GT-Volk / working-time

     */

    public function nextWorkingDay(string $date = null) : string

    {

        if ($date === null) {

            $dateTime = new \DateTime($this->dateTime->format('Y-m-d'));

        } else {

            $dateTime = new \DateTime($date);

        }

        do {

            $dateTime->modify('+1 day');

     */

    public function nextWorkingTime(string $date = null) : string

    {

        if ($date === null) {

            $dateTime = new \DateTime($this->dateTime->format('Y-m-d H:i'));

        } else {

            $dateTime = new \DateTime($date);

        }

        $nextWorkingTime = '';

     */

    public function modify(int $minutes, string $date = null) : string

    {

        if ($date === null) {

            $dateTime = new \DateTime($this->dateTime->format('Y-m-d H:i'));

        } else {

            $dateTime = new \DateTime($date);

        }

        $nextWorkingTime = $this->nextWorkingTime($dateTime->format('Y-m-d H:i'));