gnucash/libgnucash/engine/Recurrence.c
2021-01-22 10:19:54 +01:00

898 lines
27 KiB
C

/* Copyright (C) 2005, Chris Shoemaker <c.shoemaker@cox.net>
*
* This program 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 program 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, contact:
*
* Free Software Foundation Voice: +1-617-542-5942
* 51 Franklin Street, Fifth Floor Fax: +1-617-542-2652
* Boston, MA 02110-1301, USA gnu@gnu.org
*/
#include <config.h>
#include <time.h>
#include <glib.h>
#include <glib/gi18n.h>
#include <string.h>
#include <stdint.h>
#include "Recurrence.h"
#include "gnc-date.h"
#include "qof.h"
#include "gnc-engine.h"
#include "gnc-date.h"
#include "Account.h"
#include <stdint.h>
#include <stdint.h>
#include <stdint.h>
#define LOG_MOD "gnc.engine.recurrence"
static QofLogModule log_module = LOG_MOD;
#undef G_LOG_DOMAIN
#define G_LOG_DOMAIN LOG_MOD
static GDate invalid_gdate;
/* Do not intl. These are used for xml storage. */
static gchar *period_type_strings[NUM_PERIOD_TYPES] =
{
"once", "day", "week", "month", "end of month",
"nth weekday", "last weekday", "year",
};
static gchar *weekend_adj_strings[NUM_WEEKEND_ADJS] =
{
"none", "back", "forward",
};
#define VALID_PERIOD_TYPE(pt) ((0 <= (pt)) && ((pt) < NUM_PERIOD_TYPES))
#define VALID_WEEKEND_ADJ(wadj) ((0 <= (wadj)) && ((wadj) < NUM_WEEKEND_ADJS))
PeriodType
recurrenceGetPeriodType(const Recurrence *r)
{
return r ? r->ptype : PERIOD_INVALID;
}
guint
recurrenceGetMultiplier(const Recurrence *r)
{
return r ? r->mult : 0;
}
GDate
recurrenceGetDate(const Recurrence *r)
{
return r ? r->start : invalid_gdate;
}
time64
recurrenceGetTime(const Recurrence *r)
{
return r ? gdate_to_time64(r->start) : INT64_MAX;
}
WeekendAdjust
recurrenceGetWeekendAdjust(const Recurrence *r)
{
return r ? r->wadj : WEEKEND_ADJ_INVALID;
}
void
recurrenceSet(Recurrence *r, guint16 mult, PeriodType pt, const GDate *_start, WeekendAdjust wadj)
{
r->ptype = VALID_PERIOD_TYPE(pt) ? pt : PERIOD_MONTH;
r->mult = (pt == PERIOD_ONCE) ? 0 : (mult > 0 ? mult : 1);
if (_start && g_date_valid(_start))
{
r->start = *_start;
}
else
{
gnc_gdate_set_today (&r->start);
}
/* Some of the unusual period types also specify phase. For those
types, we ensure that the start date agrees with that phase. */
switch (r->ptype)
{
case PERIOD_END_OF_MONTH:
g_date_set_day(&r->start, g_date_get_days_in_month
(g_date_get_month(&r->start),
g_date_get_year(&r->start)));
break;
case PERIOD_LAST_WEEKDAY:
{
GDateDay dim;
dim = g_date_get_days_in_month(g_date_get_month(&r->start),
g_date_get_year(&r->start));
while (dim - g_date_get_day(&r->start) >= 7)
g_date_add_days(&r->start, 7);
}
break;
case PERIOD_NTH_WEEKDAY:
if ((g_date_get_day(&r->start) - 1) / 7 == 4) /* Fifth week */
r->ptype = PERIOD_LAST_WEEKDAY;
break;
default:
break;
}
switch (r->ptype)
{
case PERIOD_MONTH:
case PERIOD_END_OF_MONTH:
case PERIOD_YEAR:
r->wadj = wadj;
break;
default:
r->wadj = WEEKEND_ADJ_NONE;
break;
}
}
/* nth_weekday_compare() is a helper function for the
PERIOD_{NTH,LAST}_WEEKDAY case. It returns the offset, in days,
from 'next' to the nth weekday specified by the 'start' date (and
the period type), in the same month as 'next'. A negative offset
means earlier than 'next'; a zero offset means 'next' *is* the nth
weekday in that month; a positive offset means later than
'next'. */
static gint
nth_weekday_compare(const GDate *start, const GDate *next, PeriodType pt)
{
GDateDay sd, nd;
gint matchday, dim, week;
nd = g_date_get_day(next);
sd = g_date_get_day(start);
week = sd / 7 > 3 ? 3 : sd / 7;
if (week > 0 && sd % 7 == 0 && sd != 28)
--week;
/* matchday has a week part, capped at 3 weeks, and a day part,
capped at 7 days, so max(matchday) == 3*7 + 7 == 28. */
matchday = 7 * week + //((sd - 1) / 7 == 4 ? 3 : (sd - 1) / 7) +
(nd - g_date_get_weekday(next) + g_date_get_weekday(start) + 7) % 7;
/* That " + 7" is to avoid negative modulo in case nd < 6. */
dim = g_date_get_days_in_month(
g_date_get_month(next), g_date_get_year(next));
if ((dim - matchday) >= 7 && pt == PERIOD_LAST_WEEKDAY)
matchday += 7; /* Go to the fifth week, if needed */
if (pt == PERIOD_NTH_WEEKDAY && (matchday % 7 == 0))
matchday += 7;
return matchday - nd; /* Offset from 'next' to matchday */
}
static void adjust_for_weekend(PeriodType pt, WeekendAdjust wadj, GDate *date)
{
if (pt == PERIOD_YEAR || pt == PERIOD_MONTH || pt == PERIOD_END_OF_MONTH)
{
if (g_date_get_weekday(date) == G_DATE_SATURDAY || g_date_get_weekday(date) == G_DATE_SUNDAY)
{
switch (wadj)
{
case WEEKEND_ADJ_BACK:
g_date_subtract_days(date, g_date_get_weekday(date) == G_DATE_SATURDAY ? 1 : 2);
break;
case WEEKEND_ADJ_FORWARD:
g_date_add_days(date, g_date_get_weekday(date) == G_DATE_SATURDAY ? 2 : 1);
break;
case WEEKEND_ADJ_NONE:
default:
break;
}
}
}
}
/* This is the only real algorithm related to recurrences. It goes:
Step 1) Go forward one period from the reference date.
Step 2) Back up to align to the phase of the start date.
*/
void
recurrenceNextInstance(const Recurrence *r, const GDate *ref, GDate *next)
{
PeriodType pt;
const GDate *start;
GDate adjusted_start;
guint mult;
WeekendAdjust wadj;
g_return_if_fail(r);
g_return_if_fail(ref);
g_return_if_fail(g_date_valid(&r->start));
g_return_if_fail(g_date_valid(ref));
start = &r->start;
mult = r->mult;
pt = r->ptype;
wadj = r->wadj;
/* If the ref date comes before the start date then the next
occurrence is always the start date, and we're done. */
// However, it's possible for the start date to fall on an exception (a weekend), in that case, it needs to be corrected.
adjusted_start = *start;
adjust_for_weekend(pt,wadj,&adjusted_start);
if (g_date_compare(ref, &adjusted_start) < 0)
{
g_date_set_julian(next, g_date_get_julian(&adjusted_start));
return;
}
g_date_set_julian(next, g_date_get_julian(ref)); /* start at refDate */
/* Step 1: move FORWARD one period, passing exactly one occurrence. */
switch (pt)
{
case PERIOD_YEAR:
mult *= 12;
/* fall through */
case PERIOD_MONTH:
case PERIOD_NTH_WEEKDAY:
case PERIOD_LAST_WEEKDAY:
case PERIOD_END_OF_MONTH:
/* Takes care of short months. */
if (r->wadj == WEEKEND_ADJ_BACK &&
(pt == PERIOD_YEAR || pt == PERIOD_MONTH || pt == PERIOD_END_OF_MONTH) &&
(g_date_get_weekday(next) == G_DATE_SATURDAY || g_date_get_weekday(next) == G_DATE_SUNDAY))
{
/* Allows the following Friday-based calculations to proceed if 'next'
is between Friday and the target day. */
g_date_subtract_days(next, g_date_get_weekday(next) == G_DATE_SATURDAY ? 1 : 2);
}
if (r->wadj == WEEKEND_ADJ_BACK &&
(pt == PERIOD_YEAR || pt == PERIOD_MONTH || pt == PERIOD_END_OF_MONTH) &&
g_date_get_weekday(next) == G_DATE_FRIDAY)
{
GDate tmp_sat;
GDate tmp_sun;
g_date_set_julian(&tmp_sat, g_date_get_julian(next));
g_date_set_julian(&tmp_sun, g_date_get_julian(next));
g_date_add_days(&tmp_sat, 1);
g_date_add_days(&tmp_sun, 2);
if (pt == PERIOD_END_OF_MONTH)
{
if (g_date_is_last_of_month(next) ||
g_date_is_last_of_month(&tmp_sat) ||
g_date_is_last_of_month(&tmp_sun))
g_date_add_months(next, mult);
else
/* one fewer month fwd because of the occurrence in this month */
g_date_add_months(next, mult - 1);
}
else
{
if (g_date_get_day(&tmp_sat) == g_date_get_day(start))
{
g_date_add_days(next, 1);
g_date_add_months(next, mult);
}
else if (g_date_get_day(&tmp_sun) == g_date_get_day(start))
{
g_date_add_days(next, 2);
g_date_add_months(next, mult);
}
else if (g_date_get_day(next) >= g_date_get_day(start))
{
g_date_add_months(next, mult);
}
else if (g_date_is_last_of_month(next))
{
g_date_add_months(next, mult);
}
else if (g_date_is_last_of_month(&tmp_sat))
{
g_date_add_days(next, 1);
g_date_add_months(next, mult);
}
else if (g_date_is_last_of_month(&tmp_sun))
{
g_date_add_days(next, 2);
g_date_add_months(next, mult);
}
else
{
/* one fewer month fwd because of the occurrence in this month */
g_date_add_months(next, mult - 1);
}
}
}
else if ( g_date_is_last_of_month(next) ||
((pt == PERIOD_MONTH || pt == PERIOD_YEAR) &&
g_date_get_day(next) >= g_date_get_day(start)) ||
((pt == PERIOD_NTH_WEEKDAY || pt == PERIOD_LAST_WEEKDAY) &&
nth_weekday_compare(start, next, pt) <= 0) )
g_date_add_months(next, mult);
else
/* one fewer month fwd because of the occurrence in this month */
g_date_add_months(next, mult - 1);
break;
case PERIOD_WEEK:
mult *= 7;
/* fall through */
case PERIOD_DAY:
g_date_add_days(next, mult);
break;
case PERIOD_ONCE:
g_date_clear(next, 1); /* We already caught the case where ref is */
return; /* earlier than start, so this is invalid. */
default:
PERR("Invalid period type");
break;
}
/* Step 2: Back up to align to the base phase. To ensure forward
progress, we never subtract as much as we added (x % mult < mult). */
switch (pt)
{
case PERIOD_YEAR:
case PERIOD_MONTH:
case PERIOD_NTH_WEEKDAY:
case PERIOD_LAST_WEEKDAY:
case PERIOD_END_OF_MONTH:
{
guint dim, n_months;
n_months = 12 * (g_date_get_year(next) - g_date_get_year(start)) +
(g_date_get_month(next) - g_date_get_month(start));
g_date_subtract_months(next, n_months % mult);
/* Ok, now we're in the right month, so we just have to align
the day in one of the three possible ways. */
dim = g_date_get_days_in_month(g_date_get_month(next),
g_date_get_year(next));
if (pt == PERIOD_LAST_WEEKDAY || pt == PERIOD_NTH_WEEKDAY)
{
gint wdresult = nth_weekday_compare(start, next, pt);
if (wdresult < 0)
{
wdresult = -wdresult;
g_date_subtract_days(next, wdresult);
}
else
g_date_add_days(next, wdresult);
}
else if (pt == PERIOD_END_OF_MONTH || g_date_get_day(start) >= dim)
g_date_set_day(next, dim); /* last day in the month */
else
g_date_set_day(next, g_date_get_day(start)); /*same day as start*/
/* Adjust for dates on the weekend. */
adjust_for_weekend(pt,wadj,next);
}
break;
case PERIOD_WEEK:
case PERIOD_DAY:
g_date_subtract_days(next, g_date_days_between(start, next) % mult);
break;
default:
PERR("Invalid period type");
break;
}
}
/* Zero-based index */
void
recurrenceNthInstance(const Recurrence *r, guint n, GDate *date)
{
GDate ref;
guint i;
for (*date = ref = r->start, i = 0; i < n; i++)
{
recurrenceNextInstance(r, &ref, date);
ref = *date;
}
}
time64
recurrenceGetPeriodTime(const Recurrence *r, guint period_num, gboolean end)
{
GDate date;
time64 time;
recurrenceNthInstance(r, period_num + (end ? 1 : 0), &date);
if (end)
{
g_date_subtract_days(&date, 1);
time = gnc_dmy2time64_end (g_date_get_day(&date),
g_date_get_month(&date),
g_date_get_year (&date));
}
else
{
time = gnc_dmy2time64 (g_date_get_day(&date),
g_date_get_month(&date),
g_date_get_year (&date));
}
return time;
}
gnc_numeric
recurrenceGetAccountPeriodValue(const Recurrence *r, Account *acc, guint n)
{
time64 t1, t2;
// FIXME: maybe zero is not best error return val.
g_return_val_if_fail(r && acc, gnc_numeric_zero());
t1 = recurrenceGetPeriodTime(r, n, FALSE);
t2 = recurrenceGetPeriodTime(r, n, TRUE);
return xaccAccountGetNoclosingBalanceChangeForPeriod (acc, t1, t2, TRUE);
}
void
recurrenceListNextInstance(const GList *rlist, const GDate *ref, GDate *next)
{
const GList *iter;
GDate nextSingle; /* The next date for an individual recurrence */
g_date_clear(next, 1);
// empty rlist = no recurrence
if (rlist == NULL)
{
return;
}
g_return_if_fail(ref && next && g_date_valid(ref));
for (iter = rlist; iter; iter = iter->next)
{
const Recurrence *r = iter->data;
recurrenceNextInstance(r, ref, &nextSingle);
if (!g_date_valid(&nextSingle)) continue;
if (g_date_valid(next))
g_date_order(next, &nextSingle); /* swaps dates if needed */
else
*next = nextSingle; /* first date is always earliest so far */
}
}
/* Caller owns the returned memory */
gchar *
recurrenceToString(const Recurrence *r)
{
gchar *tmpDate;
gchar *tmpPeriod, *ret;
g_return_val_if_fail(g_date_valid(&r->start), NULL);
tmpDate = g_new0(gchar, MAX_DATE_LENGTH + 1);
g_date_strftime(tmpDate, MAX_DATE_LENGTH, "%x", &r->start);
if (r->ptype == PERIOD_ONCE)
{
ret = g_strdup_printf("once on %s", tmpDate);
goto done;
}
tmpPeriod = period_type_strings[r->ptype];
if (r->mult > 1)
ret = g_strdup_printf("Every %d %ss beginning %s",
r->mult, tmpPeriod, tmpDate);
else
ret = g_strdup_printf("Every %s beginning %s",
tmpPeriod, tmpDate);
done:
g_free(tmpDate);
return ret;
}
/* caller owns the returned memory */
gchar *
recurrenceListToString(const GList *r)
{
const GList *iter;
GString *str;
gchar *s;
str = g_string_new("");
if (r == NULL)
{
g_string_append(str, _("None"));
}
else
{
for (iter = r; iter; iter = iter->next)
{
if (iter != r)
{
/* Translators: " + " is an separator in a list of string-representations of recurrence frequencies */
g_string_append(str, _(" + "));
}
s = recurrenceToString((Recurrence *)iter->data);
g_string_append(str, s);
g_free(s);
}
}
return g_string_free(str, FALSE);
}
gchar *
recurrencePeriodTypeToString(PeriodType pt)
{
return VALID_PERIOD_TYPE(pt) ? g_strdup(period_type_strings[pt]) : NULL;
}
PeriodType
recurrencePeriodTypeFromString(const gchar *str)
{
int i;
for (i = 0; i < NUM_PERIOD_TYPES; i++)
if (g_strcmp0(period_type_strings[i], str) == 0)
return i;
return -1;
}
gchar *
recurrenceWeekendAdjustToString(WeekendAdjust wadj)
{
return VALID_WEEKEND_ADJ(wadj) ? g_strdup(weekend_adj_strings[wadj]) : NULL;
}
WeekendAdjust
recurrenceWeekendAdjustFromString(const gchar *str)
{
int i;
for (i = 0; i < NUM_WEEKEND_ADJS; i++)
if (g_strcmp0(weekend_adj_strings[i], str) == 0)
return i;
return -1;
}
gboolean
recurrenceListIsSemiMonthly(GList *recurrences)
{
if (g_list_length(recurrences) != 2)
return FALSE;
// should be a "semi-monthly":
{
Recurrence *first = (Recurrence*)g_list_nth_data(recurrences, 0);
Recurrence *second = (Recurrence*)g_list_nth_data(recurrences, 1);
PeriodType first_period, second_period;
first_period = recurrenceGetPeriodType(first);
second_period = recurrenceGetPeriodType(second);
if (!((first_period == PERIOD_MONTH
|| first_period == PERIOD_END_OF_MONTH
|| first_period == PERIOD_LAST_WEEKDAY)
&& (second_period == PERIOD_MONTH
|| second_period == PERIOD_END_OF_MONTH
|| second_period == PERIOD_LAST_WEEKDAY)))
{
/*g_error("unknown 2-recurrence composite with period_types first [%d] second [%d]",
first_period, second_periodD);*/
return FALSE;
}
}
return TRUE;
}
gboolean
recurrenceListIsWeeklyMultiple(const GList *recurrences)
{
const GList *r_iter;
for (r_iter = recurrences; r_iter != NULL; r_iter = r_iter->next)
{
Recurrence *r = (Recurrence*)r_iter->data;
if (recurrenceGetPeriodType(r) != PERIOD_WEEK)
{
return FALSE;
}
}
return TRUE;
}
static void
_weekly_list_to_compact_string(GList *rs, GString *buf)
{
int dow_idx;
char dow_present_bits = 0;
int multiplier = -1;
for (; rs != NULL; rs = rs->next)
{
Recurrence *r = (Recurrence*)rs->data;
GDate date = recurrenceGetDate(r);
GDateWeekday dow = g_date_get_weekday(&date);
if (dow == G_DATE_BAD_WEEKDAY)
{
g_critical("bad weekday pretty-printing recurrence");
continue;
}
dow_present_bits |= (1 << (dow % 7));
// there's not necessarily a single multiplier, but for all intents
// and purposes this will be fine.
multiplier = recurrenceGetMultiplier(r);
}
g_string_printf(buf, "%s", _("Weekly"));
if (multiplier > 1)
{
/* Translators: %u is the recurrence multiplier, i.e. this
event should occur every %u'th week. */
g_string_append_printf(buf, _(" (x%u)"), multiplier);
}
g_string_append_printf(buf, ": ");
// @@fixme: this is only Sunday-started weeks. :/
for (dow_idx = 0; dow_idx < 7; dow_idx++)
{
if ((dow_present_bits & (1 << dow_idx)) != 0)
{
gchar dbuf[10];
gnc_dow_abbrev(dbuf, 10, dow_idx);
g_string_append_unichar(buf, g_utf8_get_char(dbuf));
}
else
{
g_string_append_printf(buf, "-");
}
}
}
/* A constant is needed for the array size */
#define abbrev_day_name_bufsize 10
static void
_monthly_append_when(Recurrence *r, GString *buf)
{
GDate date = recurrenceGetDate(r);
if (recurrenceGetPeriodType(r) == PERIOD_LAST_WEEKDAY)
{
gchar day_name_buf[abbrev_day_name_bufsize];
gnc_dow_abbrev(day_name_buf, abbrev_day_name_bufsize, g_date_get_weekday(&date) % 7);
/* Translators: %s is an already-localized form of the day of the week. */
g_string_append_printf(buf, _("last %s"), day_name_buf);
}
else if (recurrenceGetPeriodType(r) == PERIOD_NTH_WEEKDAY)
{
int week = 0;
int day_of_month_index = 0;
const char *numerals[] = {N_("1st"), N_("2nd"), N_("3rd"), N_("4th")};
gchar day_name_buf[abbrev_day_name_bufsize];
gnc_dow_abbrev(day_name_buf, abbrev_day_name_bufsize, g_date_get_weekday(&date) % 7);
day_of_month_index = g_date_get_day(&date) - 1;
week = day_of_month_index / 7 > 3 ? 3 : day_of_month_index / 7;
/* Translators: %s is the string 1st, 2nd, 3rd and so on, and
%s is an already-localized form of the day of the week. */
g_string_append_printf(buf, _("%s %s"), _(numerals[week]), day_name_buf);
}
else
{
/* Translators: %u is the day of month */
g_string_append_printf(buf, "%u", g_date_get_day(&date));
}
}
gchar*
recurrenceListToCompactString(GList *rs)
{
GString *buf = g_string_sized_new(16);
if (g_list_length(rs) == 0)
{
g_string_printf(buf, "%s", _("None"));
goto rtn;
}
if (g_list_length(rs) > 1)
{
if (recurrenceListIsWeeklyMultiple(rs))
{
_weekly_list_to_compact_string(rs, buf);
}
else if (recurrenceListIsSemiMonthly(rs))
{
Recurrence *first, *second;
first = (Recurrence*)g_list_nth_data(rs, 0);
second = (Recurrence*)g_list_nth_data(rs, 1);
if (recurrenceGetMultiplier(first) != recurrenceGetMultiplier(second))
{
g_warning("lying about non-equal semi-monthly recurrence multiplier: %d vs. %d",
recurrenceGetMultiplier(first), recurrenceGetMultiplier(second));
}
g_string_printf(buf, "%s", _("Semi-monthly"));
g_string_append_printf(buf, " ");
if (recurrenceGetMultiplier(first) > 1)
{
/* Translators: %u is the recurrence multiplier number */
g_string_append_printf(buf, _(" (x%u)"), recurrenceGetMultiplier(first));
}
g_string_append_printf(buf, ": ");
_monthly_append_when(first, buf);
g_string_append_printf(buf, ", ");
_monthly_append_when(second, buf);
}
else
{
/* Translators: %d is the number of Recurrences in the list. */
g_string_printf(buf, _("Unknown, %d-size list."), g_list_length(rs));
}
}
else
{
Recurrence *r = (Recurrence*)g_list_nth_data(rs, 0);
guint multiplier = recurrenceGetMultiplier(r);
switch (recurrenceGetPeriodType(r))
{
case PERIOD_ONCE:
{
g_string_printf(buf, "%s", _("Once"));
}
break;
case PERIOD_DAY:
{
g_string_printf(buf, "%s", _("Daily"));
if (multiplier > 1)
{
/* Translators: %u is the recurrence multiplier. */
g_string_append_printf(buf, _(" (x%u)"), multiplier);
}
}
break;
case PERIOD_WEEK:
{
_weekly_list_to_compact_string(rs, buf);
}
break;
case PERIOD_MONTH:
case PERIOD_END_OF_MONTH:
case PERIOD_LAST_WEEKDAY:
{
g_string_printf(buf, "%s", _("Monthly"));
if (multiplier > 1)
{
/* Translators: %u is the recurrence multiplier. */
g_string_append_printf(buf, _(" (x%u)"), multiplier);
}
g_string_append_printf(buf, ": ");
_monthly_append_when(r, buf);
}
break;
case PERIOD_NTH_WEEKDAY:
{
//g_warning("nth weekday not handled");
//g_string_printf(buf, "@fixme: nth weekday not handled");
g_string_printf(buf, "%s", _("Monthly"));
if (multiplier > 1)
{
/* Translators: %u is the recurrence multiplier. */
g_string_append_printf(buf, _(" (x%u)"), multiplier);
}
g_string_append_printf(buf, ": ");
_monthly_append_when(r, buf);
}
break;
case PERIOD_YEAR:
{
g_string_printf(buf, "%s", _("Yearly"));
if (multiplier > 1)
{
/* Translators: %u is the recurrence multiplier. */
g_string_append_printf(buf, _(" (x%u)"), multiplier);
}
}
break;
default:
g_error("unknown Recurrence period %d", recurrenceGetPeriodType(r));
break;
}
}
rtn:
return g_string_free(buf, FALSE);
}
/**
* The ordering, in increasing degrees of frequent-ness:
*
* day < week < {nth-weekday < month < end-month, last_weekday} < year < once
*
* all the monthly types are basically together, but are broken down
* internally cause they have to be ordered somehow.
**/
static int cmp_order_indexes[] =
{
6, // PERIOD_ONCE
1, // PERIOD_DAY
2, // PERIOD_WEEK
// 3, // "semi-monthly" ... Note that this isn't presently used, just the
// // way the code worked out. :(
4, // PERIOD_MONTH
4, // PERIOD_END_OF_MONTH
4, // PERIOD_NTH_WEEKDAY
4, // PERIOD_LAST_WEEKDAY
5, // PERIOD_YEAR
};
static int cmp_monthly_order_indexes[] =
{
-1, // PERIOD_ONCE
-1, // PERIOD_DAY
-1, // PERIOD_WEEK
2, // PERIOD_MONTH
3, // PERIOD_END_OF_MONTH
1, // PERIOD_NTH_WEEKDAY
4, // PERIOD_LAST_WEEKDAY
-1, // PERIOD_YEAR
};
int
recurrenceCmp(Recurrence *a, Recurrence *b)
{
PeriodType period_a, period_b;
int a_order_index, b_order_index;
int a_mult, b_mult;
g_return_val_if_fail(a != NULL && b != NULL, 0);
g_return_val_if_fail(a != NULL, 1);
g_return_val_if_fail(b != NULL, -1);
period_a = recurrenceGetPeriodType(a);
period_b = recurrenceGetPeriodType(b);
a_order_index = cmp_order_indexes[period_a];
b_order_index = cmp_order_indexes[period_b];
if (a_order_index != b_order_index)
{
return a_order_index - b_order_index;
}
else if (a_order_index == cmp_order_indexes[PERIOD_MONTH])
{
// re-order intra-month options:
a_order_index = cmp_monthly_order_indexes[period_a];
b_order_index = cmp_monthly_order_indexes[period_b];
g_assert(a_order_index != -1 && b_order_index != -1);
if (a_order_index != b_order_index)
return a_order_index - b_order_index;
}
/* else { the basic periods are equal; compare the multipliers } */
a_mult = recurrenceGetMultiplier(a);
b_mult = recurrenceGetMultiplier(b);
return a_mult - b_mult;
}
int
recurrenceListCmp(GList *a, GList *b)
{
Recurrence *most_freq_a, *most_freq_b;
g_return_val_if_fail(g_list_length(a) != 0 && g_list_length(b) != 0, 0);
g_return_val_if_fail(g_list_length(a) != 0, -1);
g_return_val_if_fail(g_list_length(b) != 0, 1);
most_freq_a = (Recurrence*)g_list_nth_data(g_list_sort(a, (GCompareFunc)recurrenceCmp), 0);
most_freq_b = (Recurrence*)g_list_nth_data(g_list_sort(b, (GCompareFunc)recurrenceCmp), 0);
return recurrenceCmp(most_freq_a, most_freq_b);
}
void
recurrenceListFree(GList **recurrences)
{
g_list_foreach(*recurrences, (GFunc)g_free, NULL);
g_list_free(*recurrences);
*recurrences = NULL;
}