woocommerce-auto-stock-restore.php

<?php
/**
 * Plugin Name: WooCommerce Auto Restore Stock
 * Plugin URI: http://gerhardpotgieter.com/tag/woocommerce-auto-restore-stock
 * Description: Auto restore stock when orders are cancelled
 * Version: 1.0.1
 * Author: Gerhard Potgieter
 * Author URI: http://gerhardpotgieter.cim
 * License: GPL2
 */

/*  Copyright 2013 Gerhard Potgieter  (email : potgieterg@gmail.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
*/

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

if ( ! class_exists( 'WC_Auto_Stock_Restore' ) ) {

	class WC_Auto_Stock_Restore {

		public function __construct() {
			add_action( 'woocommerce_order_status_processing_to_cancelled', array( $this, 'restore_order_stock' ), 10, 1 );
			add_action( 'woocommerce_order_status_completed_to_cancelled', array( $this, 'restore_order_stock' ), 10, 1 );
			add_action( 'woocommerce_order_status_on-hold_to_cancelled', array( $this, 'restore_order_stock' ), 10, 1 );
			add_action( 'woocommerce_order_status_processing_to_refunded', array( $this, 'restore_order_stock' ), 10, 1 );
			add_action( 'woocommerce_order_status_completed_to_refunded', array( $this, 'restore_order_stock' ), 10, 1 );
			add_action( 'woocommerce_order_status_on-hold_to_refunded', array( $this, 'restore_order_stock' ), 10, 1 );
		} // End __construct()

		public function restore_order_stock( $order_id ) {
			$order = new WC_Order( $order_id );

			if ( ! get_option('woocommerce_manage_stock') == 'yes' && ! sizeof( $order->get_items() ) > 0 ) {
				return;
			}

			foreach ( $order->get_items() as $item ) {

				if ( $item['product_id'] > 0 ) {
					$_product = $order->get_product_from_item( $item );

					if ( $_product && $_product->exists() && $_product->managing_stock() ) {

						$old_stock = $_product->stock;

						$qty = apply_filters( 'woocommerce_order_item_quantity', $item['qty'], $this, $item );

						$new_quantity = $_product->increase_stock( $qty );

						do_action( 'woocommerce_auto_stock_restored', $_product, $item );

						$order->add_order_note( sprintf( __( 'Item #%s stock incremented from %s to %s.', 'woocommerce' ), $item['product_id'], $old_stock, $new_quantity) );

						$order->send_stock_notifications( $_product, $new_quantity, $item['qty'] );
					}
				}
			}
		} // End restore_order_stock()
	}
	$GLOBALS['wc_auto_stock_restore'] = new WC_Auto_Stock_Restore();
}