public static function shiftToTimezone(BusinessHours $businessHours, \DateTimeZone $newTimezone): BusinessHours
    {
        $now = new \DateTime('now');
        $oldTimezone = $businessHours->getTimezone();
        $offset = $newTimezone->getOffset($now) - $oldTimezone->getOffset($now);

        if ($offset === 0) {
            return clone $businessHours;
        }

        $tmpDays = \array_fill_keys(Day::getDaysOfWeek(), []);
        foreach ($businessHours->getDays() as $day) {
            foreach ($day->getOpeningHoursIntervals() as $interval) {
                $start = $interval->getStart()->toSeconds() + $offset;
                $end = $interval->getEnd()->toSeconds() + $offset;

                // Current day.
                if ($start < 86400 && $end > 0) {
                    $startForCurrentDay = \max($start, 0);
                    $endForCurrentDay = \min($end, 86400);

                    $dayOfWeek = $day->getDayOfWeek();
                    $interval = new TimeInterval(
                        TimeBuilder::fromSeconds($startForCurrentDay),
                        TimeBuilder::fromSeconds($endForCurrentDay)
                    );
                    $tmpDays[$dayOfWeek][] = $interval;
                }

                // Previous day.
                if ($start < 0) {
                    $startForPreviousDay = 86400 + $start;
                    $endForPreviousDay = \min(86400, 86400 + $end);

                    $dayOfWeek = self::getPreviousDayOfWeek($day->getDayOfWeek());
                    $interval = new TimeInterval(
                        TimeBuilder::fromSeconds($startForPreviousDay),
                        TimeBuilder::fromSeconds($endForPreviousDay)
                    );
                    $tmpDays[$dayOfWeek][] = $interval;
                }

                // Next day.
                if ($end > 86400) {
                    $startForNextDay = \max(0, $start - 86400);
                    $endForNextDay = $end - 86400;

                    $dayOfWeek = self::getNextDayOfWeek($day->getDayOfWeek());
                    $interval = new TimeInterval(
                        TimeBuilder::fromSeconds($startForNextDay),
                        TimeBuilder::fromSeconds($endForNextDay)
                    );
                    $tmpDays[$dayOfWeek][] = $interval;
                }
            }
        }

        $tmpDays = \array_filter($tmpDays);
        $days = self::flattenDaysIntervals($tmpDays);

        return new BusinessHours($days, $newTimezone);
    }