/*
* Calcurse - text-based organizer
*
* Copyright (c) 2004-2013 calcurse Development Team <misc@calcurse.org>
* 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 : misc@calcurse.org
* Calcurse home page : http://calcurse.org
*
*/
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <time.h>
#include <math.h>
#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;
static pthread_t ui_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};
static int monthly_view_cache[MAXDAYSPERMONTH];
static int monthly_view_cache_valid = 0;
static int monthly_view_cache_month = 0;
/* Switch between calendar views (monthly view is selected by default). */
void ui_calendar_view_next(void)
{
ui_calendar_view++;
if (ui_calendar_view == CAL_VIEWS)
ui_calendar_view = 0;
}
void ui_calendar_view_prev(void)
{
if (ui_calendar_view == 0)
ui_calendar_view = CAL_VIEWS;
ui_calendar_view--;
}
void ui_calendar_set_view(int view)
{
ui_calendar_view = (view < 0 || view >= CAL_VIEWS) ? CAL_MONTH_VIEW : view;
}
int ui_calendar_get_view(void)
{
return (int)ui_calendar_view;
}
/* Thread needed to update current date in calendar. */
/* ARGSUSED0 */
static void *ui_calendar_date_thread(void *arg)
{
time_t actual, tomorrow;
for (;;) {
tomorrow = (time_t) (get_today() + DAYINSEC);
while ((actual = time(NULL)) < tomorrow)
sleep(tomorrow - actual);
ui_calendar_set_current_date();
ui_calendar_update_panel(&win[CAL]);
}
return NULL;
}
/* Launch the calendar date thread. */
void ui_calendar_start_date_thread(void)
{
pthread_create(&ui_calendar_t_date, NULL, ui_calendar_date_thread, NULL);
}
/* Stop the calendar date thread. */
void ui_calendar_stop_date_thread(void)
{
if (ui_calendar_t_date) {
pthread_cancel(ui_calendar_t_date);
pthread_join(ui_calendar_t_date, NULL);
}
}
/* Set static variable today to current date */
void ui_calendar_set_current_date(void)
{
time_t timer;
struct tm tm;
timer = time(NULL);
localtime_r(&timer, &tm);
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 ui_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 ui_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 ui_calendar_week_begins_on_monday(void)
{
return week_begins_on_monday;
}
/* Fill in the given variable with the current date. */
void ui_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 ui_calendar_init_slctd_day(void)
{
ui_calendar_store_current_date(&slctd_day);
}
/* Return the selected day in calendar */
struct date *ui_calendar_get_slctd_day(void)
{
return &slctd_day;
}
/* Returned value represents the selected day in calendar (in seconds) */
long ui_calendar_get_slctd_day_sec(void)
{
return date2sec(slctd_day, 0, 0);
}
static int ui_calendar_get_wday(struct date *date)
{
struct tm t;
memset(&t, 0, sizeof(struct tm));
t.tm_mday = date->dd;
t.tm_mon = date->mm - 1;
t.tm_year = date->yyyy - 1900;
mktime(&t);
return t.tm_wday;
}
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 -= ISLEAP(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;
}
}
void ui_calendar_monthly_view_cache_set_invalid(void)
{
monthly_view_cache_valid = 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 = CALHEIGHT / 2 - (conf.compact_panels ? 3 : 1);
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 && ISLEAP(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 */
WINS_CALENDAR_LOCK;
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++) {
mvwaddstr(cwin->p, ofs_y, ofs_x + 4 * j, _(daynames[1 + j - sunday_first]));
}
custom_remove_attr(cwin->p, ATTR_HIGHEST);
WINS_CALENDAR_UNLOCK;
day_1_sav = (c_day_1 + 1) * 3 + c_day_1 - 7;
/* invalidate cache if a new month is selected */
if (yr * YEARINMONTHS + mo != monthly_view_cache_month) {
monthly_view_cache_month = yr * YEARINMONTHS + mo;
monthly_view_cache_valid = 0;
}
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 */
if (monthly_view_cache_valid) {
item_this_day = monthly_view_cache[c_day - 1];
} else {
item_this_day = monthly_view_cache[c_day - 1] =
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;
}
WINS_CALENDAR_LOCK;
if (c_day == current_day->dd
&& current_day->mm == slctd_day.mm
&& current_day->yyyy == slctd_day.yyyy
&& current_day->dd != slctd_day.dd) {
/* This is today, so print it in yellow. */
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);
}
WINS_CALENDAR_UNLOCK;
}
monthly_view_cache_valid = 1;
}
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 + ISLEAP(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 = CALHEIGHT / 2 - (conf.compact_panels ? 3 : 1);
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 = ui_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;
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;
mktime(&t);
date_change(&t, 0, -days_to_remove);
/* Print the week number. */
weeknum = ISO8601weeknum(&t);
WINS_CALENDAR_LOCK;
custom_apply_attr(cwin->p, ATTR_HIGHEST);
mvwprintw(cwin->p, conf.compact_panels ? 0 : 2, cwin->w - 9, "(# %02d)",
weeknum);
custom_remove_attr(cwin->p, ATTR_HIGHEST);
WINS_CALENDAR_UNLOCK;
/* 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);
mvwaddstr(cwin->p, OFFY, OFFX + 4 * j, _(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;
WINS_CALENDAR_LOCK;
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);
WINS_CALENDAR_UNLOCK;
/* Draw slices indicating appointment times. */
memset(slices, 0, DAYSLICESNO * sizeof *slices);
if (day_chk_busy_slices(date, DAYSLICESNO, slices)) {
for (i = 0; i < DAYSLICESNO; i++) {
if (j != WEEKINDAYS - 1 && i != DAYSLICESNO - 1) {
WINS_CALENDAR_LOCK;
mvwhline(cwin->p, OFFY + 2 + i, OFFX + 3 + 4 * j, ACS_S9, 2);
WINS_CALENDAR_UNLOCK;
}
if (slices[i]) {
int highlight;
highlight = (t.tm_mday == slctd_day.dd) ? 1 : 0;
WINS_CALENDAR_LOCK;
if (highlight)
custom_apply_attr(cwin->p, attr);
wattron(cwin->p, A_REVERSE);
mvwaddstr(cwin->p, OFFY + 2 + i, OFFX + 1 + 4 * j, " ");
mvwaddstr(cwin->p, OFFY + 2 + i, OFFX + 2 + 4 * j, " ");
wattroff(cwin->p, A_REVERSE);
if (highlight)
custom_remove_attr(cwin->p, attr);
WINS_CALENDAR_UNLOCK;
}
}
}
/* get next day */
date_change(&t, 0, 1);
}
/* Draw marks to indicate midday on the sides of the calendar. */
WINS_CALENDAR_LOCK;
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);
WINS_CALENDAR_UNLOCK;
#undef DAYSLICESNO
}
/* Function used to display the calendar panel. */
void ui_calendar_update_panel(struct window *cwin)
{
struct date current_day;
unsigned sunday_first;
ui_calendar_store_current_date(¤t_day);
WINS_CALENDAR_LOCK;
erase_window_part(cwin->p, 1, conf.compact_panels ? 1 : 3, cwin->w - 2,
cwin->h - 2);
if (!conf.compact_panels)
mvwhline(cwin->p, 2, 1, ACS_HLINE, cwin->w - 2);
WINS_CALENDAR_UNLOCK;
sunday_first = ui_calendar_week_begins_on_monday()? 0 : 1;
draw_calendar[ui_calendar_view] (cwin, ¤t_day, sunday_first);
wnoutrefresh(cwin->p);
}
/* Set the selected day in calendar to current day. */
void ui_calendar_goto_today(void)
{
struct date today;
ui_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 ui_calendar_change_day(int datefmt)
{
#define LDAY 11
char selected_day[LDAY] = "";
char outstr[BUFSIZ];
int dday, dmonth, dyear;
int wrong_day = 1;
const char *mesg_line1 =
_("The day you entered is not valid "
"(should be between 01/01/1902 and 12/31/2037)");
const char *mesg_line2 = _("Press [ENTER] to continue");
const char *request_date = _("Enter the day to go to [ENTER for today] : %s");
while (wrong_day) {
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;
ui_calendar_goto_today();
} else if (parse_date(selected_day, datefmt, &dyear, &dmonth, &dday,
ui_calendar_get_slctd_day())) {
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);
wgetch(win[KEY].p);
}
}
}
return;
}
void ui_calendar_move(enum move move, int count)
{
int ret, days_to_remove, days_to_add;
struct tm t;
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;
switch (move) {
case DAY_PREV:
ret = date_change(&t, 0, -count);
break;
case DAY_NEXT:
ret = date_change(&t, 0, count);
break;
case WEEK_PREV:
ret = date_change(&t, 0, -count * WEEKINDAYS);
break;
case WEEK_NEXT:
ret = date_change(&t, 0, count * WEEKINDAYS);
break;
case MONTH_PREV:
ret = date_change(&t, -count, 0);
break;
case MONTH_NEXT:
ret = date_change(&t, count, 0);
break;
case YEAR_PREV:
ret = date_change(&t, -count * YEARINMONTHS, 0);
break;
case YEAR_NEXT:
ret = date_change(&t, count * YEARINMONTHS, 0);
break;
case WEEK_START:
/* Normalize struct tm to get week day number. */
mktime(&t);
if (ui_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);
days_to_remove += (count - 1) * WEEKINDAYS;
ret = date_change(&t, 0, -days_to_remove);
break;
case WEEK_END:
mktime(&t);
if (ui_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);
days_to_add += (count - 1) * WEEKINDAYS;
ret = date_change(&t, 0, days_to_add);
break;
default:
ret = 1;
/* NOTREACHED */
}
if (ret == 0) {
if (t.tm_year < 2) {
t.tm_mday = 1;
t.tm_mon = 0;
t.tm_year = 2;
} else if (t.tm_year > 137) {
t.tm_mday = 31;
t.tm_mon = 11;
t.tm_year = 137;
}
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 ui_calendar_start_of_year(void)
{
time_t timer;
struct tm tm;
timer = time(NULL);
localtime_r(&timer, &tm);
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 ui_calendar_end_of_year(void)
{
time_t timer;
struct tm tm;
timer = time(NULL);
localtime_r(&timer, &tm);
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;
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.
*/
const char *ui_calendar_get_pom(time_t date)
{
const 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];
}
