/* $calcurse: calendar.c,v 1.37 2010/03/29 11:48:05 culot Exp $ */ /* * Calcurse - text-based organizer * * Copyright (c) 2004-2010 Frederic Culot * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * - Redistributions of source code must retain the above * copyright notice, this list of conditions and the * following disclaimer. * * - 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. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT * OWNER 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. * * Send your feedback or comments to : calcurse@culot.org * Calcurse home page : http://culot.org/calcurse * */ #include #include #include #include #include #include #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 { CAL_MONTH_VIEW, CAL_WEEK_VIEW, CAL_VIEWS }; enum pom { NO_POM, FIRST_QUARTER, FULL_MOON, LAST_QUARTER, NEW_MOON, MOON_PHASES }; static struct date today, slctd_day; static unsigned calendar_view, week_begins_on_monday; static pthread_mutex_t date_thread_mutex = PTHREAD_MUTEX_INITIALIZER; static pthread_t calendar_t_date; static void draw_monthly_view (struct window *, struct date *, unsigned); static void draw_weekly_view (struct window *, struct date *, unsigned); static void (*draw_calendar[CAL_VIEWS]) (struct window *, struct date *, unsigned) = {draw_monthly_view, draw_weekly_view}; /* Switch between calendar views (monthly view is selected by default). */ void calendar_view_next (void) { calendar_view++; if (calendar_view == CAL_VIEWS) calendar_view = 0; } void calendar_view_prev (void) { if (calendar_view == 0) calendar_view = CAL_VIEWS; calendar_view--; } void calendar_set_view (int view) { calendar_view = (view < 0 || view >= CAL_VIEWS) ? CAL_MONTH_VIEW : view; } int calendar_get_view (void) { return (int)calendar_view; } /* Thread needed to update current date in calendar. */ /* ARGSUSED0 */ static void * calendar_date_thread (void *arg) { time_t actual, tomorrow; for (;;) { tomorrow = (time_t) (get_today () + DAYINSEC); while ((actual = time (NULL)) < tomorrow) (void)sleep (tomorrow - actual); calendar_set_current_date (); calendar_update_panel (&win[CAL]); } return (void *)0; } /* Launch the calendar date thread. */ void calendar_start_date_thread (void) { pthread_create (&calendar_t_date, NULL, calendar_date_thread, NULL); } /* Stop the calendar date thread. */ void calendar_stop_date_thread (void) { if (calendar_t_date) pthread_cancel (calendar_t_date); } /* Set static variable today to current date */ void calendar_set_current_date (void) { time_t timer; struct tm *tm; timer = time (NULL); tm = localtime (&timer); pthread_mutex_lock (&date_thread_mutex); today.dd = tm->tm_mday; today.mm = tm->tm_mon + 1; today.yyyy = tm->tm_year + 1900; pthread_mutex_unlock (&date_thread_mutex); } /* Needed to display sunday or monday as the first day of week in calendar. */ void calendar_set_first_day_of_week (enum wday first_day) { switch (first_day) { case SUNDAY: week_begins_on_monday = 0; break; case MONDAY: week_begins_on_monday = 1; break; default: ERROR_MSG (_("ERROR setting first day of week")); week_begins_on_monday = 0; /* NOTREACHED */ } } /* Swap first day of week in calendar. */ void calendar_change_first_day_of_week (void) { week_begins_on_monday = !week_begins_on_monday; } /* Return 1 if week begins on monday, 0 otherwise. */ unsigned calendar_week_begins_on_monday (void) { return (week_begins_on_monday); } /* Fill in the given variable with the current date. */ void calendar_store_current_date (struct date *date) { pthread_mutex_lock (&date_thread_mutex); *date = today; pthread_mutex_unlock (&date_thread_mutex); } /* This is to start at the current date in calendar. */ void calendar_init_slctd_day (void) { calendar_store_current_date (&slctd_day); } /* Return the selected day in calendar */ struct date * calendar_get_slctd_day (void) { return (&slctd_day); } /* Returned value represents the selected day in calendar (in seconds) */ long calendar_get_slctd_day_sec (void) { return (date2sec (slctd_day, 0, 0)); } static int calendar_get_wday (struct date *date) { struct tm t; (void)memset (&t, 0, sizeof (struct tm)); t.tm_mday = date->dd; t.tm_mon = date->mm - 1; t.tm_year = date->yyyy - 1900; (void)mktime (&t); return t.tm_wday; } static int isBissextile (unsigned year) { return (year % 400 == 0 || (year % 4 == 0 && year % 100 != 0)); } static unsigned months_to_days (unsigned month) { return ((month * 3057 - 3007) / 100); } static long years_to_days (unsigned year) { return (year * 365L + year / 4 - year / 100 + year / 400); } static long ymd_to_scalar (unsigned year, unsigned month, unsigned day) { long scalar; scalar = day + months_to_days (month); if (month > 2) scalar -= isBissextile (year) ? 1 : 2; year--; scalar += years_to_days (year); return (scalar); } /* * Used to change date by adding a certain amount of days or weeks. * Returns 0 on success, 1 otherwise. */ static int date_change (struct tm *date, int delta_month, int delta_day) { struct tm t; t = *date; t.tm_mon += delta_month; t.tm_mday += delta_day; if (mktime (&t) == -1) return (1); else { *date = t; return (0); } } /* Draw the monthly view inside calendar panel. */ static void draw_monthly_view (struct window *cwin, struct date *current_day, unsigned sunday_first) { const int OFFY = 2 + (CALHEIGHT - 9) / 2; struct date check_day; int c_day, c_day_1, day_1_sav, numdays, j; unsigned yr, mo; int OFFX, SBAR_WIDTH, ofs_x, ofs_y; int item_this_day = 0; mo = slctd_day.mm; yr = slctd_day.yyyy; /* offset for centering calendar in window */ SBAR_WIDTH = wins_sbar_width (); OFFX = (SBAR_WIDTH - 27) / 2; ofs_y = OFFY; ofs_x = OFFX; /* checking the number of days in february */ numdays = days[mo - 1]; if (2 == mo && isBissextile (yr)) ++numdays; /* * the first calendar day will be monday or sunday, depending on * 'week_begins_on_monday' value */ c_day_1 = (int) ((ymd_to_scalar (yr, mo, 1 + sunday_first) - (long) 1) % 7L); /* Write the current month and year on top of the calendar */ custom_apply_attr (cwin->p, ATTR_HIGHEST); mvwprintw (cwin->p, ofs_y, (SBAR_WIDTH - (strlen (_(monthnames[mo - 1])) + 5)) / 2, "%s %d", _(monthnames[mo - 1]), slctd_day.yyyy); custom_remove_attr (cwin->p, ATTR_HIGHEST); ++ofs_y; /* print the days, with regards to the first day of the week */ custom_apply_attr (cwin->p, ATTR_HIGHEST); for (j = 0; j < WEEKINDAYS; j++) { mvwprintw (cwin->p, ofs_y, ofs_x + 4 * j, "%s", _(daynames[1 + j - sunday_first])); } custom_remove_attr (cwin->p, ATTR_HIGHEST); day_1_sav = (c_day_1 + 1) * 3 + c_day_1 - 7; for (c_day = 1; c_day <= numdays; ++c_day, ++c_day_1, c_day_1 %= 7) { check_day.dd = c_day; check_day.mm = slctd_day.mm; check_day.yyyy = slctd_day.yyyy; /* check if the day contains an event or an appointment */ item_this_day = day_check_if_item (check_day); /* Go to next line, the week is over. */ if (!c_day_1 && 1 != c_day) { ofs_y++; ofs_x = OFFX - day_1_sav - 4 * c_day; } /* This is today, so print it in yellow. */ if (c_day == current_day->dd && current_day->mm == slctd_day.mm && current_day->yyyy == slctd_day.yyyy && current_day->dd != slctd_day.dd) { custom_apply_attr (cwin->p, ATTR_LOWEST); mvwprintw (cwin->p, ofs_y + 1, ofs_x + day_1_sav + 4 * c_day + 1, "%2d", c_day); custom_remove_attr (cwin->p, ATTR_LOWEST); } else if (c_day == slctd_day.dd) { /* This is the selected day, print it according to user's theme. */ custom_apply_attr (cwin->p, ATTR_HIGHEST); mvwprintw (cwin->p, ofs_y + 1, ofs_x + day_1_sav + 4 * c_day + 1, "%2d", c_day); custom_remove_attr (cwin->p, ATTR_HIGHEST); } else if (item_this_day) { custom_apply_attr (cwin->p, ATTR_LOW); mvwprintw (cwin->p, ofs_y + 1, ofs_x + day_1_sav + 4 * c_day + 1, "%2d", c_day); custom_remove_attr (cwin->p, ATTR_LOW); } else /* otherwise, print normal days in black */ mvwprintw (cwin->p, ofs_y + 1, ofs_x + day_1_sav + 4 * c_day + 1, "%2d", c_day); } } static int weeknum (const struct tm *t, int firstweekday) { int wday, wnum; wday = t->tm_wday; if (firstweekday == MONDAY) { if (wday == SUNDAY) wday = 6; else wday--; } wnum = ((t->tm_yday + WEEKINDAYS - wday) / WEEKINDAYS); if (wnum < 0) wnum = 0; return wnum; } /* * Compute the week number according to ISO 8601. */ static int ISO8601weeknum (const struct tm *t) { int wnum, jan1day; wnum = weeknum (t, MONDAY); jan1day = t->tm_wday - (t->tm_yday % WEEKINDAYS); if (jan1day < 0) jan1day += WEEKINDAYS; switch (jan1day) { case MONDAY: break; case TUESDAY: case WEDNESDAY: case THURSDAY: wnum++; break; case FRIDAY: case SATURDAY: case SUNDAY: if (wnum == 0) { /* Get week number of last week of last year. */ struct tm dec31ly; /* 12/31 last year */ dec31ly = *t; dec31ly.tm_year--; dec31ly.tm_mon = 11; dec31ly.tm_mday = 31; dec31ly.tm_wday = (jan1day == SUNDAY) ? 6 : jan1day - 1; dec31ly.tm_yday = 364 + isBissextile (dec31ly.tm_year + 1900); wnum = ISO8601weeknum (&dec31ly); } break; } if (t->tm_mon == 11) { int wday, mday; wday = t->tm_wday; mday = t->tm_mday; if ((wday == MONDAY && (mday >= 29 && mday <= 31)) || (wday == TUESDAY && (mday == 30 || mday == 31)) || (wday == WEDNESDAY && mday == 31)) wnum = 1; } return wnum; } /* Draw the weekly view inside calendar panel. */ static void draw_weekly_view (struct window *cwin, struct date *current_day, unsigned sunday_first) { #define DAYSLICESNO 6 const int WCALWIDTH = 30; const int OFFY = 2 + (CALHEIGHT - 9) / 2; struct tm t; int OFFX, j, c_wday, days_to_remove, weeknum; OFFX = (wins_sbar_width () - WCALWIDTH) / 2 + 1; /* Fill in a tm structure with the first day of the selected week. */ c_wday = calendar_get_wday (&slctd_day); if (sunday_first) days_to_remove = c_wday; else days_to_remove = c_wday == 0 ? WEEKINDAYS - 1 : c_wday - 1; (void)memset (&t, 0, sizeof (struct tm)); t.tm_mday = slctd_day.dd; t.tm_mon = slctd_day.mm - 1; t.tm_year = slctd_day.yyyy - 1900; (void)mktime (&t); (void)date_change (&t, 0, -days_to_remove); /* Print the week number. */ weeknum = ISO8601weeknum (&t); custom_apply_attr (cwin->p, ATTR_HIGHEST); mvwprintw (cwin->p, 2, cwin->w - 9, "(# %02d)", weeknum); custom_remove_attr (cwin->p, ATTR_HIGHEST); /* Now draw calendar view. */ for (j = 0; j < WEEKINDAYS; j++) { struct date date; unsigned attr, item_this_day; int i, slices[DAYSLICESNO]; /* print the day names, with regards to the first day of the week */ custom_apply_attr (cwin->p, ATTR_HIGHEST); mvwprintw (cwin->p, OFFY, OFFX + 4 * j, "%s", _(daynames[1 + j - sunday_first])); custom_remove_attr (cwin->p, ATTR_HIGHEST); /* Check if the day to be printed has an item or not. */ date.dd = t.tm_mday; date.mm = t.tm_mon + 1; date.yyyy = t.tm_year + 1900; item_this_day = day_check_if_item (date); /* Print the day numbers with appropriate decoration. */ if (t.tm_mday == current_day->dd && current_day->mm == slctd_day.mm && current_day->yyyy == slctd_day.yyyy && current_day->dd != slctd_day.dd) attr = ATTR_LOWEST; /* today, but not selected */ else if (t.tm_mday == slctd_day.dd) attr = ATTR_HIGHEST; /* selected day */ else if (item_this_day) attr = ATTR_LOW; else attr = 0; if (attr) custom_apply_attr (cwin->p, attr); mvwprintw (cwin->p, OFFY + 1, OFFX + 1 + 4 * j, "%02d", t.tm_mday); if (attr) custom_remove_attr (cwin->p, attr); /* Draw slices indicating appointment times. */ bzero (slices, DAYSLICESNO * sizeof *slices); if (day_chk_busy_slices (date, DAYSLICESNO, slices)) { for (i = 0; i < DAYSLICESNO; i++) { if (j != WEEKINDAYS - 1 && i != DAYSLICESNO - 1) mvwhline (cwin->p, OFFY + 2 + i, OFFX + 3 + 4 * j, ACS_S9, 2); if (slices[i]) { int highlight; highlight = (t.tm_mday == slctd_day.dd) ? 1 : 0; if (highlight) custom_apply_attr (cwin->p, attr); wattron (cwin->p, A_REVERSE); mvwprintw (cwin->p, OFFY + 2 + i, OFFX + 1 + 4 * j, " "); mvwprintw (cwin->p, OFFY + 2 + i, OFFX + 2 + 4 * j, " "); wattroff (cwin->p, A_REVERSE); if (highlight) custom_remove_attr (cwin->p, attr); } } } /* get next day */ (void)date_change (&t, 0, 1); } /* Draw marks to indicate midday on the sides of the calendar. */ custom_apply_attr (cwin->p, ATTR_HIGHEST); mvwhline (cwin->p, OFFY + 1 + DAYSLICESNO / 2, OFFX, ACS_S9, 1); mvwhline (cwin->p, OFFY + 1 + DAYSLICESNO / 2, OFFX + WCALWIDTH - 3, ACS_S9, 1); custom_remove_attr (cwin->p, ATTR_HIGHEST); #undef DAYSLICESNO } /* Function used to display the calendar panel. */ void calendar_update_panel (struct window *cwin) { struct date current_day; unsigned sunday_first; calendar_store_current_date (¤t_day); erase_window_part (cwin->p, 1, 3, cwin->w - 2, cwin->h - 2); mvwhline (cwin->p, 2, 1, ACS_HLINE, cwin->w - 2); sunday_first = calendar_week_begins_on_monday () ? 0 : 1; draw_calendar[calendar_view] (cwin, ¤t_day, sunday_first); wnoutrefresh (cwin->p); } /* Set the selected day in calendar to current day. */ void calendar_goto_today (void) { struct date today; calendar_store_current_date (&today); slctd_day.dd = today.dd; slctd_day.mm = today.mm; slctd_day.yyyy = today.yyyy; } /* * Ask for a date to jump to, then check the correctness of that date * and jump to it. * If the entered date is empty, automatically jump to the current date. * slctd_day is updated with the newly selected date. */ void calendar_change_day (int datefmt) { #define LDAY 11 char selected_day[LDAY] = ""; char outstr[BUFSIZ]; int dday, dmonth, dyear; int wrong_day = 1; char *mesg_line1 = _("The day you entered is not valid " "(should be between 01/01/1902 and 12/31/2037)"); char *mesg_line2 = _("Press [ENTER] to continue"); char *request_date = "Enter the day to go to [ENTER for today] : %s"; while (wrong_day) { (void)snprintf (outstr, BUFSIZ, request_date, DATEFMT_DESC (datefmt)); status_mesg (_(outstr), ""); if (getstring (win[STA].p, selected_day, LDAY, 0, 1) == GETSTRING_ESC) return; else { if (strlen (selected_day) == 0) { wrong_day = 0; calendar_goto_today (); } else if (strlen (selected_day) != LDAY - 1) { wrong_day = 1; } else if (parse_date (selected_day, datefmt, &dyear, &dmonth, &dday)) { wrong_day = 0; /* go to chosen day */ slctd_day.dd = dday; slctd_day.mm = dmonth; slctd_day.yyyy = dyear; } if (wrong_day) { status_mesg (mesg_line1, mesg_line2); (void)wgetch (win[STA].p); } } } return; } void calendar_move (enum move move) { int ret, days_to_remove, days_to_add; struct tm t; (void)memset (&t, 0, sizeof (struct tm)); t.tm_mday = slctd_day.dd; t.tm_mon = slctd_day.mm - 1; t.tm_year = slctd_day.yyyy - 1900; ret = 1; switch (move) { case UP: if ((slctd_day.dd <= 7) && (slctd_day.mm == 1) && (slctd_day.yyyy == 1902)) return; ret = date_change (&t, 0, -WEEKINDAYS); break; case DOWN: if ((slctd_day.dd > days[slctd_day.mm - 1] - 7) && (slctd_day.mm == 12) && (slctd_day.yyyy == 2037)) return; ret = date_change (&t, 0, WEEKINDAYS); break; case LEFT: if ((slctd_day.dd == 1) && (slctd_day.mm == 1) && (slctd_day.yyyy == 1902)) return; ret = date_change (&t, 0, -1); break; case RIGHT: if ((slctd_day.dd == 31) && (slctd_day.mm == 12) && (slctd_day.yyyy == 2037)) return; ret = date_change (&t, 0, 1); break; case WEEK_START: /* Normalize struct tm to get week day number. */ (void)mktime (&t); if (calendar_week_begins_on_monday ()) days_to_remove = ((t.tm_wday == 0) ? WEEKINDAYS - 1 : t.tm_wday - 1); else days_to_remove = ((t.tm_wday == 0) ? 0 : t.tm_wday); ret = date_change (&t, 0, 0 - days_to_remove); break; case WEEK_END: (void)mktime (&t); if (calendar_week_begins_on_monday ()) days_to_add = ((t.tm_wday == 0) ? 0 : WEEKINDAYS - t.tm_wday); else days_to_add = ((t.tm_wday == 0) ? WEEKINDAYS - 1 : WEEKINDAYS - 1 - t.tm_wday); ret = date_change (&t, 0, days_to_add); break; default: ret = 1; /* NOTREACHED */ } if (ret == 0) { slctd_day.dd = t.tm_mday; slctd_day.mm = t.tm_mon + 1; slctd_day.yyyy = t.tm_year + 1900; } } /* Returns the beginning of current year as a long. */ long calendar_start_of_year (void) { time_t timer; struct tm *tm; timer = time (NULL); tm = localtime (&timer); tm->tm_mon = 0; tm->tm_mday = 1; tm->tm_hour = 0; tm->tm_min = 0; tm->tm_sec = 0; timer = mktime (tm); return (long)timer; } long calendar_end_of_year (void) { time_t timer; struct tm *tm; timer = time (NULL); tm = localtime (&timer); tm->tm_mon = 0; tm->tm_mday = 1; tm->tm_hour = 0; tm->tm_min = 0; tm->tm_sec = 0; tm->tm_year++; timer = mktime (tm); 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; } /* * potm -- * return phase of the moon */ 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 */ } /* * 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 * */ static double pom (time_t tmpt) { struct tm *GMT; double days; int cnt; enum pom pom; pom = NO_POM; 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, so it represents * the phase of the moon for previous day. */ char * calendar_get_pom (time_t date) { char *pom_pict[MOON_PHASES] = { " ", "|) ", "(|)", "(| ", " | " }; enum pom phase = NO_POM; double pom_today, relative_pom, pom_yesterday, pom_tomorrow; const double half = 50.0; pom_yesterday = pom (date); pom_today = pom (date + DAYINSEC); relative_pom = abs (pom_today - half); pom_tomorrow = pom (date + 2 * DAYINSEC); if (pom_today > pom_yesterday && pom_today > pom_tomorrow) phase = FULL_MOON; else if (pom_today < pom_yesterday && pom_today < pom_tomorrow) phase = NEW_MOON; else if (relative_pom < abs (pom_yesterday - half) && relative_pom < abs (pom_tomorrow - half)) phase = (pom_tomorrow > pom_today) ? FIRST_QUARTER : LAST_QUARTER; return (pom_pict[phase]); }