Remove phase of moon feature

The computation never really worked before and it seems like the feature
is not very helpful, sometimes even confusing (see GitHub issue #21).

The macro ISLEAP is moved to calcurse.h.

Signed-off-by: Lars Henriksen <LarsHenriksen@get2net.dk>
Signed-off-by: Lukas Fleischer <lfleischer@calcurse.org>

4 files changed, 2 insertions, 185 deletions

diff --git a/src/calcurse.h b/src/calcurse.h
index 10e60aa..133b6b9 100644
--- a/src/calcurse.h
+++ b/src/calcurse.h
@@ -302,6 +302,8 @@ struct date {
 	unsigned yyyy;
 };
 
+#define ISLEAP(y) ((((y) % 4) == 0 && ((y) % 100) != 0) || ((y) % 400) == 0)
+
 /* Appointment definition. */
 struct apoint {
 	long start;		/* seconds since 1 jan 1970 */
@@ -740,7 +742,6 @@ void ui_calendar_change_day(int);
 void ui_calendar_move(enum move, int);
 long ui_calendar_start_of_year(void);
 long ui_calendar_end_of_year(void);
-const char *ui_calendar_get_pom(time_t);
 
 /* config.c */
 void config_load(void);
diff --git a/src/ui-calendar.c b/src/ui-calendar.c
index 9ea31e1..a2a0e8b 100644
--- a/src/ui-calendar.c
+++ b/src/ui-calendar.c
@@ -44,29 +44,6 @@
 
 #include "calcurse.h"
 
-#ifndef M_PI
-#define	M_PI	  3.14159265358979323846
-#endif
-
-#define	EPOCH	  90
-#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 */
-
-#define ISLEAP(y) ((((y) % 4) == 0 && ((y) % 100) != 0) || ((y) % 400) == 0)
-
-enum pom {
-	NO_POM,
-	FIRST_QUARTER,
-	FULL_MOON,
-	LAST_QUARTER,
-	NEW_MOON,
-	MOON_PHASES
-};
-
 static struct date today, slctd_day;
 static unsigned ui_calendar_view, week_begins_on_monday;
 static pthread_mutex_t date_thread_mutex = PTHREAD_MUTEX_INITIALIZER;
@@ -780,161 +757,3 @@ long ui_calendar_end_of_year(void)
 
 	return (long)(timer - 1);
 }
-
-/*
- * The pom, potm, dotr, adj360 are used to compute the current
- * phase of the moon.
- * The code is based on the OpenBSD version of pom(6).
- * Below is reported the copyright notice.
- */
-/*
- * 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. 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.
- */
-
-/*
- * dtor --
- *	convert degrees to radians
- */
-static double dtor(double deg)
-{
-	return deg * M_PI / 180;
-}
-
-/*
- * adj360 --
- *	adjust value so 0 <= deg <= 360
- */
-static void adj360(double *deg)
-{
-	for (;;)
-		if (*deg < 0.0)
-			*deg += 360.0;
-		else if (*deg > 360.0)
-			*deg -= 360.0;
-		else
-			break;
-}
-
-/*
- * 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, IX 1998
- *
- */
-
-/*
- * potm --
- *	given number of days since January 1st 1990, 00:00
- *	(incl. hours and minutes as a fraction of a day),
- *	return phase of the moon as a percentage.
- */
-static double potm(double days)
-{
-	double N, Msol, Ec, LambdaSol, l, Mm, Ev, Ac, A3, Mmprime;
-	double A4, lprime, V, ldprime, D, Nm;
-
-	N = 360.0 * days / 365.242191;	/* sec 46 #3 */
-	adj360(&N);
-	Msol = N + EPSILONg - RHOg;	/* sec 46 #4 */
-	adj360(&Msol);
-	Ec = 360 / M_PI * ECCEN * sin(dtor(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(dtor(2 * (l - LambdaSol) - Mm));	/* sec 65 #7 */
-	Ac = 0.1858 * sin(dtor(Msol));	/* sec 65 #8 */
-	A3 = 0.37 * sin(dtor(Msol));
-	Mmprime = Mm + Ev - Ac - A3;	/* sec 65 #9 */
-	Ec = 6.2886 * sin(dtor(Mmprime));	/* sec 65 #10 */
-	A4 = 0.214 * sin(dtor(2 * Mmprime));	/* sec 65 #11 */
-	lprime = l + Ev + Ec - Ac + A4;	/* sec 65 #12 */
-	V = 0.6583 * sin(dtor(2 * (lprime - LambdaSol)));	/* sec 65 #13 */
-	ldprime = lprime + V;	/* sec 65 #14 */
-	D = ldprime - LambdaSol;	/* sec 67 #2 */
-	return 50.0 * (1 - cos(dtor(D)));	/* sec 67 #3 */
-}
-
-static double pom(time_t tmpt)
-{
-	struct tm *GMT;
-	double days;
-	int cnt;
-
-	GMT = gmtime(&tmpt);
-	days = (GMT->tm_yday + 1) + ((GMT->tm_hour + (GMT->tm_min / 60.0) +
-				      (GMT->tm_sec / 3600.0)) / 24.0);
-	for (cnt = EPOCH; cnt < GMT->tm_year; ++cnt)
-		days += ISLEAP(cnt + TM_YEAR_BASE) ? 366 : 365;
-	/* Selected time could be before EPOCH */
-	for (cnt = GMT->tm_year; cnt < EPOCH; ++cnt)
-		days -= ISLEAP(cnt + TM_YEAR_BASE) ? 366 : 365;
-
-	return potm(days);
-}
-
-/*
- * Return a pictogram representing the current phase of the moon.
- * Careful: date is the selected day in calendar at 00:00,
- * and so represents the phase of the moon at midnight.
- */
-const char *ui_calendar_get_pom(time_t date)
-{
-	const char *pom_pict[MOON_PHASES] =
-	    { "   ", "|) ", "(|)", "(| ", " | " };
-	enum pom phase = NO_POM;
-	const double half = 50.0;
-
-	date += DAYINSEC / 2;				/* adjust to noon */
-	double pom_n_b = pom(date - DAYINSEC);	 	/* noon before */
-	double pom_m_b = pom(date - DAYINSEC / 2);	/* midnight before */
-	double pom_n   = pom(date); 			/* noon */
-	double pom_m_a = pom(date + DAYINSEC / 2);	/* midnight after */
-	double pom_n_a = pom(date + DAYINSEC);	 	/* noon after */
-
-	if (pom_n > pom_n_b && pom_n > pom_n_a)
-		phase = FULL_MOON;
-	else if (pom_n < pom_n_b && pom_n < pom_n_a)
-		phase = NEW_MOON;
-	else if (pom_m_b < half && half < pom_m_a)
-		phase = FIRST_QUARTER;
-	else if (pom_m_b > half && half > pom_m_a)
-		phase = LAST_QUARTER;
-	return pom_pict[phase];
-}
diff --git a/src/ui-day.c b/src/ui-day.c
index 1cc9eb0..6a06941 100644
--- a/src/ui-day.c
+++ b/src/ui-day.c
@@ -916,7 +916,6 @@ static char *fmt_day_heading(time_t date)
 
 	localtime_r(&date, &tm);
 	string_init(&s);
-	string_printf(&s, "%s ", ui_calendar_get_pom(date));
 	string_catftime(&s, conf.day_heading, &tm);
 	return string_buf(&s);
 }
diff --git a/src/utils.c b/src/utils.c
index e0e35bc..11d4582 100644
--- a/src/utils.c
+++ b/src/utils.c
@@ -51,8 +51,6 @@
 #include "calcurse.h"
 #include "sha1.h"
 
-#define ISLEAP(y) ((((y) % 4) == 0 && ((y) % 100) != 0) || ((y) % 400) == 0)
-
 #define FS_EXT_MAXLEN 64
 
 enum format_specifier {