<?php
## this file name is 'class.lunar.php'
##
## lunar object -- get moon position or sun <-> moon, constellation, eclipses
##
## [author]
##  - Chilbong Kim, <san2(at)linuxchannel.net>
##  - http://linuxchannel.net/
##
## [changes]
##  - 2011.04.24 : add easter()
##  - 2011.04.08 : bug fixed of _newmoon(): $ffx[20170226] was unsed
##  - 2010.10.15 : bug fixed of _constellation()
##  - 2010.05.17 : critical bug fixed, _newmooninfo()
##  - 2009.06.08 : extended, date() to calendar::_date(), mktime() to calendar::_mktime() of class.calendar.php
##  - 2007.09.27 : bug fixed, tolunar(): current-fullmoon argument(1296000->1382400)
##  - 2005.02.25 : patch _gettm()
##  - 2005.02.16 : _getutimestr() rename to _newmooninfo()
##  - 2005.02.15 : _conjunction() rename to _newmoon()
##  - 2005.02.03 : bug fixed, moon()
##  - 2005.02.02 : bug fixed, tosolar()
##  - 2005.01.24 : new build
##
## [conjunction error by approximative method]
##  - avg: -6538 seconds(+598 seconds, -11787 seconds)
##
## [conjunction error by approximative method day patch]
##  - avg: -368 seconds(+592 seconds, -1081 seconds)
##  - but, wrong day not exists :)
##
## [valid date]
##  - solar : 1902-01-10 - 2038-01-18
##  - lunar : 1901-12-01 - 2037-12-14
##
## [support date]
##  - unix timestamp base: 1902-01-01 00:00:00 <= date <= 2037-12-31 23:59:59 (guess)
##  - JD(Julian Day) base: BC 4713-01-01 12:00 GMT <= Gregorian date <= AD 9999 (guess)
##
## [support date table - further]
##  ----------------------------------------------------------------------
##  -4712  -1999  1391  1902  2037  2050  4000  9999
##  ----------------------------------------------------------------------
##                        A     A                      current
##                  A     A     A     A                base on KASI.RE.KR
##            B     A     A     A     A     B          base on NASA
##    C       B     A     A     A     A     B     C    only cacurating
##  ----------------------------------------------------------------------
##  - A: support lunar date and leap, both exactly              
##  - B: support lunar date and leap, but leap not exactly              
##  - C: only computing, both not exactly
##
## [download & online source view]
##  - http://ftp.linuxchannel.net/devel/php_lunar/
##  - http://ftp.linuxchannel.net/devel/php_calendar/
##
## [demo]
##  - http://linuxchannel.net/gaggle/lunar.php
##
## [docs]
##  - http://linuxchannel.net/docs/lunar.txt
##
## [study]
##  - http://www.kao.re.kr/html/study/qna/index.html
##  - http://sunearth.gsfc.nasa.gov/eclipse/SEsaros/SEsaros.html
##  - Synodic Month (new moon to new moon)     29.53059 days  = 29d 12h 44m (A)
##  - Draconic Month (node to node)            27.21222 days  = 27d 05h 06m (B)
##  - Anomalistic Month (perigee to perigee)   27.55455 days  = 27d 13h 19m
##  - (223 * A) = 6585.36 days, (242 * B) = 6585.32 days 
##  - 1 Saros = 6585.32 days = 18 years 11 days 8 hours
## 
## [eclipses]
##  - Solar Eclipses: T(Total), A(Annular), H(Hybrid(Annular/Total)), P(Partial)
##  - Lunar Eclipses: t(Total), p(Umbral(Partial)), n(Penumbral)
##
## [eclipses(e) by this program]
##  - S A 104 0.010582273616323 1.06751983653440(1.067743)
##  - S T  91 0.014674627401046 1.04166992331860
##  - S H   6 0.210833791736160 0.96121766199154(0.964180)
##  - S P 106 0.829402137331320 1.59530999819400
##  - L t 114 0.010630181434784 0.52538271749109(0.527908)
##  - L p  85 0.294681791935650 1.14183526374750
##  - L n 111 0.832900661071600 1.57436507046800(1.578244)
##
## [reference]
##  - http://user.chollian.net/~kimdbin/re/moonpos.html
##  - http://zimmer.csufresno.edu/~fringwal/skycalc.c
##  - http://williams.best.vwh.net/sunrise_sunset_example.htm
##  - http://aa.usno.navy.mil/faq/docs/SunApprox.html
##  - ftp://ssd.jpl.nasa.gov/pub/eph/export/C-versions/hoffman/
##  - http://www.linuxchannel.net/docs/solar-24terms.txt
##  - http://home.tiscali.se/pausch/ // good, same as below
##  - http://www.stjarnhimlen.se/english.html  // good, planetary positions, rise/set time etc
##  - http://www.stargazing.net/kepler/ // good, approximate astronomical postions
##  - http://sunearth.gsfc.nasa.gov/eclipse/eclipse.html // good
##  - http://sunearth.gsfc.nasa.gov/eclipse/phase/phasecat.html
##  - http://sunearth.gsfc.nasa.gov/eclipse/phase/phase2001gmt.html
##  - http://sunearth.gsfc.nasa.gov/eclipse/LEvis/LEaltitude.html
##  - http://sunearth.gsfc.nasa.gov/eclipse/resource.html
##  - http://www.mreclipse.com/Special/SEprimer.html // Solar Eclipses for Beginners
##  - http://www.mreclipse.com/Special/LEprimer.html // Lunar Eclipses for Beginners
##  - http://www.mreclipse.com/MrEclipse.html // for Beginners
##  - http://astronote.org/
##  - http://myhome.naver.com/dudwn1109/appearance/solor_eclipse.htm
##  - http://www.kao.re.kr/html/study/
##

## private _solar
##
class _solar
{
  ## private, get JD(julian day)
  ##
  ## D -- get the number of days from base JD
  ## D = JD(Julian Day) - 2451545.0, base JD(J2000.0)
  ##
  ## base position (J2000.0), 2000-01-01 12:00:00, UT
  ## as   mktime(12,0,0-64,1,1,2000) == 946695536 unix timestamp at KST
  ## as gmmktime(12,0,0-64,1,1,2000) == 946727936 unix timestamp at GMT
  ##
  function &_getjd($utime)
  {
	$D = $utime - 946727936; // number of time
	$D = sprintf('%.13f',$D/86400); // float, number of days
	$JD= sprintf('%.13f',$D+2451545.0); // float, Julian Day
	$J = sprintf('%.4f',2000.0+($D/365.25)); // Jxxxx.xxxx format
	$T = sprintf('%.13f',$D/36525.0); // Julian century

	return array($JD,$J,$D,$T);
  }

  /***
  ## ftp://ssd.jpl.nasa.gov/pub/eph/export/C-versions/hoffman/
  ##
  function &__getjd($Y, $M=0, $D=0, $H=0, $I=0, $S=0)
  {
	$H -= 9; // KST to UT
	if(func_num_args() < 6)
	{ list($Y,$M,$D,$H,$I,$S) = explode(' ',gmdate('Y n j G i s',$Y)); }

	if($M < 3) { $M += 12; $Y--; }

	$D += ($H/24.0) + ($I/1440.0) + ($S/86400.0);
	$A = floor($Y/100.0);
	$B = 2.0 - $A + floor($A/4.0);

	$JD= sprintf('%.13f',floor(365.25*($Y+4716.0))+floor(30.6001*($M+1.0))+$D+$B-1524.5);
	$D = sprintf('%.13f',$JD-2451545.0); // float, number of days
	$J = sprintf('%.4f',2000.0+($D/365.25)); // // Jxxxx.xxxx format
	$T = sprintf('%.13f',$D/36525.0); // // Julian century

	return array($JD,$J,$D,$T);
  }

  ## priate, get D
  ## base 2000-01-00.00 TDT == 1999-12-31 TDT == J2000.0 + 1.5
  ## http://www.stjarnhimlen.se/comp/ppcomp.html
  ##
  function &_getjdd($Y, $M=0, $D=0, $H=0, $I=0, $S=0)
  {
	if(func_num_args() < 6) list($JD) = _solar::_getjd($Y);
	else list($JD) = _solar::__getjd($Y,$M,$D,$H,$I,$S); // is KST

	return sprintf('%.13f',$JD-2451543.5); // another $D, $D + 1.5
  }
  ***/

  ## private, degress to valid
  ##
  function &_deg2valid($deg)
  {
	//if($deg<=360 && $deg>=0) return $deg;
	$deg = ($deg>=0) ? fmod($deg,360) : fmod($deg,360)+360.0;

	return (float)$deg; // float degress
  }

  ## private
  ##
  function &_moon2valid($moon)
  {
	if($moon < 1) $moon = 1;
	else if($moon > 12) $moon = 12;

	return (int)$moon;
  }

  ## private, degress to time(seconds)
  ##
  function &_deg2daytime($deg)
  {
	return sprintf('%.4f',$deg*240); // seconds
  }

  ## private, degress to angle
  ##
  function &_deg2angle($deg, $singed=FALSE)
  {
	if($singed) $singed = '+';
	if($deg <0) { $singed = '-'; $deg = abs($deg); }

	$time = sprintf('%.4f',$deg*3600);
	$degr = (int)$deg.chr(161).chr(198); //sprintf('%d',$deg);
	$time = sprintf('%.4f',$time-($degr*3600)); // fmod
	$mins = sprintf('%02d',$time/60).chr(161).chr(199);
	$secs = sprintf('%.4f',$time-($mins*60)).chr(161).chr(200); // fmod

	return $singed.$degr.$mins.$secs;
  }

  ## private, degress to solar time
  ##
  ## 1 solar year == 365.242190 days == 31556925.216 seconds
  ## 1 degress == 31556925.216 seconds / 360 degress == 87658.1256 seconds
  ##
  function &_deg2solartime($deg)
  {
	return sprintf('%.4f',$deg*87658.1256); // seconds
  }

  ## private, get sun's approximation to the Sun's geocentric apparent ecliptic longitude
  ##
  function &_sunl($D)
  {
	$g = sprintf('%.10f',357.529 + (0.98560028 * $D)); // default 357.529, fixed 357.550
	$q = sprintf('%.10f',280.459 + (0.98564736 * $D));

	## fixed
	##
	$g = _solar::_deg2valid($g); // to valid degress
	$q = _solar::_deg2valid($q); // to valid degress

	## convert
	##
	$deg2rad = array();
	$deg2rad['g'] = deg2rad($g); // radian
	$deg2rad['2g'] = deg2rad($g*2); // radian

	$sing = sin($deg2rad['g']); // degress
	$sin2g = sin($deg2rad['2g']); // degress

	## L is an approximation to the Sun's geocentric apparent ecliptic longitude
	##
	$L = sprintf('%.10f',$q + (1.915 * $sing) + (0.020 * $sin2g));
	$L = _solar::_deg2valid($L); // degress
	$atime = _solar::_deg2solartime(round($L)-$L); // float

	return array($L,$atime); // array, float degress, float seconds
  }

  ## private, get solar 24 terms
  ##
  function &_terms($year=0, $smoon=1, $length=12)
  {
	## mktime(7+9,36,19-64,3,20,2000), 2000-03-20 16:35:15(KST)
	##
	static $start = 953537715; // start base unix timestamp
	static $tyear = 31556940; // tropicalyear to seconds
	static $byear = 2000; // start base year

	static $tterms = array
	(
	-6418939, -5146737, -3871136, -2589569, -1299777,        0,
	 1310827,  2633103,  3966413,  5309605,  6660762,  8017383,
	 9376511, 10735018, 12089855, 13438199, 14777792, 16107008,
	17424841, 18731368, 20027093, 21313452, 22592403, 23866369
	);

	static $ffd = array // patch day, {YYYY}{idx}
	(
	190311 => 1440, 191914 => -480, 192223 => -240, 192912 => 1920,
	193116 => 1920, 193910 => -780, 19547  => 3600, 195422 => 3480,
	195513 => 2880, 195523 => 3420, 19565  => 2880, 195812 => 3240,
	195815 => 3120, 19603  => 3240, 196111 => 3480, 196215 => 2160,
	196519 => 2520, 196520 => 2400, 196810 => 1860, 198218 =>  660,
	19879  =>-3840, 198813 =>-3840, 199122 => -480, 20136  =>  360,
	20230  =>  600, 202311 => -400, 20303  => -420
	);

	$stime = $start + ($year - $byear) * $tyear;

	if($length < -12) $length = -12;
	else if($length > 12) $length = 12;

	$smoon = _solar::_moon2valid($smoon);
	$emoon = _solar::_moon2valid($smoon+$length);

	$sidx =  (min($smoon,$emoon) - 1) * 2;
	$eidx = ((max($smoon,$emoon) - 1) * 2) + 1;

	for($i=$sidx; $i<=$eidx; $i++)
	{
		$utime = $stime + $tterms[$i];
		list(,,$D) = _solar::_getjd($utime);
		list(,$atime) = _solar::_sunl($D); // ($utime-946727936)/86400;
		$utime += $atime + $ffd["$year$i"]; // re-fixed
		$terms[] = calendar::_date('nd',$utime);
	}

	return $terms; // array
  }

  ## private, get a Constellation of zodiac
  ##
  function &_constellation($y, $m, $d)
  {
	static $ffd = array // patch day
	(
	19030622 => -24, 19221222 =>   4, 19540420 => -61, 19550723 => -48,
	19551222 => -57, 19560320 => -48, 19580823 => -52, 19600219 => -55,
	19610221 => -59, 19620823 => -37, 19651023 => -42, 19870525 =>  64,
	19880722 =>  61, 20230621 =>   4, 20300218 =>   7
	);

	$horoscope = array // do not set `static' variable
	(
	array(chr(187).chr(234).chr(190).chr(231),'Aries'),
	array(chr(200).chr(178).chr(188).chr(210),'Taurus'),
	array(chr(189).chr(214).chr(181).chr(213).chr(192).chr(204),'Gemini'),
	array(chr(176).chr(212),'Cancer'),
	array(chr(187).chr(231).chr(192).chr(218),'Leo'),
	array(chr(195).chr(179).chr(179).chr(224),'Virgo'),
	array(chr(195).chr(181).chr(196).chr(170),'Libra'),
	array(chr(192).chr(252).chr(176).chr(165),'Scorpius'),
	array(chr(177).chr(195).chr(188).chr(246),'Sagittarius'),
	array(chr(191).chr(176).chr(188).chr(210),'Capricon'),
	array(chr(185).chr(176).chr(186).chr(180),'Aquarius'),
	array(chr(185).chr(176).chr(176).chr(237).chr(177).chr(226),'Pisces')
	);

	//list(,$nd) = _solar::_terms($y,$m,0);
	//$idx = ($m.$d<$nd) ? $m-2 : $m-1;
	//if($idx < 0) $idx += 12;

	$fk = sprintf('%d%02d%d',$y,$m,$d);
	//list(,,$D) = _solar::_getjd(mktime(23,59+(int)$ffd[$fk],59,$m,$d,$y));
	//list(,,$D) = _solar::_getjd(calendar::_mktime(23,59+(int)$ffd[$fk],59,$m,$d,$y));
	list(,,$D) = calendar::_getjd($y,$m,$d,23,59+(int)$ffd[$fk],59);
	list($L) = _solar::_sunl($D);

	return $horoscope[floor($L/30)];
  }
} // end of class

## public lunar
##
class lunar extends _solar
{
  ## private, time to moon time(h i s)
  ##
  function &_time2mtime($time, $singed=FALSE)
  {
	if($singed) $singed = '+';
	if($time<0) { $singed = '-'; $time = abs($time); }

	return $singed.calendar::_date('H i s',$time-date('Z'));
  }

  ## private, get moon's approximation to the Moon's geocentric apparent
  ## ecliptic longitude
  ##
  function &_moonl($T)
  {
	$lambda = 218.32 + (481267.883*$T)
	+ 6.29 * sin(deg2rad(134.9 + 477198.85*$T))
	- 1.27 * sin(deg2rad(259.2 - 413335.38*$T))
	+ 0.66 * sin(deg2rad(235.7 + 890534.23*$T))
	+ 0.21 * sin(deg2rad(269.9 + 954397.7*$T))
	- 0.19 * sin(deg2rad(357.5 + 35999.05*$T))
	- 0.11 * sin(deg2rad(186.6 + 966404.05*$T));

	return array(lunar::_deg2valid($lambda),$lambda);
  }

  ## private, get Moon's ecliptic
  ##
  function &_moone($T)
  {
	$beta = 5.13 * sin(deg2rad(93.3 + 483202.03*$T))
	+ 0.28 * sin(deg2rad(228.2 + 960400.87*$T))
	- 0.28 * sin(deg2rad(318.3 + 6003.18*$T))
	- 0.17 * sin(deg2rad(217.6 - 407332.2*$T));

	return $beta; // float
  }

  ## public, get moon positon
  ##
  ## http://user.chollian.net/~kimdbin/re/moonpos.html
  ##
  function &moon($utime=0)
  {
	//static $D, $J, $JD, $T, $L, $RA, $e, $d, $lambda;
	//static $y, $b, $l, $m, $n;

	/***
	if($utime<-2142664200 || $utime>2146229999)
	{
		echo "\nerror: invalid input $utime, 1902.02.08 00:00:00 <= utime <= 2038.01.04 23:59:59\n";
		return -1;
	}
	***/

	if($utime == '') $utime = time();

	list($JD,$J,$D,$T) = lunar::_getjd($utime);
	list($L,$lambda) = lunar::_moonl($T);
	$e = lunar::_moone($T); // is beta, Moon's ecliptic

	$y = deg2rad($lambda);
	$b = deg2rad($e);

	$l = cos($b) * cos($y);
	$m = 0.9175 * cos($b) * sin($y) - (0.3978 * sin($b));
	$n = 0.3978 * cos($b) * sin($y) + (0.9175 * sin($b));

	$RA = rad2deg(atan2($m,$l));
	$RA = lunar::_deg2valid($RA); // Moon's right ascension
	$d = rad2deg(asin($n)); // Moon's declination

	$mtime = lunar::_deg2daytime($L); // seconds
	$dtime = lunar::_deg2daytime($RA); // seconds

	return array
	(
	'JD'=> sprintf('%.10f',$JD),	/*** Julian Date ***/
	'J' => 'J'.$J,		/*** Julian Date Jxxxx.xxxx format ***/
	'L' => $L,		/*** Moon's geocentric apparent ecliptic longitude ***/
	'e' => $e,		/*** Moon's ecliptic ***/
	'RA'=> $RA,		/*** Moon's right ascension  ***/
	'd' => $d,		/*** Moon's declination ***/
	'mtime' => $mtime,	/*** seconds ***/
	'dtime' => $dtime,	/*** seconds ***/
	'utime' => $utime,
	'date'  => calendar::_date('D, d M Y H:i:s T',$utime),	/*** KST date ***/
	'gmdate'=> calendar::_date('D, d M Y H:i:s ',$utime-date('Z')).'GMT', /*** GMT date ***/
	'_L'    => lunar::_deg2angle($L),		/*** angle ***/
	'_e'    => lunar::_deg2angle($e,1),		/*** angle ***/
	'_RA'   => lunar::_deg2angle($RA),		/*** angle ***/
	'_d'    => lunar::_deg2angle($d,1),
	'_mtime'=> lunar::_time2mtime($mtime),
	'_dtime'=> lunar::_time2mtime($dtime)
	);
  }

  ## private, get moon's degress - sun's degress
  ##
  function &_gettd($utime)
  {
	list(,,$D,$T) = lunar::_getjd($utime);
	list($s) = lunar::_sunl($D);
	list($l) = lunar::_moonl($T);

	return lunar::_deg2valid($l-$s); // float
  }

  ## private, get unix timestamp of conjunction, new moon day(xxxx-xx-01)
  ##
  ## - http://www.kao.re.kr/html/study/faq/index.html?f=3&idx=79
  ## - http://www.kao.re.kr/html/study/faq/index.html?f=3&idx=43
  ##
  ## 1 solar year == 365.242190 days == 31556925.216 seconds
  ## 1 degress == 31556925.216 seconds / 360 degress == 87658.1256 seconds
  ##
  ## 1 (new moon) moon == 29.53059 dayes = 2551442.976 seconds
  ## 1 degress == 2551442.976 seconds / 360 degress = 7087.3416 seconds
  ##
  ## sun : moon == 1 : 12.3682659235728 == 0.0808520779048 : 1
  ##
  ## move to 1 degress = 7710.7736596978271 seconds (sun and moon => same line)
  ##     7087.3416 +
  ##      573.0262951811299 +
  ##       46.3303666594836 +
  ##        3.7459064145105 +
  ##        0.3028643172501 +
  ##        0.0244872093729 +
  ##        0.0019798417599 +
  ##        0.0001600743202
  ##
  ## move to 86400 seconds :
  ##     avg(13.2433041906) std(1.16287866011) max(15.2504690629) min(11.8423079447)
  ## move to 1 degress :
  ##     mix(7295.8751286879124083279675026639 seconds)
  ##     avg(6524.0516080062621468182286547561 seconds)
  ##     max(5665.3995128704809432711052144198 seconds)
  ##
  function &_newmoon($_y, $_m=0, $_d=0, $ctime=0)
  {
	static $unit = 5665; // see above comments
	static $ffx = array
	(
	19310517=>2640, 19321030=>-840, 19341008=> 840, 19530612=>-600,
	19550222=>4020, 19580218=>2700, 19860311=>-540, 19950727=>1140,
	20120619=> 780, 20150815=>-540, /*20170226=> 480,*/ 20350109=> 540,
	);

	$utime = $ctime = (func_num_args()<2) ? $_y : calendar::_mktime(23,59,59,$_m,$_d,$_y);
	$td = lunar::_gettd($utime);

	//echo $td."\n";
	if($td > 359.5)
	{
		//echo $td."\n";
		$utime += 86400;
		$td = lunar::_gettd($utime);
	}

	while($td > 0.000177) // 1/$unit
	{
		//echo $td."\n";
		$utime -= $td * $unit;
		$otd = $td;
		$td = lunar::_gettd($utime);
		if($td > $otd) break;
	}

	$utime += (int)$ffx[calendar::_date('Ymd',$utime)];
	if($ctime < $utime) $utime -= 2592000; // 86400 * 30;

	return (int)$utime;
  }

  ## private, get tdm
  ##
  function &_gettm($utime)
  {
	list(,,$D,$T) = lunar::_getjd($utime);
	list($s) = lunar::_sunl($D);
	list($l) = lunar::_moonl($T);

	$tm = lunar::_deg2valid($s-180) - $l; // float

	//echo "$s $l => $tm\n"; // debug
	if($tm > 180.0) $tm -= 360.0; // patch 2005.02.25

	return $tm;
  }

  ## private, get unix timestamp of full moon day(xxxx-xx-15)
  ##
  function &_fullmoon($_y, $_m=0, $_d=0)
  {
	static $unit = 5665; // see above comments
	static $ffx = array
	(
	19031006=>2000, 19131213=>  120, 19280801=>2100, 19360506=> 400,
	19380712=> 300, 19450625=>  600, 19500828=>-700, 19550308=>2700,
	19560524=>1900, 19581027=> 3000, 19810617=> 500, 19990501=>-900,
	20211021=>-300, 20261125=>-1100, 20280210=> 700, 20320425=> 600,
	);

	$utime = (func_num_args()<2) ? $_y : calendar::_mktime(23,59,59,$_m,$_d,$_y);

	$td = lunar::_gettm($utime);
	$ta = abs($td);

	while($ta > 0.000177) // 1/$unit
	{
		//echo $td.' '.date('Y-m-d H:i:s',$utime)."\n"; // debug
		$ota = $ta;
		$ptime = $utime + ($td * $unit); // pre-test time
		$td = lunar::_gettm($ptime);
		$ta = abs($td);

		if($ta > $ota) break;
		$utime = $ptime;
	}

	$utime += (int)$ffx[calendar::_date('Ymd',$utime)];

	return (int)$utime;
  }

  ## private, get solar eclipse idx name
  ##
  ## Solar Eclipses: T(Total), A(Annular), H(Hybrid(Annular/Total)), P(Partial)
  ## A 104 0.010582273616323 1.06751983653440(1.067743)
  ## T  91 0.014674627401046 1.04166992331860
  ## H   6 0.210833791736160 0.96121766199154(0.964180)
  ## P 106 0.829402137331320 1.59530999819400
  ##
  function &_solareclipse($utime)
  {
	list(,,,$T) = lunar::_getjd($utime);
	$e = lunar::_moone($T); // is beta, Moon's ecliptic
	$e = abs($e);

	if($e < 0.014674) $r = 'A';
	else if($e < 0.210833) $r = 'AT';
	else if($e < 0.829402) $r = 'ATH';
	else if($e < 0.964180) $r = 'PATH';
	else if($e < 1.041670) $r = 'PAT';
	else if($e < 1.067743) $r = 'PA';
	else if($e < 1.595310) $r = 'P';
	else $r = 'N';

	return $r;
  }

  ## public, get solar eclipse exists at new moon
  ##
  function &solareclipse($y, $m, $d)
  {
	list($ymd0,$y,$m,$d) = explode(' ',calendar::_date('Ymd Y n j',calendar::_mktime(12,0,0,$m,$d,$y))); // refixed

	$utime = lunar::_newmoon($y,$m,$d);
	$ymd1 = calendar::_date('Ymd',$utime);

	if($ymd0 == $ymd1) $r = lunar::_solareclipse($utime);
	else $r = 'N';

	return $r;
  }

  ## private, get lunar eclipse idx name
  ##
  ## Lunar Eclipses: t(Total), p(Umbral(Partial)), n(Penumbral)
  ## t 114 0.010630181434784 0.52538271749109(0.527908)
  ## p  85 0.294681791935650 1.14183526374750
  ## n 111 0.832900661071600 1.57436507046800(1.578244)
  ##
  function &_lunareclipse($utime)
  {
	list(,,,$T) = lunar::_getjd($utime);
	$e = lunar::_moone($T); // is beta, Moon's ecliptic
	$e = abs($e);

	if($e < 0.294681) $r = 't';
	else if($e < 0.527908) $r = 'tp';
	else if($e < 0.832900) $r = 'p';
	else if($e < 1.141836) $r = 'np';
	else if($e < 1.578244) $r = 'n';
	else $r = 'N';

	return $r;
  }

  ## public, get lunar eclipse exists at full moon
  ##
  function &lunareclipse($y, $m, $d)
  {
	//list($ymd0,$y,$m,$d) = explode(' ',calendar::_date('Ymd Y n j',calendar::_mktime(12,0,0,$m,$d,$y))); // refixed
	list($ymd0,$y,$m,$d) = explode(' ',calendar::date('Ymd Y n j',calendar::mkjd(12,0,0,$m,$d,$y))); // refixed

	$utime = lunar::_fullmoon($y,$m,$d);
	$ymd1 = calendar::_date('Ymd',$utime);

	if($ymd0 == $ymd1) $r = lunar::_lunareclipse($utime);
	else $r = 'N';

	return $r;
  }

  ## public, from solar date to lunar date
  ##
  function &tolunar($_y, $_m, $_d)
  {
	static $notminus = array(19651024=>1,2033923=>1,20331023=>1,20331122=>1); // do not minus,  // patch san2@2011.04.11
	static $notleap = array(1965925=>1,1985121=>1,1985220=>1,2033825=>1,2034219=>1); // patch san2@2011.04.11
	static $dominus = array(1985121=>1,1985220=>1,2034219=>1); // patch san2@2011.04.11

	$_y = (int)$_y; // refixed
	$_m = (int)$_m; // refixed
	$_d = (int)$_d; // refixed

	/***
	if($_y<1902 || $_y>2038)
	{
		echo "\nerror: tolunar() invalid input solar arguments, 1902-01-10 <= solar date <= 2038-01-18\n";
		return -1;
	}
	***/

	## check lunar or solar eclipse of current date
	##
	$eclipse['c'] = lunar::lunareclipse($_y,$_m,$_d);
	if($eclipse['c'] == 'N') $eclipse['c'] = lunar::solareclipse($_y,$_m,$_d);

	## get current new moon
	##
	$utime = lunar::_newmoon($_y,$_m,$_d,&$ctime);
	list($y,$m,$j,$z,$t,$nd,$ymd0,$his0) = explode(' ',calendar::_date('Y n j z t nd Y-m-d H:i:s',$utime));
	$eclipse['u'] = lunar::_solareclipse($utime);

	## get lunar days
	##
	$tmp = $ctime - $utime;
	$age = sprintf('%.2f',($tmp-43200)/86400); // age of Moon at 12:00:01
	$d = ceil($tmp/86400);
	$leap = 0; // leap month

	## get current full moon
	##
	$ftime = lunar::_fullmoon($utime+1382400); // 1382400 = 86400 * 16, patch san2@2007.09.27
	list($ymd1,$his1) = explode(' ',calendar::_date('Y-m-d H:i:s Y n j',$ftime));
	$eclipse['f'] = lunar::_lunareclipse($ftime);

	## get next new moon
	##
	$ntime = lunar::_newmoon($_y,$_m,$_d+31-$d); // 86400*31
	list($y2,$m2,$z2,$nd2,$ymd2,$his2) = explode(' ',calendar::_date('Y n z nd Y-m-d H:i:s',$ntime));
	$eclipse['n'] = lunar::_solareclipse($ntime);

	## get solar term(tt) and day term(dt)
	##
	if($y < $y2) // defference year
	{
		$tt = array_merge(lunar::_terms($y,$m,0),lunar::_terms($y2,$m2,0));
		$dt = $t - $j + $z2 + 1; // day term
	} else // same year
	{
		$tt = lunar::_terms($y,$m,$m2-$m);
		$dt = $z2 - $z;
	}

	//echo " $nd, $tt[1], $nd2, $tt[3], $tt[5] "; // debug
	//if($nd<=$tt[1] && !$notminus[$y.$nd]) $m--;
	if($nd <= $tt[1]) { if(!$notminus[$y.$nd]) $m--; } // patch san2@2011.04.11
	else
	{
		$k = sizeof($tt) - 1; // 1 or 3 or 5 but this case 3 or 5
		if($nd2-1<$tt[$k] && $k==3 && !$notleap[$y.$nd])
		{ $leap = 1; $m--; }
		else if($dominus[$y.$nd]) $m--;
		# else do not minus
	}

	if($m < 1) { $m += 12; $y--; } //date('Y',$utime-3456000)

	return array
	(
	sprintf('%d-%02d-%02d',$y,$m,$d),		// YYYY-MM-DD
	array($y,$m,$d,$leap,$dt,$age,$eclipse['c']),	// YYYY,M,D,leap,term,age,eclipse
	array($ymd0,$his0,$utime,$eclipse['u']),	// current new moon
	array($ymd1,$his1,$ftime,$eclipse['f']),	// current full moon
	array($ymd2,$his2,$ntime,$eclipse['n']),	// next new moon
	);
  }

  ## private, get new moon informations, use at tosolar()
  ##
  function &_newmooninfo($_y, $_o, $_m, $_leap, $_stop=0, $_d=15)
  {
	//static $_d = 15; // good idea, patch san2@2010.05.17 disabled

	if($_m > 12) { $_m -= 12; $_y++; }
	else if($_m < 1) { $_m += 12; $_y--; }

	$_l = (int)(boolean)$_leap;
	$_p = $_stop ? $_m : $_m + 1 + $_l; // pre test month

	if($_p > 12) { $_p -= 12; $_y++; }
	list(,list($y,$m,,$leap,$t),$newmoon,,$nextmoon) = lunar::tolunar($_y,$_p,$_d);

	if($leap==$_l && $m==$_o) $newmoon[] = $t; // add term
	else if(!$_stop)
	{
		$output = $y.sprintf('%02d',$m);
		$input = $_y.sprintf('%02d',$_y,$_m);
		if($output < $input) { $ymd = $nextmoon[0]; $j = 1; } // patch san2@2010.05.17
		else { $ymd = $newmoon[0]; $j = -2; }

		list($_y,$_m,$_d) = explode('-',$ymd);
		$_d += $j; // change static $_d
		$newmoon = lunar::_newmooninfo($_y,$_o,$_m,$_leap,1,$_d);
	}

	return $newmoon; // array
  }

  ## public, from lunar date to solar date
  ##
  function &tosolar($_y, $_m, $_d, $_leap=0)
  {
	$_y = (int)$_y; // refixed
	$_m = (int)$_m; // refixed
	$_d = (int)$_d; // refixed

	/***
	if($_y<1901 || $_y>2037)
	{
		echo "\nerror: tosolar() invalid input lunar arguments, 1901-12-01 <= lunar date <= 2037-12-14\n";
		return -1;
	}
	***/

	if(!$newmoon = lunar::_newmooninfo($_y,$_m,$_m,$_leap)) return; // false

	list(,,$utime,,$term) = $newmoon;

	## check input day
	##
	if($_d > 29)
	{
		if($term)
		{
			if($_d > $term) $ck = 0; // is false
			else $ck = 1; // ture valid input day
		} else
		{
			//$_g = getdate($utime);
			//$_t = lunar::tolunar($_g['year'],$_g['mon'],$_g['mday']);
			list($_gy,$_gn,$_gd) = explode(' ',calendar::_date('Y n d',$utime));
			$_t = lunar::tolunar($_gy,$_gn,$_gd);
			if($_d > $_t[1][2]) $ck = 0; // is false
			else $ck = 1; // true
		}
	} else $ck = 1;

	$utime += 86400 * ($_d-1);
	list($ymd,$y,$n,$j,$w) = explode(' ',calendar::_date('Y-m-d Y n j w',$utime));

	return array
	(
	$ymd,		// string YYYY-MM-DD
	$ck,		// check input day is valid ?
	$y,$n,$j,	// YYYY,M,D
	$w,		// weekday idx,0(Sunday) through 6(Saturday)
	$newmoon,	// new moon infomation
	);
  }

  ## public, get a Constellation of zodiac
  ##
  function &zodiac($y, $m, $d, $lunar=0, $leap=0)
  {
	if($lunar) list(,,$y,$m,$d) = lunar::tosolar($y,$m,$d,$leap);

	return lunar::_constellation($y,$m,$d);
  }

  ## public, get easter day
  ##
  function &easter($y, $debug=array())
  {
	$p = _solar::_terms($y,3,0);
	$m = substr($p[1],0,1);
	$d = substr($p[1],-2);

	list(,,,$f,$n) = lunar::tolunar($y,$m,$d); // lunar
	$full = str_replace('-','',$f[0]);
	$curr = sprintf('%d%02d%02d',$y,$m,$d);

	if($curr >= $full)
	{
		list($ty,$tm,$td) = explode('-',$n[0]);
		list(,,,$f) = lunar::tolunar($ty,(int)$tm,$td); // lunar
	}

	list($ty,$tm,$td) = explode('-',$f[0]);
	$jd = calendar::mkjd(21,0,0,(int)$tm,$td,$ty);
	$w = 7 - calendar::date('w',$jd);
	$r = calendar::date('m/d',$jd+$w);

	if(func_num_args() > 1)
	{
		list(,$fm,$fd) = explode('-',$f[0]);
		$debug[0] = "$m/$d";
		$debug[1] = "$fm/$fd";
	}

	return $r;
  }
} // end of class
?>