/* GDK - The GIMP Drawing Kit
 * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 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
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */

/*
 * Modified by the GTK+ Team and others 1997-1999.  See the AUTHORS
 * file for a list of people on the GTK+ Team.  See the ChangeLog
 * files for a list of changes.  These files are distributed with
 * GTK+ at ftp://ftp.gtk.org/pub/gtk/. 
 */

#if HAVE_CONFIG_H
#  include <config.h>
#endif

#include <stdlib.h>
#include <string.h>

#include "gdkim.h"
#include "gdkpixmap.h"
#include "gdkprivate.h"
#include "gdki18n.h"
#include "gdkx.h"

/*
 *--------------------------------------------------------------
 * gdk_set_locale
 *
 * Arguments:
 *
 * Results:
 *
 * Side effects:
 *
 *--------------------------------------------------------------
 */

gchar*
gdk_set_locale (void)
{
  gchar *current_locale;

  if (!setlocale (LC_ALL,""))
    g_warning ("locale not supported by C library");
  
  current_locale = setlocale (LC_ALL, NULL);

  return current_locale;
}

void 
gdk_im_begin (GdkIC *ic, GdkWindow* window)
{
}

void 
gdk_im_end (void)
{
}

GdkIMStyle
gdk_im_decide_style (GdkIMStyle supported_style)
{
  return GDK_IM_PREEDIT_NONE | GDK_IM_STATUS_NONE;
}

GdkIMStyle
gdk_im_set_best_style (GdkIMStyle style)
{
  return GDK_IM_PREEDIT_NONE | GDK_IM_STATUS_NONE;
}

gint 
gdk_im_ready (void)
{
  return FALSE;
}

GdkIC * 
gdk_ic_new (GdkICAttr *attr, GdkICAttributesType mask)
{
  return NULL;
}

void 
gdk_ic_destroy (GdkIC *ic)
{
}

GdkIMStyle
gdk_ic_get_style (GdkIC *ic)
{
  return GDK_IM_PREEDIT_NONE | GDK_IM_STATUS_NONE;
}

void 
gdk_ic_set_values (GdkIC *ic, ...)
{
}

void 
gdk_ic_get_values (GdkIC *ic, ...)
{
}

GdkICAttributesType 
gdk_ic_set_attr (GdkIC *ic, GdkICAttr *attr, GdkICAttributesType mask)
{
  return 0;
}

GdkICAttributesType 
gdk_ic_get_attr (GdkIC *ic, GdkICAttr *attr, GdkICAttributesType mask)
{
  return 0;
}

GdkEventMask 
gdk_ic_get_events (GdkIC *ic)
{
  return 0;
}

/*
 * gdk_wcstombs 
 *
 * Returns a multi-byte string converted from the specified array
 * of wide characters. The string is newly allocated. The array of
 * wide characters must be null-terminated. If the conversion is
 * failed, it returns NULL.
 *
 * On Win32, we always use UTF-8.
 */
gchar *
gdk_wcstombs (const GdkWChar *src)
{
  gint len;
  const GdkWChar *wcp;
  guchar *mbstr, *bp;

  wcp = src;
  len = 0;
  while (*wcp)
    {
      const GdkWChar c = *wcp++;

      if (c < 0x80)
	len += 1;
      else if (c < 0x800)
	len += 2;
      else if (c < 0x10000)
	len += 3;
      else if (c < 0x200000)
	len += 4;
      else if (c < 0x4000000)
	len += 5;
      else
	len += 6;
    }

  mbstr = g_malloc (len + 1);
  
  wcp = src;
  bp = mbstr;
  while (*wcp)
    {
      int first;
      int i;
      GdkWChar c = *wcp++;

      if (c < 0x80)
	{
	  first = 0;
	  len = 1;
	}
      else if (c < 0x800)
	{
	  first = 0xc0;
	  len = 2;
	}
      else if (c < 0x10000)
	{
	  first = 0xe0;
	  len = 3;
	}
      else if (c < 0x200000)
	{
	  first = 0xf0;
	  len = 4;
	}
      else if (c < 0x4000000)
	{
	  first = 0xf8;
	  len = 5;
	}
      else
	{
	  first = 0xfc;
	  len = 6;
	}
      
      /* Woo-hoo! */
      switch (len)
	{
	case 6: bp[5] = (c & 0x3f) | 0x80; c >>= 6; /* Fall through */
	case 5: bp[4] = (c & 0x3f) | 0x80; c >>= 6; /* Fall through */
	case 4: bp[3] = (c & 0x3f) | 0x80; c >>= 6; /* Fall through */
	case 3: bp[2] = (c & 0x3f) | 0x80; c >>= 6; /* Fall through */
	case 2: bp[1] = (c & 0x3f) | 0x80; c >>= 6; /* Fall through */
	case 1: bp[0] = c | first;
	}

      bp += len;
    }
  *bp = 0;
  return mbstr;
}

  
/*
 * gdk_mbstowcs
 *
 * Converts the specified string into GDK wide characters, and,
 * returns the number of wide characters written. The string 'src'
 * must be null-terminated. If the conversion is failed, it returns
 * -1.
 *
 * On Win32, thr string is assumed to be in UTF-8.  Also note that
 * GdkWChar is 32 bits, while wchar_t, and the wide characters the
 * Windows API uses, are 16 bits!
 */

/* First a helper function for not zero-terminated strings */
gint
gdk_nmbstowcs (GdkWChar    *dest,
	       const gchar *src,
	       gint         src_len,
	       gint         dest_max)
{
  guchar *cp, *end;
  gint n;
  
  cp = (guchar *) src;
  end = cp + src_len;
  n = 0;
  while (cp != end && dest != dest + dest_max)
    {
      gint i, mask = 0, len;
      guchar c = *cp;

      if (c < 0x80)
	{
	  len = 1;
	  mask = 0x7f;
	}
      else if ((c & 0xe0) == 0xc0)
	{
	  len = 2;
	  mask = 0x1f;
	}
      else if ((c & 0xf0) == 0xe0)
	{
	  len = 3;
	  mask = 0x0f;
	}
      else if ((c & 0xf8) == 0xf0)
	{
	  len = 4;
	  mask = 0x07;
	}
      else if ((c & 0xfc) == 0xf8)
	{
	  len = 5;
	  mask = 0x03;
	}
      else if ((c & 0xfc) == 0xfc)
	{
	  len = 6;
	  mask = 0x01;
	}
      else
	return -1;

      if (cp + len > end)
	return -1;

      *dest = (cp[0] & mask);
      for (i = 1; i < len; i++)
	{
	  if ((cp[i] & 0xc0) != 0x80)
	    return -1;
	  *dest <<= 6;
	  *dest |= (cp[i] & 0x3f);
	}
      if (*dest == -1)
	return -1;

      cp += len;
      dest++;
      n++;
    }
  if (cp != end)
    return -1;

  return n;
}

gint
gdk_mbstowcs (GdkWChar    *dest,
	      const gchar *src,
	      gint         dest_max)
{
  return gdk_nmbstowcs (dest, src, strlen (src), dest_max);
}


/* A version that converts to wchar_t wide chars */

gint
gdk_nmbstowchar_ts (wchar_t     *dest,
		    const gchar *src,
		    gint         src_len,
		    gint         dest_max)
{
  guchar *cp, *end;
  gint n;
  
  cp = (guchar *) src;
  end = cp + src_len;
  n = 0;
  while (cp != end && dest != dest + dest_max)
    {
      gint i, mask = 0, len;
      guchar c = *cp;

      if (c < 0x80)
	{
	  len = 1;
	  mask = 0x7f;
	}
      else if ((c & 0xe0) == 0xc0)
	{
	  len = 2;
	  mask = 0x1f;
	}
      else if ((c & 0xf0) == 0xe0)
	{
	  len = 3;
	  mask = 0x0f;
	}
      else /* Other lengths are not possible with 16-bit wchar_t! */
	return -1;

      if (cp + len > end)
	return -1;

      *dest = (cp[0] & mask);
      for (i = 1; i < len; i++)
	{
	  if ((cp[i] & 0xc0) != 0x80)
	    return -1;
	  *dest <<= 6;
	  *dest |= (cp[i] & 0x3f);
	}
      if (*dest == 0xFFFF)
	return -1;

      cp += len;
      dest++;
      n++;
    }
  if (cp != end)
    return -1;

  return n;
}