/// <summary>
/// Constructs an <b>Interval</b> from the provided multiplier and time
/// unit.
/// </summary>
/// <param name="multiplier">The time period multiplier.</param>
/// <param name="period">The time period unit.</param>
public Interval(int multiplier, Period period)
{
this.multiplier = multiplier;
this.period = period;
}
/// <summary>
/// Determines if an <b>Interval</b> will divide the time period delimited
/// by two dates exactly.
/// </summary>
/// <param name="first">The first date.</param>
/// <param name="last">The last date.</param>
/// <returns><b>true</b> if the <b>Interval</b> exactly divides the two
/// dates an integer number of times.</returns>
public bool DividesDates(Date first, Date last)
{
int multiplier = this.multiplier;
Period period = this.period;
if (period == Period.TERM)
return (multiplier == 1);
if (period == Period.WEEK) {
period = Period.DAY;
multiplier *= 7;
}
if (period == Period.YEAR) {
if (first.Month != last.Month) return (false);
if (first.DayOfMonth != last.DayOfMonth) return (false);
return (((last.Year - first.Year) % multiplier) == 0);
}
if (period == Period.MONTH) {
if (first.DayOfMonth != last.DayOfMonth) return (false);
return ((((last.Year - first.Year) * 12 + last.Month - first.Month) % multiplier) == 0);
}
return (((last.GetHashCode () - first.GetHashCode ()) % multiplier) == 0);
}
