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+/*
+ This file is part of libkholidays.
+ Copyright (c) 2004 Allen Winter <winter@kde.org>
+
+ Copyright (c) 1989, 1993
+ The Regents of the University of California. All rights reserved.
+
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU General Public License as
+ published by the Free Software Foundation; either version 2 of the
+ License, or (at your option) any later version.
+
+ This library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+
+ In addition, as a special exception, the copyright holders give
+ permission to link the code of this program with any edition of
+ the Qt library by Trolltech AS, Norway (or with modified versions
+ of Qt that use the same license as Qt), and distribute linked
+ combinations including the two. You must obey the GNU General
+ Public License in all respects for all of the code used other than
+ Qt. If you modify this file, you may extend this exception to
+ your version of the file, but you are not obligated to do so. If
+ you do not wish to do so, delete this exception statement from
+ your version.
+*/
+
+#include "config.h"
+
+#include <kglobal.h>
+#include <klocale.h>
+#include <kdebug.h>
+
+#include "lunarphase.h"
+
+LunarPhase::LunarPhase( Hemisphere hemisphere )
+{
+ mHemisphere = hemisphere;
+}
+
+LunarPhase::~LunarPhase()
+{
+}
+
+void LunarPhase::setHemisphere( Hemisphere hemisphere )
+{
+ mHemisphere = hemisphere;
+}
+
+LunarPhase::Hemisphere LunarPhase::hemisphere() const
+{
+ return( mHemisphere );
+}
+
+QString LunarPhase::hemisphereStr() const
+{
+ return hemisphereName( mHemisphere );
+}
+
+QString LunarPhase::hemisphereName( LunarPhase::Hemisphere hemisphere )
+{
+ switch( hemisphere ) {
+ case Northern:
+ default:
+ return( i18n( "Northern" ) );
+ break;
+ case Southern:
+ return( i18n( "Southern" ) );
+ break;
+ }
+}
+
+QString LunarPhase::phaseStr( const QDate &date ) const
+{
+ return phaseName( phase( date ) );
+}
+
+QString LunarPhase::phaseName( LunarPhase::Phase phase )
+{
+ switch ( phase ) {
+ case New:
+ return( i18n( "New Moon" ) );
+ break;
+ case Full:
+ return( i18n( "Full Moon" ) );
+ break;
+ case FirstQ:
+ return( i18n( "First Quarter Moon" ) );
+ break;
+ case LastQ:
+ return( i18n( "Last Quarter Moon" ) );
+ break;
+ default:
+ case None:
+ return( QString::null );
+ break;
+ }
+}
+
+LunarPhase::Phase LunarPhase::phase( const QDate &date ) const
+{
+ Phase retPhase = None;
+
+ // compute percent-full for the middle of today and yesterday.
+ QTime noontime( 12, 0, 0 );
+ QDateTime today( date, noontime );
+ double todayPer = percentFull( today.toTime_t() );
+ QDateTime yesterday( date.addDays(-1), noontime );
+ double yesterdayPer = percentFull( yesterday.toTime_t() );
+
+ if ( ( todayPer < 0.50 ) && ( yesterdayPer > 0.50 ) ) {
+ retPhase = New;
+ } else if ( ( todayPer > 99.50 ) && ( yesterdayPer < 99.50 ) ) {
+ retPhase = Full;
+ } else {
+ // compute percent-full for the start of today.
+ QTime sqt( 0, 0, 0 );
+ QDateTime start( date, sqt );
+ double startPer = percentFull( start.toTime_t() );
+ // compute percent-full for the end of today.
+ QTime eqt( 23, 59, 59 );
+ QDateTime end( date, eqt );
+ double endPer = percentFull( end.toTime_t() );
+
+ if ( ( startPer <= 50 ) && ( endPer > 50 ) ) {
+ if ( mHemisphere == Northern ) {
+ retPhase = FirstQ;
+ } else {
+ retPhase = LastQ;
+ }
+ }
+ if ( ( endPer <= 50 ) && ( startPer > 50 ) ) {
+ if ( mHemisphere == Northern ) {
+ retPhase = LastQ;
+ } else {
+ retPhase = FirstQ;
+ }
+ }
+ // Note: if you want to support crescent and gibbous phases then please
+ // read the source for the original BSD 'pom' program.
+ }
+ return( retPhase );
+}
+
+/*
+ * Copyright (c) 1989, 1993
+ * The Regents of the University of California. All rights reserved.
+ *
+ * This code is derived from software posted to USENET.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by the University of
+ * California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#if HAVE_SYS_CDEFS_H
+#include <sys/cdefs.h>
+#endif
+
+/*
+ * Phase of the Moon. Calculates the current phase of the moon.
+ * Based on routines from `Practical Astronomy with Your Calculator',
+ * by Duffett-Smith. Comments give the section from the book that
+ * particular piece of code was adapted from.
+ *
+ * -- Keith E. Brandt VIII 1984
+ *
+ * Updated to the Third Edition of Duffett-Smith's book, Paul Janzen, IX 1998
+ *
+ */
+
+
+#include <ctype.h>
+#if HAVE_ERR_H
+#include <err.h>
+#endif
+#include <math.h>
+#include <string.h>
+#include <stdlib.h>
+#include <time.h>
+#include <unistd.h>
+
+#ifndef PI
+#define PI 3.14159265358979323846
+#endif
+
+/*
+ * The EPOCH in the third edition of the book is 1990 Jan 0.0 TDT.
+ * In this program, we do not bother to correct for the differences
+ * between UTC (as shown by the UNIX clock) and TDT. (TDT = TAI + 32.184s;
+ * TAI-UTC = 32s in Jan 1999.)
+ */
+#define EPOCH_MINUS_1970 (20 * 365 + 5 - 1) /* 20 years, 5 leaps, back 1 day to Jan 0 */
+#define EPSILONg 279.403303 /* solar ecliptic long at EPOCH */
+#define RHOg 282.768422 /* solar ecliptic long of perigee at EPOCH */
+#define ECCEN 0.016713 /* solar orbit eccentricity */
+#define lzero 318.351648 /* lunar mean long at EPOCH */
+#define Pzero 36.340410 /* lunar mean long of perigee at EPOCH */
+#define Nzero 318.510107 /* lunar mean long of node at EPOCH */
+
+/*
+ * percentFull --
+ * return phase of the moon as a percentage of full
+ */
+double LunarPhase::percentFull( uint tmpt ) const
+{
+ double N, Msol, Ec, LambdaSol, l, Mm, Ev, Ac, A3, Mmprime;
+ double A4, lprime, V, ldprime, D, Nm;
+
+ double days;
+ days = ( tmpt - EPOCH_MINUS_1970 * 86400 ) / 86400.0;
+
+ N = 360 * days / 365.242191; /* sec 46 #3 */
+ adj360(&N);
+ Msol = N + EPSILONg - RHOg; /* sec 46 #4 */
+ adj360(&Msol);
+ Ec = 360 / PI * ECCEN * sin(degreesToRadians(Msol)); /* sec 46 #5 */
+ LambdaSol = N + Ec + EPSILONg; /* sec 46 #6 */
+ adj360(&LambdaSol);
+ l = 13.1763966 * days + lzero; /* sec 65 #4 */
+ adj360(&l);
+ Mm = l - (0.1114041 * days) - Pzero; /* sec 65 #5 */
+ adj360(&Mm);
+ Nm = Nzero - (0.0529539 * days); /* sec 65 #6 */
+ adj360(&Nm);
+ Ev = 1.2739 * sin(degreesToRadians(2*(l - LambdaSol) - Mm)); /* sec 65 #7 */
+ Ac = 0.1858 * sin(degreesToRadians(Msol)); /* sec 65 #8 */
+ A3 = 0.37 * sin(degreesToRadians(Msol));
+ Mmprime = Mm + Ev - Ac - A3; /* sec 65 #9 */
+ Ec = 6.2886 * sin(degreesToRadians(Mmprime)); /* sec 65 #10 */
+ A4 = 0.214 * sin(degreesToRadians(2 * Mmprime)); /* sec 65 #11 */
+ lprime = l + Ev + Ec - Ac + A4; /* sec 65 #12 */
+ V = 0.6583 * sin(degreesToRadians(2 * (lprime - LambdaSol))); /* sec 65 #13 */
+ ldprime = lprime + V; /* sec 65 #14 */
+ D = ldprime - LambdaSol; /* sec 67 #2 */
+ return(50.0 * (1 - cos(degreesToRadians(D)))); /* sec 67 #3 */
+}
+
+/*
+ * degreesToRadians --
+ * convert degrees to radians
+ */
+double LunarPhase::degreesToRadians( double degree ) const
+{
+ return( degree * PI / 180 );
+}
+
+/*
+ * adj360 --
+ * adjust value so 0 <= degree <= 360
+ */
+void LunarPhase::adj360( double *degree ) const
+{
+ for( ;; )
+ if( *degree < 0 )
+ *degree += 360;
+ else if( *degree > 360 )
+ *degree -= 360;
+ else
+ break;
+}