/// <summary>
/// Gets a string summary of this rule.
/// </summary>
/// <returns></returns>
public override string GetSummary()
{
if (FrequencyType == MonthlyFrequencyType.DayOfTheMonth)
{
//Occurs every {0} month(s) on day {1}
return(string.Format("Occurs every {0} month(s) on day {1} of the month", RepeatInterval, DayOfTheMonth));
}
else
{
return(string.Format("Occurs every {0} {1} of every {2} month(s)", CalculatedDayType.ToString().ToLower(), CalculcatedDayOption.ToString(), RepeatInterval));
}
}
/// <summary>
/// Calculates specific date rules for the given month.
/// </summary>
/// <param name="dt">The month and year to use.</param>
/// <param name="dayOption">The option we are calculating.</param>
/// <param name="instance">The instance of the option being calculated.</param>
/// <returns>The date of the instance of this option.</returns>
public static DateTime FindInstanceOfDay(this DateTime dt, CalculcatedDayOption dayOption, CalculatedDayType instance)
{
//The instance number corresponds to
int instanceNumber = (int)instance;
DateTime searchDay = new DateTime(dt.Year, dt.Month, 1);
int daysInMonth = DateTime.DaysInMonth(dt.Year, dt.Month);
if (dayOption == CalculcatedDayOption.Monday || dayOption == CalculcatedDayOption.Tuesday ||
dayOption == CalculcatedDayOption.Wednesday || dayOption == CalculcatedDayOption.Thursday ||
dayOption == CalculcatedDayOption.Friday || dayOption == CalculcatedDayOption.Saturday ||
dayOption == CalculcatedDayOption.Sunday)
{
//Converting to DayOfWeek used by DateTime.
DayOfWeek dayOfWeek = DayOfWeek.Monday;
switch (dayOption)
{
case CalculcatedDayOption.Monday:
dayOfWeek = DayOfWeek.Monday;
break;
case CalculcatedDayOption.Tuesday:
dayOfWeek = DayOfWeek.Tuesday;
break;
case CalculcatedDayOption.Wednesday:
dayOfWeek = DayOfWeek.Wednesday;
break;
case CalculcatedDayOption.Thursday:
dayOfWeek = DayOfWeek.Thursday;
break;
case CalculcatedDayOption.Friday:
dayOfWeek = DayOfWeek.Friday;
break;
case CalculcatedDayOption.Saturday:
dayOfWeek = DayOfWeek.Saturday;
break;
case CalculcatedDayOption.Sunday:
dayOfWeek = DayOfWeek.Monday;
break;
}
for (int i = 1; i <= 7; i++)
{
if (searchDay.DayOfWeek == dayOfWeek)
{
//Found the first instance.
//If there are not at least 28 days after the first instance
//then max instance is 4 otherwise it is 5.
if (instanceNumber >= 5)
{
int instanceDay = searchDay.Day;
if (daysInMonth - instanceDay < 28)
{
instanceNumber = 4;
}
else
{
instanceNumber = 5;
}
}
return(searchDay.AddDays(7 * (instanceNumber - 1)));
}
//Move to the next day.
searchDay = searchDay.AddDays(1);
}
}
else if (dayOption == CalculcatedDayOption.Day)
{
if (instanceNumber < 5)
{
return(searchDay.AddDays(instanceNumber - 1));
}
else
{
//last day of the month
return(searchDay.AddMonths(1).AddDays(-1));
}
}
else if (dayOption == CalculcatedDayOption.Weekday)
{
if (instanceNumber < 5)
{
int instanceCount = 0;
for (int i = 1; i <= daysInMonth; i++)
{
//Counting each instance of a weekday.
if (searchDay.DayOfWeek == DayOfWeek.Monday || searchDay.DayOfWeek == DayOfWeek.Tuesday ||
searchDay.DayOfWeek == DayOfWeek.Wednesday || searchDay.DayOfWeek == DayOfWeek.Thursday ||
searchDay.DayOfWeek == DayOfWeek.Friday)
{
instanceCount++;
}
if (instanceCount == instanceNumber)
{
//we found the nth instance of this weekend day.
return(searchDay);
}
searchDay = searchDay.AddDays(1);
}
}
else
{
//last weekend day of the month
DateTime lastInstance = new DateTime();
for (int i = 1; i <= daysInMonth; i++)
{
//Counting each instance of a weekeday.
if (searchDay.DayOfWeek == DayOfWeek.Monday || searchDay.DayOfWeek == DayOfWeek.Tuesday ||
searchDay.DayOfWeek == DayOfWeek.Wednesday || searchDay.DayOfWeek == DayOfWeek.Thursday ||
searchDay.DayOfWeek == DayOfWeek.Friday)
{
lastInstance = searchDay;
}
searchDay = searchDay.AddDays(1);
}
return(lastInstance);
}
}
else if (dayOption == CalculcatedDayOption.WeekendDay)
{
if (instanceNumber < 5)
{
int instanceCount = 0;
for (int i = 1; i < daysInMonth; i++)
{
//Counting each instance of saturday or sunday.
if (searchDay.DayOfWeek == DayOfWeek.Saturday || searchDay.DayOfWeek == DayOfWeek.Sunday)
{
instanceCount++;
}
if (instanceCount == instanceNumber)
{
//we found the nth instance of this weekend day.
return(searchDay);
}
searchDay = searchDay.AddDays(1);
}
}
else
{
//last weekend day of the month
DateTime lastInstance = new DateTime();
for (int i = 1; i < daysInMonth; i++)
{
//Counting each instance of saturday or sunday.
if (searchDay.DayOfWeek == DayOfWeek.Saturday || searchDay.DayOfWeek == DayOfWeek.Sunday)
{
lastInstance = searchDay;
}
searchDay = searchDay.AddDays(1);
}
return(lastInstance);
}
}
return(new DateTime());
}
