<?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_Checkout
 * @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_Checkout_Model_Mysql4_Cart extends Mage_Core_Model_Mysql4_Abstract
{
    protected function _construct()
    {
        $this->_init('sales/quote', 'entity_id');
    }

    public function getItemsQty($cart)
    {
        return $this->fetchItemsSummaryQty($cart->getQuote()->getId());
    }

    public function fetchItemsSummaryQty($quoteId)
    {
        $entityType = Mage::getSingleton('eav/config')->getEntityType('quote_item');
        $attribute  = Mage::getSingleton('eav/config')->getAttribute($entityType->getEntityTypeId(), 'qty');

        $qtyAttributeTable = $this->getMainTable().'_'.$attribute->getBackendType();
        $read = $this->_getReadAdapter();
        $select = $read->select()
            ->from(array('qty'=>$qtyAttributeTable), 'sum(qty.value)')
            ->join(array('e'=>$this->getMainTable()), 'e.entity_id=qty.entity_id', array())
            ->where('e.parent_id=?', $quoteId)
            ->where('qty.entity_type_id=?', $entityType->getEntityTypeId())
            ->where('qty.attribute_id=?', $attribute->getAttributeId());
        $qty = $read->fetchOne($select);
        return $qty;
    }

    public function fetchItemsSummary($quoteId)
    {
        $read = $this->_getReadAdapter();
        $select = $read->select()
            ->from(array('q'=>$this->getTable('sales/quote')), array('items_qty', 'items_count'))
            ->where('q.entity_id=?', $quoteId);

        $result = $read->fetchRow($select);
        return $result ? $result : array('items_qty'=>0, 'items_count'=>0);
    }

    public function fetchItems($quoteId)
    {
        $read = $this->_getReadAdapter();
        $select = $read->select()
            ->from(array('qi'=>$this->getTable('sales/quote_item')), array('id'=>'item_id', 'product_id', 'super_product_id', 'qty', 'created_at'))
            ->where('qi.quote_id=?', $quoteId);

        return $read->fetchAll($select);
    }

    /**
     * Make collection not to load products that are in specified quote
     *
     * @param Mage_Catalog_Model_Resource_Eav_Mysql4_Product_Collection $collection
     * @param int $quoteId
     */
    public function addExcludeProductFilter($collection, $quoteId) {
        $collection->getSelect()->where(new Zend_Db_Expr(sprintf(
            'e.entity_id NOT IN (SELECT product_id FROM %s WHERE quote_id=%d)',
            $this->getTable('sales/quote_item'), $quoteId
        )));
    }
}