<?php
/**
 * Copyright © Magento, Inc. All rights reserved.
 * See COPYING.txt for license details.
 */

namespace Magento\CatalogInventory\Observer;

use Magento\CatalogInventory\Api\StockManagementInterface;
use Magento\CatalogInventory\Model\Configuration;
use Magento\Framework\Event\Observer as EventObserver;
use Magento\Framework\Event\ObserverInterface;

/**
 * Catalog inventory module observer
 */
class CancelOrderItemObserver implements ObserverInterface
{
    /**
     * @var \Magento\CatalogInventory\Model\Configuration
     */
    protected $configuration;

    /**
     * @var StockManagementInterface
     */
    protected $stockManagement;

    /**
     * @var \Magento\Catalog\Model\Indexer\Product\Price\Processor
     */
    protected $priceIndexer;

    /**
     * @param Configuration $configuration
     * @param StockManagementInterface $stockManagement
     * @param \Magento\Catalog\Model\Indexer\Product\Price\Processor $priceIndexer
     */
    public function __construct(
        Configuration $configuration,
        StockManagementInterface $stockManagement,
        \Magento\Catalog\Model\Indexer\Product\Price\Processor $priceIndexer
    ) {
        $this->configuration = $configuration;
        $this->stockManagement = $stockManagement;
        $this->priceIndexer = $priceIndexer;
    }

    /**
     * Cancel order item
     *
     * @param   EventObserver $observer
     * @return  void
     */
    public function execute(EventObserver $observer)
    {
        /** @var \Magento\Sales\Model\Order\Item $item */
        $item = $observer->getEvent()->getItem();
        $children = $item->getChildrenItems();
        $qty = $item->getQtyOrdered() - max($item->getQtyShipped(), $item->getQtyInvoiced()) - $item->getQtyCanceled();
        if ($item->getId() && $item->getProductId() && empty($children) && $qty && $this->configuration
            ->getCanBackInStock()) {
            $this->stockManagement->backItemQty($item->getProductId(), $qty, $item->getStore()->getWebsiteId());
        }
        $this->priceIndexer->reindexRow($item->getProductId());
    }
}