extend_Handler
	
}// end WooCommerce class exists check


}// load_woocommerce_session_extend_class