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BangleApps/apps/hebrew_calendar/hebrewDate.js

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/*!
* This script was taked from this page http://www.shamash.org/help/javadate.shtml and ported to Node.js by Ionică Bizău in https://github.com/IonicaBizau/hebrew-date
*
* This script was adapted from C sources written by
* Scott E. Lee, which contain the following copyright notice:
*
* Copyright 1993-1995, Scott E. Lee, all rights reserved.
* Permission granted to use, copy, modify, distribute and sell so long as
* the above copyright and this permission statement are retained in all
* copies. THERE IS NO WARRANTY - USE AT YOUR OWN RISK.
*
* Bill Hastings
* RBI Software Systems
* bhastings@rbi.com
*/
var _typeof = typeof Symbol === "function" && typeof Symbol.iterator === "symbol" ? function (obj) { return typeof obj; } : function (obj) { return obj && typeof Symbol === "function" && obj.constructor === Symbol && obj !== Symbol.prototype ? "symbol" : typeof obj; };
var GREG_SDN_OFFSET = 32045, DAYS_PER_5_MONTHS = 153, DAYS_PER_4_YEARS = 1461, DAYS_PER_400_YEARS = 146097;
var HALAKIM_PER_HOUR = 1080, HALAKIM_PER_DAY = 25920, HALAKIM_PER_LUNAR_CYCLE = 29 * HALAKIM_PER_DAY + 13753, HALAKIM_PER_METONIC_CYCLE = HALAKIM_PER_LUNAR_CYCLE * (12 * 19 + 7);
var HEB_SDN_OFFSET = 347997, NEW_MOON_OF_CREATION = 31524, NOON = 18 * HALAKIM_PER_HOUR, AM3_11_20 = 9 * HALAKIM_PER_HOUR + 204, AM9_32_43 = 15 * HALAKIM_PER_HOUR + 589;
var SUN = 0, MON = 1, TUES = 2, WED = 3, THUR = 4, FRI = 5, SAT = 6;
function weekdayarr(d0, d1, d2, d3, d4, d5, d6) {
this[0] = d0;
this[1] = d1;
this[2] = d2;
this[3] = d3;
this[4] = d4;
this[5] = d5;
this[6] = d6;
}
function gregmontharr(m0, m1, m2, m3, m4, m5, m6, m7, m8, m9, m10, m11) {
this[0] = m0;
this[1] = m1;
this[2] = m2;
this[3] = m3;
this[4] = m4;
this[5] = m5;
this[6] = m6;
this[7] = m7;
this[8] = m8;
this[9] = m9;
this[10] = m10;
this[11] = m11;
}
function hebrewmontharr(m0, m1, m2, m3, m4, m5, m6, m7, m8, m9, m10, m11, m12, m13) {
this[0] = m0;
this[1] = m1;
this[2] = m2;
this[3] = m3;
this[4] = m4;
this[5] = m5;
this[6] = m6;
this[7] = m7;
this[8] = m8;
this[9] = m9;
this[10] = m10;
this[11] = m11;
this[12] = m12;
this[13] = m13;
}
function monthsperyeararr(m0, m1, m2, m3, m4, m5, m6, m7, m8, m9, m10, m11, m12, m13, m14, m15, m16, m17, m18) {
this[0] = m0;
this[1] = m1;
this[2] = m2;
this[3] = m3;
this[4] = m4;
this[5] = m5;
this[6] = m6;
this[7] = m7;
this[8] = m8;
this[9] = m9;
this[10] = m10;
this[11] = m11;
this[12] = m12;
this[13] = m13;
this[14] = m14;
this[15] = m15;
this[16] = m16;
this[17] = m17;
this[18] = m18;
}
var gWeekday = new weekdayarr("Sun", "Mon", "Tues", "Wednes", "Thurs", "Fri", "Satur"), gMonth = new gregmontharr("January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December"), hMonth = new hebrewmontharr("Tishri", "Heshvan", "Kislev", "Tevet", "Shevat", "AdarI", "AdarII", "Nisan", "Iyyar", "Sivan", "Tammuz", "Av", "Elul"), mpy = new monthsperyeararr(12, 12, 13, 12, 12, 13, 12, 13, 12, 12, 13, 12, 12, 13, 12, 12, 13, 12, 13);
/**
* hebrewDate
* Convert the Gregorian dates into Hebrew calendar dates.
*
* @name hebrewDate
* @function
* @param {Date|Number} inputDate The date object (representing the Gregorian date) or the year.
* @return {Object} An object containing:
*
* - `year`: The Hebrew year.
* - `month`: The Hebrew month.
* - `month_name`: The Hebrew month name.
* - `date`: The Hebrew date.
*/
function hebrewDate(inputDateOrYear) {
var inputMonth, inputDate;
var hebrewMonth = 0, hebrewDate = 0, hebrewYear = 0, metonicCycle = 0, metonicYear = 0, moladDay = 0, moladHalakim = 0;
function GregorianToSdn(inputYear, inputMonth, inputDay) {
var year = 0, month = 0, sdn = void 0;
// Make year a positive number
if (inputYear < 0) {
year = inputYear + 4801;
}
else {
year = inputYear + 4800;
}
// Adjust the start of the year
if (inputMonth > 2) {
month = inputMonth - 3;
}
else {
month = inputMonth + 9;
year--;
}
sdn = Math.floor(Math.floor(year / 100) * DAYS_PER_400_YEARS / 4);
sdn += Math.floor(year % 100 * DAYS_PER_4_YEARS / 4);
sdn += Math.floor((month * DAYS_PER_5_MONTHS + 2) / 5);
sdn += inputDay - GREG_SDN_OFFSET;
return sdn;
}
function SdnToHebrew(sdn) {
var tishri1 = 0, tishri1After = 0, yearLength = 0, inputDay = sdn - HEB_SDN_OFFSET;
FindTishriMolad(inputDay);
tishri1 = Tishri1(metonicYear, moladDay, moladHalakim);
if (inputDay >= tishri1) {
// It found Tishri 1 at the start of the year.
hebrewYear = metonicCycle * 19 + metonicYear + 1;
if (inputDay < tishri1 + 59) {
if (inputDay < tishri1 + 30) {
hebrewMonth = 1;
hebrewDate = inputDay - tishri1 + 1;
}
else {
hebrewMonth = 2;
hebrewDate = inputDay - tishri1 - 29;
}
return;
}
// We need the length of the year to figure this out,so find Tishri 1 of the next year.
moladHalakim += HALAKIM_PER_LUNAR_CYCLE * mpy[metonicYear];
moladDay += Math.floor(moladHalakim / HALAKIM_PER_DAY);
moladHalakim = moladHalakim % HALAKIM_PER_DAY;
tishri1After = Tishri1((metonicYear + 1) % 19, moladDay, moladHalakim);
}
else {
// It found Tishri 1 at the end of the year.
hebrewYear = metonicCycle * 19 + metonicYear;
if (inputDay >= tishri1 - 177) {
// It is one of the last 6 months of the year.
if (inputDay > tishri1 - 30) {
hebrewMonth = 13;
hebrewDate = inputDay - tishri1 + 30;
}
else if (inputDay > tishri1 - 60) {
hebrewMonth = 12;
hebrewDate = inputDay - tishri1 + 60;
}
else if (inputDay > tishri1 - 89) {
hebrewMonth = 11;
hebrewDate = inputDay - tishri1 + 89;
}
else if (inputDay > tishri1 - 119) {
hebrewMonth = 10;
hebrewDate = inputDay - tishri1 + 119;
}
else if (inputDay > tishri1 - 148) {
hebrewMonth = 9;
hebrewDate = inputDay - tishri1 + 148;
}
else {
hebrewMonth = 8;
hebrewDate = inputDay - tishri1 + 178;
}
return;
}
else {
if (mpy[(hebrewYear - 1) % 19] == 13) {
hebrewMonth = 7;
hebrewDate = inputDay - tishri1 + 207;
if (hebrewDate > 0)
return;
hebrewMonth--;
hebrewDate += 30;
if (hebrewDate > 0)
return;
hebrewMonth--;
hebrewDate += 30;
}
else {
hebrewMonth = 6;
hebrewDate = inputDay - tishri1 + 207;
if (hebrewDate > 0)
return;
hebrewMonth--;
hebrewDate += 30;
}
if (hebrewDate > 0)
return;
hebrewMonth--;
hebrewDate += 29;
if (hebrewDate > 0)
return;
// We need the length of the year to figure this out,so find Tishri 1 of this year.
tishri1After = tishri1;
FindTishriMolad(moladDay - 365);
tishri1 = Tishri1(metonicYear, moladDay, moladHalakim);
}
}
yearLength = tishri1After - tishri1;
moladDay = inputDay - tishri1 - 29;
if (yearLength == 355 || yearLength == 385) {
// Heshvan has 30 days
if (moladDay <= 30) {
hebrewMonth = 2;
hebrewDate = moladDay;
return;
}
moladDay -= 30;
}
else {
// Heshvan has 29 days
if (moladDay <= 29) {
hebrewMonth = 2;
hebrewDate = moladDay;
return;
}
moladDay -= 29;
}
// It has to be Kislev.
hebrewMonth = 3;
hebrewDate = moladDay;
}
function FindTishriMolad(inputDay) {
// Estimate the metonic cycle number. Note that this may be an under
// estimate because there are 6939.6896 days in a metonic cycle not
// 6940,but it will never be an over estimate. The loop below will
// correct for any error in this estimate.
metonicCycle = Math.floor((inputDay + 310) / 6940);
// Calculate the time of the starting molad for this metonic cycle.
MoladOfMetonicCycle();
// If the above was an under estimate,increment the cycle number until
// the correct one is found. For modern dates this loop is about 98.6%
// likely to not execute,even once,because the above estimate is
// really quite close.
while (moladDay < inputDay - 6940 + 310) {
metonicCycle++;
moladHalakim += HALAKIM_PER_METONIC_CYCLE;
moladDay += Math.floor(moladHalakim / HALAKIM_PER_DAY);
moladHalakim = moladHalakim % HALAKIM_PER_DAY;
}
// Find the molad of Tishri closest to this date.
for (metonicYear = 0; metonicYear < 18; metonicYear++) {
if (moladDay > inputDay - 74)
break;
moladHalakim += HALAKIM_PER_LUNAR_CYCLE * mpy[metonicYear];
moladDay += Math.floor(moladHalakim / HALAKIM_PER_DAY);
moladHalakim = moladHalakim % HALAKIM_PER_DAY;
}
}
function MoladOfMetonicCycle() {
var r1 = void 0, r2 = void 0, d1 = void 0, d2 = void 0;
// Start with the time of the first molad after creation.
r1 = NEW_MOON_OF_CREATION;
// Calculate gMetonicCycle * HALAKIM_PER_METONIC_CYCLE. The upper 32
// bits of the result will be in r2 and the lower 16 bits will be in r1.
r1 += metonicCycle * (HALAKIM_PER_METONIC_CYCLE & 0xFFFF);
r2 = r1 >> 16;
r2 += metonicCycle * (HALAKIM_PER_METONIC_CYCLE >> 16 & 0xFFFF);
// Calculate r2r1 / HALAKIM_PER_DAY. The remainder will be in r1,the
// upper 16 bits of the quotient will be in d2 and the lower 16 bits
// will be in d1.
d2 = Math.floor(r2 / HALAKIM_PER_DAY);
r2 -= d2 * HALAKIM_PER_DAY;
r1 = r2 << 16 | r1 & 0xFFFF;
d1 = Math.floor(r1 / HALAKIM_PER_DAY);
r1 -= d1 * HALAKIM_PER_DAY;
moladDay = d2 << 16 | d1;
moladHalakim = r1;
}
function Tishri1(metonicYear, moladDay, moladHalakim) {
var tishri1 = moladDay, dow = tishri1 % 7, leapYear = metonicYear == 2 || metonicYear == 5 || metonicYear == 7 || metonicYear == 10 || metonicYear == 13 || metonicYear == 16 || metonicYear == 18, lastWasLeapYear = metonicYear == 3 || metonicYear == 6 || metonicYear == 8 || metonicYear == 11 || metonicYear == 14 || metonicYear == 17 || metonicYear == 0;
// Apply rules 2,3 and 4
if (moladHalakim >= NOON || !leapYear && dow == TUES && moladHalakim >= AM3_11_20 || lastWasLeapYear && dow == MON && moladHalakim >= AM9_32_43) {
tishri1++;
dow++;
if (dow == 7)
dow = 0;
}
// Apply rule 1 after the others because it can cause an additional delay of one day.
if (dow == WED || dow == FRI || dow == SUN) {
tishri1++;
}
return tishri1;
}
var inputYear = inputDateOrYear;
if ((typeof inputYear === "undefined" ? "undefined" : _typeof(inputYear)) === "object") {
inputMonth = inputDateOrYear.getMonth() + 1;
inputDate = inputDateOrYear.getDate();
inputYear = inputDateOrYear.getFullYear();
}
SdnToHebrew(GregorianToSdn(inputYear, inputMonth, inputDate));
return {
year: hebrewYear,
month: hebrewMonth,
date: hebrewDate,
month_name: hMonth[hebrewMonth - 1]
};
}
exports.hebrewDate = hebrewDate;
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