/**
    * @param string|array<int|string>|null $value
     *
     * @return string|array<int|string>|null
     */
    public function transform($value) {
        if ($value !== null && !is_array($value) && $value != -1) {
            $transformed = [
                'year'  => gmdate('Y', (int) $value),
                'month' => gmdate('n', (int) $value),
            ];
        } elseif ($value == -1) {
            $transformed = [
                'year'  => -1,
                'month' => -1,
            ];
        } else {
            $transformed = $value;
        }

        return $transformed;
    }