/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*************************************************************************
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 *  The Contents of this file are made available subject to the terms of
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 *         - GNU Lesser General Public License Version 2.1
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 *  Sun Microsystems Inc., October, 2000
 *
 *  GNU Lesser General Public License Version 2.1
 *  =============================================
 *  Copyright 2000 by Sun Microsystems, Inc.
 *  901 San Antonio Road, Palo Alto, CA 94303, USA
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
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 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
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 *  Lesser General Public License for more details.
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 *  License along with this library; if not, write to the Free Software
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 *
 *  Sun Industry Standards Source License Version 1.1
 *  =================================================
 *  The contents of this file are subject to the Sun Industry Standards
 *  Source License Version 1.1 (the "License"); You may not use this file
 *  except in compliance with the License. You may obtain a copy of the
 *  License at http://www.openoffice.org/license.html.
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 ************************************************************************/
#include "localtime.hxx"
#include <limits.h>
#include <unicode/timezone.h>
//End by
const long DAY_SEC =24 * 60 * 60;
const long YEAR_SEC = 365 * DAY_SEC;
const long FOURYEAR_SEC = 4 * YEAR_SEC + DAY_SEC;
#ifndef LONG_MAX
const long LONG_MAX=2147483647;
#endif
const long TIMEZONE = -28800;
//01-01-70 was a Thursday
const long BASE_DOW = 4;

long _lpdays[] = {-1, 30, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365};

long _days[] = {-1, 30, 58, 89, 119, 150, 180, 211, 242, 272, 303, 333, 364};

bool LtgGmTime(long rtime,LtTm& rtm)
{
    if (rtime < 0)
    {
        return false;
    }
    //is-current-year-a-leap-year flag
    int islpyr = 0;

    long tmptim;
    long caltim = rtime;
    tmptim = (long)(caltim / FOURYEAR_SEC);
    caltim -= ((long)tmptim * FOURYEAR_SEC);

    //
    //Determine which year of the interval
    //
    // 1970, 1974, 1978,...,etc.
    tmptim = (tmptim * 4) + 70;

    if (caltim >= YEAR_SEC)
    {
        //1971, 1975, 1979,...,etc.
        tmptim++;
        caltim -= YEAR_SEC;

        if ( caltim >= YEAR_SEC )
        {
            // 1972, 1976, 1980,...,etc.
            tmptim++;
            caltim -= YEAR_SEC;

            //Note, it takes 366 days-worth of seconds to get past a leap year.
            if (caltim >= (YEAR_SEC + DAY_SEC))
            {
                //1973, 1977, 1981,...,etc.
                tmptim++;
                caltim -= (YEAR_SEC + DAY_SEC);
            }
            else
            {
                //In a leap year after all, set the flag.
                islpyr++;
            }
        }
    }

    //
    //tmptim now holds the value for tm_year. caltim now holds the
    //number of elapsed seconds since the beginning of that year.
    //
    rtm.tm_year = tmptim;
    //
    //Determine days since January 1 (0 - 365). This is the tm_yday value.
    //Leave caltim with number of elapsed seconds in that day.
    //
    rtm.tm_yday = (long)(caltim / DAY_SEC);
    caltim -= (long)(rtm.tm_yday) * DAY_SEC;
    //
    //Determine months since January (0 - 11) and day of month (1 - 31)
    //
    long* mdays;
    if ( islpyr )
    {
        mdays = _lpdays;
    }
    else
    {
        mdays = _days;
    }

    for ( tmptim = 1 ; mdays[tmptim] < rtm.tm_yday ; tmptim++ ) ;

    rtm.tm_mon = --tmptim;

    rtm.tm_mday = rtm.tm_yday - mdays[tmptim];

    //
    //Determine days since Sunday (0 - 6)
    //
    rtm.tm_wday = ((long)(rtime / DAY_SEC) + BASE_DOW) % 7;
    //
    //Determine hours since midnight (0 - 23), minutes after the hour
    //(0 - 59), and seconds after the minute (0 - 59).
    //
    rtm.tm_hour = (long)(caltim / 3600);
    caltim -= (long)rtm.tm_hour * 3600;

    rtm.tm_min = (long)(caltim / 60);
    rtm.tm_sec = (long)(caltim - (rtm.tm_min) * 60);

    rtm.tm_isdst = 0;

    //
    //
    //
    //adjust year & month
    rtm.tm_year += 1900;
    ++(rtm.tm_mon);

    return true;

};
bool LtgLocalTime(long rtime,LtTm& rtm)
{
    if (rtime < 0)
    {
        return false;
    }

    if ((rtime > 3 * DAY_SEC)&&(rtime < LONG_MAX - 3 * DAY_SEC))
    {
        TimeZone* pLocalZone = TimeZone::createDefault();
        long offset = (pLocalZone->getRawOffset())/1000;
        delete pLocalZone;
        long ltime = rtime + offset;
        return LtgGmTime(ltime,rtm);
    }
    return false;
};

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