/app/code/core/Mage/Catalog/Model/Resource/Product/Link/Product/Collection.php

<?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_Catalog

 * @copyright   Copyright (c) 2012 Magento Inc. (http://www.magentocommerce.com)

 * @license     http://opensource.org/licenses/osl-3.0.php  Open Software License (OSL 3.0)

 */





/**

 * Catalog product linked products collection

 *

 * @category    Mage

 * @package     Mage_Catalog

 * @author      Magento Core Team <core@magentocommerce.com>

 */

class Mage_Catalog_Model_Resource_Product_Link_Product_Collection extends Mage_Catalog_Model_Resource_Product_Collection

{

    /**

     * Store product model

     *

     * @var Mage_Catalog_Model_Product

     */

    protected $_product;



    /**

     * Store product link model

     *

     * @var Mage_Catalog_Model_Product_Link

     */

    protected $_linkModel;



    /**

     * Store link type id

     *

     * @var int

     */

    protected $_linkTypeId;



    /**

     * Store strong mode flag that determine if needed for inner join or left join of linked products

     *

     * @var bool

     */

    protected $_isStrongMode;



    /**

     * Store flag that determine if product filter was enabled

     *

     * @var bool

     */

    protected $_hasLinkFilter  = false;



    /**

     * Declare link model and initialize type attributes join

     *

     * @param Mage_Catalog_Model_Product_Link $linkModel

     * @return Mage_Catalog_Model_Resource_Product_Link_Product_Collection

     */

    public function setLinkModel(Mage_Catalog_Model_Product_Link $linkModel)

    {

        $this->_linkModel = $linkModel;

        if ($linkModel->getLinkTypeId()) {

            $this->_linkTypeId = $linkModel->getLinkTypeId();

        }

        return $this;

    }



    /**

     * Enable strong mode for inner join of linked products

     *

     * @return Mage_Catalog_Model_Resource_Product_Link_Product_Collection

     */

    public function setIsStrongMode()

    {

        $this->_isStrongMode = true;

        return $this;

    }



    /**

     * Retrieve collection link model

     *

     * @return Mage_Catalog_Model_Product_Link

     */

    public function getLinkModel()

    {

        return $this->_linkModel;

    }



    /**

     * Initialize collection parent product and add limitation join

     *

     * @param Mage_Catalog_Model_Product $product

     * @return Mage_Catalog_Model_Resource_Product_Link_Product_Collection

     */

    public function setProduct(Mage_Catalog_Model_Product $product)

    {

        $this->_product = $product;

        if ($product && $product->getId()) {

            $this->_hasLinkFilter = true;

        }

        return $this;

    }



    /**

     * Retrieve collection base product object

     *

     * @return Mage_Catalog_Model_Product

     */

    public function getProduct()

    {

        return $this->_product;

    }



    /**

     * Exclude products from filter

     *

     * @param array $products

     * @return Mage_Catalog_Model_Resource_Product_Link_Product_Collection

     */

    public function addExcludeProductFilter($products)

    {

        if (!empty($products)) {

            if (!is_array($products)) {

                $products = array($products);

            }

            $this->_hasLinkFilter = true;

            $this->getSelect()->where('links.linked_product_id NOT IN (?)', $products);

        }

        return $this;

    }



    /**

     * Add products to filter

     *

     * @param array|int|string $products

     * @return Mage_Catalog_Model_Resource_Product_Link_Product_Collection

     */

    public function addProductFilter($products)

    {

        if (!empty($products)) {

            if (!is_array($products)) {

                $products = array($products);

            }

            $this->getSelect()->where('links.product_id IN (?)', $products);

            $this->_hasLinkFilter = true;

        }



        return $this;

    }



    /**

     * Add random sorting order

     *

     * @return Mage_Catalog_Model_Resource_Product_Link_Product_Collection

     */

    public function setRandomOrder()

    {

        $this->getSelect()->orderRand('main_table.entity_id');

        return $this;

    }



    /**

     * Setting group by to exclude duplications in collection

     *

     * @param string $groupBy

     * @return Mage_Catalog_Model_Resource_Product_Link_Product_Collection

     */

    public function setGroupBy($groupBy = 'e.entity_id')

    {

        $this->getSelect()->group($groupBy);



        /*

         * Allow Analytic functions usage

         */

        $this->_useAnalyticFunction = true;



        return $this;

    }



    /**

     * Join linked products when specified link model

     *

     * @return Mage_Catalog_Model_Resource_Product_Link_Product_Collection

     */

    protected function _beforeLoad()

    {

        if ($this->getLinkModel()) {

            $this->_joinLinks();

        }

        return parent::_beforeLoad();

    }



    /**

     * Join linked products and their attributes

     *

     * @return Mage_Catalog_Model_Resource_Product_Link_Product_Collection

     */

    protected function _joinLinks()

    {

        $select  = $this->getSelect();

        $adapter = $select->getAdapter();



        $joinCondition = array(

            'links.linked_product_id = e.entity_id',

            $adapter->quoteInto('links.link_type_id = ?', $this->_linkTypeId)

        );

        $joinType = 'join';

        if ($this->getProduct() && $this->getProduct()->getId()) {

            $productId = $this->getProduct()->getId();

            if ($this->_isStrongMode) {

                $this->getSelect()->where('links.product_id = ?', (int)$productId);

            } else {

                $joinType = 'joinLeft';

                $joinCondition[] = $adapter->quoteInto('links.product_id = ?', $productId);

            }

            $this->addFieldToFilter('entity_id', array('neq' => $productId));

        } else if ($this->_isStrongMode) {

            $this->addFieldToFilter('entity_id', array('eq' => -1));

        }

        if($this->_hasLinkFilter) {

            $select->$joinType(

                array('links' => $this->getTable('catalog/product_link')),

                implode(' AND ', $joinCondition),

                array('link_id')

            );

            $this->joinAttributes();

        }

        return $this;

    }







    /**

     * Enable sorting products by its position

     *

     * @param string $dir sort type asc|desc

     * @return Mage_Catalog_Model_Resource_Product_Link_Product_Collection

     */

    public function setPositionOrder($dir = self::SORT_ORDER_ASC)

    {

        if ($this->_hasLinkFilter) {

            $this->getSelect()->order('position ' . $dir);

        }

        return $this;

    }



    /**

     * Enable sorting products by its attribute set name

     *

     * @param string $dir sort type asc|desc

     * @return Mage_Catalog_Model_Resource_Product_Link_Product_Collection

     */

    public function setAttributeSetIdOrder($dir = self::SORT_ORDER_ASC)

    {

        $this->getSelect()

            ->joinLeft(

                array('set' => $this->getTable('eav/attribute_set')),

                'e.attribute_set_id = set.attribute_set_id',

                array('attribute_set_name')

            )

            ->order('set.attribute_set_name ' . $dir);

        return $this;

    }



    /**

     * Join attributes

     *

     * @return Mage_Catalog_Model_Resource_Product_Link_Product_Collection

     */

    public function joinAttributes()

    {

        if (!$this->getLinkModel()) {

            return $this;

        }

        $attributes = $this->getLinkModel()->getAttributes();



        $attributesByType = array();

        foreach ($attributes as $attribute) {

            $table = $this->getLinkModel()->getAttributeTypeTable($attribute['type']);

            $alias = sprintf('link_attribute_%s_%s', $attribute['code'], $attribute['type']);



            $joinCondiotion = array(

                "{$alias}.link_id = links.link_id",

                $this->getSelect()->getAdapter()->quoteInto("{$alias}.product_link_attribute_id = ?", $attribute['id'])

            );

            $this->getSelect()->joinLeft(

                array($alias => $table),

                implode(' AND ', $joinCondiotion),

                array($attribute['code'] => 'value')

            );

        }



        return $this;

    }



    /**

     * Set sorting order

     *

     * $attribute can also be an array of attributes

     *

     * @param string|array $attribute

     * @param string $dir

     * @return Mage_Catalog_Model_Resource_Product_Link_Product_Collection

     */

    public function setOrder($attribute, $dir = self::SORT_ORDER_ASC)

    {

        if ($attribute == 'position') {

            return $this->setPositionOrder($dir);

        } elseif ($attribute == 'attribute_set_id') {

            return $this->setAttributeSetIdOrder($dir);

        }

        return parent::setOrder($attribute, $dir);

    }

}