/* ksZman.js based on ksun.js & kzman.js of kaluach
 *
 * ksun.js - Kaluach suntimes Javascript routines
 *   Version 1.00 (initial release)
 *   Version 1.01 (fixed bug with time adjust - AM/PM and 24 hour clock)
 *   Version 1.02 (fixed bug with time adjust [again] - AM/PM and 24 hour clock)
 *   Version 2.00 (new suntimes routine, original routine was buggy)
 *   Version 2.01 (handle invalid sunrise/set, different knissat shabbat times)
 * Copyright (C) 5760-5763 (2000 - 2003 CE), by Abu Mami and Yisrael Hersch.
 *   All Rights Reserved.
 *   All copyright notices in this script must be left intact.
 * Based on:
 *   - PHP code that was translated by mattf@mail.com from the original perl
 *     module Astro-SunTime-0.01
 *	 - original version of ksun.js was based on the program SUN.C by Michael
 *     Schwartz, which was based on an algorithm contained in:
 *         Almanac for Computers, 1990
 *         published by Nautical Almanac Office
 *         United States Naval Observatory
 *         Washington, DC 20392
 * Permission will be granted to use this script on your web page
 *   if you wish. All that's required is that you please ask.
 *   (Of course if you want to send a few dollars, that's OK too :-)
 * website: http://www.kaluach.net
 * email: abumami@kaluach.org
 */

var monCount = new ksMakeArray(1, 32, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366);

var nsi, ewi;
var i;

var curDDay, curDMonth, curDYear;		// current or setted date
var curShDay, curShMonth, curShYear;		// current or setted date
var Ddst = 0;				// daylight saving time
var SHdst = 0;				// daylight saving time
var curGMT;				// the current time zone
var Dadj, SHadj;				// time zone + dst
var ampm = 0;				// am/pm or 24 hour display
var lat = 0, lng = 0;			// sun's location
var latd = -1, latm = 0;		// lat on earth
var lngd = -1, lngm = 0;		// long on earth
var ns, ew;				// hemisphere

var hanetz, shkia, shaa_zmanit, alot, misheyakir, tzeit;
var shema, tefillah, chatzot, minchag, minchak, plag;
var knissatShabbat, motzeiShabbat, rabenuTam;
var sunrise, sunset;

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

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

function doy(d, m, y) {
	return monCount[m] + d + (m > 2 && ksLeap(y));
}


function suntime(
	dy, mn, yr,
	sundeg, sunmin,
	londeg, lonmin, ew,
	latdeg, latmin, ns,
	timezone)
{
	var invalid = 0;	// start out as OK

	longitude = (londeg + lonmin/60.0) * ((ew == 0) ? -1 : 1);
	latitude  = (latdeg + latmin/60.0) * ((ns == 0) ? 1 : -1);

	var yday = doy(dy, mn, yr);

	var A = 1.5708; 
	var B = 3.14159; 
	var C = 4.71239; 
	var D = 6.28319;      
	var E = 0.0174533 * latitude; 
	var F = 0.0174533 * longitude; 
	var G = 0.261799 * timezone; 

	var R = Math.cos(0.01745 * (sundeg + sunmin/60.0));

	var J;

	// two times through the loop
	//    i=0 is for sunrise
	//    i=1 is for sunset
	for (i = 0; i < 2; i++) { 

		if(!i)
			J =  A;	// sunrise 
		else
			J = C;	// sunset

		var K = yday + ((J - F) / D); 
		var L = (K * .017202) - .0574039;              // Solar Mean Anomoly 
		var M = L + .0334405 * Math.sin(L);            // Solar True Longitude 
		M += 4.93289 + (3.49066E-04) * Math.sin(2 * L); 
		
		// Quadrant Determination 
		if (D == 0) {
			alert("Trying to normalize with zero offset...");
			exit;
		} 

		while(M < 0)
			M = (M + D);

		while(M >= D)
			M = (M - D);

		if ((M / A) - Math.floor(M / A) == 0)
			M += 4.84814E-06;

		var P = Math.sin(M) / Math.cos(M);                   // Solar Right Ascension 
		P = Math.atan2(.91746 * P, 1); 

		// Quadrant Adjustment 
		if (M > C)
			P += D;
		else {
			if (M > A)
				P += B;
		} 

		var Q = .39782 * Math.sin(M);      // Solar Declination 
		Q = Q / Math.sqrt(-Q * Q + 1);     // This is how the original author wrote it! 
		Q = Math.atan2(Q, 1); 

		var S = R - (Math.sin(Q) * Math.sin(E)); 
		S = S / (Math.cos(Q) * Math.cos(E)); 

		if(Math.abs(S) > 1)
			invalid = 1;	// uh oh! no sunrise/sunset

		S = S / Math.sqrt(-S * S + 1); 
		S = A - Math.atan2(S, 1); 

		if(!i)
			S = D - S;	// sunrise

		var T = S + P - 0.0172028 * K - 1.73364;  // Local apparent time 
		var U = T - F;                            // Universal timer 
		var V = U + G;                            // Wall clock time 
		
		// Quadrant Determination 
		if(D == 0) {
			alert("Trying to normalize with zero offset...");
			exit;
		} 
		
		while(V < 0)
			V = V + D;
		while(V >= D)
			V = V - D;
		V = V * 3.81972; 

		if(!i)
			sr = V;	// sunrise
		else
			ss = V;	// sunset
	} 

	var ret = new Object();
	ret[1] = invalid;
	ret[2] = sr;
	ret[3] = ss;
	return ret;
}


function timeadj(t, ampm) {
	var hour;
	var min;

	var time = t;

	var hour = Math.floor(time);
	var min  = Math.floor((time - hour) * 60.0 + 0.5);

	if(min >= 60) {
		hour += 1;
		min  -= 60;
	}

	if(hour < 0)
		hour += 24;

	if(ampm) {
		ampm_str = (hour > 11) ? ' PM' : ' AM';
		hour %= 12;
		hour = (hour < 1) ? 12 : hour;
	}
	else
		ampm_str = '';

	var str = hour + ':' + ((min < 10) ? '0' : '') + min + ampm_str;
//	var str = hour + ':' + min + ampm_str;
	return str;

}

function set_Ddst(){
	Ddst = dayDST.checked;
	Dadj = curGMT+ (Ddst*1);
	setDayTimes();
}

function set_Shdst(){
	SHdst = shbtDST.checked;
	SHadj = curGMT+ (SHdst*1);
	setShbtTimes();
}

function isValidDate(d, m, y){
	var isValidD = true;
	var curLen = civMonthLength(m, y);
	if(m < 1 || m > 12){
		isValidD = false;
	}
	else if(d < 1 || d > curLen){
		isValidD = false;
	}
	return (isValidD);	
}

function setDefDate(){
	var myDate;
	myDate = new Date();
	curDDay = myDate.getDate();
	curShDay = myDate.getDate();
	curDMonth = myDate.getMonth()+1;
	curShMonth = myDate.getMonth()+1;
	curDYear = myDate.getYear();
	if(curDYear < 1000) curDYear += 1900;
	curShYear = myDate.getYear();
	if(curShYear < 1000) curShYear += 1900;
}

function setDzCmbo(){
	document.getElementById("dDayT").selectedIndex = curDDay-1;
	document.getElementById("mDayT").selectedIndex = curDMonth-1;
	document.getElementById("yDayT").selectedIndex = curDYear-2004;
}

function setSHzCmbo(){
	document.getElementById("dShbtT").selectedIndex = curShDay-1;
	document.getElementById("mShbtT").selectedIndex = curShMonth-1;
	document.getElementById("yShbtT").selectedIndex = curShYear-2004;
}

function setDefPlace(){
	placename = "Jerusalem";
	ns = 'N';
	ew = 'E';
	latd = 31;
	latm = 24;
	lngd = 35;
	lngm = 00;
	curGMT = 2;
	Dadj = curGMT + Ddst;
	SHadj = curGMT + SHdst;
	nsi = (ns == 'N') ? 0 : 1;
	ewi = (ew == 'W') ? 0 : 1;
}

function setDdate(d, m, y){
	var myDate;
	if(isValidDate(d, m, y)){
		myDate = new Date(y, m-1, d, 12, 0, 0, 0);
	}
	else{
		myDate = new Date();
	}
	curDDay = myDate.getDate();
	curDMonth = myDate.getMonth()+1;
	curDYear = myDate.getYear();
	if(curDYear < 1000) curDYear += 1900;
}

function setShdate(d, m, y){
	var myDate;
	if(isValidDate(d, m, y)){
		myDate = new Date(y, m-1, d, 12, 0, 0, 0);
	}
	else{
		myDate = new Date();
	}
	curShDay = myDate.getDate();
	curShMonth = myDate.getMonth()+1;
	curShYear = myDate.getYear();
	if(curShYear < 1000) curShYear += 1900;
}

function set2place(pName, curNS, curEW, ltd, ltm, lgd, lgm, cGmt){
	placename = pName;
	ns = curNS;
	ew = curEW;
	latd = (ltd*1);
	latm = (ltm*1);
	lngd = (lgd*1);
	lngm = (lgm*1);
	curGMT = (cGmt*1);
	Dadj = curGMT+ (Ddst*1);
	SHadj = curGMT+ (SHdst*1);
	nsi = (ns == 'N') ? 0 : 1;
	ewi = (ew == 'W') ? 0 : 1;
}

function setDayTimes(){
	var d = curDDay;
	var m = curDMonth;
	var y = curDYear;
	var time;

	time = suntime(d, m, y, 90, 50, lngd, lngm, ewi, latd, latm, nsi, Dadj);
	if(time[1] == 0) {
		sunrise = time[2];
		sunset  = time[3];
		hanetz = timeadj(sunrise, ampm);
		shkia = timeadj(sunset, ampm);
		shaa_zmanit = (sunset - sunrise) / 12;
	}
	else {
		hanetz = "";
		shkia = "";
	}

	time = suntime(d, m, y, 106, 6, lngd, lngm, ewi, latd, latm, nsi, Dadj);
	if(time[1] == 0)
		alot = timeadj(time[2], ampm);
	else
		alot = "";
	//alert("alot: " + alot + ", Date: " + curDDay + "/" + curDMonth + "/" + curDYear)
	//alert(lngd + ", " + lngm + ", " + ewi + ", " + latd + ", " + latm + ", " + nsi + ", " + Dadj)
	time = suntime(d, m, y, 101, 0, lngd, lngm, ewi, latd, latm, nsi, Dadj);
	if(time[1] == 0)
		misheyakir = timeadj(time[2], ampm);
	else
		misheyakir = "";

	time = suntime(d, m, y, 96, 0, lngd, lngm, ewi, latd, latm, nsi, Dadj);
	if(time[1] == 0)
		tzeit = timeadj(time[3], ampm);
	else	
		tzeit = "";

	shema = timeadj(sunrise + shaa_zmanit * 3, ampm);
	tefillah = timeadj(sunrise + shaa_zmanit * 4, ampm);
	chatzot = timeadj(sunrise + shaa_zmanit * 6, ampm);
	minchag  = timeadj(sunrise + shaa_zmanit * 6.5, ampm);
	minchak = timeadj(sunrise + shaa_zmanit * 9.5, ampm);
	plag = timeadj(sunrise + shaa_zmanit * 10.75, ampm);
}

function setShbtTimes(){
	var d = curShDay;
	var m = curShMonth;
	var y = curShYear;
	var time;

	var yom = new Date (y, m-1, d);
	var len = civMonthLength(curShMonth, curShYear);
	while(yom.getDay() != 6){
		if(d == len) {
			if(curShMonth == 12){
				y++;
				m = 1;
			}
			else{
				m++;
			}
			d = 1;
		}
		else{
			d++;
		}
		yom = new Date (y, m-1, d);
	}
	// motzei shabbat (3 small stars)
	time = suntime(d, m, y, 98, 30, lngd, lngm, ewi, latd, latm, nsi, SHadj);
	if(time[1] == 0)
		motzeiShabbat = timeadj(time[3], ampm);
	else
		motzeiShabbat = "";
	var tmpTime, rabTam;
	tmpTime = suntime(d, m, y, 90, 50, lngd, lngm, ewi, latd, latm, nsi, SHadj);
	if(tmpTime[1] == 0) {
		rabTam  = tmpTime[3]+1.2;
		rabenuTam = timeadj(rabTam, ampm);
	}
	else{
		rabenuTam = "";
	}
	// knissat shabbat (sunset from day before)
	var day_before = new Date(yom.getTime() - 86400000);
	db = day_before.getDate();
	mb = day_before.getMonth() + 1;
	yb = day_before.getYear();
	if(yb < 1900)
		yb += 1900;
	time = suntime(db, mb, yb, 90, 50, lngd, lngm, ewi, latd, latm, nsi, SHadj);
	if(placename == "Jerusalem")
		knissatShabbat = timeadj(time[3] - 40.0/60.0, ampm);
	else if(placename == "Haifa")
		knissatShabbat = timeadj(time[3] - 30.0/60.0, ampm);
	else if(placename == "Beer Sheva")
		knissatShabbat = timeadj(time[3] - 30.0/60.0, ampm);
	else if(placename == "Karnei Shomron")
		knissatShabbat = timeadj(time[3] - 22.0/60.0, ampm);
	else if(placename == "Tel Aviv")
		knissatShabbat = timeadj(time[3] - 22.0/60.0, ampm);
	else
		knissatShabbat = timeadj(time[3] - 18.0/60.0, ampm);
}

function getHanetz(){
	return (hanetz);
}

function getShkia(){
	return (shkia);
}

function getAlot(){
	return (alot);
}

function getMisheyakir(){
	return (misheyakir);
}

function getTzeit(){
	return (tzeit);
}

function getShema(){
	return (shema);
}

function getTefillah(){
	return (tefillah);
}

function getChatzot(){
	return (chatzot);
}

function getMinchag(){
	return (minchag);
}

function getMinchak(){
	return (minchak);
}

function getPlag(){
	return (plag);
}

function getKnissatShabbat(){
	return (knissatShabbat);
}

function getMotzeiShabbat(){
	return (motzeiShabbat);
}

function getRabenuTam(){
	return (rabenuTam);
}

//Default - today
setDefDate();
//Default - place (Jerusalem)
setDefPlace();
//times for default
setDayTimes();
setShbtTimes();