private function sortByAlgorithm(array $indexes)
    {
        if (self::SORT_ALPHA === $this->configuration['sort_algorithm']) {
            uasort($indexes, [$this, 'sortAlphabetically']);
        } elseif (self::SORT_LENGTH === $this->configuration['sort_algorithm']) {
            uasort($indexes, [$this, 'sortByLength']);
        }

        return $indexes;
    }
private function sortByAlgorithm(array $indexes)
    {
        if (self::SORT_ALPHA === $this->configuration['sort_algorithm']) {
            uasort($indexes, [$this, 'sortAlphabetically']);
        } elseif (self::SORT_LENGTH === $this->configuration['sort_algorithm']) {
            uasort($indexes, [$this, 'sortByLength']);
        }

        return $indexes;
    }
@param array[] $indexes

@return array