while ( monDiff + mon > MONTHS_IN_YEAR )
{
year++;
+
+ monDiff -= MONTHS_IN_YEAR;
}
mon = (wxDateTime::Month)(mon + monDiff);
return year > 0 ? year / 100 : year / 100 - 1;
}
-/* static */
-void wxDateTime::SetCountry(wxDateTime::Country country)
-{
- ms_country = country;
-}
-
/* static */
int wxDateTime::ConvertYearToBC(int year)
{
return CallStrftime(abbr ? _T("%a") : _T("%A"), &tm);
}
+// ----------------------------------------------------------------------------
+// Country stuff: date calculations depend on the country (DST, work days,
+// ...), so we need to know which rules to follow.
+// ----------------------------------------------------------------------------
+
+/* static */
+wxDateTime::Country wxDateTime::GetCountry()
+{
+ if ( ms_country == Country_Unknown )
+ {
+ // try to guess from the time zone name
+ time_t t = time(NULL);
+ struct tm *tm = localtime(&t);
+
+ wxString tz = CallStrftime(_T("%Z"), tm);
+ if ( tz == _T("WET") || tz == _T("WEST") )
+ {
+ ms_country = UK;
+ }
+ else if ( tz == _T("CET") || tz == _T("CEST") )
+ {
+ ms_country = Country_EEC;
+ }
+ else if ( tz == _T("MSK") || tz == _T("MSD") )
+ {
+ ms_country = Russia;
+ }
+ else if ( tz == _T("AST") || tz == _T("ADT") ||
+ tz == _T("EST") || tz == _T("EDT") ||
+ tz == _T("CST") || tz == _T("CDT") ||
+ tz == _T("MST") || tz == _T("MDT") ||
+ tz == _T("PST") || tz == _T("PDT") )
+ {
+ ms_country = USA;
+ }
+ else
+ {
+ // well, choose a default one
+ ms_country = USA;
+ }
+ }
+
+ return ms_country;
+}
+
+/* static */
+void wxDateTime::SetCountry(wxDateTime::Country country)
+{
+ ms_country = country;
+}
+
+/* static */
+bool wxDateTime::IsWestEuropeanCountry(Country country)
+{
+ if ( country == Country_Default )
+ {
+ country = GetCountry();
+ }
+
+ return (Country_WesternEurope_Start <= country) &&
+ (country <= Country_WesternEurope_End);
+}
+
+// ----------------------------------------------------------------------------
+// DST calculations: we use 3 different rules for the West European countries,
+// USA and for the rest of the world. This is undoubtedly false for many
+// countries, but I lack the necessary info (and the time to gather it),
+// please add the other rules here!
+// ----------------------------------------------------------------------------
+
+/* static */
+bool wxDateTime::IsDSTApplicable(int year, Country country)
+{
+ if ( year == Inv_Year )
+ {
+ // take the current year if none given
+ year = GetCurrentYear();
+ }
+
+ if ( country == Country_Default )
+ {
+ country = GetCountry();
+ }
+
+ switch ( country )
+ {
+ case USA:
+ case UK:
+ // DST was first observed in the US and UK during WWI, reused
+ // during WWII and used again since 1966
+ return year >= 1966 ||
+ (year >= 1942 && year <= 1945) ||
+ (year == 1918 || year == 1919);
+
+ default:
+ // assume that it started after WWII
+ return year > 1950;
+ }
+}
+
+/* static */
+wxDateTime wxDateTime::GetBeginDST(int year, Country country)
+{
+ if ( year == Inv_Year )
+ {
+ // take the current year if none given
+ year = GetCurrentYear();
+ }
+
+ if ( country == Country_Default )
+ {
+ country = GetCountry();
+ }
+
+ if ( !IsDSTApplicable(year, country) )
+ {
+ return ms_InvDateTime;
+ }
+
+ wxDateTime dt;
+
+ if ( IsWestEuropeanCountry(country) || (country == Russia) )
+ {
+ // DST begins at 1 a.m. GMT on the last Sunday of March
+ if ( !dt.SetToLastWeekDay(Sun, Mar, year) )
+ {
+ // weird...
+ wxFAIL_MSG( _T("no last Sunday in March?") );
+ }
+
+ dt += wxTimeSpan::Hours(1);
+
+ dt.MakeGMT();
+ }
+ else switch ( country )
+ {
+ case USA:
+ switch ( year )
+ {
+ case 1918:
+ case 1919:
+ // don't know for sure - assume it was in effect all year
+
+ case 1943:
+ case 1944:
+ case 1945:
+ dt.Set(1, Jan, year);
+ break;
+
+ case 1942:
+ // DST was installed Feb 2, 1942 by the Congress
+ dt.Set(2, Feb, year);
+ break;
+
+ // Oil embargo changed the DST period in the US
+ case 1974:
+ dt.Set(6, Jan, 1974);
+ break;
+
+ case 1975:
+ dt.Set(23, Feb, 1975);
+ break;
+
+ default:
+ // before 1986, DST begun on the last Sunday of April, but
+ // in 1986 Reagan changed it to begin at 2 a.m. of the
+ // first Sunday in April
+ if ( year < 1986 )
+ {
+ if ( !dt.SetToLastWeekDay(Sun, Apr, year) )
+ {
+ // weird...
+ wxFAIL_MSG( _T("no first Sunday in April?") );
+ }
+ }
+ else
+ {
+ if ( !dt.SetToWeekDay(Sun, 1, Apr, year) )
+ {
+ // weird...
+ wxFAIL_MSG( _T("no first Sunday in April?") );
+ }
+ }
+
+ dt += wxTimeSpan::Hours(2);
+
+ // TODO what about timezone??
+ }
+
+ break;
+
+ default:
+ // assume Mar 30 as the start of the DST for the rest of the world
+ // - totally bogus, of course
+ dt.Set(30, Mar, year);
+ }
+
+ return dt;
+}
+
+/* static */
+wxDateTime wxDateTime::GetEndDST(int year, Country country)
+{
+ if ( year == Inv_Year )
+ {
+ // take the current year if none given
+ year = GetCurrentYear();
+ }
+
+ if ( country == Country_Default )
+ {
+ country = GetCountry();
+ }
+
+ if ( !IsDSTApplicable(year, country) )
+ {
+ return ms_InvDateTime;
+ }
+
+ wxDateTime dt;
+
+ if ( IsWestEuropeanCountry(country) || (country == Russia) )
+ {
+ // DST ends at 1 a.m. GMT on the last Sunday of October
+ if ( !dt.SetToLastWeekDay(Sun, Oct, year) )
+ {
+ // weirder and weirder...
+ wxFAIL_MSG( _T("no last Sunday in October?") );
+ }
+
+ dt += wxTimeSpan::Hours(1);
+
+ dt.MakeGMT();
+ }
+ else switch ( country )
+ {
+ case USA:
+ switch ( year )
+ {
+ case 1918:
+ case 1919:
+ // don't know for sure - assume it was in effect all year
+
+ case 1943:
+ case 1944:
+ dt.Set(31, Dec, year);
+ break;
+
+ case 1945:
+ // the time was reset after the end of the WWII
+ dt.Set(30, Sep, year);
+ break;
+
+ default:
+ // DST ends at 2 a.m. on the last Sunday of October
+ if ( !dt.SetToLastWeekDay(Sun, Oct, year) )
+ {
+ // weirder and weirder...
+ wxFAIL_MSG( _T("no last Sunday in October?") );
+ }
+
+ dt += wxTimeSpan::Hours(2);
+
+ // TODO what about timezone??
+ }
+ break;
+
+ default:
+ // assume October 26th as the end of the DST - totally bogus too
+ dt.Set(26, Oct, year);
+ }
+
+ return dt;
+}
+
// ----------------------------------------------------------------------------
// constructors and assignment operators
// ----------------------------------------------------------------------------
// add advance n-1 weeks more
diff += 7*(n - 1);
- dt -= wxDateSpan::Days(diff);
+ dt += wxDateSpan::Days(diff);
}
- else
+ else // count from the end of the month
{
// get the last day of the month
dt.SetToLastMonthDay(month, year);
diff += 7;
// and rewind n-1 weeks from there
- diff += 7*(n - 1);
+ diff += 7*(-n - 1);
dt -= wxDateSpan::Days(diff);
}
}
}
+wxDateTime::wxDateTime_t wxDateTime::GetDayOfYear(const TimeZone& tz) const
+{
+ // this array contains the cumulated number of days in all previous months
+ // for normal and leap years
+ static const wxDateTime_t cumulatedDays[2][MONTHS_IN_YEAR] =
+ {
+ { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334 },
+ { 0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335 }
+ };
+
+ Tm tm(GetTm(tz));
+
+ return cumulatedDays[IsLeapYear(tm.year)][tm.mon] + tm.mday;
+}
+
+wxDateTime::wxDateTime_t wxDateTime::GetWeekOfYear(const TimeZone& tz) const
+{
+ // the first week of the year is the one which contains Jan, 4 (according
+ // to ISO standard rule), so the year day N0 = 4 + 7*W always lies in the
+ // week W+1. As any day N = 7*W + 4 + (N - 4)%7, it lies in the same week
+ // as N0 or in the next one.
+
+ // TODO this surely may be optimized - I got confused while writing it
+
+ wxDateTime_t nDayInYear = GetDayOfYear(tz);
+
+ // the week day of the day lying in the first week
+ WeekDay wdayStart = wxDateTime(4, Jan, GetYear()).GetWeekDay();
+
+ wxDateTime_t week = (nDayInYear - 4) / 7 + 1;
+
+ // notice that Sunday shoould be counted as 7, not 0 here!
+ if ( ((nDayInYear - 4) % 7) + (!wdayStart ? 7 : wdayStart) > 7 )
+ {
+ week++;
+ }
+
+ return week;
+}
+
// ----------------------------------------------------------------------------
// Julian day number conversion and related stuff
// ----------------------------------------------------------------------------
}
else
{
- // wxFAIL_MSG( _T("TODO") );
+ int year = GetYear();
+
+ if ( !IsDSTApplicable(year, country) )
+ {
+ // no DST time in this year in this country
+ return -1;
+ }
- return -1;
+ return IsBetween(GetBeginDST(year, country), GetEndDST(year, country));
}
}
break;
case 'l':
- tmp.Printf(_T("%03d"), GetMilliseconds());
+ tmp.Printf(_T("%03d"), GetMilliseconds().GetValue());
break;
case 'M':
break;
case 'S':
- tmp.Printf(_T("%02d"), GetSeconds());
+ tmp.Printf(_T("%02d"), GetSeconds().GetValue());
break;
}
projects / wxWidgets.git / blobdiff