<?php
/**
 * Magento
 *
 * NOTICE OF LICENSE
 *
 * This source file is subject to the Open Software License (OSL 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/osl-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@magentocommerce.com so we can send you a copy immediately.
 *
 * DISCLAIMER
 *
 * Do not edit or add to this file if you wish to upgrade Magento to newer
 * versions in the future. If you wish to customize Magento for your
 * needs please refer to http://www.magentocommerce.com for more information.
 *
 * @category    Mage
 * @package     Mage_Sales
 * @copyright   Copyright (c) 2010 Magento Inc. (http://www.magentocommerce.com)
 * @license     http://opensource.org/licenses/osl-3.0.php  Open Software License (OSL 3.0)
 */

class Mage_Sales_Model_Order_Shipment_Item extends Mage_Core_Model_Abstract
{
    protected $_eventPrefix = 'sales_shipment_item';
    protected $_eventObject = 'shipment_item';

    protected $_shipment = null;
    protected $_orderItem = null;

    /**
     * Initialize resource model
     */
    function _construct()
    {
        $this->_init('sales/order_shipment_item');
    }

    /**
     * Declare Shipment instance
     *
     * @param   Mage_Sales_Model_Order_Shipment $shipment
     * @return  Mage_Sales_Model_Order_Shipment_Item
     */
    public function setShipment(Mage_Sales_Model_Order_Shipment $shipment)
    {
        $this->_shipment = $shipment;
        return $this;
    }

    /**
     * Retrieve Shipment instance
     *
     * @return Mage_Sales_Model_Order_Shipment
     */
    public function getShipment()
    {
        return $this->_shipment;
    }

    /**
     * Declare order item instance
     *
     * @param   Mage_Sales_Model_Order_Item $item
     * @return  Mage_Sales_Model_Order_Shipment_Item
     */
    public function setOrderItem(Mage_Sales_Model_Order_Item $item)
    {
        $this->_orderItem = $item;
        $this->setOrderItemId($item->getId());
        return $this;
    }

    /**
     * Retrieve order item instance
     *
     * @return Mage_Sales_Model_Order_Item
     */
    public function getOrderItem()
    {
        if (is_null($this->_orderItem)) {
            if ($this->getShipment()) {
                $this->_orderItem = $this->getShipment()->getOrder()->getItemById($this->getOrderItemId());
            }
            else {
                $this->_orderItem = Mage::getModel('sales/order_item')
                    ->load($this->getOrderItemId());
            }
        }
        return $this->_orderItem;
    }

    /**
     * Declare qty
     *
     * @param   float $qty
     * @return  Mage_Sales_Model_Order_Invoice_Item
     */
    public function setQty($qty)
    {
        if ($this->getOrderItem()->getIsQtyDecimal()) {
            $qty = (float) $qty;
        }
        else {
            $qty = (int) $qty;
        }
        $qty = $qty > 0 ? $qty : 0;
        /**
         * Check qty availability
         */
        if ($qty <= $this->getOrderItem()->getQtyToShip() || $this->getOrderItem()->isDummy(true)) {
            $this->setData('qty', $qty);
        }
        else {
            Mage::throwException(
                Mage::helper('sales')->__('Invalid qty to ship for item "%s"', $this->getName())
            );
        }
        return $this;
    }

    /**
     * Applying qty to order item
     *
     * @return Mage_Sales_Model_Order_Shipment_Item
     */
    public function register()
    {
        $this->getOrderItem()->setQtyShipped(
            $this->getOrderItem()->getQtyShipped()+$this->getQty()
        );
        return $this;
    }

    /**
     * Before object save
     *
     * @return Mage_Sales_Model_Order_Shipment_Item
     */
    protected function _beforeSave()
    {
        parent::_beforeSave();

        if (!$this->getParentId() && $this->getShipment()) {
            $this->setParentId($this->getShipment()->getId());
        }

        return $this;
    }

}