Added wxCLIP_SIBLINGS. CVS also seems to think lots of other files need updating.

[wxWidgets.git] / include / wx / datetime.h

diff --git a/include/wx/datetime.h b/include/wx/datetime.h
index bf7cab1fcc56dfc2dcb1d759326a5aae696da220..688b2debf4192b90b632494796a0edea13aa11d3 100644 (file)
--- a/include/wx/datetime.h
+++ b/include/wx/datetime.h
@@ -10,8 +10,8 @@
 // Licence:     wxWindows license
 /////////////////////////////////////////////////////////////////////////////
 
 // Licence:     wxWindows license
 /////////////////////////////////////////////////////////////////////////////
 

-#ifndef _WX_TIME_H
-#define _WX_TIME_H
+#ifndef _WX_DATETIME_H
+#define _WX_DATETIME_H

 
 #ifdef __GNUG__
     #pragma interface "datetime.h"
 
 #ifdef __GNUG__
     #pragma interface "datetime.h"


@@ -26,16 +26,28 @@ class WXDLLEXPORT wxDateTime;
 class WXDLLEXPORT wxTimeSpan;
 class WXDLLEXPORT wxDateSpan;
 
 class WXDLLEXPORT wxTimeSpan;
 class WXDLLEXPORT wxDateSpan;
 

+// don't use inline functions in debug builds - we don't care about
+// performances and this only leads to increased rebuild time (because every
+// time an inline method is changed, all files including the header must be
+// rebuilt)
+// For Mingw32, causes a link error.
+#if defined( __WXDEBUG__) && !defined(__MINGW32__)
+    #undef inline
+    #define inline
+#endif // Debug
+

 /*
 /*

- * TODO Well, everything :-)
+ * TODO

  *
  *

- * 1. Time zones with minutes (make wxTimeZone a class)
- * 2. getdate() function like under Solaris
- * 3. text conversion for wxDateSpan
+ * + 1. Time zones with minutes (make TimeZone a class)
+ * ? 2. getdate() function like under Solaris
+ * + 3. text conversion for wxDateSpan
+ * + 4. pluggable modules for the workdays calculations
+ *   5. wxDateTimeHolidayAuthority for Easter and other christian feasts

  */
 
 /*
  */
 
 /*

-  The three classes declared in this header represent:
+  The three (main) classes declared in this header represent:

 
   1. An absolute moment in the time (wxDateTime)
   2. A difference between two moments in the time, positive or negative
 
   1. An absolute moment in the time (wxDateTime)
   2. A difference between two moments in the time, positive or negative


@@ -53,25 +65,46 @@ class WXDLLEXPORT wxDateSpan;
   wxTimeSpan + wxTimeSpan = wxTimeSpan
   wxDateSpan + wxDateSpan = wxDateSpan
 
   wxTimeSpan + wxTimeSpan = wxTimeSpan
   wxDateSpan + wxDateSpan = wxDateSpan
 

-  substraction
+  subtraction

   ------------
   wxDateTime - wxDateTime = wxTimeSpan
   ------------
   wxDateTime - wxDateTime = wxTimeSpan

+  wxDateTime - wxTimeSpan = wxDateTime
+  wxDateTime - wxDateSpan = wxDateTime

   wxTimeSpan - wxTimeSpan = wxTimeSpan
   wxDateSpan - wxDateSpan = wxDateSpan
 
   multiplication
   --------------
   wxTimeSpan * number = wxTimeSpan
   wxTimeSpan - wxTimeSpan = wxTimeSpan
   wxDateSpan - wxDateSpan = wxDateSpan
 
   multiplication
   --------------
   wxTimeSpan * number = wxTimeSpan

+  number * wxTimeSpan = wxTimeSpan

   wxDateSpan * number = wxDateSpan
   wxDateSpan * number = wxDateSpan

+  number * wxDateSpan = wxDateSpan

 
   unitary minus
   -------------
   -wxTimeSpan = wxTimeSpan
   -wxDateSpan = wxDateSpan
 
   unitary minus
   -------------
   -wxTimeSpan = wxTimeSpan
   -wxDateSpan = wxDateSpan

+
+  For each binary operation OP (+, -, *) we have the following operatorOP=() as
+  a method and the method with a symbolic name OPER (Add, Subtract, Multiply)
+  as a synonym for it and another const method with the same name which returns
+  the changed copy of the object and operatorOP() as a global function which is
+  implemented in terms of the const version of OPEN. For the unary - we have
+  operator-() as a method, Neg() as synonym for it and Negate() which returns
+  the copy of the object with the changed sign.

 */
 
 */
 

+// an invalid/default date time object which may be used as the default
+// argument for arguments of type wxDateTime; it is also returned by all
+// functions returning wxDateTime on failure (this is why it is also called
+// wxInvalidDateTime)
+class WXDLLEXPORT wxDateTime;
+
+WXDLLEXPORT_DATA(extern wxDateTime&) wxDefaultDateTime;
+#define wxInvalidDateTime wxDefaultDateTime
+

 // ----------------------------------------------------------------------------
 // ----------------------------------------------------------------------------

-// This class represents an absolute moment in the time
+// wxDateTime represents an absolute moment in the time

 // ----------------------------------------------------------------------------
 
 class WXDLLEXPORT wxDateTime
 // ----------------------------------------------------------------------------
 
 class WXDLLEXPORT wxDateTime


@@ -80,13 +113,16 @@ public:
     // types
     // ------------------------------------------------------------------------
 
     // types
     // ------------------------------------------------------------------------
 

-        // a small unsigned integer type for storing things like seconds, days
-        // of the week, &c. It should be at least short (i.e. not char) to
-        // contain the number of milliseconds - it may also be 'int' because
-        // there is no size penalty associated with it in our code, we don't
-        // store any data in this format
+        // a small unsigned integer type for storing things like minutes,
+        // seconds &c. It should be at least short (i.e. not char) to contain
+        // the number of milliseconds - it may also be 'int' because there is
+        // no size penalty associated with it in our code, we don't store any
+        // data in this format

     typedef unsigned short wxDateTime_t;
 
     typedef unsigned short wxDateTime_t;
 

+    // constants
+    // ------------------------------------------------------------------------
+

         // the timezones
     enum TZ
     {
         // the timezones
     enum TZ
     {


@@ -106,10 +142,45 @@ public:
         // Note that GMT12 and GMT_12 are not the same: there is a difference
         // of exactly one day between them
 
         // Note that GMT12 and GMT_12 are not the same: there is a difference
         // of exactly one day between them
 

-        // Universal Coordinated Time
+        // some symbolic names for TZ
+
+        // Europe
+        WET = GMT0,                         // Western Europe Time
+        WEST = GMT1,                        // Western Europe Summer Time
+        CET = GMT1,                         // Central Europe Time
+        CEST = GMT2,                        // Central Europe Summer Time
+        EET = GMT2,                         // Eastern Europe Time
+        EEST = GMT3,                        // Eastern Europe Summer Time
+        MSK = GMT3,                         // Moscow Time
+        MSD = GMT4,                         // Moscow Summer Time
+
+        // US and Canada
+        AST = GMT_4,                        // Atlantic Standard Time
+        ADT = GMT_3,                        // Atlantic Daylight Time
+        EST = GMT_5,                        // Eastern Standard Time
+        EDT = GMT_4,                        // Eastern Daylight Saving Time
+        CST = GMT_6,                        // Central Standard Time
+        CDT = GMT_5,                        // Central Daylight Saving Time
+        MST = GMT_7,                        // Mountain Standard Time
+        MDT = GMT_6,                        // Mountain Daylight Saving Time
+        PST = GMT_8,                        // Pacific Standard Time
+        PDT = GMT_7,                        // Pacific Daylight Saving Time
+        HST = GMT_10,                       // Hawaiian Standard Time
+        AKST = GMT_9,                       // Alaska Standard Time
+        AKDT = GMT_8,                       // Alaska Daylight Saving Time
+
+        // Australia
+
+        A_WST = GMT8,                       // Western Standard Time
+        A_CST = GMT12 + 1,                  // Central Standard Time (+9.5)
+        A_EST = GMT10,                      // Eastern Standard Time
+        A_ESST = GMT11,                     // Eastern Summer Time
+
+        // TODO add more symbolic timezone names here
+
+        // Universal Coordinated Time = the new and politically correct name
+        // for GMT

         UTC = GMT0
         UTC = GMT0

-
-        // TODO add symbolic names for TZ (EST, MET, ...)?

     };
 
         // the calendar systems we know about: notice that it's valid (for
     };
 
         // the calendar systems we know about: notice that it's valid (for


@@ -251,10 +322,22 @@ public:
     {
         Country_Unknown, // no special information for this country
         Country_Default, // set the default country with SetCountry() method
     {
         Country_Unknown, // no special information for this country
         Country_Default, // set the default country with SetCountry() method

+                         // or use the default country with any other

 
         // TODO add more countries (for this we must know about DST and/or
         //      holidays for this country)
 
         // TODO add more countries (for this we must know about DST and/or
         //      holidays for this country)

+
+        // Western European countries: we assume that they all follow the same
+        // DST rules (true or false?)
+        Country_WesternEurope_Start,
+        Country_EEC = Country_WesternEurope_Start,

         France,
         France,

+        Germany,
+        UK,
+        Country_WesternEurope_End = UK,
+
+        Russia,
+

         USA
     };
 
         USA
     };
 


@@ -276,22 +359,57 @@ public:
         Inv_Year = SHRT_MIN    // should hold in wxDateTime_t
     };
 
         Inv_Year = SHRT_MIN    // should hold in wxDateTime_t
     };
 

+        // flags for GetWeekDayName and GetMonthName
+    enum NameFlags
+    {
+        Name_Full = 0x01,       // return full name
+        Name_Abbr = 0x02        // return abbreviated name
+    };
+
+        // flags for GetWeekOfYear and GetWeekOfMonth
+    enum WeekFlags
+    {
+        Default_First,   // Sunday_First for US, Monday_First for the rest
+        Monday_First,    // week starts with a Monday
+        Sunday_First     // week starts with a Sunday
+    };
+

     // helper classes
     // ------------------------------------------------------------------------
 
     // helper classes
     // ------------------------------------------------------------------------
 

+        // a class representing a time zone: basicly, this is just an offset
+        // (in seconds) from GMT
+    class WXDLLEXPORT TimeZone
+    {
+    public:
+        TimeZone(TZ tz);
+        TimeZone(wxDateTime_t offset = 0) { m_offset = offset; }
+
+        long GetOffset() const { return m_offset; }
+
+    private:
+        // offset for this timezone from GMT in seconds
+        long m_offset;
+    };
+

         // standard struct tm is limited to the years from 1900 (because
         // tm_year field is the offset from 1900), so we use our own struct
         // instead to represent broken down time
         // standard struct tm is limited to the years from 1900 (because
         // tm_year field is the offset from 1900), so we use our own struct
         // instead to represent broken down time

-    struct Tm
+        //
+        // NB: this struct should always be kept normalized (i.e. mon should
+        //     be < 12, 1 <= day <= 31 &c), so use AddMonths(), AddDays()
+        //     instead of modifying the member fields directly!
+    struct WXDLLEXPORT Tm

     {
     {

-        wxDateTime_t sec, min, hour,
-                     mday, mon, year;
+        wxDateTime_t msec, sec, min, hour, mday;
+        Month mon;
+        int year;

 
         // default ctor inits the object to an invalid value
         Tm();
 
 
         // default ctor inits the object to an invalid value
         Tm();
 

-        // ctor from struct tm
-        Tm(const struct tm& tm);
+        // ctor from struct tm and the timezone
+        Tm(const struct tm& tm, const TimeZone& tz);

 
         // check that the given date/time is valid (in Gregorian calendar)
         bool IsValid() const;
 
         // check that the given date/time is valid (in Gregorian calendar)
         bool IsValid() const;


@@ -305,37 +423,35 @@ public:
             return (WeekDay)wday;
         }
 
             return (WeekDay)wday;
         }
 

+        // add the given number of months to the date keeping it normalized
+        void AddMonths(int monDiff);
+
+        // add the given number of months to the date keeping it normalized
+        void AddDays(int dayDiff);
+

     private:
         // compute the weekday from other fields
         void ComputeWeekDay();
 
     private:
         // compute the weekday from other fields
         void ComputeWeekDay();
 

+        // the timezone we correspond to
+        TimeZone m_tz;
+

         // these values can't be accessed directly because they're not always
         // computed and we calculate them on demand
         wxDateTime_t wday, yday;
     };
 
         // these values can't be accessed directly because they're not always
         // computed and we calculate them on demand
         wxDateTime_t wday, yday;
     };
 

-        // a class representing a time zone: basicly, this is just an offset
-        // (in minutes) from GMT
-    class TimeZone
-    {
-    public:
-        TimeZone(TZ tz);
-        TimeZone(wxDateTime_t offset) { m_offset = offset; }
-
-        wxDateTime_t GetOffset() const { return m_offset; }
-
-    private:
-        // offset for this timezone from GMT in minutes
-        wxDateTime_t m_offset;
-    };
-

     // static methods
     // ------------------------------------------------------------------------
 
         // set the current country
     static void SetCountry(Country country);
         // get the current country
     // static methods
     // ------------------------------------------------------------------------
 
         // set the current country
     static void SetCountry(Country country);
         // get the current country

-    static inline Country GetCountry();
+    static Country GetCountry();
+
+        // return TRUE if the country is a West European one (in practice,
+        // this means that the same DST rules as for EEC apply)
+    static bool IsWestEuropeanCountry(Country country = Country_Default);

 
         // return the current year
     static int GetCurrentYear(Calendar cal = Gregorian);
 
         // return the current year
     static int GetCurrentYear(Calendar cal = Gregorian);


@@ -350,7 +466,10 @@ public:
     static Month GetCurrentMonth(Calendar cal = Gregorian);
 
         // returns TRUE if the given year is a leap year in the given calendar
     static Month GetCurrentMonth(Calendar cal = Gregorian);
 
         // returns TRUE if the given year is a leap year in the given calendar

-    static bool IsLeapYear(int year, Calendar cal = Gregorian);
+    static bool IsLeapYear(int year = Inv_Year, Calendar cal = Gregorian);
+
+        // get the century (19 for 1999, 20 for 2000 and -5 for 492 BC)
+    static int GetCentury(int year = Inv_Year);

 
         // returns the number of days in this year (356 or 355 for Gregorian
         // calendar usually :-)
 
         // returns the number of days in this year (356 or 355 for Gregorian
         // calendar usually :-)


@@ -364,42 +483,64 @@ public:
 
         // get the full (default) or abbreviated month name in the current
         // locale, returns empty string on error
 
         // get the full (default) or abbreviated month name in the current
         // locale, returns empty string on error

-    static wxString GetMonthName(Month month, bool abbr = FALSE);
+    static wxString GetMonthName(Month month,
+                                 NameFlags flags = Name_Full);

 
         // get the full (default) or abbreviated weekday name in the current
         // locale, returns empty string on error
 
         // get the full (default) or abbreviated weekday name in the current
         // locale, returns empty string on error

-    static wxString GetWeekDayName(WeekDay weekday, bool abbr = FALSE);
+    static wxString GetWeekDayName(WeekDay weekday,
+                                   NameFlags flags = Name_Full);
+
+        // get the AM and PM strings in the current locale (may be empty)
+    static void GetAmPmStrings(wxString *am, wxString *pm);
+
+        // return TRUE if the given country uses DST for this year
+    static bool IsDSTApplicable(int year = Inv_Year,
+                                Country country = Country_Default);

 
         // get the beginning of DST for this year, will return invalid object
         // if no DST applicable in this year. The default value of the
         // parameter means to take the current year.
 
         // get the beginning of DST for this year, will return invalid object
         // if no DST applicable in this year. The default value of the
         // parameter means to take the current year.

-    static wxDateTime GetBeginDST(int year = Inv_Year);
+    static wxDateTime GetBeginDST(int year = Inv_Year,
+                                  Country country = Country_Default);

         // get the end of DST for this year, will return invalid object
         // if no DST applicable in this year. The default value of the
         // parameter means to take the current year.
         // get the end of DST for this year, will return invalid object
         // if no DST applicable in this year. The default value of the
         // parameter means to take the current year.

-    static wxDateTime GetEndDST(int year = Inv_Year);
+    static wxDateTime GetEndDST(int year = Inv_Year,
+                                Country country = Country_Default);

 
         // return the wxDateTime object for the current time
     static inline wxDateTime Now();
 
 
         // return the wxDateTime object for the current time
     static inline wxDateTime Now();
 

+        // return the wxDateTime object for the current time with millisecond
+        // precision (if available on this platform)
+    static wxDateTime UNow();
+
+        // return the wxDateTime object for today midnight: i.e. as Now() but
+        // with time set to 0
+    static inline wxDateTime Today();
+

     // constructors: you should test whether the constructor succeeded with
     // IsValid() function. The values Inv_Month and Inv_Year for the
     // parameters mean take current month and/or year values.
     // constructors: you should test whether the constructor succeeded with
     // IsValid() function. The values Inv_Month and Inv_Year for the
     // parameters mean take current month and/or year values.

-    //
-    // All new wxDateTime correspond to the local time, use ToUTC() or
-    // MakeUTC() to get the time in UTC/GMT.

     // ------------------------------------------------------------------------
 
         // default ctor does not initialize the object, use Set()!
     wxDateTime() { }
 
         // from time_t: seconds since the Epoch 00:00:00 UTC, Jan 1, 1970)
     // ------------------------------------------------------------------------
 
         // default ctor does not initialize the object, use Set()!
     wxDateTime() { }
 
         // from time_t: seconds since the Epoch 00:00:00 UTC, Jan 1, 1970)

+#if (!(defined(__VISAGECPP__) && __IBMCPP__ >= 400))
+// VA C++ confuses this with wxDateTime(double jdn) thinking it is a duplicate declaration

     inline wxDateTime(time_t timet);
     inline wxDateTime(time_t timet);

+#endif

         // from broken down time/date (only for standard Unix range)
     inline wxDateTime(const struct tm& tm);
         // from broken down time/date (any range)
     inline wxDateTime(const Tm& tm);
 
         // from broken down time/date (only for standard Unix range)
     inline wxDateTime(const struct tm& tm);
         // from broken down time/date (any range)
     inline wxDateTime(const Tm& tm);
 

+        // from JDN (beware of rounding errors)
+    inline wxDateTime(double jdn);
+

         // from separate values for each component, date set to today
     inline wxDateTime(wxDateTime_t hour,
                       wxDateTime_t minute = 0,
         // from separate values for each component, date set to today
     inline wxDateTime(wxDateTime_t hour,
                       wxDateTime_t minute = 0,


@@ -426,8 +567,11 @@ public:
         // set to the current time
     inline wxDateTime& SetToCurrent();
 
         // set to the current time
     inline wxDateTime& SetToCurrent();
 

+#if (!(defined(__VISAGECPP__) && __IBMCPP__ >= 400))
+// VA C++ confuses this with wxDateTime(double jdn) thinking it is a duplicate declaration

         // set to given time_t value
     inline wxDateTime& Set(time_t timet);
         // set to given time_t value
     inline wxDateTime& Set(time_t timet);

+#endif

 
         // set to given broken down time/date
     wxDateTime& Set(const struct tm& tm);
 
         // set to given broken down time/date
     wxDateTime& Set(const struct tm& tm);


@@ -435,6 +579,9 @@ public:
         // set to given broken down time/date
     inline wxDateTime& Set(const Tm& tm);
 
         // set to given broken down time/date
     inline wxDateTime& Set(const Tm& tm);
 

+        // set to given JDN (beware of rounding errors)
+    wxDateTime& Set(double jdn);
+

         // set to given time, date = today
     wxDateTime& Set(wxDateTime_t hour,
                     wxDateTime_t minute = 0,
         // set to given time, date = today
     wxDateTime& Set(wxDateTime_t hour,
                     wxDateTime_t minute = 0,


@@ -484,30 +631,59 @@ public:
         // default assignment operator is ok
 
     // calendar calculations (functions which set the date only leave the time
         // default assignment operator is ok
 
     // calendar calculations (functions which set the date only leave the time

-    // unchanged, e.g. don't explictly zero it)
+    // unchanged, e.g. don't explictly zero it): SetXXX() functions modify the
+    // object itself, GetXXX() ones return a new object.

     // ------------------------------------------------------------------------
 
     // ------------------------------------------------------------------------
 

+        // set to the given week day in the same week as this one
+    wxDateTime& SetToWeekDayInSameWeek(WeekDay weekday);
+    inline wxDateTime GetWeekDayInSameWeek(WeekDay weekday) const;
+
+        // set to the next week day following this one
+    wxDateTime& SetToNextWeekDay(WeekDay weekday);
+    inline wxDateTime GetNextWeekDay(WeekDay weekday) const;
+
+        // set to the previous week day before this one
+    wxDateTime& SetToPrevWeekDay(WeekDay weekday);
+    inline wxDateTime GetPrevWeekDay(WeekDay weekday) const;
+

         // set to Nth occurence of given weekday in the given month of the
         // given year (time is set to 0), return TRUE on success and FALSE on
         // failure. n may be positive (1..5) or negative to count from the end
         // of the month (see helper function SetToLastWeekDay())
     bool SetToWeekDay(WeekDay weekday,
                       int n = 1,
         // set to Nth occurence of given weekday in the given month of the
         // given year (time is set to 0), return TRUE on success and FALSE on
         // failure. n may be positive (1..5) or negative to count from the end
         // of the month (see helper function SetToLastWeekDay())
     bool SetToWeekDay(WeekDay weekday,
                       int n = 1,

-                      wxDateTime_t month = Inv_Month,
+                      Month month = Inv_Month,

                       int year = Inv_Year);
                       int year = Inv_Year);

+    inline wxDateTime GetWeekDay(WeekDay weekday,
+                                 int n = 1,
+                                 Month month = Inv_Month,
+                                 int year = Inv_Year) const;

 
         // sets to the last weekday in the given month, year
     inline bool SetToLastWeekDay(WeekDay weekday,
 
         // sets to the last weekday in the given month, year
     inline bool SetToLastWeekDay(WeekDay weekday,

-                                 wxDateTime_t month = Inv_Month,
+                                 Month month = Inv_Month,

                                  int year = Inv_Year);
                                  int year = Inv_Year);

+    inline wxDateTime GetLastWeekDay(WeekDay weekday,
+                                     Month month = Inv_Month,
+                                     int year = Inv_Year);

 
         // sets the date to the given day of the given week in the year,
         // returns TRUE on success and FALSE if given date doesn't exist (e.g.
         // numWeek is > 53)
     bool SetToTheWeek(wxDateTime_t numWeek, WeekDay weekday = Mon);
 
         // sets the date to the given day of the given week in the year,
         // returns TRUE on success and FALSE if given date doesn't exist (e.g.
         // numWeek is > 53)
     bool SetToTheWeek(wxDateTime_t numWeek, WeekDay weekday = Mon);

+    inline wxDateTime GetWeek(wxDateTime_t numWeek, WeekDay weekday = Mon) const;

 
 

-        // get the century (19 for 1999, 20 for 2000 and -5 for 492 BC)
-    int GetCentury() const;
+        // sets the date to the last day of the given (or current) month or the
+        // given (or current) year
+    wxDateTime& SetToLastMonthDay(Month month = Inv_Month,
+                                  int year = Inv_Year);
+    inline wxDateTime GetLastMonthDay(Month month = Inv_Month,
+                                      int year = Inv_Year) const;
+
+        // sets to the given year day (1..365 or 366)
+    wxDateTime& SetToYearDay(wxDateTime_t yday);
+    inline wxDateTime GetYearDay(wxDateTime_t yday) const;

 
         // The definitions below were taken verbatim from
         //
 
         // The definitions below were taken verbatim from
         //


@@ -531,31 +707,51 @@ public:
         // of days relative to a base date of December 31 of the year 0. Thus
         // January 1 of the year 1 is Rata Die day 1.
 
         // of days relative to a base date of December 31 of the year 0. Thus
         // January 1 of the year 1 is Rata Die day 1.
 

-        // get the Julian Day number
-    long GetJulianDay() const;
+        // get the Julian Day number (the fractional part specifies the time of
+        // the day, related to noon - beware of rounding errors!)
+    double GetJulianDayNumber() const;
+    double GetJDN() const { return GetJulianDayNumber(); }
+
+        // get the Modified Julian Day number: it is equal to JDN - 2400000.5
+        // and so integral MJDs correspond to the midnights (and not noons).
+        // MJD 0 is Nov 17, 1858
+    double GetModifiedJulianDayNumber() const { return GetJDN() - 2400000.5; }
+    double GetMJD() const { return GetModifiedJulianDayNumber(); }

 
         // get the Rata Die number
 
         // get the Rata Die number

-    long GetRataDie() const;
+    double GetRataDie() const;

 
         // TODO algorithms for calculating some important dates, such as
         //      religious holidays (Easter...) or moon/solar eclipses? Some
         //      algorithms can be found in the calendar FAQ
 
 
         // TODO algorithms for calculating some important dates, such as
         //      religious holidays (Easter...) or moon/solar eclipses? Some
         //      algorithms can be found in the calendar FAQ
 

-    // timezone stuff: by default, we always work with local times, to get
-    // anything else, it should be requested explicitly
+    // timezone stuff: a wxDateTime object constructed using given
+    // day/month/year/hour/min/sec values correspond to this moment in local
+    // time. Using the functions below, it may be converted to another time
+    // zone (for example, the Unix epoch is wxDateTime(1, Jan, 1970).ToGMT())
+    //
+    // these functions try to handle DST internally, but there is no magical
+    // way to know all rules for it in all countries in the world, so if the
+    // program can handle it itself (or doesn't want to handle it at all for
+    // whatever reason), the DST handling can be disabled with noDST.
+    //
+    // Converting to the local time zone doesn't do anything.

     // ------------------------------------------------------------------------
 
     // ------------------------------------------------------------------------
 

-        // get the time corresponding to this one in UTC/GMT
-    wxDateTime ToUTC() const;
-    wxDateTime ToGMT() const { return ToUTC(); }
+        // transform to any given timezone
+    inline wxDateTime ToTimezone(const TimeZone& tz, bool noDST = FALSE) const;
+    wxDateTime& MakeTimezone(const TimeZone& tz, bool noDST = FALSE);

 
 

-        // transform this object to UTC/GMT
-    wxDateTime& MakeUTC();
-    wxDateTime& MakeGMT() { return MakeUTC(); }
+        // transform to GMT/UTC
+    wxDateTime ToGMT(bool noDST = FALSE) const { return ToTimezone(GMT0, noDST); }
+    wxDateTime& MakeGMT(bool noDST = FALSE) { return MakeTimezone(GMT0, noDST); }

 
 

-        // generic version: transform time to any given timezone
-    wxDateTime ToTimezone(const TimeZone& tz);
-    wxDateTime& MakeTimezone(const TimeZone& tz);
+        // is daylight savings time in effect at this moment according to the
+        // rules of the specified country?
+        //
+        // Return value is > 0 if DST is in effect, 0 if it is not and -1 if
+        // the information is not available (this is compatible with ANSI C)
+    int IsDST(Country country = Country_Default) const;

 
     // accessors: many of them take the timezone parameter which indicates the
     // timezone for which to make the calculations and the default value means
 
     // accessors: many of them take the timezone parameter which indicates the
     // timezone for which to make the calculations and the default value means


@@ -564,71 +760,74 @@ public:
     // result of timezone shift)
     // ------------------------------------------------------------------------
 
     // result of timezone shift)
     // ------------------------------------------------------------------------
 

-        // is the date valid (FALSE for uninitialized objects as well as after
-        // the functions which failed to convert the date to supported range)
-    inline bool IsValid() const { return this != &ms_InvDateTime; }
+        // is the date valid (TRUE even for non initialized objects)?
+    inline bool IsValid() const { return this != &wxInvalidDateTime; }

 
 

-        // get the broken down date/time representation
-    Tm GetTm() const;
+        // get the broken down date/time representation in the given timezone
+        //
+        // If you wish to get several time components (day, month and year),
+        // consider getting the whole Tm strcuture first and retrieving the
+        // value from it - this is much more efficient
+    Tm GetTm(const TimeZone& tz = Local) const;

 
         // get the number of seconds since the Unix epoch - returns (time_t)-1
         // if the value is out of range
     inline time_t GetTicks() const;
 
         // get the year (returns Inv_Year if date is invalid)
 
         // get the number of seconds since the Unix epoch - returns (time_t)-1
         // if the value is out of range
     inline time_t GetTicks() const;
 
         // get the year (returns Inv_Year if date is invalid)

-    int GetYear() const { return GetTm().year; }
+    int GetYear(const TimeZone& tz = Local) const
+            { return GetTm(tz).year; }

         // get the month (Inv_Month if date is invalid)
         // get the month (Inv_Month if date is invalid)

-    Month GetMonth() const { return (Month)GetTm().mon; }
+    Month GetMonth(const TimeZone& tz = Local) const
+            { return (Month)GetTm(tz).mon; }

         // get the month day (in 1..31 range, 0 if date is invalid)
         // get the month day (in 1..31 range, 0 if date is invalid)

-    wxDateTime_t GetDay() const { return GetTm().mday; }
+    wxDateTime_t GetDay(const TimeZone& tz = Local) const
+            { return GetTm(tz).mday; }

         // get the day of the week (Inv_WeekDay if date is invalid)
         // get the day of the week (Inv_WeekDay if date is invalid)

-    WeekDay GetDayOfWeek() const { return GetTm().GetWeekDay(); }
+    WeekDay GetWeekDay(const TimeZone& tz = Local) const
+            { return GetTm(tz).GetWeekDay(); }

         // get the hour of the day
         // get the hour of the day

-    wxDateTime_t GetHour() const { return GetTm().hour; }
+    wxDateTime_t GetHour(const TimeZone& tz = Local) const
+            { return GetTm(tz).hour; }

         // get the minute
         // get the minute

-    wxDateTime_t GetMinute() const { return GetTm().min; }
+    wxDateTime_t GetMinute(const TimeZone& tz = Local) const
+            { return GetTm(tz).min; }

         // get the second
         // get the second

-    wxDateTime_t GetSecond() const { return GetTm().sec; }
+    wxDateTime_t GetSecond(const TimeZone& tz = Local) const
+            { return GetTm(tz).sec; }

         // get milliseconds
         // get milliseconds

-    wxDateTime_t GetMillisecond() const { return m_time.GetLo() % 1000; }
+    wxDateTime_t GetMillisecond(const TimeZone& tz = Local) const
+            { return GetTm(tz).msec; }

 
         // get the day since the year start (1..366, 0 if date is invalid)
 
         // get the day since the year start (1..366, 0 if date is invalid)

-    wxDateTime_t GetDayOfYear() const;
-        // get the week number since the year start (1..52, 0 if date is
+    wxDateTime_t GetDayOfYear(const TimeZone& tz = Local) const;
+        // get the week number since the year start (1..52 or 53, 0 if date is

         // invalid)
         // invalid)

-    wxDateTime_t GetWeekOfYear() const;
+    wxDateTime_t GetWeekOfYear(WeekFlags flags = Monday_First,
+                               const TimeZone& tz = Local) const;
+        // get the week number since the month start (1..5, 0 if date is
+        // invalid)
+    wxDateTime_t GetWeekOfMonth(WeekFlags flags = Monday_First,
+                                const TimeZone& tz = Local) const;

 
         // is this date a work day? This depends on a country, of course,
         // because the holidays are different in different countries
 
         // is this date a work day? This depends on a country, of course,
         // because the holidays are different in different countries

-    bool IsWorkDay(Country country = Country_Default,
-                   TimeZone zone = Local) const;
+    bool IsWorkDay(Country country = Country_Default) const;

 
         // is this date later than Gregorian calendar introduction for the
         // given country (see enum GregorianAdoption)?
         //
 
         // is this date later than Gregorian calendar introduction for the
         // given country (see enum GregorianAdoption)?
         //

-        // NB: this function shouldn't be considered as absolute authoiruty in
+        // NB: this function shouldn't be considered as absolute authority in

         //     the matter. Besides, for some countries the exact date of
         //     adoption of the Gregorian calendar is simply unknown.
     bool IsGregorianDate(GregorianAdoption country = Gr_Standard) const;
 
         //     the matter. Besides, for some countries the exact date of
         //     adoption of the Gregorian calendar is simply unknown.
     bool IsGregorianDate(GregorianAdoption country = Gr_Standard) const;
 

-        // is daylight savings time in effect at this moment?
-        //
-        // Return value is > 0 if DST is in effect, 0 if it is not and -1 if
-        // the information is not available (this is compatible with ANSI C)
-    int IsDST(Country country = Country_Default, TimeZone zone = Local) const;
-

     // comparison (see also functions below for operator versions)
     // ------------------------------------------------------------------------
 
         // returns TRUE if the two moments are strictly identical
     inline bool IsEqualTo(const wxDateTime& datetime) const;
 
     // comparison (see also functions below for operator versions)
     // ------------------------------------------------------------------------
 
         // returns TRUE if the two moments are strictly identical
     inline bool IsEqualTo(const wxDateTime& datetime) const;
 

-        // returns TRUE if the two moments are identical
-    inline bool operator==(const wxDateTime& datetime) const;
-
-        // returns TRUE if the two moments are different
-    inline bool operator!=(const wxDateTime& datetime) const;
-

         // returns TRUE if the date is strictly earlier than the given one
     inline bool IsEarlierThan(const wxDateTime& datetime) const;
 
         // returns TRUE if the date is strictly earlier than the given one
     inline bool IsEarlierThan(const wxDateTime& datetime) const;
 


@@ -642,69 +841,110 @@ public:
         // returns TRUE if the date is in the given range
     inline bool IsBetween(const wxDateTime& t1, const wxDateTime& t2) const;
 
         // returns TRUE if the date is in the given range
     inline bool IsBetween(const wxDateTime& t1, const wxDateTime& t2) const;
 

-    // date operations: for the non-const methods, the return value is this
-    // object itself (see also functions below for operator versions)
+        // do these two objects refer to the same date?
+    inline bool IsSameDate(const wxDateTime& dt) const;
+
+        // do these two objects have the same time?
+    inline bool IsSameTime(const wxDateTime& dt) const;
+
+        // are these two objects equal up to given timespan?
+    inline bool IsEqualUpTo(const wxDateTime& dt, const wxTimeSpan& ts) const;
+
+    // arithmetics with dates (see also below for more operators)

     // ------------------------------------------------------------------------
 
     // ------------------------------------------------------------------------
 

+        // return the sum of the date with a time span (positive or negative)
+    inline wxDateTime Add(const wxTimeSpan& diff) const;

         // add a time span (positive or negative)
     inline wxDateTime& Add(const wxTimeSpan& diff);
         // add a time span (positive or negative)
     inline wxDateTime& operator+=(const wxTimeSpan& diff);
 
         // add a time span (positive or negative)
     inline wxDateTime& Add(const wxTimeSpan& diff);
         // add a time span (positive or negative)
     inline wxDateTime& operator+=(const wxTimeSpan& diff);
 

-        // substract a time span (positive or negative)
-    inline wxDateTime& Substract(const wxTimeSpan& diff);
-        // substract a time span (positive or negative)
+        // return the difference of the date with a time span
+    inline wxDateTime Subtract(const wxTimeSpan& diff) const;
+        // subtract a time span (positive or negative)
+    inline wxDateTime& Subtract(const wxTimeSpan& diff);
+        // subtract a time span (positive or negative)

     inline wxDateTime& operator-=(const wxTimeSpan& diff);
 
     inline wxDateTime& operator-=(const wxTimeSpan& diff);
 

+        // return the sum of the date with a date span
+    inline wxDateTime Add(const wxDateSpan& diff) const;

         // add a date span (positive or negative)
     wxDateTime& Add(const wxDateSpan& diff);
         // add a date span (positive or negative)
     inline wxDateTime& operator+=(const wxDateSpan& diff);
 
         // add a date span (positive or negative)
     wxDateTime& Add(const wxDateSpan& diff);
         // add a date span (positive or negative)
     inline wxDateTime& operator+=(const wxDateSpan& diff);
 

-        // substract a date span (positive or negative)
-    inline wxDateTime& Substract(const wxDateSpan& diff);
-        // substract a date span (positive or negative)
+        // return the difference of the date with a date span
+    inline wxDateTime Subtract(const wxDateSpan& diff) const;
+        // subtract a date span (positive or negative)
+    inline wxDateTime& Subtract(const wxDateSpan& diff);
+        // subtract a date span (positive or negative)

     inline wxDateTime& operator-=(const wxDateSpan& diff);
 
     inline wxDateTime& operator-=(const wxDateSpan& diff);
 

-        // substract a date (may result in positive or negative time span)
-    inline wxTimeSpan Substract(const wxDateTime& datetime) const;
-        // substract a date (may result in positive or negative time span)
-    inline wxTimeSpan operator-(const wxDateTime& datetime) const;
+        // return the difference between two dates
+    inline wxTimeSpan Subtract(const wxDateTime& dt) const;

 
 

-    // conversion to/from text: all conversions from text return TRUE on
-    // success or FALSE if the date is malformed/out of supported range
+    // conversion to/from text: all conversions from text return the pointer to
+    // the next character following the date specification (i.e. the one where
+    // the scan had to stop) or NULL on failure.

     // ------------------------------------------------------------------------
 
         // parse a string in RFC 822 format (found e.g. in mail headers and
         // having the form "Wed, 10 Feb 1999 19:07:07 +0100")
     // ------------------------------------------------------------------------
 
         // parse a string in RFC 822 format (found e.g. in mail headers and
         // having the form "Wed, 10 Feb 1999 19:07:07 +0100")

-    bool ParseRfc822Date(const wxString& date);
-        // parse a date/time in the given format (see strptime(3))
-    bool ParseFormat(const wxString& date, const char *format = "%c");
+    const wxChar *ParseRfc822Date(const wxChar* date);
+        // parse a date/time in the given format (see strptime(3)), fill in
+        // the missing (in the string) fields with the values of dateDef (by
+        // default, they will not change if they had valid values or will
+        // default to Today() otherwise)
+    const wxChar *ParseFormat(const wxChar *date,
+                              const wxChar *format = _T("%c"),
+                              const wxDateTime& dateDef = wxDefaultDateTime);

         // parse a string containing the date/time in "free" format, this
         // function will try to make an educated guess at the string contents
         // parse a string containing the date/time in "free" format, this
         // function will try to make an educated guess at the string contents

-        // (and return FALSE if it fails)
-    bool ParseDateTime(const wxString& date);
+    const wxChar *ParseDateTime(const wxChar *datetime);
+        // parse a string containing the date only in "free" format (less
+        // flexible than ParseDateTime)
+    const wxChar *ParseDate(const wxChar *date);
+        // parse a string containing the time only in "free" format
+    const wxChar *ParseTime(const wxChar *time);

 
         // this function accepts strftime()-like format string (default
         // argument corresponds to the preferred date and time representation
         // for the current locale) and returns the string containing the
         // resulting text representation
 
         // this function accepts strftime()-like format string (default
         // argument corresponds to the preferred date and time representation
         // for the current locale) and returns the string containing the
         // resulting text representation

-    wxString Format(const wxChar *format = _T("%c")) const;
+    wxString Format(const wxChar *format = _T("%c"),
+                    const TimeZone& tz = Local) const;

         // preferred date representation for the current locale
     wxString FormatDate() const { return Format(_T("%x")); }
         // preferred time representation for the current locale
     wxString FormatTime() const { return Format(_T("%X")); }
         // preferred date representation for the current locale
     wxString FormatDate() const { return Format(_T("%x")); }
         // preferred time representation for the current locale
     wxString FormatTime() const { return Format(_T("%X")); }

+        // returns the string representing the date in ISO 8601 format
+        // (YYYY-MM-DD)
+    wxString FormatISODate() const { return Format(_T("%Y-%m-%d")); }
+        // returns the string representing the time in ISO 8601 format
+        // (HH:MM:SS)
+    wxString FormatISOTime() const { return Format(_T("%H:%M:%S")); }

 
     // implementation
     // ------------------------------------------------------------------------
 
 
     // implementation
     // ------------------------------------------------------------------------
 

+        // construct from internal representation
+    wxDateTime(const wxLongLong& time) { m_time = time; }
+

         // get the internal representation
     inline wxLongLong GetValue() const;
 
         // get the internal representation
     inline wxLongLong GetValue() const;
 

-private:

     // a helper function to get the current time_t
     // a helper function to get the current time_t

-    static inline time_t GetTimeNow() { return time((time_t *)NULL); }
+    static time_t GetTimeNow() { return time((time_t *)NULL); }
+
+    // another one to get the current time broken down
+    static struct tm *GetTmNow()
+    {
+        time_t t = GetTimeNow();
+        return localtime(&t);
+    }

 
 

+private:

     // the current country - as it's the same for all program objects (unless
     // it runs on a _really_ big cluster system :-), this is a static member:
     // see SetCountry() and GetCountry()
     // the current country - as it's the same for all program objects (unless
     // it runs on a _really_ big cluster system :-), this is a static member:
     // see SetCountry() and GetCountry()


@@ -713,15 +953,11 @@ private:
     // this constant is used to transform a time_t value to the internal
     // representation, as time_t is in seconds and we use milliseconds it's
     // fixed to 1000
     // this constant is used to transform a time_t value to the internal
     // representation, as time_t is in seconds and we use milliseconds it's
     // fixed to 1000

-    static const unsigned int TIME_T_FACTOR;
-
-    // invalid wxDateTime object - returned by all functions which return
-    // "wxDateTime &" on failure
-    static wxDateTime ms_InvDateTime;
+    static const long TIME_T_FACTOR;

 
     // returns TRUE if we fall in range in which we can use standard ANSI C
     // functions
 
     // returns TRUE if we fall in range in which we can use standard ANSI C
     // functions

-    inline IsInStdRange() const;
+    inline bool IsInStdRange() const;

 
     // the internal representation of the time is the amount of milliseconds
     // elapsed since the origin which is set by convention to the UNIX/C epoch
 
     // the internal representation of the time is the amount of milliseconds
     // elapsed since the origin which is set by convention to the UNIX/C epoch


@@ -731,7 +967,7 @@ private:
 
 // ----------------------------------------------------------------------------
 // This class contains a difference between 2 wxDateTime values, so it makes
 
 // ----------------------------------------------------------------------------
 // This class contains a difference between 2 wxDateTime values, so it makes

-// sense to add it to wxDateTime and it is the result of substraction of 2
+// sense to add it to wxDateTime and it is the result of subtraction of 2

 // objects of that class. See also wxDateSpan.
 // ----------------------------------------------------------------------------
 
 // objects of that class. See also wxDateSpan.
 // ----------------------------------------------------------------------------
 


@@ -741,52 +977,64 @@ public:
     // constructors
     // ------------------------------------------------------------------------
 
     // constructors
     // ------------------------------------------------------------------------
 

+        // return the timespan for the given number of seconds
+    static wxTimeSpan Seconds(long sec) { return wxTimeSpan(0, 0, sec); }
+    static wxTimeSpan Second() { return Seconds(1); }
+
+        // return the timespan for the given number of minutes
+    static wxTimeSpan Minutes(long min) { return wxTimeSpan(0, min, 0 ); }
+    static wxTimeSpan Minute() { return Minutes(1); }
+
+        // return the timespan for the given number of hours
+    static wxTimeSpan Hours(long hours) { return wxTimeSpan(hours, 0, 0); }
+    static wxTimeSpan Hour() { return Hours(1); }
+
+        // return the timespan for the given number of days
+    static wxTimeSpan Days(long days) { return Hours(24 * days); }
+    static wxTimeSpan Day() { return Days(1); }
+
+        // return the timespan for the given number of weeks
+    static wxTimeSpan Weeks(long days) { return Days(7 * days); }
+    static wxTimeSpan Week() { return Weeks(1); }
+

         // default ctor constructs the 0 time span
     wxTimeSpan() { }
 
         // from separate values for each component, date set to 0 (hours are
         // not restricted to 0..24 range, neither are minutes, seconds or
         // milliseconds)
         // default ctor constructs the 0 time span
     wxTimeSpan() { }
 
         // from separate values for each component, date set to 0 (hours are
         // not restricted to 0..24 range, neither are minutes, seconds or
         // milliseconds)

-    wxTimeSpan(int hours,
-               int minutes = 0,
-               int seconds = 0,
-               int milliseconds = 0);
-        // from separate values for each component with explicit date (none of
-        // the parameters isn't restricted to any range)
-    wxTimeSpan(int years,
-               int months,
-               int days,
-               int hours = 0,
-               int minutes = 0,
-               int seconds = 0,
-               int milliseconds = 0);
-
-        // from internal representation
-    wxTimeSpan(wxLongLong diff) : m_diff(diff) { }
+    inline wxTimeSpan(long hours,
+                      long minutes = 0,
+                      long seconds = 0,
+                      long milliseconds = 0);

 
         // default copy ctor is ok
 
         // no dtor
 
 
         // default copy ctor is ok
 
         // no dtor
 

-    // arithmetics with time spans
+    // arithmetics with time spans (see also below for more operators)

     // ------------------------------------------------------------------------
 
     // ------------------------------------------------------------------------
 

+        // return the sum of two timespans
+    inline wxTimeSpan Add(const wxTimeSpan& diff) const;

         // add two timespans together
     inline wxTimeSpan& Add(const wxTimeSpan& diff);
         // add two timespans together
     wxTimeSpan& operator+=(const wxTimeSpan& diff) { return Add(diff); }
 
         // add two timespans together
     inline wxTimeSpan& Add(const wxTimeSpan& diff);
         // add two timespans together
     wxTimeSpan& operator+=(const wxTimeSpan& diff) { return Add(diff); }
 

-        // substract another timespan
-    inline wxTimeSpan& Substract(const wxTimeSpan& diff);
-        // substract another timespan
-    wxTimeSpan& operator-=(const wxTimeSpan& diff) { return Substract(diff); }
+        // return the difference of two timespans
+    inline wxTimeSpan Subtract(const wxTimeSpan& diff) const;
+        // subtract another timespan
+    inline wxTimeSpan& Subtract(const wxTimeSpan& diff);
+        // subtract another timespan
+    wxTimeSpan& operator-=(const wxTimeSpan& diff) { return Subtract(diff); }

 
 

+        // multiply timespan by a scalar
+    inline wxTimeSpan Multiply(int n) const;

         // multiply timespan by a scalar
     inline wxTimeSpan& Multiply(int n);
         // multiply timespan by a scalar
     wxTimeSpan& operator*=(int n) { return Multiply(n); }
         // multiply timespan by a scalar
     inline wxTimeSpan& Multiply(int n);
         // multiply timespan by a scalar
     wxTimeSpan& operator*=(int n) { return Multiply(n); }

-        // multiply timespan by a scalar
-    inline wxTimeSpan operator*(int n) const;

 
         // return this timespan with inversed sign
     wxTimeSpan Negate() const { return wxTimeSpan(-GetValue()); }
 
         // return this timespan with inversed sign
     wxTimeSpan Negate() const { return wxTimeSpan(-GetValue()); }


@@ -827,16 +1075,9 @@ public:
         // timespans are equal in absolute value.
     bool IsShorterThan(const wxTimeSpan& t) const { return !IsLongerThan(t); }
 
         // timespans are equal in absolute value.
     bool IsShorterThan(const wxTimeSpan& t) const { return !IsLongerThan(t); }
 

-    // breaking into years, ..., days, ..., seconds: all these functions
-    // behave like GetYears() which returns 1 for the timespan of 1 year and 1
-    // day, but 0 (and not -1) for the negative timespan of 1 year without 1
-    // day. IOW, (ts - wxTimeSpan(ts.GetYears())).GetYears() is always 0.
+    // breaking into days, hours, minutes and seconds

     // ------------------------------------------------------------------------
 
     // ------------------------------------------------------------------------
 

-        // get the max number of years in this timespan
-    inline int GetYears() const;
-        // get the max number of months in this timespan
-    inline int GetMonths() const;

         // get the max number of weeks in this timespan
     inline int GetWeeks() const;
         // get the max number of days in this timespan
         // get the max number of weeks in this timespan
     inline int GetWeeks() const;
         // get the max number of days in this timespan


@@ -846,7 +1087,7 @@ public:
         // get the max number of minutes in this timespan
     inline int GetMinutes() const;
         // get the max number of seconds in this timespan
         // get the max number of minutes in this timespan
     inline int GetMinutes() const;
         // get the max number of seconds in this timespan

-    inline int GetSeconds() const;
+    inline wxLongLong GetSeconds() const;

         // get the number of milliseconds in this timespan
     wxLongLong GetMilliseconds() const { return m_diff; }
 
         // get the number of milliseconds in this timespan
     wxLongLong GetMilliseconds() const { return m_diff; }
 


@@ -859,15 +1100,14 @@ public:
         // resulting text representation. Notice that only some of format
         // specifiers valid for wxDateTime are valid for wxTimeSpan: hours,
         // minutes and seconds make sense, but not "PM/AM" string for example.
         // resulting text representation. Notice that only some of format
         // specifiers valid for wxDateTime are valid for wxTimeSpan: hours,
         // minutes and seconds make sense, but not "PM/AM" string for example.

-    wxString Format(const char *format = "%c") const;
-        // preferred date representation for the current locale
-    wxString FormatDate() const { return Format("%x"); }
-        // preferred time representation for the current locale
-    wxString FormatTime() const { return Format("%X"); }
+    wxString Format(const wxChar *format = _T("%H:%M:%S")) const;

 
     // implementation
     // ------------------------------------------------------------------------
 
 
     // implementation
     // ------------------------------------------------------------------------
 

+        // construct from internal representation
+    wxTimeSpan(const wxLongLong& diff) { m_diff = diff; }
+

         // get the internal representation
     wxLongLong GetValue() const { return m_diff; }
 
         // get the internal representation
     wxLongLong GetValue() const { return m_diff; }
 


@@ -884,7 +1124,12 @@ private:
 // one month to Feb, 15 - we want to get Mar, 15, of course).
 //
 // When adding a month to the date, all lesser components (days, hours, ...)
 // one month to Feb, 15 - we want to get Mar, 15, of course).
 //
 // When adding a month to the date, all lesser components (days, hours, ...)

-// won't be changed.
+// won't be changed unless the resulting date would be invalid: for example,
+// Jan 31 + 1 month will be Feb 28, not (non existing) Feb 31.
+//
+// Because of this feature, adding and subtracting back again the same
+// wxDateSpan will *not*, in general give back the original date: Feb 28 - 1
+// month will be Jan 28, not Jan 31!

 //
 // wxDateSpan can be either positive or negative. They may be
 // multiplied by scalars which multiply all deltas by the scalar: i.e. 2*(1
 //
 // wxDateSpan can be either positive or negative. They may be
 // multiplied by scalars which multiply all deltas by the scalar: i.e. 2*(1


@@ -907,7 +1152,29 @@ public:
     // ------------------------------------------------------------------------
 
         // this many years/months/weeks/days
     // ------------------------------------------------------------------------
 
         // this many years/months/weeks/days

-    wxDateSpan(int years, int months, int weeks, int days);
+    wxDateSpan(int years = 0, int months = 0, int weeks = 0, int days = 0)
+    {
+        m_years = years;
+        m_months = months;
+        m_weeks = weeks;
+        m_days = days;
+    }
+
+        // get an object for the given number of days
+    static wxDateSpan Days(int days) { return wxDateSpan(0, 0, 0, days); }
+    static wxDateSpan Day() { return Days(1); }
+
+        // get an object for the given number of weeks
+    static wxDateSpan Weeks(int weeks) { return wxDateSpan(0, 0, weeks, 0); }
+    static wxDateSpan Week() { return Weeks(1); }
+
+        // get an object for the given number of months
+    static wxDateSpan Months(int mon) { return wxDateSpan(0, mon, 0, 0); }
+    static wxDateSpan Month() { return Months(1); }
+
+        // get an object for the given number of years
+    static wxDateSpan Years(int years) { return wxDateSpan(years, 0, 0, 0); }
+    static wxDateSpan Year() { return Years(1); }

 
         // default copy ctor is ok
 
 
         // default copy ctor is ok
 


@@ -936,17 +1203,21 @@ public:
         // returns 7*GetWeeks() + GetDays()
     int GetTotalDays() const { return 7*m_weeks + m_days; }
 
         // returns 7*GetWeeks() + GetDays()
     int GetTotalDays() const { return 7*m_weeks + m_days; }
 

-    // arithmetics
+    // arithmetics with date spans (see also below for more operators)

     // ------------------------------------------------------------------------
 
     // ------------------------------------------------------------------------
 

+        // return sum of two date spans
+    inline wxDateSpan Add(const wxDateSpan& other) const;

         // add another wxDateSpan to us
     inline wxDateSpan& Add(const wxDateSpan& other);
         // add another wxDateSpan to us
     inline wxDateSpan& operator+=(const wxDateSpan& other);
 
         // add another wxDateSpan to us
     inline wxDateSpan& Add(const wxDateSpan& other);
         // add another wxDateSpan to us
     inline wxDateSpan& operator+=(const wxDateSpan& other);
 

-        // substract another wxDateSpan from us
-    inline wxDateSpan& Substract(const wxDateSpan& other);
-        // substract another wxDateSpan from us
+        // return difference of two date spans
+    inline wxDateSpan Subtract(const wxDateSpan& other) const;
+        // subtract another wxDateSpan from us
+    inline wxDateSpan& Subtract(const wxDateSpan& other);
+        // subtract another wxDateSpan from us

     inline wxDateSpan& operator-=(const wxDateSpan& other);
 
         // return a copy of this time span with changed sign
     inline wxDateSpan& operator-=(const wxDateSpan& other);
 
         // return a copy of this time span with changed sign


@@ -956,8 +1227,12 @@ public:
         // inverse the sign of this timespan
     wxDateSpan& operator-() { return Neg(); }
 
         // inverse the sign of this timespan
     wxDateSpan& operator-() { return Neg(); }
 

+        // return the date span proportional to this one with given factor
+    inline wxDateSpan Multiply(int factor) const;

         // multiply all components by a (signed) number
         // multiply all components by a (signed) number

-    inline wxDateSpan& operator*=(int factor);
+    inline wxDateSpan& Multiply(int factor);
+        // multiply all components by a (signed) number
+    inline wxDateSpan& operator*=(int factor) { return Multiply(factor); }

 
 private:
     int m_years,
 
 private:
     int m_years,


@@ -966,437 +1241,320 @@ private:
         m_days;
 };
 
         m_days;
 };
 

-WXDLLEXPORT_DATA(extern wxDateSpan) wxYear;
-WXDLLEXPORT_DATA(extern wxDateSpan) wxMonth;
-WXDLLEXPORT_DATA(extern wxDateSpan) wxWeek;
-WXDLLEXPORT_DATA(extern wxDateSpan) wxDay;
-
-// ============================================================================
-// binary operators
-// ============================================================================
-

 // ----------------------------------------------------------------------------
 // ----------------------------------------------------------------------------

-// wxDateTime operators
+// wxDateTimeArray: array of dates.

 // ----------------------------------------------------------------------------
 
 // ----------------------------------------------------------------------------
 

-inline bool WXDLLEXPORT operator<(const wxDateTime &t1, const wxDateTime &t2)
-{
-    wxASSERT_MSG( t1.IsValid() && t2.IsValid(), "invalid wxDateTime" );
-
-    return t1.GetValue() < t2.GetValue();
-}
-
-inline bool WXDLLEXPORT operator<=(const wxDateTime &t1, const wxDateTime &t2)
-{
-    wxASSERT_MSG( t1.IsValid() && t2.IsValid(), "invalid wxDateTime" );
-
-    return t1.GetValue() <= t2.GetValue();
-}
-
-inline bool WXDLLEXPORT operator>(const wxDateTime &t1, const wxDateTime &t2)
-{
-    wxASSERT_MSG( t1.IsValid() && t2.IsValid(), "invalid wxDateTime" );
-
-    return t1.GetValue() > t2.GetValue();
-}
-
-inline bool WXDLLEXPORT operator>=(const wxDateTime &t1, const wxDateTime &t2)
-{
-    wxASSERT_MSG( t1.IsValid() && t2.IsValid(), "invalid wxDateTime" );
-
-    return t1.GetValue() >= t2.GetValue();
-}
-
-inline bool WXDLLEXPORT operator==(const wxDateTime &t1, const wxDateTime &t2)
-{
-    wxASSERT_MSG( t1.IsValid() && t2.IsValid(), "invalid wxDateTime" );
+#include "wx/dynarray.h"

 
 

-    return t1.GetValue() == t2.GetValue();
-}
-
-inline bool WXDLLEXPORT operator!=(const wxDateTime &t1, const wxDateTime &t2)
-{
-    wxASSERT_MSG( t1.IsValid() && t2.IsValid(), "invalid wxDateTime" );
-
-    return t1.GetValue() != t2.GetValue();
-}
-
-inline wxTimeSpan WXDLLEXPORT operator-(const wxDateTime &t1,
-                                        const wxDateTime &t2)
-{
-    wxASSERT_MSG( t1.IsValid() && t2.IsValid(), "invalid wxDateTime" );
-
-    return wxTimeSpan(t1.GetValue() - t2.GetValue());
-}
+WX_DECLARE_EXPORTED_OBJARRAY(wxDateTime, wxDateTimeArray);

 
 // ----------------------------------------------------------------------------
 
 // ----------------------------------------------------------------------------

-// wxTimeSpan operators
+// wxDateTimeHolidayAuthority: an object of this class will decide whether a
+// given date is a holiday and is used by all functions working with "work
+// days".
+//
+// NB: the base class is an ABC, derived classes must implement the pure
+//     virtual methods to work with the holidays they correspond to.

 // ----------------------------------------------------------------------------
 
 // ----------------------------------------------------------------------------
 

-inline wxTimeSpan WXDLLEXPORT operator+(const wxTimeSpan& ts1,
-                                        const wxTimeSpan& ts2)
-{
-    return wxTimeSpan(ts1.GetValue() + ts2.GetValue());
-}
-
-inline wxTimeSpan WXDLLEXPORT operator-(const wxTimeSpan& ts1,
-                                        const wxTimeSpan& ts2)
-{
-    return wxTimeSpan(ts1.GetValue() - ts2.GetValue());
-}
-
-inline bool WXDLLEXPORT operator<(const wxTimeSpan &t1, const wxTimeSpan &t2)
-{
-    return t1.GetValue() < t2.GetValue();
-}
+class WXDLLEXPORT wxDateTimeHolidayAuthority;
+WX_DEFINE_EXPORTED_ARRAY(wxDateTimeHolidayAuthority *, wxHolidayAuthoritiesArray);

 
 

-inline bool WXDLLEXPORT operator<=(const wxTimeSpan &t1, const wxTimeSpan &t2)
+class wxDateTimeHolidaysModule;
+class WXDLLEXPORT wxDateTimeHolidayAuthority

 {
 {

-    return t1.GetValue() <= t2.GetValue();
-}
+friend class wxDateTimeHolidaysModule;
+public:
+    // returns TRUE if the given date is a holiday
+    static bool IsHoliday(const wxDateTime& dt);
+
+    // fills the provided array with all holidays in the given range, returns
+    // the number of them
+    static size_t GetHolidaysInRange(const wxDateTime& dtStart,
+                                     const wxDateTime& dtEnd,
+                                     wxDateTimeArray& holidays);
+
+    // clear the list of holiday authorities
+    static void ClearAllAuthorities();
+
+    // add a new holiday authority (the pointer will be deleted by
+    // wxDateTimeHolidayAuthority)
+    static void AddAuthority(wxDateTimeHolidayAuthority *auth);
+
+protected:
+    // this function is called to determine whether a given day is a holiday
+    virtual bool DoIsHoliday(const wxDateTime& dt) const = 0;
+
+    // this function should fill the array with all holidays between the two
+    // given dates - it is implemented in the base class, but in a very
+    // inefficient way (it just iterates over all days and uses IsHoliday() for
+    // each of them), so it must be overridden in the derived class where the
+    // base class version may be explicitly used if needed
+    //
+    // returns the number of holidays in the given range and fills holidays
+    // array
+    virtual size_t DoGetHolidaysInRange(const wxDateTime& dtStart,
+                                        const wxDateTime& dtEnd,
+                                        wxDateTimeArray& holidays) const = 0;

 
 

-inline bool WXDLLEXPORT operator>(const wxTimeSpan &t1, const wxTimeSpan &t2)
-{
-    return t1.GetValue() > t2.GetValue();
-}
+private:
+    // all holiday authorities
+    static wxHolidayAuthoritiesArray ms_authorities;
+};

 
 

-inline bool WXDLLEXPORT operator>=(const wxTimeSpan &t1, const wxTimeSpan &t2)
+// the holidays for this class are all Saturdays and Sundays
+class WXDLLEXPORT wxDateTimeWorkDays : public wxDateTimeHolidayAuthority

 {
 {

-    return t1.GetValue() >= t2.GetValue();
-}
+protected:
+    virtual bool DoIsHoliday(const wxDateTime& dt) const;
+    virtual size_t DoGetHolidaysInRange(const wxDateTime& dtStart,
+                                        const wxDateTime& dtEnd,
+                                        wxDateTimeArray& holidays) const;
+};

 
 

-inline bool WXDLLEXPORT operator==(const wxTimeSpan &t1, const wxTimeSpan &t2)
-{
-    return t1.GetValue() == t2.GetValue();
-}
+// ============================================================================
+// inline functions implementation
+// ============================================================================

 
 

-inline bool WXDLLEXPORT operator!=(const wxTimeSpan &t1, const wxTimeSpan &t2)
-{
-    return t1.GetValue() != t2.GetValue();
-}
+// don't include inline functions definitions when we're included from anything
+// else than datetime.cpp in debug builds: this minimizes rebuilds if we change
+// some inline function and the performance doesn't matter in the debug builds.

 
 

-// ----------------------------------------------------------------------------
-// wxDateSpan
-// ----------------------------------------------------------------------------
+#if !defined(__WXDEBUG__) || defined(wxDEFINE_TIME_CONSTANTS)
+    #define INCLUDED_FROM_WX_DATETIME_H
+        #include "wx/datetime.inl"
+    #undef INCLUDED_FROM_WX_DATETIME_H
+#endif

 
 

-inline WXDLLEXPORT wxDateSpan operator+(const wxDateSpan& rt1,
-                                        const wxDateSpan& rt2)
-{
-    return wxDateSpan(rt1.GetYears() + rt2.GetYears(),
-                      rt1.GetMonths() + rt2.GetMonths(),
-                      rt1.GetWeeks() + rt2.GetWeeks(),
-                      rt1.GetDays() + rt2.GetDays());
-}
+// if we defined it to be empty above, restore it now
+#undef inline

 
 // ============================================================================
 
 // ============================================================================

-// inline functions implementation
+// binary operators

 // ============================================================================
 
 // ----------------------------------------------------------------------------
 // ============================================================================
 
 // ----------------------------------------------------------------------------

-// wxDateTime statics
-// ----------------------------------------------------------------------------
-
-/* static */
-wxDateTime::Country wxDateTime::GetCountry()
-{
-    return ms_country;
-}
-
-// ----------------------------------------------------------------------------
-// wxDateTime construction
+// wxDateTime operators

 // ----------------------------------------------------------------------------
 
 // ----------------------------------------------------------------------------
 

-// only define this once, when included from datetime.cpp
-#ifdef wxDEFINE_TIME_CONSTANTS
-    const unsigned int wxDateTime::TIME_T_FACTOR = 1000;
-#endif // wxDEFINE_TIME_CONSTANTS
+// arithmetics
+// -----------

 
 

-wxDateTime::IsInStdRange() const
-{
-    return m_time >= 0l && (m_time / (long)TIME_T_FACTOR) < LONG_MAX;
-}
+// no need to check for validity - the member functions we call will do it

 
 

-/* static */
-wxDateTime wxDateTime::Now()
+inline wxDateTime WXDLLEXPORT operator+(const wxDateTime& dt,
+                                        const wxTimeSpan& ts)

 {
 {

-    return wxDateTime(GetTimeNow());
+    return dt.Add(ts);

 }
 
 }
 

-wxDateTime& wxDateTime::Set(time_t timet)
+inline wxDateTime WXDLLEXPORT operator-(const wxDateTime& dt,
+                                        const wxTimeSpan& ts)

 {
 {

-    m_time = timet * TIME_T_FACTOR;
-
-    return *this;
+    return dt.Subtract(ts);

 }
 
 }
 

-wxDateTime& wxDateTime::SetToCurrent()
+inline wxDateTime WXDLLEXPORT operator+(const wxDateTime& dt,
+                                        const wxDateSpan& ds)

 {
 {

-    return Set(GetTimeNow());
+    return dt.Add(ds);

 }
 
 }
 

-wxDateTime::wxDateTime(time_t timet)
+inline wxDateTime WXDLLEXPORT operator-(const wxDateTime& dt,
+                                        const wxDateSpan& ds)

 {
 {

-    Set(timet);
+    return dt.Subtract(ds);

 }
 
 }
 

-wxDateTime::wxDateTime(const struct tm& tm)
+inline wxTimeSpan WXDLLEXPORT operator-(const wxDateTime& dt1,
+                                        const wxDateTime& dt2)

 {
 {

-    Set(tm);
+    return dt1.Subtract(dt2);

 }
 
 }
 

-wxDateTime::wxDateTime(const Tm& tm)
-{
-    Set(tm);
-}
-
-wxDateTime& wxDateTime::Set(const Tm& tm)
-{
-    wxASSERT_MSG( tm.IsValid(), _T("invalid broken down date/time") );
+// comparison
+// ----------

 
 

-    return Set(tm.mday, (Month)tm.mon, tm.year, tm.hour, tm.min, tm.sec);
-}
-
-wxDateTime::wxDateTime(wxDateTime_t hour,
-                       wxDateTime_t minute,
-                       wxDateTime_t second,
-                       wxDateTime_t millisec)
+inline bool WXDLLEXPORT operator<(const wxDateTime& t1, const wxDateTime& t2)

 {
 {

-    Set(hour, minute, second, millisec);
-}
+    wxASSERT_MSG( t1.IsValid() && t2.IsValid(), _T("invalid wxDateTime") );

 
 

-wxDateTime::wxDateTime(wxDateTime_t day,
-                       Month        month,
-                       int          year,
-                       wxDateTime_t hour,
-                       wxDateTime_t minute,
-                       wxDateTime_t second,
-                       wxDateTime_t millisec)
-{
-    Set(day, month, year, hour, minute, second, millisec);
+    return t1.GetValue() < t2.GetValue();

 }
 
 }
 

-// ----------------------------------------------------------------------------
-// wxDateTime accessors
-// ----------------------------------------------------------------------------
-
-wxLongLong wxDateTime::GetValue() const
+inline bool WXDLLEXPORT operator<=(const wxDateTime& t1, const wxDateTime& t2)

 {
 {

-    wxASSERT_MSG( IsValid(), "invalid wxDateTime");
+    wxASSERT_MSG( t1.IsValid() && t2.IsValid(), _T("invalid wxDateTime") );

 
 

-    return m_time;
+    return t1.GetValue() <= t2.GetValue();

 }
 
 }
 

-time_t wxDateTime::GetTicks() const
+inline bool WXDLLEXPORT operator>(const wxDateTime& t1, const wxDateTime& t2)

 {
 {

-    wxASSERT_MSG( IsValid(), "invalid wxDateTime");
-    if ( !IsInStdRange() )
-    {
-        return (time_t)-1;
-    }
-
-    return (time_t)((m_time / (long)TIME_T_FACTOR).GetLo());
-}
+    wxASSERT_MSG( t1.IsValid() && t2.IsValid(), _T("invalid wxDateTime") );

 
 

-bool wxDateTime::SetToLastWeekDay(WeekDay weekday,
-                                  wxDateTime_t month,
-                                  int year)
-{
-    SetToWeekDay(weekday, -1, month, year);
+    return t1.GetValue() > t2.GetValue();

 }
 
 }
 

-// ----------------------------------------------------------------------------
-// wxDateTime comparison
-// ----------------------------------------------------------------------------
-
-bool wxDateTime::IsEqualTo(const wxDateTime& datetime) const
+inline bool WXDLLEXPORT operator>=(const wxDateTime& t1, const wxDateTime& t2)

 {
 {

-    wxASSERT_MSG( IsValid() && datetime.IsValid(), "invalid wxDateTime");
+    wxASSERT_MSG( t1.IsValid() && t2.IsValid(), _T("invalid wxDateTime") );

 
 

-    return m_time == datetime.m_time;
+    return t1.GetValue() >= t2.GetValue();

 }
 
 }
 

-bool wxDateTime::operator==(const wxDateTime& datetime) const
+inline bool WXDLLEXPORT operator==(const wxDateTime& t1, const wxDateTime& t2)

 {
 {

-    return IsEqualTo(datetime);
-}
+    wxASSERT_MSG( t1.IsValid() && t2.IsValid(), _T("invalid wxDateTime") );

 
 

-bool wxDateTime::operator!=(const wxDateTime& datetime) const
-{
-    return !IsEqualTo(datetime);
+    return t1.GetValue() == t2.GetValue();

 }
 
 }
 

-bool wxDateTime::IsEarlierThan(const wxDateTime& datetime) const
+inline bool WXDLLEXPORT operator!=(const wxDateTime& t1, const wxDateTime& t2)

 {
 {

-    wxASSERT_MSG( IsValid() && datetime.IsValid(), "invalid wxDateTime");
+    wxASSERT_MSG( t1.IsValid() && t2.IsValid(), _T("invalid wxDateTime") );

 
 

-    return m_time < datetime.m_time;
+    return t1.GetValue() != t2.GetValue();

 }
 
 }
 

-bool wxDateTime::IsLaterThan(const wxDateTime& datetime) const
-{
-    wxASSERT_MSG( IsValid() && datetime.IsValid(), "invalid wxDateTime");
+// ----------------------------------------------------------------------------
+// wxTimeSpan operators
+// ----------------------------------------------------------------------------

 
 

-    return m_time > datetime.m_time;
-}
+// arithmetics
+// -----------

 
 

-bool wxDateTime::IsStrictlyBetween(const wxDateTime& t1,
-                                   const wxDateTime& t2) const
+inline wxTimeSpan WXDLLEXPORT operator+(const wxTimeSpan& ts1,
+                                        const wxTimeSpan& ts2)

 {
 {

-    // no need for assert, will be checked by the functions we call
-    return IsLaterThan(t1) && IsEarlierThan(t2);
+    return wxTimeSpan(ts1.GetValue() + ts2.GetValue());

 }
 
 }
 

-bool wxDateTime::IsBetween(const wxDateTime& t1, const wxDateTime& t2) const
+inline wxTimeSpan WXDLLEXPORT operator-(const wxTimeSpan& ts1,
+                                        const wxTimeSpan& ts2)

 {
 {

-    // no need for assert, will be checked by the functions we call
-    return IsEqualTo(t1) || IsEqualTo(t2) || IsStrictlyBetween(t1, t2);
+    return wxTimeSpan(ts1.GetValue() - ts2.GetValue());

 }
 
 }
 

-// ----------------------------------------------------------------------------
-// wxDateTime arithmetics
-// ----------------------------------------------------------------------------
-
-wxDateTime& wxDateTime::Add(const wxTimeSpan& diff)
+inline wxTimeSpan WXDLLEXPORT operator*(const wxTimeSpan& ts, int n)

 {
 {

-    wxASSERT_MSG( IsValid(), "invalid wxDateTime");
-
-    m_time += diff.GetValue();
-
-    return *this;
+    return wxTimeSpan(ts).Multiply(n);

 }
 
 }
 

-wxDateTime& wxDateTime::operator+=(const wxTimeSpan& diff)
+inline wxTimeSpan WXDLLEXPORT operator*(int n, const wxTimeSpan& ts)

 {
 {

-    return Add(diff);
+    return wxTimeSpan(ts).Multiply(n);

 }
 
 }
 

-wxDateTime& wxDateTime::Substract(const wxTimeSpan& diff)
-{
-    wxASSERT_MSG( IsValid(), "invalid wxDateTime");
-
-    m_time -= diff.GetValue();
-
-    return *this;
-}
+// comparison
+// ----------

 
 

-wxDateTime& wxDateTime::operator-=(const wxTimeSpan& diff)
+inline bool WXDLLEXPORT operator<(const wxTimeSpan &t1, const wxTimeSpan &t2)

 {
 {

-    return Substract(diff);
+    return t1.GetValue() < t2.GetValue();

 }
 
 }
 

-wxTimeSpan wxDateTime::Substract(const wxDateTime& datetime) const
+inline bool WXDLLEXPORT operator<=(const wxTimeSpan &t1, const wxTimeSpan &t2)

 {
 {

-    wxASSERT_MSG( IsValid() && datetime.IsValid(), "invalid wxDateTime");
-
-    return wxTimeSpan(datetime.GetValue() - GetValue());
+    return t1.GetValue() <= t2.GetValue();

 }
 
 }
 

-wxTimeSpan wxDateTime::operator-(const wxDateTime& datetime) const
+inline bool WXDLLEXPORT operator>(const wxTimeSpan &t1, const wxTimeSpan &t2)

 {
 {

-    return Substract(datetime);
+    return t1.GetValue() > t2.GetValue();

 }
 
 }
 

-wxDateTime& wxDateTime::Substract(const wxDateSpan& diff)
+inline bool WXDLLEXPORT operator>=(const wxTimeSpan &t1, const wxTimeSpan &t2)

 {
 {

-    return Add(diff.Negate());
+    return t1.GetValue() >= t2.GetValue();

 }
 
 }
 

-wxDateTime& wxDateTime::operator-=(const wxDateSpan& diff)
+inline bool WXDLLEXPORT operator==(const wxTimeSpan &t1, const wxTimeSpan &t2)

 {
 {

-    return Substract(diff);
+    return t1.GetValue() == t2.GetValue();

 }
 
 }
 

-wxDateTime& wxDateTime::operator+=(const wxDateSpan& diff)
+inline bool WXDLLEXPORT operator!=(const wxTimeSpan &t1, const wxTimeSpan &t2)

 {
 {

-    return Add(diff);
+    return t1.GetValue() != t2.GetValue();

 }
 
 // ----------------------------------------------------------------------------
 }
 
 // ----------------------------------------------------------------------------

-// wxTimeSpan
+// wxDateSpan

 // ----------------------------------------------------------------------------
 
 // ----------------------------------------------------------------------------
 

-wxTimeSpan& wxTimeSpan::Add(const wxTimeSpan& diff)
-{
-    m_diff += diff.GetValue();
-
-    return *this;
-}
+// arithmetics
+// -----------

 
 

-wxTimeSpan& wxTimeSpan::Substract(const wxTimeSpan& diff)
+inline WXDLLEXPORT wxDateSpan operator+(const wxDateSpan& ds1,
+                                        const wxDateSpan& ds2)

 {
 {

-    m_diff -= diff.GetValue();
-
-    return *this;
+    return wxDateSpan(ds1.GetYears() + ds2.GetYears(),
+                      ds1.GetMonths() + ds2.GetMonths(),
+                      ds1.GetWeeks() + ds2.GetWeeks(),
+                      ds1.GetDays() + ds2.GetDays());

 }
 
 }
 

-wxTimeSpan& wxTimeSpan::Multiply(int n)
+inline WXDLLEXPORT wxDateSpan operator-(const wxDateSpan& ds1,
+                                        const wxDateSpan& ds2)

 {
 {

-    m_diff *= n;
-
-    return *this;
+    return wxDateSpan(ds1.GetYears() - ds2.GetYears(),
+                      ds1.GetMonths() - ds2.GetMonths(),
+                      ds1.GetWeeks() - ds2.GetWeeks(),
+                      ds1.GetDays() - ds2.GetDays());

 }
 
 }
 

-wxTimeSpan wxTimeSpan::operator*(int n) const
+inline WXDLLEXPORT wxDateSpan operator*(const wxDateSpan& ds, int n)

 {
 {

-    wxTimeSpan result(*this);
-    result.Multiply(n);
-
-    return result;
+    return wxDateSpan(ds).Multiply(n);

 }
 
 }
 

-wxTimeSpan wxTimeSpan::Abs() const
+inline WXDLLEXPORT wxDateSpan operator*(int n, const wxDateSpan& ds)

 {
 {

-    return wxTimeSpan(GetValue().Abs());
+    return wxDateSpan(ds).Multiply(n);

 }
 
 }
 

-bool wxTimeSpan::IsEqualTo(const wxTimeSpan& ts) const
-{
-    return GetValue() == ts.GetValue();
-}
-
-bool wxTimeSpan::IsLongerThan(const wxTimeSpan& ts) const
-{
-    return Abs() > ts.Abs();
-}
+// ============================================================================
+// other helper functions
+// ============================================================================

 
 // ----------------------------------------------------------------------------
 
 // ----------------------------------------------------------------------------

-// wxDateSpan
+// iteration helpers: can be used to write a for loop over enum variable like
+// this:
+//  for ( m = wxDateTime::Jan; m < wxDateTime::Inv_Month; wxNextMonth(m) )

 // ----------------------------------------------------------------------------
 
 // ----------------------------------------------------------------------------
 

-wxDateSpan&
-wxDateSpan::operator+=(const wxDateSpan& other)
+inline WXDLLEXPORT void wxNextMonth(wxDateTime::Month& m)

 {
 {

-    m_years += other.m_years;
-    m_months += other.m_months;
-    m_weeks += other.m_weeks;
-    m_days += other.m_days;
+    wxASSERT_MSG( m < wxDateTime::Inv_Month, _T("invalid month") );

 
 

-    return *this;
+    // no wrapping or the for loop above would never end!
+    m = (wxDateTime::Month)(m + 1);

 }
 
 }
 

-wxDateSpan& wxDateSpan::operator*=(int factor)
+inline WXDLLEXPORT void wxPrevMonth(wxDateTime::Month& m)

 {
 {

-    m_years *= m_years;
-    m_months *= m_months;
-    m_weeks *= m_weeks;
-    m_days *= m_days;
+    wxASSERT_MSG( m < wxDateTime::Inv_Month, _T("invalid month") );

 
 

-    return *this;
+    m = m == wxDateTime::Jan ? wxDateTime::Inv_Month
+                             : (wxDateTime::Month)(m - 1);

 }
 
 }
 

-wxDateSpan wxDateSpan::Negate() const
+inline WXDLLEXPORT void wxNextWDay(wxDateTime::WeekDay& wd)

 {
 {

-    return wxDateSpan(-m_years, -m_months, -m_weeks, -m_days);
+    wxASSERT_MSG( wd < wxDateTime::Inv_WeekDay, _T("invalid week day") );
+
+    // no wrapping or the for loop above would never end!
+    wd = (wxDateTime::WeekDay)(wd + 1);

 }
 
 }
 

-wxDateSpan& wxDateSpan::Neg()
+inline WXDLLEXPORT void wxPrevWDay(wxDateTime::WeekDay& wd)

 {
 {

-    m_years = -m_years;
-    m_months = -m_months;
-    m_weeks = -m_weeks;
-    m_days = -m_days;
+    wxASSERT_MSG( wd < wxDateTime::Inv_WeekDay, _T("invalid week day") );

 
 

-    return *this;
+    wd = wd == wxDateTime::Sun ? wxDateTime::Inv_WeekDay
+                               : (wxDateTime::WeekDay)(wd - 1);

 }
 
 }
 

-#endif // _WX_TIME_H
+#endif // _WX_DATETIME_H