protected function sortCalcDateCheck(\MUtil_Model_ModelAbstract $model)
    {
        $sort = $model->getSort();

        if (isset($sort['calc_used_date'])) {
            $add        = true;
            $resultSort = array();

            foreach ($sort as $key => $asc) {
                if ('calc_used_date' === $key) {
                    if ($add) {
                        $resultSort['is_completed']        = $asc;
                        $resultSort['gto_completion_time'] = $asc == SORT_ASC ? SORT_DESC : SORT_ASC;
                        $resultSort['calc_valid_from']     = $asc;
                        $add = false; // We can add this only once
                    }
                } else {
                    $resultSort[$key] = $asc;
                }
            }

            if (! $add) {
                $model->setSort($resultSort);
            }
        }
    }