public function setSkipHours(array $skipHours)
    {
        $skipHours = array_filter($skipHours, function ($hour) {
            return is_numeric($hour) && ($hour >= 0) && ($hour <= 23);
        });

        $skipHours = array_unique($skipHours);
        sort($skipHours);

        $this->skipHours = array_values($skipHours);

        return $this;
    }