///<summary>Finds the שבת of the given פרשה.</summary>
///<param name="hebrewYear">The Hebrew year to look in.</param>
///<param name="parshaIndex">The index within the Parshiyos collection of the single פרשה to find.</param>
///<returns>The שבת of the פרשה.</returns>
public static HebrewDate Findפרשה(int hebrewYear, int parshaIndex)
{
if (parshaIndex < 0 || parshaIndex > Parshiyos.Count)
{
throw new ArgumentOutOfRangeException("parshaIndex");
}
if (parshaIndex > 52)
{
throw new ArgumentOutOfRangeException("parshaIndex", "Cannot search for double פרשה.");
}
var roshHashana = new HebrewDate(hebrewYear, HebrewMonth.תשרי, 1);
var array = parshaIndices[roshHashana];
var weekNumber = Array.IndexOf(array, parshaIndex);
//If this year doesn't have the פרשה separately, find the double פרשה.
//First, find the index in Parshiyos of the double פרשה's name.
//Then, locate that index in the year's array.
if (weekNumber == -1)
{
weekNumber = Array.IndexOf(array, Enumerable.Range(53, 7).First(i => Parshiyos[i].Contains(Parshiyos[parshaIndex])));
}
//TODO: Years without וילך
//Four year types don't have פרשת וילך. (See below)
//Right now, I return פרשת וילך of the previous (!) year
//(weekNumber becomes -1 because the double פרשה wasn't
//found, and, coincidentally, the last week of the previous
//year has וילך for all of these ParshaArrayKeys)
//Maybe I should throw, maybe I should return next year,
//maybe I should leave as is.
//These are the troublesome ParshaArrayKeys:
//True, חסר, Thursday
//False, כסדרן, Thursday
//False, חסר, Saturday
//False, מלא, Thursday
//Round ראש השנה to the next שבת before adding weeks.
return(roshHashana + (6 - (int)roshHashana.DayOfWeek + weekNumber * 7));
}
internal HebrewDayInfo(HebrewDate date)
{
Date = date;
}
///<summary>Creates a HebrewDateEventArgs from a Hebrew date.</summary>
public HebrewDateEventArgs(HebrewDate date)
{
Date = date;
}
} //Implicit cast
///<summary>Gets the last week day preceding a Hebrew date.</summary>
///<param name="date">The date.</param>
///<param name="dayOfWeek">The day of week to return.</param>
///<returns>The last dayOfWeek day preceding date, or date if it is on dayOfWeek.</returns>
public static HebrewDate Last(this HebrewDate date, DayOfWeek dayOfWeek)
{
return(date.EnglishDate.Last(dayOfWeek));
}
///<summary>Gets the first week day following a Hebrew date.</summary>
///<param name="date">The date.</param>
///<param name="dayOfWeek">The day of week to return.</param>
///<returns>The first dayOfWeek day following date, or date if it is on dayOfWeek.</returns>
public static HebrewDate Next(this HebrewDate date, DayOfWeek dayOfWeek)
{
return(date.EnglishDate.Next(dayOfWeek));
} //Implicit cast
public string this[HebrewDate roshHashana, int weekOfYear] {
get { return(this[roshHashana.IsLeapYear, roshHashana.YearType, roshHashana.DayOfWeek, weekOfYear]); }
}
public int[] this[HebrewDate roshHashana] {
get { return(this[roshHashana.IsLeapYear, roshHashana.YearType, roshHashana.DayOfWeek]); }
}
