list.php

<?php


class SNQ_Catalog_Helper_Catalog_Product_List extends SNQ_Catalog_Helper_Data
{
    const SALE_AMOUNT_SORT_FIELD = 'sale_amount';
    const DEFAULT_SORT_FIELD = 'position';

    /**
     * @param Mage_Catalog_Model_Resource_Product_Collection $collection
     * @param string $currentOrder
     * @param string $currentDirection
     */
    public function prepareCollectionSort($collection, $currentOrder, $currentDirection)
    {
        $select = $collection->getSelect();
        $this->_addColumns($collection);
        $this->_setCurrentOrder($select, $currentOrder, $currentDirection);
    }

    /**
     * @param Varien_Db_Select $select
     */
    protected function _addColumns($collection)
    {
        $select = $collection->getSelect();
        $select->columns(
            sprintf('(`price_index`.`final_price`-`price_index`.`price`) as %s', self::SALE_AMOUNT_SORT_FIELD));

        /*$attrTableAlias = 'product_attributes';
        if ($collection->isEnabledFlat()) {
            $attrTableAlias = 'e';
        }

        $select->columns(
            sprintf("-( IF(FIND_IN_SET(`%s`.`product_collection`,('%s')), 1, 0) * 10 + `at_stock_status1`.`stock_status` ) as %s",
                $attrTableAlias,
                implode(",", $this->_getNewArrivalsCollections()),
                self::NEW_ARRIVAL_SORT_FIELD
            )
        );*/
    }

    /**
     * @param Varien_Db_Select $select
     * @param string $currentOrder
     * @param string $currentDirection
     */
    protected function _setCurrentOrder($select, $currentOrder, $currentDirection)
    {
        if($currentOrder == self::SALE_AMOUNT_SORT_FIELD){
            $select->order(sprintf('%s %s', $currentOrder, $currentDirection));
        }elseif($currentOrder == self::DEFAULT_SORT_FIELD){

            //return $this->_getProductCollection();
            $productCollectionHelper = Mage::helper('snq_catalog/product_collection');
            $activeCollectionNames = $productCollectionHelper->getActiveCollections();

            $collections = array_map(function ($activeCollectionName){
                return "'" . $activeCollectionName . "'";
            }, $activeCollectionNames);

            if (!empty($_SERVER['HTTP_X_REQUESTED_WITH']) && strtolower($_SERVER['HTTP_X_REQUESTED_WITH']) == 'xmlhttprequest') {
                $select->reset('order')
                    ->joinLeft(
                        ['ps' => 'catalog_product_entity_varchar'],
                        'ps.attribute_id = 177 AND ps.entity_id = e.entity_id',
                        ['product_collection' => 'ps.value']
                    )
                    ->joinLeft(
                        ['pr' => 'catalog_product_entity_varchar'],
                        'pr.attribute_id = 230 AND pr.entity_id = e.entity_id',
                        ['price_rule' => 'pr.value']
                    )
                    ->order('IF(product_collection IN ('.implode(',' ,$collections).'), 0, 1) '.$currentDirection.', price_rule '.$currentDirection);
            } else {
                $select
                    ->reset('order')
                    ->order('IF(e.product_collection IN ('.implode(',' ,$collections).'), 0, 1) '.$currentDirection.', e.price_rule '.$currentDirection);
            }
        }

        /*elseif($currentOrder == self::DEFAULT_SORT_FIELD && strtolower($currentDirection) == 'desc'){
            $category = Mage::registry('current_category');
            if($category && in_array('59', $category->getPathIds())) {
                $select->reset('order')
                    ->order(['stock_status DESC', 'price_index.min_price DESC']);
            }
        }*/
    }


    /**
     * Get new arrivals collections
     * @return array|mixed
     */
    protected function _getNewArrivalsCollections()
    {
        /** @var SNQ_Sync_Helper_Data $helper */
        $helper = Mage::helper('snq_sync');
        return $helper->getSaleLastCollections();
    }

}