public DateTime GetNextOccurrence(DateTime baseTime)
{
var nextScheduleTime = new ScheduleTime(baseTime.AddSeconds(1));
return GetNextOccurrence(nextScheduleTime);
}
private void WrapToNextMinute(ScheduleTime next)
{
next.Minute++;
next.Second = SecondField.GetFirst().Value;
}
private void WrapToNextYear(ScheduleTime next)
{
next.Year++;
next.Month = MonthField.GetFirst().Value;
next.Day = DayOfMonthField.GetFirst().Value;
next.Hour = HourField.GetFirst().Value;
next.Minute = MinuteField.GetFirst().Value;
}
private void WrapToNextDay(ScheduleTime next)
{
next.Day++;
next.Hour = HourField.GetFirst().Value;
next.Minute = MinuteField.GetFirst().Value;
}
private void WrapToNextHour(ScheduleTime next)
{
next.Hour++;
next.Minute = MinuteField.GetFirst().Value;
}
private void CalculateNextScheduledMinute(ScheduleTime next)
{
CronValue scheduledMinute = MinuteField.GetNext(next.Minute);
if (scheduledMinute == CronValue.Wrapped)
{
WrapToNextHour(next);
}
else if (scheduledMinute.Value > next.Minute)
{
SetStartOfMinute(next, scheduledMinute);
}
else
{
next.Minute = scheduledMinute.Value;
}
}
private DateTime TryCorrectScheduleForDaysInMonth(ScheduleTime nextScheduleTime)
{
try
{
return CorrectScheduleForDaysInMonth(nextScheduleTime);
}
catch (ArgumentOutOfRangeException ex)
{
throw new CronException(ErrorMessages.NoScheduleFound, ex);
}
}
private void SetStartOfHour(ScheduleTime next, CronValue scheduledHour)
{
next.Hour = scheduledHour.Value;
next.Minute = MinuteField.GetFirst().Value;
}
private void SetStartOfMinute(ScheduleTime next, CronValue scheduledMinute)
{
next.Minute = scheduledMinute.Value;
next.Second = SecondField.GetFirst().Value;
}
private DateTime GetNextOccurrence(ScheduleTime nextScheduleTime)
{
CalculateNextScheduledSecond(nextScheduleTime);
CalculateNextScheduledMinute(nextScheduleTime);
CalculateNextScheduledHour(nextScheduleTime);
CalculateNextScheduledDay(nextScheduleTime);
CalculateNextScheduledMonth(nextScheduleTime);
var nextTime = TryCorrectScheduleForDaysInMonth(nextScheduleTime);
return CorrectScheduleForDayOfWeek(nextTime);
}
private void SetStartOfDay(ScheduleTime next, CronValue scheduledDay)
{
next.Day = scheduledDay.Value;
next.Hour = HourField.GetFirst().Value;
next.Minute = MinuteField.GetFirst().Value;
}
private DateTime CorrectScheduleForDaysInMonth(ScheduleTime nextScheduleTime)
{
for (int i = 0; i <= MaxDayInMonthFixAttempts; i++)
{
if (MonthContainsDate(nextScheduleTime))
{
return nextScheduleTime.ToDateTime();
}
WrapToNextMonth(nextScheduleTime);
CalculateNextScheduledMonth(nextScheduleTime);
}
throw new CronException(ErrorMessages.NoScheduleFound);
}
private void CalculateNextScheduledSecond(ScheduleTime next)
{
CronValue scheduledSecond = SecondField.GetNext(next.Second);
if (scheduledSecond == CronValue.Wrapped)
{
WrapToNextMinute(next);
}
else
{
next.Second = scheduledSecond.Value;
}
}
private void CalculateNextScheduledMonth(ScheduleTime next)
{
CronValue scheduledMonth = MonthField.GetNext(next.Month);
if (scheduledMonth == CronValue.Wrapped)
{
WrapToNextYear(next);
}
else if (scheduledMonth.Value > next.Month)
{
SetStartOfMonth(next, scheduledMonth);
}
else
{
next.Month = scheduledMonth.Value;
}
}
private static bool MonthContainsDate(ScheduleTime nextScheduleTime)
{
return nextScheduleTime.Day <= Calendar.GetDaysInMonth(nextScheduleTime.Year, nextScheduleTime.Month);
}
private void SetStartOfMonth(ScheduleTime next, CronValue scheduledMonth)
{
next.Month = scheduledMonth.Value;
next.Day = DayOfMonthField.GetFirst().Value;
next.Hour = HourField.GetFirst().Value;
next.Minute = MinuteField.GetFirst().Value;
}
private void CalculateNextScheduledDay(ScheduleTime next)
{
CronValue scheduledDay = DayOfMonthField.GetNext(next.Day);
if (scheduledDay == CronValue.Wrapped)
{
WrapToNextMonth(next);
}
else if (scheduledDay.Value > next.Day)
{
SetStartOfDay(next, scheduledDay);
}
else
{
next.Day = scheduledDay.Value;
}
}
private void CalculateNextScheduledHour(ScheduleTime next)
{
CronValue scheduledHour = HourField.GetNext(next.Hour);
if (scheduledHour == CronValue.Wrapped)
{
WrapToNextDay(next);
}
else if (scheduledHour.Value > next.Hour)
{
SetStartOfHour(next, scheduledHour);
}
else
{
next.Hour = scheduledHour.Value;
}
}