/* babl - dynamically extendable universal pixel conversion library.
 * Copyright (C) 2005, Øyvind Kolås.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 3 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General
 * Public License along with this library; if not, see
 * <https://www.gnu.org/licenses/>.
 */

#include "config.h"
#include <stdarg.h>
#include <limits.h>
#include <assert.h>
#include <stdio.h>
#include <math.h>
#include <sys/types.h>
#include <sys/stat.h>
#include "babl-internal.h"

#ifdef _WIN32
#include <windows.h>
#include <wchar.h>
#include <io.h>
#else
#include <sys/time.h>
#include <time.h>
#include <dirent.h>
#endif

#ifdef _WIN32
static LARGE_INTEGER start_time;
static LARGE_INTEGER timer_freq;

static void
init_ticks (void)
{
  static int done = 0;

  if (done)
    return;
  done = 1;

  QueryPerformanceCounter(&start_time);
  QueryPerformanceFrequency(&timer_freq);
}

long
babl_ticks (void)
{
  LARGE_INTEGER end_time;

  init_ticks ();

  QueryPerformanceCounter(&end_time);
  return (end_time.QuadPart - start_time.QuadPart) * (1000000.0 / timer_freq.QuadPart);
}
#else
static struct timeval start_time;

#define usecs(time)    ((time.tv_sec - start_time.tv_sec) * 1000000 + time.tv_usec)

static void
init_ticks (void)
{
  static int done = 0;

  if (done)
    return;
  done = 1;
  gettimeofday (&start_time, NULL);
}

long
babl_ticks (void)
{
  struct timeval measure_time;
  init_ticks ();
  gettimeofday (&measure_time, NULL);
  return usecs (measure_time) - usecs (start_time);
}
#endif

double
babl_rel_avg_error (const double *imgA,
                    const double *imgB,
                    long          samples)
{
  double error = 0.0;
  long   i;

  for (i = 0; i < samples; i++)
    error += fabs (imgA[i] - imgB[i]);

  if (error >= 0.0000001)
    error /= samples;
  else if (error <= 0.0)
    error = 0.0;
  else
    error = M_PI;

  return error;
}

size_t
add_check_overflow (size_t numbers_count, ...)
{
  size_t result = 0;
  va_list args;

  assert (numbers_count > 0);

  va_start (args, numbers_count);
  while (numbers_count--)
    {
      size_t addendum = va_arg (args, size_t);

      if ((SIZE_MAX - result) < addendum)
        {
          result = 0;
          break;
        }

      result += addendum;
    }
  va_end (args);

  return result;
}

size_t
mul_check_overflow (size_t numbers_count, ...)
{
  size_t result = 1;
  va_list args;

  assert (numbers_count > 0);

  va_start (args, numbers_count);
  while (numbers_count--)
    {
      size_t factor = va_arg (args, size_t);

      if ((SIZE_MAX / result) < factor)
        {
          result = 0;
          break;
        }

      result *= factor;
    }
  va_end (args);

  return result;
}

FILE *
_babl_fopen (const char *path,
             const char *mode)
{
#ifndef _WIN32
  return fopen (path, mode);
#else
  wchar_t *path_utf16 = babl_convert_utf8_to_utf16 (path);
  wchar_t *mode_utf16 = babl_convert_utf8_to_utf16 (mode);
  FILE *result = NULL;

#ifndef _WIN64
  result = _wfopen (path_utf16, mode_utf16);
#else
  if (_wfopen_s (&result, path_utf16, mode_utf16) != 0)
    result = NULL;
#endif

  if (path_utf16)
    babl_free (path_utf16);

  if (mode_utf16)
    babl_free (mode_utf16);

  return result;
#endif
}

int
_babl_remove (const char *path)
{
#ifndef _WIN32
  return remove (path);
#else
  wchar_t *path_utf16 = babl_convert_utf8_to_utf16 (path);
  int result = 0;

  result = _wremove (path_utf16);

  if (path_utf16)
    babl_free (path_utf16);

  return result;
#endif
}

int
_babl_rename (const char *oldname,
              const char *newname)
{
#ifndef _WIN32
  return rename (oldname, newname);
#else
  wchar_t *oldname_utf16 = babl_convert_utf8_to_utf16 (oldname);
  wchar_t *newname_utf16 = babl_convert_utf8_to_utf16 (newname);
  int result = 0;

  result = _wrename (oldname_utf16, newname_utf16);

  if (oldname_utf16)
    babl_free (oldname_utf16);

  if (newname_utf16)
    babl_free (newname_utf16);

  return result;
#endif
}

int
_babl_stat (const char *path,
            BablStat   *buffer)
{
#ifndef _WIN32
  return stat (path, buffer);
#else
  wchar_t *path_utf16 = babl_convert_utf8_to_utf16 (path);
  int result = 0;

  result = _wstat64 (path_utf16, buffer);

  if (path_utf16)
    babl_free (path_utf16);

  return result;
#endif
}

int
_babl_mkdir (const char *path,
             int         mode)
{
#ifndef _WIN32
  return mkdir (path, (mode_t) mode);
#else
  wchar_t *path_utf16 = babl_convert_utf8_to_utf16 (path);
  int result = 0;
  (void) mode;

  result = _wmkdir (path_utf16);

  if (path_utf16)
    babl_free (path_utf16);

  return result;
#endif
}

void
_babl_dir_foreach (const char             *path,
                   _babl_dir_foreach_cb_t  callback,
                   void                   *user_data)
{
#ifndef _WIN32
  DIR *dir = opendir (path);

  if (!path)
    return;

  if (dir != NULL)
    {
      struct dirent *dentry;

      while ((dentry = readdir (dir)))
        callback (path, dentry->d_name, user_data);

      closedir (dir);
    }
#else
  char *search = NULL;
  wchar_t *search_utf16 = NULL;
  struct _wfinddata64_t info;
  intptr_t search_id = 0;

  if (!path)
    return;

  search = babl_strcat (search, path);
  search = babl_strcat (search, "\\*");
  search_utf16 = babl_convert_utf8_to_utf16 (search);
  if (!search_utf16)
    goto cleanup;

  memset (&info, 0, sizeof (info));
  if ((search_id = _wfindfirst64 (search_utf16, &info)) != (intptr_t)-1)
    {
      do
        {
          char *entry = babl_convert_utf16_to_utf8 (info.name);

          if (entry)
            {
              callback (path, entry, user_data);
              babl_free (entry);
            }
        }
      while (_wfindnext64 (search_id, &info) == 0);

      _findclose (search_id);
    }

cleanup:
  if (search_utf16)
    babl_free (search_utf16);

  if (search)
    babl_free (search);
#endif
}

int
_babl_file_get_contents (const char  *path,
                         char       **contents,
                         long        *length,
                         void        *error)
{
  FILE *file;
  long  size;
  char *buffer;

  file = _babl_fopen (path, "rb");

  if (!file)
    return -1;

  if (fseek (file, 0, SEEK_END) == -1 || (size = ftell (file)) == -1)
    {
      fclose (file);
      return -1;
    }
  if (length) *length = size;
  rewind (file);
  if ((size_t) size > SIZE_MAX - 8)
    {
      fclose (file);
      return -1;
    }
  buffer = calloc(size + 8, 1);

  if (!buffer)
    {
      fclose(file);
      return -1;
    }

  size -= fread (buffer, 1, size, file);
  if (size)
    {
      fclose (file);
      free (buffer);
      return -1;
    }
  fclose (file);
  *contents = buffer;
  return 0;
}

#ifdef _WIN32

wchar_t *
babl_convert_utf8_to_utf16 (const char *str)
{
  int wchar_count = 0;
  wchar_t *wstr = NULL;

  if (!str)
    return NULL;

  wchar_count = MultiByteToWideChar (CP_UTF8,
                                     MB_ERR_INVALID_CHARS,
                                     str, -1,
                                     NULL, 0);
  if (wchar_count <= 0)
    return NULL;

  wstr = babl_malloc (wchar_count * sizeof (wchar_t));
  if (!wstr)
    return NULL;

  wchar_count = MultiByteToWideChar (CP_UTF8,
                                     MB_ERR_INVALID_CHARS,
                                     str, -1,
                                     wstr, wchar_count);
  if (wchar_count <= 0)
    {
      babl_free (wstr);
      return NULL;
    }

  return wstr;
}

char *
babl_convert_utf16_to_utf8 (const wchar_t *wstr)
{
  int char_count = 0;
  char *str = NULL;

  if (!wstr)
    return NULL;

  char_count = WideCharToMultiByte (CP_UTF8,
                                    WC_ERR_INVALID_CHARS,
                                    wstr, -1,
                                    NULL, 0,
                                    NULL, NULL);
  if (char_count <= 0)
    return NULL;

  str = babl_malloc (char_count);
  if (!str)
    return NULL;

  char_count = WideCharToMultiByte (CP_UTF8,
                                    WC_ERR_INVALID_CHARS,
                                    wstr, -1,
                                    str, char_count,
                                    NULL, NULL);
  if (char_count <= 0)
    {
      babl_free (str);
      return NULL;
    }

  return str;
}

extern IMAGE_DOS_HEADER __ImageBase;

void *
get_libbabl_module (void)
{
  return &__ImageBase;
}

#endif /* _WIN32 */
