/* Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (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.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "apr_portable.h"
#include "apr_time.h"
#include "apr_lib.h"
#include "apr_private.h"
/* System Headers required for time library */
#if APR_HAVE_SYS_TIME_H
#include <sys/time.h>
#endif
#ifdef HAVE_TIME_H
#include <time.h>
#endif
#if APR_HAVE_STRING_H
#include <string.h>
#endif
/* End System Headers */

APR_DECLARE_DATA const char apr_month_snames[12][4] =
{
    "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
};
APR_DECLARE_DATA const char apr_day_snames[7][4] =
{
    "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
};

apr_status_t apr_rfc822_date(char *date_str, apr_time_t t)
{
    apr_time_exp_t xt;
    const char *s;
    int real_year;

    apr_time_exp_gmt(&xt, t);

    /* example: "Sat, 08 Jan 2000 18:31:41 GMT" */
    /*           12345678901234567890123456789  */

    s = &apr_day_snames[xt.tm_wday][0];
    *date_str++ = *s++;
    *date_str++ = *s++;
    *date_str++ = *s++;
    *date_str++ = ',';
    *date_str++ = ' ';
    *date_str++ = xt.tm_mday / 10 + '0';
    *date_str++ = xt.tm_mday % 10 + '0';
    *date_str++ = ' ';
    s = &apr_month_snames[xt.tm_mon][0];
    *date_str++ = *s++;
    *date_str++ = *s++;
    *date_str++ = *s++;
    *date_str++ = ' ';
    real_year = 1900 + xt.tm_year;
    /* This routine isn't y10k ready. */
    *date_str++ = real_year / 1000 + '0';
    *date_str++ = real_year % 1000 / 100 + '0';
    *date_str++ = real_year % 100 / 10 + '0';
    *date_str++ = real_year % 10 + '0';
    *date_str++ = ' ';
    *date_str++ = xt.tm_hour / 10 + '0';
    *date_str++ = xt.tm_hour % 10 + '0';
    *date_str++ = ':';
    *date_str++ = xt.tm_min / 10 + '0';
    *date_str++ = xt.tm_min % 10 + '0';
    *date_str++ = ':';
    *date_str++ = xt.tm_sec / 10 + '0';
    *date_str++ = xt.tm_sec % 10 + '0';
    *date_str++ = ' ';
    *date_str++ = 'G';
    *date_str++ = 'M';
    *date_str++ = 'T';
    *date_str++ = 0;
    return APR_SUCCESS;
}

apr_status_t apr_ctime(char *date_str, apr_time_t t)
{
    apr_time_exp_t xt;
    const char *s;
    int real_year;

    /* example: "Wed Jun 30 21:49:08 1993" */
    /*           123456789012345678901234  */

    apr_time_exp_lt(&xt, t);
    s = &apr_day_snames[xt.tm_wday][0];
    *date_str++ = *s++;
    *date_str++ = *s++;
    *date_str++ = *s++;
    *date_str++ = ' ';
    s = &apr_month_snames[xt.tm_mon][0];
    *date_str++ = *s++;
    *date_str++ = *s++;
    *date_str++ = *s++;
    *date_str++ = ' ';
    *date_str++ = xt.tm_mday / 10 + '0';
    *date_str++ = xt.tm_mday % 10 + '0';
    *date_str++ = ' ';
    *date_str++ = xt.tm_hour / 10 + '0';
    *date_str++ = xt.tm_hour % 10 + '0';
    *date_str++ = ':';
    *date_str++ = xt.tm_min / 10 + '0';
    *date_str++ = xt.tm_min % 10 + '0';
    *date_str++ = ':';
    *date_str++ = xt.tm_sec / 10 + '0';
    *date_str++ = xt.tm_sec % 10 + '0';
    *date_str++ = ' ';
    real_year = 1900 + xt.tm_year;
    *date_str++ = real_year / 1000 + '0';
    *date_str++ = real_year % 1000 / 100 + '0';
    *date_str++ = real_year % 100 / 10 + '0';
    *date_str++ = real_year % 10 + '0';
    *date_str++ = 0;

    return APR_SUCCESS;
}

apr_status_t apr_strftime(char *s, apr_size_t *retsize, apr_size_t max, 
                        const char *format, apr_time_exp_t *xt)
{
    struct tm tm;
    memset(&tm, 0, sizeof tm);
    tm.tm_sec  = xt->tm_sec;
    tm.tm_min  = xt->tm_min;
    tm.tm_hour = xt->tm_hour;
    tm.tm_mday = xt->tm_mday;
    tm.tm_mon  = xt->tm_mon;
    tm.tm_year = xt->tm_year;
    tm.tm_wday = xt->tm_wday;
    tm.tm_yday = xt->tm_yday;
    tm.tm_isdst = xt->tm_isdst;
#if defined(HAVE_STRUCT_TM_TM_GMTOFF)
    tm.tm_gmtoff = xt->tm_gmtoff;
#elif defined(HAVE_STRUCT_TM___TM_GMTOFF)
    tm.__tm_gmtoff = xt->tm_gmtoff;
#endif
    (*retsize) = strftime(s, max, format, &tm);
    return APR_SUCCESS;
}