Magento 1 Bestsellers from Order Data (Not aggregated data)

magento.bestsellers.catalog.category.collection.php

/* Best Sellers Category */
$today = time();
$from = date('Y-m-d', strtotime("-12 months",$today));//pull best sellers from 12 months prior order data
$to = date("Y-m-d", $today);

$resource = Mage::getSingleton('core/resource');
$readConnection = $resource->getConnection('core_read');

$orderTableAliasName  = $readConnection->quoteIdentifier('order');

$orderJoinCondition   = array(
    $orderTableAliasName . '.entity_id = order_items.order_id',
    $readConnection->quoteInto("{$orderTableAliasName}.state <> ?", Mage_Sales_Model_Order::STATE_CANCELED),
);//ensure we don't count canceled orders.. we count refunds/returns tho, since the sale was actually made.

if ($from != '' && $to != '') {
    $fieldName            = $orderTableAliasName . '.created_at';
    $orderJoinCondition[] = sprintf('(%s BETWEEN %s AND %s)',
        $fieldName,
        $readConnection->quote($from),
        $readConnection->quote($to)
    );
}
$ids = [];
$parents = [];
$select = $readConnection->select()->reset()
    ->from(
        array('order_items' => $resource->getTableName('sales/order_item')),
        array(
            'ordered_qty' => 'SUM(order_items.qty_ordered)',
            'product_id' => 'order_items.product_id',
            'product_type',
            'name'
        ))
    ->joinInner(
        array('order' => $resource->getTableName('sales/order')),
        implode(' AND ', $orderJoinCondition),
        array())
    ->joinLeft(
        array('super' => $resource->getTableName('catalog/product_super_link')),
        'super.product_id = order_items.product_id',
        array('product_super_id' => 'super.parent_id')
    )
    ->where('order_items.parent_item_id IS NULL AND order_items.sku NOT LIKE ?','%GWP%')
    ->group('product_id')
    ->having('SUM(order_items.qty_ordered) > ?', 0)
    ->order('SUM(order_items.qty_ordered) DESC')
    ->limit(58);//i limit to 58 so I can pull a few extra just in case some get removed during lint
$results = $readConnection->fetchAll($select);
foreach($results as $row){
    $ids[] = $row['product_id'];
    if($row['product_super_id']){
        $parents[$row['product_id']] = $row['product_super_id']; //has parent
    }
}
$simples = array_diff($parents,$ids); //lint the simples if parents already included
$filteredIds = array_merge($ids,$simples); //merge all unique simples with rest of IDs into one array
/* we now have items that are not simples of any configs already pulled */
$collection = Mage::getResourceModel('catalog/product_collection')
    ->setStoreId($this->getStoreId())
    ->addAttributeToFilter('entity_id', array('in' => $filteredIds));
$collection->getSelect()->order(new Zend_Db_Expr('FIELD(e.entity_id, ' . implode(',', $filteredIds).')'));
$collection->getSelect()->limit(48);

return $collection;