/* kdate.js - Kaluach Javascript Hebrew date routines
 *   Version 0.03 (beta release)
 * Copyright (C) 5760 (2000 CE), by Abu Mami and Yisrael Hersch.
 *   All Rights Reserved.
 *   All copyright notices in this script must be left intact.
 * Based on the formula by Gauss
 * Terms of use:
 *   - Permission will be granted to use this script on personal
 *     web pages. All that's required is that you please ask.
 *     (Of course if you want to send a few dollars, that's OK too :-)
 *   - Use on commercial web sites requires a $50 payment.
 * website: http://www.kaluach.net
 * email: abu-mami@kaluach.net
 */


var now = new Date;
var tday = now.getDate();
var tweekday = now.getDay();
var tmonth = now.getMonth() + 1;
var tyear = now.getYear();
if(tyear < 1900)
	// if date from Netscape, then add 1900
	tyear += 1900;
var hebDate = civ2heb(tday, tmonth, tyear);
var hmS = hebDate.substring(hebDate.indexOf(' ')+1, hebDate.length);
var	hDay = eval(hebDate.substring(0, hebDate.indexOf(' ')));
var hMonth = eval(hmS.substring(0, hmS.indexOf(' ')));
var hYear = hmS.substring(hmS.indexOf(' ')+1, hmS.length);


function makeArray() {
	this[0] = makeArray.arguments.length;
	for (i = 0; i < makeArray.arguments.length; i = i + 1)
		this[i+1] = makeArray.arguments[i];
}



var civMonth = new makeArray(
	'January', 'February', 'March', 'April', 'May', 'June',
	'July', 'August', 'September', 'October', 'November', 'December');


	

function Gauss(year) {
	var a,b,c;
	var m;
	var	Mar;	// "day in March" on which Pesach falls (return value)

	a = Math.floor((12 * year + 17) % 19);
	b = Math.floor(year % 4);
	m = 32.044093161144 + 1.5542417966212 * a +  b / 4.0 - 0.0031777940220923 * year;
	if (m < 0)
		m -= 1;
	Mar = Math.floor(m);
	if (m < 0)
		m++;
	m -= Mar;

	c = Math.floor((Mar + 3 * year + 5 * b + 5) % 7);
	if(c == 0 && a > 11 && m >= 0.89772376543210 )
		Mar++;
	else if(c == 1 && a > 6 && m >= 0.63287037037037)
		Mar += 2;
	else if(c == 2 || c == 4 || c == 6)
		Mar++;

	Mar += Math.floor((year - 3760) / 100) - Math.floor((year - 3760) / 400) - 2;
	return Mar;
}

function leap(y) {
	return ((y % 400 == 0) || (y % 100 != 0 && y % 4 == 0));
}

function civMonthLength(month, year) {
	if(month == 2)
		return 28 + leap(year);
	else if(month == 4 || month == 6 || month == 9 || month == 11)
	   return 30;
	else
		return 31;
}

function civ2heb(day, month, year) {
	var d = day;
	var	m = month;
	var y = year;
	var hy;
	var pesach;
	var anchor;
	var adarType;

	m -= 2;
	if (m <= 0) { // Jan or Feb
		m += 12;
		y -= 1;
	}

	d += Math.floor(7 * m / 12 + 30 * (m - 1)); // day in March
	hy = y + 3760;	// get Hebrew year
	pesach = Gauss(hy);
	if (d <= pesach - 15) { // before 1 Nisan
		anchor = pesach;
		d += 365;
		if(leap(y))
			d++;
		y -= 1;
		hy -= 1;
		pesach = Gauss(hy);
	}
	else
		anchor = Gauss(hy + 1);

	d -= pesach - 15;
	anchor -= pesach - 12;
	y++;
	if(leap(y))
		anchor++;

	for(m = 0; m < 11; m++) {
		var days;
		if(m == 7 && anchor % 30 == 2)
			days = 30; // Cheshvan
		else if(m == 8 && anchor % 30 == 0)
			days = 29; // Kislev
		else
			days = 30 - m % 2;
		if(d <= days)
			break;
		d -= days;
	}

	adarType = 0;			// plain old Adar
	if (m == 11 && anchor >= 30) {
		if (d > 30) {
			adarType = 2;	// Adar 2
			d -= 30;
		}
		else
			adarType = 1;	// Adar 1
	}

	if(m >= 6)		// Tishrei or after?
		hy++;		// then bump up year

	if(m == 11)			// Adar?
		m += adarType;	// adjust for Adars

	return (d + ' ' + m + ' ' + hy);
}


function Easter(Y) {
	// based on the algorithm of Oudin
    var C = Math.floor(Y / 100);
    var N = Y - 19 * Math.floor(Y / 19);
    var K = Math.floor((C - 17) / 25);
    var I = C - Math.floor(C / 4) - Math.floor((C - K) / 3) + 19 * N + 15;
    I = I - 30*Math.floor((I / 30));
    I = I - Math.floor(I / 28) * (1 - Math.floor(I / 28) * Math.floor(29 / (I + 1)) * Math.floor((21 - N) / 11));
    var J = Y + Math.floor(Y / 4) + I + 2 - C + Math.floor(C / 4);
    J = J - 7 * Math.floor(J / 7);
    var L = I - J;
    var M = 3 + Math.floor((L + 40) / 44);
    var D = L + 28 - 31 * Math.floor(M / 4);

	var ret = new Object();
	ret[1] = M;
	ret[2] = D;
	return ret;
}

function DOW(day,month,year) {
	var a = Math.floor((14 - month)/12);
	var y = year - a;
	var m = month + 12*a - 2;
	var d = (day + y + Math.floor(y/4) - Math.floor(y/100) +
			Math.floor(y/400) + Math.floor((31*m)/12)) % 7;
	return d + 1;
}

function NthDOW(nth,weekday,month,year) {
	if (nth > 0)
		return (nth - 1) * 7 + 1 + (7 + weekday - DOW((nth - 1) * 7 + 1, month, year)) % 7;
	var days = civMonthLength(month, year);
	return days - (DOW(days, month, year) - weekday + 7) % 7;
}

//function holidays(cday, cmonth, cyear) {
//	// American civil holidays and some major religious holiday
//	if (cmonth == 1 && cday == 1)
//		return "New Year's Day";
//	else if (cmonth == 2 && cday == 12)
//		return "Lincoln's Birthday";
//	else if (cmonth == 2 && cday == 14)
//		return "Valentine's Day";
//	else if (cmonth == 2 && cday == NthDOW(3, 2, 2, cyear))
//		return "President's Day";
//	else if (cmonth == 3 && cday == 17)
//		return "St. Patrick's Day";
//	else if (cmonth == 3 || cmonth == 4) {
//		var e = Easter(cyear);
//	    if (cmonth == e[1] && cday == e[2])
//			return "Easter";
//	}
//	else if (cmonth == 5 && cday == NthDOW(2, 1, 5, cyear))
//		return "Mother's Day";
//	else if (cmonth == 5 && cday == NthDOW(3, 7, 5, cyear))
//		return "Armed Forces Day";
//	else if (cmonth == 5 && cday == NthDOW(0, 2, 5, cyear))
//		return "Memorial Day";
//	else if (cmonth == 6 && cday == 14)
//		return "Flag Day";
//	else if (cmonth == 6 && cday == NthDOW(3, 1, 6, cyear))
//		return "Father's Day";
//	else if (cmonth == 7 && cday == 4)
//		return "Independence Day";
//	else if (cmonth == 9 && cday == NthDOW(1, 2, 9, cyear))
//		return "Labor Day";
//	else if (cmonth == 10 && cday == NthDOW(2, 2, 10, cyear))
//		return "Columbus Day";
//	else if (cmonth == 10 && cday == 31)
//		return "Halloween";
//	else if (cmonth == 11 && cday == 11)
//		return "Veterans' Day";
//	else if (cmonth == 11 && cday == NthDOW(4, 5, 11, cyear))
//		return "Thanksgiving";
//	else if (cmonth == 12 && cday == 25)
//		return "Christmas";

//	return "";
//}

//function moadim(cday, cmonth, cyear, hday, hmonth, dow) {
//	if(hmonth == 6) {
//		if(hday == 1 || hday == 2)
//			return "Rosh Hashana"
//		else if(hday == 3 && dow != 7)
//			return "Fast of Gedalia";
//		else if(hday == 4 && dow == 1)
//			return "Fast of Gedalia";
//		else if(hday == 10)
//			return "Yom Kippur"
//		else if(hday >= 15 && hday <= 22)
//			return "Sukkot"
//		else if(hday == 23)
//			return "Sukkot (d)"
//	}
//	else if(hmonth == 8) {
//		if(hday >= 25)
//			return "Chanukkah"
//	}
//	else if(hmonth == 9) {
//		if(hday <= 2) {
//			return "Chanukkah"
//		}
//		else if(hday == 3) {
//			// Kislev can be malei or chaser
//			if(cday == 1) {
//				cday = 29;
//				cmonth = 11;
//			}
//			else if(cday == 2) {
//				cday = 30;
//				cmonth = 11;
//			}
//			else
//				cday -= 3;
//			var hdate = civ2heb(cday, cmonth, cyear);
//			hd = eval(hdate.substring(0, hdate.indexOf(' ')));
//			if(hd == 29)
//				return "Chanukkah"
//		}
//		else if(hday == 10)
//			return "Fast of Tevet"
//	}
//	else if(hmonth == 10) {
//		if(hday==15)
//			return "Tu b'Shvat"
//	}
//	else if(hmonth == 11 || hmonth == 13) {
//		if(hday == 11 && dow == 5)
//			return "Taanit Esther"
//		else if(hday == 13 && dow != 7)
//			return "Taanit Esther"
//		else if(hday == 14)
//			return "Purim"
//		else if(hday == 15)
//			return "Shushan Purim"
//	}
//	else if(hmonth == 0) {

//		if(hday == 12 && dow == 5)
//			return "Taanit Bechorot"
//		else if(hday == 14 && dow != 7)
//			return "Taanit Bechorot"
//		else if(hday >= 15 && hday <= 21)
//			return "Pesach"
//		else if(hday == 22)
//			return "Pesach (d)"
//	}
//	else if(hmonth == 1) {
//		if(hday == 3 && dow == 5)
//			return "Yom Ha'Atzmaut"
//		else if(hday == 4 && dow == 5)
//			return "Yom Ha'Atzmaut"
//		else if(hday == 5 && dow != 6 && dow != 7)
//			return "Yom Ha'Atzmaut"
//		if(hday == 14)
//			return "Pesah sheni"
//		else if(hday == 18)
//			return "Lag B'Omer"
//		if(hday == 28)
//			return "Yom Yerushalayim"
//	}
//	else if(hmonth == 2) {
//		if(hday == 6)
//			return "Shavuot"
//		else if(hday == 7)
//			return "Shavuot (d)"
//	}
//	else if(hmonth == 3) {
//		if(hday == 17 && dow != 7)
//			return "Fast of Tammuz"
//		if(hday == 18 && dow == 1)
//			return "Fast of Tammuz"
//	}
//	else if(hmonth == 4) {
//		if(hday == 9 && dow != 7)
//			return "Tisha B'Av"
//		if(hday == 10 && dow == 1)
//			return "Tisha B'Av"
//		if(hday == 15)
//			return "Tu B'Av"
//	}

//	return "";
//}