/*
 * util.c
 *
 * by Christian Anthon 2007
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of version 3 or later of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * 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
 *
 * $Id: util.c,v 1.32 2011/08/16 08:27:54 mdpetch Exp $
 */

#include "config.h"
#include "util.h"
#include <glib.h>
#include <stdlib.h>
#include <string.h>
#include "common.h"

char *datadir = NULL;
char *pkg_datadir = NULL;
char *docdir = NULL;
#ifdef WIN32
#include <io.h>

#include <windows.h>
extern void PrintSystemError(const char* message)
{
	LPVOID lpMsgBuf;
	if (FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER | 
		FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS ,
		NULL, GetLastError(), MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
		(LPTSTR) &lpMsgBuf, 0, NULL) != 0)
	{
		g_print("** Windows error while %s **\n", message);
		g_print(": %s", (LPCTSTR)lpMsgBuf);

		if (LocalFree(lpMsgBuf) != NULL)
			g_print("LocalFree() failed\n");
	}
}
#else
#include <errno.h>

extern void PrintSystemError(const char* message)
{
	printf("Unknown system error while %s!\n", message);
}
#endif

extern char *getDataDir(void)
{
	if (!datadir) {
#ifndef WIN32
		datadir = g_strdup(AC_DATADIR);
#else
		char buf[FILENAME_MAX];
		if (GetModuleFileName(NULL, buf, sizeof(buf)) != 0) {
			char *p1 = strrchr(buf, '/'), *p2 = strrchr(buf, '\\');
			int pos1 = (p1 != NULL) ? (int)(p1 - buf) : -1;
			int pos2 = (p2 != NULL) ? (int)(p2 - buf) : -1;
			int pos = MAX(pos1, pos2);
			if (pos > 0)
				buf[pos] = '\0';
			datadir = g_strdup(buf);
		}
#endif
	}
	return datadir;
}

extern char *getPkgDataDir(void)
{
	if (!pkg_datadir)
#ifndef WIN32
		pkg_datadir = g_strdup(AC_PKGDATADIR);
#else
		pkg_datadir = g_build_filename(getDataDir(), NULL);
#endif
	return pkg_datadir;
}

extern char *getDocDir(void)
{
	if (!docdir)
#ifndef WIN32
		docdir = g_strdup(AC_DOCDIR);
#else
		docdir = g_build_filename(getDataDir(), "doc", NULL);
#endif
	return docdir;
}


void PrintError(const char* str)
{
	g_printerr("%s: %s", str, strerror(errno));
}

/* Non-Ansi compliant function */
#ifdef __STRICT_ANSI__
FILE *fdopen(int, const char *);
#endif

/* Temporary version of g_file_open_tmp() as glib version doesn't work
   although this code is copied from glib... */
#ifndef WIN32
#define TEMP_g_file_open_tmp g_file_open_tmp
#else
#include <io.h>
#include <fcntl.h>
#include <errno.h>

int TEMP_g_mkstemp(char *tmpl)
{
  int count, fd;
  static const char letters[] =
    "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
  static const int NLETTERS = sizeof (letters) - 1;
  glong value;
  GTimeVal tv;
  static int counter = 0;
  /* This is where the Xs start.  */
  char *XXXXXX = &tmpl[strlen (tmpl) - 6];

  /* Get some more or less random data.  */
  g_get_current_time (&tv);
  value = (tv.tv_usec ^ tv.tv_sec) + counter++;

  for (count = 0; count < 100; value += 7777, ++count)
  {
      glong v = value;

      /* Fill in the random bits.  */
      XXXXXX[0] = letters[v % NLETTERS];
      v /= NLETTERS;
      XXXXXX[1] = letters[v % NLETTERS];
      v /= NLETTERS;
      XXXXXX[2] = letters[v % NLETTERS];
      v /= NLETTERS;
      XXXXXX[3] = letters[v % NLETTERS];
      v /= NLETTERS;
      XXXXXX[4] = letters[v % NLETTERS];
      v /= NLETTERS;
      XXXXXX[5] = letters[v % NLETTERS];

      fd = open (tmpl, O_RDWR | O_CREAT | O_EXCL | O_BINARY, 0600);

      if (fd >= 0)
        return fd;
      else if (errno != EEXIST)
        /* Any other error will apply also to other names we might
         *  try, and there are 2^32 or so of them, so give up now.
         */
        return -1;
    }

  /* We got out of the loop because we ran out of combinations to try.  */
  return -1;
}

int TEMP_g_file_open_tmp (const char *tmpl, char **name_used, GError **UNUSED(pError))
{
  const char *sep = "";
  char test;
  const char *tmpdir = g_get_tmp_dir ();

  if (tmpl == NULL)
    tmpl = ".XXXXXX";

  test = tmpdir [strlen (tmpdir) - 1];
  if (!G_IS_DIR_SEPARATOR (test))
    sep = G_DIR_SEPARATOR_S;

  *name_used = g_strconcat (tmpdir, sep, tmpl, NULL);
  return TEMP_g_mkstemp(*name_used);
}
/* End of temporary copy of glib code, remove when glib version works on windows... */
#endif

extern FILE *GetTemporaryFile(const char *nameTemplate, char **retName)
{
	FILE *pf;
	int tmpd = TEMP_g_file_open_tmp(nameTemplate, retName, NULL);

	if (tmpd < 0) {
		PrintError("creating temporary file");
		return NULL;
	}

	pf = fdopen(tmpd, "wb+");

	if (pf == NULL) {
		g_free(retName);
		PrintError("opening temporary file");
		return NULL;
	} else
		return pf;
}
