public List<FreeScheduleItem> createFreeScheduleItemsByDate(Integer scheduleRuleId, LocalDate date, Integer duration) {
        if (finishWorkingTime == null) {
            return Arrays.asList(new FreeScheduleItem(scheduleRuleId, date, startWorkingTime, duration));
        }
        return Stream.iterate(startWorkingTime, startOfItem -> startOfItem.plusMinutes(duration))
                .limit((long)Math.ceil(ChronoUnit.MINUTES.between(startWorkingTime, finishWorkingTime) / duration.doubleValue()))
                .map(startOfItem -> new FreeScheduleItem(scheduleRuleId, date, startOfItem, duration))
                .collect(Collectors.toList());
    }

    public List<FreeScheduleItem> createFreeScheduleItemsByDateOld(Integer scheduleRuleId, LocalDate date, Integer duration) {
        if (finishWorkingTime == null) {
            return Arrays.asList(new FreeScheduleItem(scheduleRuleId, date, startWorkingTime, duration));
        }
        List<FreeScheduleItem> freeScheduleItems = new ArrayList<>();
        for (LocalTime startOfItem = startWorkingTime; startOfItem.isBefore(finishWorkingTime); startOfItem = startOfItem.plusMinutes(duration)) {
            freeScheduleItems.add(new FreeScheduleItem(scheduleRuleId, date, startOfItem, duration));
        }
        return freeScheduleItems;
    }