/* GLIB - Library of useful routines for C programming

 * Copyright (C) 1995-1997  Peter Mattis, Spencer Kimball and Josh MacDonald

 * Portions copyright (c) 2006 Nokia Corporation.  All rights reserved.

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser 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

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with this library; if not, write to the

 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,

 * Boston, MA 02111-1307, USA.

 */

/*

 * Modified by the GLib Team and others 1997-2000.  See the AUTHORS

 * file for a list of people on the GLib Team.  See the ChangeLog

 * files for a list of changes.  These files are distributed with

 * GLib at ftp://ftp.gtk.org/pub/gtk/. 

 */

#ifndef __G_DATE_H__

#define __G_DATE_H__

#include <_ansi.h>

#include <time.h>

#include <glib/gtypes.h>

#include <glib/gquark.h>

G_BEGIN_DECLS

/* GDate

 *

 * Date calculations (not time for now, to be resolved). These are a

 * mutant combination of Steffen Beyer's DateCalc routines

 * (http://www.perl.com/CPAN/authors/id/STBEY/) and Jon Trowbridge's

 * date routines (written for in-house software).  Written by Havoc

 * Pennington <hp@pobox.com>

 */

typedef gint32  GTime;

typedef guint16 GDateYear;

typedef guint8  GDateDay;   /* day of the month */

typedef struct _GDate GDate;

/* make struct tm known without having to include time.h */

struct tm;

/* enum used to specify order of appearance in parsed date strings */

typedef enum

{

  G_DATE_DAY   = 0,

  G_DATE_MONTH = 1,

  G_DATE_YEAR  = 2

} GDateDMY;

/* actual week and month values */

typedef enum

{

  G_DATE_BAD_WEEKDAY  = 0,

  G_DATE_MONDAY       = 1,

  G_DATE_TUESDAY      = 2,

  G_DATE_WEDNESDAY    = 3,

  G_DATE_THURSDAY     = 4,

  G_DATE_FRIDAY       = 5,

  G_DATE_SATURDAY     = 6,

  G_DATE_SUNDAY       = 7

} GDateWeekday;

typedef enum

{

  G_DATE_BAD_MONTH = 0,

  G_DATE_JANUARY   = 1,

  G_DATE_FEBRUARY  = 2,

  G_DATE_MARCH     = 3,

  G_DATE_APRIL     = 4,

  G_DATE_MAY       = 5,

  G_DATE_JUNE      = 6,

  G_DATE_JULY      = 7,

  G_DATE_AUGUST    = 8,

  G_DATE_SEPTEMBER = 9,

  G_DATE_OCTOBER   = 10,

  G_DATE_NOVEMBER  = 11,

  G_DATE_DECEMBER  = 12

} GDateMonth;

#define G_DATE_BAD_JULIAN 0U

#define G_DATE_BAD_DAY    0U

#define G_DATE_BAD_YEAR   0U

/* Note: directly manipulating structs is generally a bad idea, but

 * in this case it's an *incredibly* bad idea, because all or part

 * of this struct can be invalid at any given time. Use the functions,

 * or you will get hosed, I promise.

 */

struct _GDate

{

  guint julian_days : 32; /* julian days representation - we use a

                           *  bitfield hoping that 64 bit platforms

                           *  will pack this whole struct in one big

                           *  int

                           */

  guint julian : 1;    /* julian is valid */

  guint dmy    : 1;    /* dmy is valid */

  /* DMY representation */

  guint day    : 6;

  guint month  : 4;

  guint year   : 16;

};

/* g_date_new() returns an invalid date, you then have to _set() stuff

 * to get a usable object. You can also allocate a GDate statically,

 * then call g_date_clear() to initialize.

 */

IMPORT_C GDate*       g_date_new                   (void);

IMPORT_C GDate*       g_date_new_dmy               (GDateDay     day,

                                           GDateMonth   month,

                                           GDateYear    year);

IMPORT_C GDate*       g_date_new_julian            (guint32      julian_day);

IMPORT_C void         g_date_free                  (GDate       *date);

/* check g_date_valid() after doing an operation that might fail, like

 * _parse.  Almost all g_date operations are undefined on invalid

 * dates (the exceptions are the mutators, since you need those to

 * return to validity).

 */

IMPORT_C gboolean     g_date_valid                 (const GDate *date);

IMPORT_C gboolean     g_date_valid_day             (GDateDay     day) G_GNUC_CONST;

IMPORT_C gboolean     g_date_valid_month           (GDateMonth month) G_GNUC_CONST;

IMPORT_C gboolean     g_date_valid_year            (GDateYear  year) G_GNUC_CONST;

IMPORT_C gboolean     g_date_valid_weekday         (GDateWeekday weekday) G_GNUC_CONST;

IMPORT_C gboolean     g_date_valid_julian          (guint32 julian_date) G_GNUC_CONST;

IMPORT_C gboolean     g_date_valid_dmy             (GDateDay     day,

                                           GDateMonth   month,

                                           GDateYear    year) G_GNUC_CONST;

IMPORT_C GDateWeekday g_date_get_weekday           (const GDate *date);

IMPORT_C GDateMonth   g_date_get_month             (const GDate *date);

IMPORT_C GDateYear    g_date_get_year              (const GDate *date);

IMPORT_C GDateDay     g_date_get_day               (const GDate *date);

IMPORT_C guint32      g_date_get_julian            (const GDate *date);

IMPORT_C guint        g_date_get_day_of_year       (const GDate *date);

/* First monday/sunday is the start of week 1; if we haven't reached

 * that day, return 0. These are not ISO weeks of the year; that

 * routine needs to be added.

 * these functions return the number of weeks, starting on the

 * corrsponding day

 */

IMPORT_C guint        g_date_get_monday_week_of_year (const GDate *date);

IMPORT_C guint        g_date_get_sunday_week_of_year (const GDate *date);

IMPORT_C guint        g_date_get_iso8601_week_of_year (const GDate *date);

/* If you create a static date struct you need to clear it to get it

 * in a sane state before use. You can clear a whole array at

 * once with the ndates argument.

 */

IMPORT_C void         g_date_clear                 (GDate       *date,

                                           guint        n_dates);

/* The parse routine is meant for dates typed in by a user, so it

 * permits many formats but tries to catch common typos. If your data

 * needs to be strictly validated, it is not an appropriate function.

 */

IMPORT_C void         g_date_set_parse             (GDate       *date,

                                           const gchar *str);

IMPORT_C void         g_date_set_time              (GDate       *date,

					   time_t       timet);

IMPORT_C void         g_date_set_time_val          (GDate       *date,

					   GTimeVal    *timeval);

#ifndef G_DISABLE_DEPRECATED

IMPORT_C void         g_date_set_time              (GDate       *date,

                                           GTime        time_);

#endif

IMPORT_C void         g_date_set_month             (GDate       *date,

                                           GDateMonth   month);

IMPORT_C void         g_date_set_day               (GDate       *date,

                                           GDateDay     day);

IMPORT_C void         g_date_set_year              (GDate       *date,

                                           GDateYear    year);

IMPORT_C void         g_date_set_dmy               (GDate       *date,

                                           GDateDay     day,

                                           GDateMonth   month,

                                           GDateYear    y);

IMPORT_C void         g_date_set_julian            (GDate       *date,

                                           guint32      julian_date);

IMPORT_C gboolean     g_date_is_first_of_month     (const GDate *date);

IMPORT_C gboolean     g_date_is_last_of_month      (const GDate *date);

/* To go forward by some number of weeks just go forward weeks*7 days */

IMPORT_C void         g_date_add_days              (GDate       *date,

                                           guint        n_days);

IMPORT_C void         g_date_subtract_days         (GDate       *date,

                                           guint        n_days);

/* If you add/sub months while day > 28, the day might change */

IMPORT_C void         g_date_add_months            (GDate       *date,

                                           guint        n_months);

IMPORT_C void         g_date_subtract_months       (GDate       *date,

                                           guint        n_months);

/* If it's feb 29, changing years can move you to the 28th */

IMPORT_C void         g_date_add_years             (GDate       *date,

                                           guint        n_years);

IMPORT_C void         g_date_subtract_years        (GDate       *date,

                                           guint        n_years);

IMPORT_C gboolean     g_date_is_leap_year          (GDateYear    year) G_GNUC_CONST;

IMPORT_C guint8       g_date_get_days_in_month     (GDateMonth   month,

                                           GDateYear    year) G_GNUC_CONST;

IMPORT_C guint8       g_date_get_monday_weeks_in_year  (GDateYear    year) G_GNUC_CONST;

IMPORT_C guint8       g_date_get_sunday_weeks_in_year  (GDateYear    year) G_GNUC_CONST;

/* Returns the number of days between the two dates.  If date2 comes

   before date1, a negative value is return. */

IMPORT_C gint         g_date_days_between          (const GDate *date1,

					   const GDate *date2);

/* qsort-friendly (with a cast...) */

IMPORT_C gint         g_date_compare               (const GDate *lhs,

                                           const GDate *rhs);

IMPORT_C void         g_date_to_struct_tm          (const GDate *date,

                                           struct tm   *tm);

IMPORT_C void         g_date_clamp                 (GDate *date,

					   const GDate *min_date,

					   const GDate *max_date);

/* Swap date1 and date2's values if date1 > date2. */

IMPORT_C void         g_date_order                 (GDate *date1, GDate *date2);

/* Just like strftime() except you can only use date-related formats.

 *   Using a time format is undefined.

 */

IMPORT_C gsize        g_date_strftime              (gchar       *s,

                                           gsize        slen,

                                           const gchar *format,

                                           const GDate *date);

#ifndef G_DISABLE_DEPRECATED

#define g_date_weekday 			g_date_get_weekday

#define g_date_month 			g_date_get_month

#define g_date_year 			g_date_get_year

#define g_date_day 			g_date_get_day

#define g_date_julian 			g_date_get_julian

#define g_date_day_of_year 		g_date_get_day_of_year

#define g_date_monday_week_of_year 	g_date_get_monday_week_of_year

#define g_date_sunday_week_of_year 	g_date_get_sunday_week_of_year

#define g_date_days_in_month 		g_date_get_days_in_month

#define g_date_monday_weeks_in_year 	g_date_get_monday_weeks_in_year

#define g_date_sunday_weeks_in_year	g_date_get_sunday_weeks_in_year

#endif /* G_DISABLE_DEPRECATED */

G_END_DECLS

#endif /* __G_DATE_H__ */