/*
** Copyright (C) 1994, 1995 Enterprise Integration Technologies Corp.
**         VeriFone Inc./Hewlett-Packard. All Rights Reserved.
** Kevin Hughes, kev@kevcom.com 3/11/94
** Kent Landfield, kent@landfield.com 4/6/97
** Tom von Alten, tom_vonalten@boi.hp.com 9 Oct 1998
**
** This program and library is free software; you can redistribute it and/or
** modify it under the terms of the GNU (Library) General Public License
** as published by the Free Software Foundation; either version 2
** of the License, or any later version.
**
** This program is distributed in the hope that it will be useful,
** but WITHOUT ANY WARRANTY; without even the implied warranty of
** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
** GNU (Library) General Public License for more details.
**
** You should have received a copy of the GNU (Library) General Public License
** along with this program; if not, write to the Free Software
** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA 
*/

/*
** Date stuff. Everything here is my own code, with the exception
** of getnweekday(), which is in the public domain. -- Kevin
*/

/*
** Fix routines using two-digit dates, for y2k.  -- TvA
*/

#include "hypermail.h"
#include <time.h>

/* 
** This converts a long date string into the form D/M/Y.
*/

/*
** Returns the day of the year.
*/

int getnweekday(int mn, int dy, int yr)
{
    int n1, n2;

    if (mn < 3) {
        mn += 12;
        yr -= 1;
    }
    n1 = (26 * (mn + 1)) / 10;
    n2 = (int) ((125 * (long) yr) / 100);

    return ((dy + n1 + n2 - (yr / 100) + (yr / 400) + -1) % 7);
}

/*
** Fix to use 4 digit years -- TvA
*/
void convtoshortdate(char *date, char *shortdate)
{
    char c, d, e;
    int i, month;
 

    if (date[3] == ' ') {  /* (Wed Mar 19 19:15:53 1997 CST) format */
        c = date[4];
        d = date[5];
        e = date[6];
 
        for (i = 0; !(c == (months[i])[0] && d == (months[i])[1] &&
           e == (months[i])[2]); i++)
             ;
        month = i + 1;
 
        shortdate[0] = (month > 9) ? '1' : '0';
        shortdate[1] = monthnums[month];
        shortdate[2] = '/';
        shortdate[3] = (date[8] == ' ') ? '0' : date[8];
        shortdate[4] = date[9];
        shortdate[5] = '/';
        shortdate[6] = date[20];
        shortdate[7] = date[21];
        shortdate[8] = date[22];
        shortdate[9] = date[23];
        shortdate[10] = '\0';
    }
    else if (date[3] == ',') { /* (Wed, 19 Mar 19:15:53 1997 CST) */
			       /* (Wed, 19 Mar 19:15:53 97 CST) */
			       /* (Wed, 9 Mar 19:15:53 1997 CST) */
			       /* (Wed, 9 Mar 19:15:53 97 CST) */

        /* Determine the day. */

        if (date[7] == ' ') {   /* Day > 9 */
            c = date[8];
            d = date[9];
            e = date[10];
        }
        else {                  /* Day <= 9 */
            c = date[7];
            d = date[8];
            e = date[9];
        }
      
        /* Determine the month. */

        for (i = 0; !(c == (months[i])[0] && d == (months[i])[1] &&
           e == (months[i])[2]); i++)
             ;
        month = i + 1;
 
        shortdate[0] = (month > 9) ? '1' : '0';
        shortdate[1] = monthnums[month];
        shortdate[2] = '/';

        if (date[4] == ' ' && date[6] == ' ') { /* day < 9 */
            shortdate[3] = '0';
            shortdate[4] = date[5];
        }
        else {
            shortdate[3] = date[5];
            shortdate[4] = date[6];
        }
        shortdate[5] = '/';
  
        /* Determine the year. */
	/* This was looking earlier in the string, as if the time
	   wasn't there?  I changed to match the format in the comment
	   shown above, at "else if" -- TvA */

        /* Two digit year formats assumed to be a 20th century atavism */
  
        if (date[4] == ' ' && date[6] == ' ' && date[10] == ' ') { /* day<9 */
            if (date[22] == ' ') { /* two digit year */
		shortdate[6] = thisyear[0];
		shortdate[7] = thisyear[1];
                shortdate[8] = date[20];
                shortdate[9] = date[21];
            }
            else {
                shortdate[6] = date[20];
                shortdate[7] = date[21];
                shortdate[8] = date[22];
                shortdate[9] = date[23];
            }
        }
        else {
            if (date[23] == ' ') { /* two digit year */
		shortdate[6] = thisyear[0];
		shortdate[7] = thisyear[1];
                shortdate[7] = date[21];
                shortdate[8] = date[22];
            }
            else {
                shortdate[6] = date[21];
                shortdate[7] = date[22];
                shortdate[8] = date[23];
                shortdate[9] = date[24];
            }
        }
        shortdate[10] = '\0';
    }
    else fprintf(stderr,"Date: [%s]\n", date);
}


/*
** Splits a short date (M[M]/D[D]/YYYY) into month, day, and year components.
** Fixed from YY -- TvA
*/

void splitshortdate(char *shortdate, int *month, int *day, int *year)
{
    if (shortdate[0] == ' ' || shortdate[0] == '0')
        *month = (shortdate[1] - '0');
    else if (shortdate[1] == '/')
        *month = (shortdate[0] - '0');
    else if (shortdate[2] == '/')
        *month = (shortdate[0] - '0') * 10 + (shortdate[1] - '0');

    if (shortdate[2] =='/') {
        if (shortdate[5] == '/') {
            *day = (shortdate[3] - '0') * 10 + (shortdate[4] - '0');
            *year = (shortdate[6] - '0') * 1000 + (shortdate[7] - '0') * 100
                    + (shortdate[8] - '0') * 10 + (shortdate[9] - '0');
        }
        else if (shortdate[4] == '/') {
            *day = (shortdate[3] - '0');
            *year = (shortdate[5] - '0') * 1000 + (shortdate[6] - '0') * 100
                    + (shortdate[7] - '0') * 10 + (shortdate[8] - '0');
        }
    }
    else if (shortdate[1] =='/') {
        if (shortdate[4] == '/') {
            *day = (shortdate[2] - '0') * 10 + (shortdate[3] - '0');
            *year = (shortdate[5] - '0') * 1000 + (shortdate[6] - '0') * 100
                    + (shortdate[7] - '0') * 10 + (shortdate[8] - '0');
        }
        else if (shortdate[3] == '/') {
            *day = (shortdate[2] - '0');
            *year = (shortdate[4] - '0') * 1000 + (shortdate[5] - '0') * 100
                    + (shortdate[6] - '0') * 10 + (shortdate[7] - '0');
        }
    }
}

/*
** Given a short date (M/D/YYYY), it returns the number of seconds
** since BASEYEAR.  (Fixed from M/D/YY -- TvA)
*/

long getyearsecs(char *shortdate)
{
    int i, month, day, year;
    long dayspast = 0;

    splitshortdate(shortdate, &month, &day, &year);
/*  year += CENTURY; */

    for (i = BASEYEAR; i < year; i++) {
         if (IS_LEAP(i)) 
             dayspast++;
         dayspast += DAYSPERYEAR;
    }

    for (i = 0; i < month - 1; i++) {
         dayspast += monthdays[i];
    } 

    if (month > 2 && IS_LEAP(year)) 
        dayspast++;
  
    dayspast += day;
 
    return (dayspast * SECSPERDAY);
}

/* 
** Given a long date string, it returns the number of seconds
** since BASEYEAR.
*/

long convtoyearsecs(char *date)
{
    char hourstr[3], minstr[3], secstr[3], shortdate[SHORTDATELEN];
    int hours, minutes, seconds;
    long yearsecs;

    convtoshortdate(date, shortdate);
    yearsecs = getyearsecs(shortdate);

    sprintf(hourstr, "%c%c", date[11], date[12]);
    sprintf(minstr, "%c%c", date[14], date[15]);
    sprintf(secstr, "%c%c", date[17], date[18]);

    hours = atoi(hourstr);
    minutes = atoi(minstr);
    seconds = atoi(secstr);

    return (yearsecs+(hours * SECSPERHOUR)+(minutes * SECSPERMIN)+seconds);
}

/* 
** Gets the local time and returns it formatted.
*/

char *getlocaltime()
{
    static char s[DATESTRLEN];
    time_t tp;

    time(&tp);

    if (eurodate)
        strftime(s,DATESTRLEN,"%a %d %b %Y - %H:%M:%S",localtime(&tp));
    else
        strftime(s,DATESTRLEN,"%a %b %d %Y - %H:%M:%S",localtime(&tp));

    sprintf(s, "%s %s", s, timezonestr);

    return s;
}

/* 
** Gets the local time zone.
*/

void gettimezone()
{
    time_t tp;

    time(&tp);
    strftime(timezonestr, TIMEZONELEN, "%Z", localtime(&tp));
}

/*
** Gets the current year.
*/

void getthisyear()
{
    time_t tp;

    time(&tp);
    strftime(thisyear, YEARLEN, "%Y", localtime(&tp));
}

/* 
** From the number of seconds since BASEYEAR, this pretty-prints
** a date for you.
*/

char *getdatestr(long yearsecs)
{
    register int day, year, month, hours, minutes;
    static char date[DATESTRLEN];

    for (day = 0; yearsecs >= SECSPERDAY; day++)
         yearsecs -= SECSPERDAY;

    for (year = BASEYEAR; day > DAYSPERYEAR; year++) {
         if (IS_LEAP(year))
             day--;
         day -= DAYSPERYEAR;
    }

    for (month = 0; day > monthdays[month]; month++) {
         if (month == 1 && IS_LEAP(year)) {
             if (day == 29)
                 break;
             else
                 day--;
         }
         day -= monthdays[month];
    }

    for (hours = 0; yearsecs >= SECSPERHOUR; hours++)
         yearsecs -= SECSPERHOUR;

    for (minutes = 0; yearsecs >= SECSPERMIN; minutes++)
         yearsecs -= SECSPERMIN;

    if (eurodate) {
        sprintf(date, "%s%s %02d %d - %02d:%02d:%02ld %s",
                days[getnweekday(month + 1, day, year)], months[month],
                day, year, hours, minutes, yearsecs, timezonestr);
    }
    else {
        sprintf(date, "%s%02d %s %d - %02d:%02d:%02ld %s",
                days[getnweekday(month + 1, day, year)], day,
                months[month], year, hours, minutes, yearsecs, timezonestr);
    }
    return date;
}