/*

 * utils.c      -- Various utility functions

 * 

 * Copyright (C) 2005 Mikael Berthe <bmikael@lists.lilotux.net>

 * ut_* functions are derived from Cabber debug/log code.

 * from_iso8601() comes from the Gaim project.

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation; either version 2 of the License, or (at

 * your option) 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

 * General Public License for more details.

 *

 * You should have received a copy of the GNU 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

 */

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <stdarg.h>

#include <time.h>

#include <config.h>

static int DebugEnabled;

static char *FName;

{

  FILE *fp;

  if (!level) {

    DebugEnabled = 0;

    FName = NULL;

    return;

  }

  if (filename)

    FName = strdup(filename);

  else {

    FName = getenv("HOME");

    if (!FName)

      FName = "/tmp/mcabberlog";

    else {

      char *tmpname = malloc(strlen(FName) + 12);

      strcpy(tmpname, FName);

      strcat(tmpname, "/mcabberlog");

      FName = tmpname;

    }

  }

  DebugEnabled = level;

  fp = fopen(FName, "w");

  if (!fp) return;

  fprintf(fp, "Debugging mode started...\n"

	  "-----------------------------------\n");

  fclose(fp);

}

void ut_WriteLog(const char *fmt, ...)

{

  FILE *fp = NULL;

  time_t ahora;

  va_list ap;

  char *buffer = NULL;

  if (DebugEnabled && FName) {

    fp = fopen(FName, "a+");

    if (!fp) return;

    buffer = (char *) calloc(1, 64);

    ahora = time(NULL);

    strftime(buffer, 64, "[%H:%M:%S] ", localtime(&ahora));

    fprintf(fp, "%s", buffer);

    va_start(ap, fmt);

    vfprintf(fp, fmt, ap);

    va_end(ap);

    free(buffer);

    fclose(fp);

  }

}

//  to_iso8601(dststr, timestamp)

// Convert timestamp to iso8601 format, and store it in dststr.

// NOTE: dststr should be at last 19 chars long.

// Return should be 0

int to_iso8601(char *dststr, time_t timestamp)

{

  struct tm *tm_time;

  int ret;

  tm_time = gmtime(&timestamp);

  ret = snprintf(dststr, 19, "%.4d%02d%02dT%02d:%02d:%02dZ",

        1900+tm_time->tm_year, tm_time->tm_mon+1, tm_time->tm_mday,

        tm_time->tm_hour, tm_time->tm_min, tm_time->tm_sec);

  return ((ret == -1) ? -1 : 0);

}

//  from_iso8601(timestamp, utc)

// This function comes from the Gaim project, gaim_str_to_time().

// (Actually date may not be pure iso-8601)

// Thanks, guys!

time_t from_iso8601(const char *timestamp, int utc)

{

  struct tm t;

  time_t retval = 0;

  char buf[32];

  char *c;

  int tzoff = 0;

  time(&retval);

  localtime_r(&retval, &t);

  snprintf(buf, sizeof(buf), "%s", timestamp);

  c = buf;

  /* 4 digit year */

  if (!sscanf(c, "%04d", &t.tm_year)) return 0;

  c+=4;

  if (*c == '-')

    c++;

  t.tm_year -= 1900;

  /* 2 digit month */

  if (!sscanf(c, "%02d", &t.tm_mon)) return 0;

  c+=2;

  if (*c == '-')

    c++;

  t.tm_mon -= 1;

  /* 2 digit day */

  if (!sscanf(c, "%02d", &t.tm_mday)) return 0;

  c+=2;

  if (*c == 'T' || *c == '.') { /* we have more than a date, keep going */

    c++; /* skip the "T" */

    /* 2 digit hour */

    if (sscanf(c, "%02d:%02d:%02d", &t.tm_hour, &t.tm_min, &t.tm_sec) == 3 ||

        sscanf(c, "%02d%02d%02d", &t.tm_hour, &t.tm_min, &t.tm_sec) == 3) {

      int tzhrs, tzmins;

      c+=8;

      if (*c == '.') /* dealing with precision we don't care about */

        c += 4;

      if ((*c == '+' || *c == '-') &&

          sscanf(c+1, "%02d:%02d", &tzhrs, &tzmins)) {

        tzoff = tzhrs*60*60 + tzmins*60;

        if (*c == '+')

          tzoff *= -1;

      }

      if (tzoff || utc) {

//#ifdef HAVE_TM_GMTOFF

        tzoff += t.tm_gmtoff;

//#else

//#   ifdef HAVE_TIMEZONE

//        tzset();    /* making sure */

//        tzoff -= timezone;

//#   endif

//#endif

      }

    }

  }

  t.tm_isdst = -1;

  retval = mktime(&t);

  retval += tzoff;

  return retval;

}