/*

 * utils.c      -- Various utility functions

 *

 * Copyright (C) 2005-2008 Mikael Berthe <mikael@lilotux.net>

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

 * from_iso8601() comes from the Pidgin (libpurple) 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>

/* For Cygwin (thanks go to Yitzchak Scott-Thoennes) */

#ifdef __CYGWIN__

#  define timezonevar

   extern long timezone;

#endif

#include <time.h>

#include <unistd.h>

#include <sys/types.h>

#include <sys/stat.h>

#include <ctype.h>

#include <glib.h>

#include <config.h>

#include "utils.h"

#include "logprint.h"

static int DebugEnabled;

static char *FName;

//  expand_filename(filename)

// Expand "~/" with the $HOME env. variable in a file name.

// The caller must free the string after use.

char *expand_filename(const char *fname)

{

  if (!fname)

    return NULL;

  if (!strncmp(fname, "~/", 2)) {

    char *homedir = getenv("HOME");

    if (homedir)

      return g_strdup_printf("%s%s", homedir, fname+1);

  }

  return g_strdup(fname);

}

void ut_InitDebug(int level, const char *filename)

{

  FILE *fp;

  struct stat buf;

  int err;

  if (level < 1) {

    DebugEnabled = 0;

    FName = NULL;

    return;

  }

  if (filename)

    FName = expand_filename(filename);

  else {

    FName = getenv("HOME");

    if (!FName)

      FName = g_strdup("/tmp/mcabberlog");

    else {

      FName = g_strdup_printf("%s/mcabberlog", FName);

    }

  }

  DebugEnabled = level;

  fp = fopen(FName, "a");

  if (!fp) {

    fprintf(stderr, "ERROR: Cannot open tracelog file\n");

    return;

  }

  err = fstat(fileno(fp), &buf);

  if (err || buf.st_uid != geteuid()) {

    fclose(fp);

    DebugEnabled = 0;

    FName = NULL;

    if (err) {

      fprintf(stderr, "ERROR: cannot stat the tracelog file!\n");

    } else {

      fprintf(stderr, "ERROR: tracelog file does not belong to you!\n");

    }

    return;

  }

  fchmod(fileno(fp), S_IRUSR|S_IWUSR);

  fprintf(fp, "New trace log started.\n----------------------\n");

  fclose(fp);

}

void ut_WriteLog(unsigned int flag, const char *data)

{

  if (!DebugEnabled || !FName) return;

  if (((DebugEnabled == 2) && (flag & (LPRINT_LOG|LPRINT_DEBUG))) ||

      ((DebugEnabled == 1) && (flag & LPRINT_LOG))) {

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

    if (!fp) {

      scr_LogPrint(LPRINT_NORMAL, "ERROR: Cannot open tracelog file");

      return;

    }

    fclose(fp);

  }

}

//  checkset_perm(name, setmode)

// Check the permissions of the "name" file/dir

// If setmode is true, correct the permissions if they are wrong

// Return values: -1 == bad file/dir, 0 == success, 1 == cannot correct

int checkset_perm(const char *name, unsigned int setmode)

{

  int fd;

  struct stat buf;

#ifdef __CYGWIN__

  // Permission checking isn't efficient on Cygwin

  return 0;

#endif

  fd = stat(name, &buf);

  if (fd == -1) return -1;

  if (buf.st_uid != geteuid()) {

    scr_LogPrint(LPRINT_LOGNORM, "Wrong file owner [%s]", name);

    return 1;

  }

  if (buf.st_mode & (S_IRGRP | S_IWGRP | S_IXGRP) ||

      buf.st_mode & (S_IROTH | S_IWOTH | S_IXOTH)) {

    if (setmode) {

      mode_t newmode = 0;

      scr_LogPrint(LPRINT_LOGNORM, "Bad permissions [%s]", name);

      if (S_ISDIR(buf.st_mode))

        newmode |= S_IXUSR;

      newmode |= S_IRUSR | S_IWUSR;

      if (chmod(name, newmode)) {

        scr_LogPrint(LPRINT_LOGNORM, "WARNING: Failed to correct permissions!");

        return 1;

      }

      scr_LogPrint(LPRINT_LOGNORM, "Permissions have been corrected");

    } else {

      scr_LogPrint(LPRINT_LOGNORM, "WARNING: Bad permissions [%s]", name);

      return 1;

    }

  }

  return 0;

}

const char *ut_get_tmpdir(void)

{

  static const char *tmpdir;

  const char *tmpvars[] = { "MCABBERTMPDIR", "TMP", "TMPDIR", "TEMP" };

  unsigned int i;

  if (tmpdir)

    return tmpdir;

  for (i = 0; i < (sizeof(tmpvars) / sizeof(const char *)); i++) {

    tmpdir = getenv(tmpvars[i]);

    if (tmpdir && tmpdir[0] && tmpdir[0] == '/' && tmpdir[1]) {

      // Looks ok.

      return tmpdir;

    }

  }

  // Default temporary directory

  tmpdir = "/tmp";

  return tmpdir;

}

//  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",

        (int)(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 came from the Pidgin project, gaim_str_to_time().

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

// Thanks, guys!

// ** Modified by somian 10 Apr 2006 with advice from ysth.

time_t from_iso8601(const char *timestamp, int utc)

{

  struct tm t;

  time_t retval = 0;

  char buf[32];

  char *c;

  int tzoff = 0;

  int hms_succ = 0;

  int tmpyear;

  time(&retval);

  localtime_r(&retval, &t);

  /* Reset time to midnight (00:00:00) */

  t.tm_hour = t.tm_min = t.tm_sec = 0;

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

  c = buf;

  /* 4 digit year */

  if (!sscanf(c, "%04d", &tmpyear)) return 0;

  t.tm_year = tmpyear;

  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)

    {

      hms_succ = 1;

      c += 8;

    }

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

    {

       hms_succ = 1;

       c += 6;

    }

    if (hms_succ) {

      int tzhrs, tzmins;

      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;

}

/**

 * Derived from libjabber/jid.c, because the libjabber version is not

 * really convenient for our usage.

 *

 * Check if the full JID is valid

 * Return 0 if it is valid, non zero otherwise

 */

int check_jid_syntax(const char *fjid)

{

  const char *str;

  const char *domain, *resource;

  int domlen;

  if (!fjid) return 1;

  domain = strchr(fjid, JID_DOMAIN_SEPARATOR);

  /* the username is optional */

  if (!domain) {

    domain = fjid;

  } else {

    /* node identifiers may not be longer than 1023 bytes */

    if ((domain == fjid) || (domain-fjid > 1023))

      return 1;

    domain++;

    /* check for low and invalid ascii characters in the username */

    for (str = fjid; *str != JID_DOMAIN_SEPARATOR; str++) {

      if (*str <= ' ' || *str == ':' || *str == JID_DOMAIN_SEPARATOR ||

              *str == '<' || *str == '>' || *str == '\'' ||

              *str == '"' || *str == '&') {

        return 1;

      }

    }

    /* the username is okay as far as we can tell without LIBIDN */

  }

  resource = strchr(domain, JID_RESOURCE_SEPARATOR);

  /* the resource is optional */

  if (resource) {

    domlen = resource - domain;

    resource++;

    /* resources may not be longer than 1023 bytes */

    if ((*resource == '\0') || strlen(resource) > 1023)

      return 1;

  } else {

    domlen = strlen(domain);

  }

  /* there must be a domain identifier */

  if (domlen == 0) return 1;

  /* and it must not be longer than 1023 bytes */

  if (domlen > 1023) return 1;

  /* make sure the hostname is valid characters */

  for (str = domain; *str != '\0' && *str != JID_RESOURCE_SEPARATOR; str++) {

    if (!(isalnum(*str) || *str == '.' || *str == '-' || *str == '_'))

      return 1;

  }

  /* it's okay as far as we can tell without LIBIDN */

  return 0;

}

inline void mc_strtolower(char *str)

{

  if (!str) return;

  for ( ; *str; str++)

    *str = tolower(*str);

}

//  strip_arg_special_chars(string)

// Remove quotes and backslashes before an escaped quote

// Only quotes need a backslash

// Ex.: ["a b"] -> [a b]; [a\"b] -> [a"b]

void strip_arg_special_chars(char *s)

{

  int instring = FALSE;

  int escape = FALSE;

  char *p;

  if (!s) return;