/* 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 Lesser 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
 * 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 <http://www.gnu.org/licenses/>.
 */

/*
 * Modified by the GTK+ Team and others 1997-2000.  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/. 
 */

#include "config.h"

#include "gdkprivate-x11.h"
#include "gdkscreen-x11.h"
#include "gdkvisual-x11.h"
#include "gdkglcontext-x11.h"

#include <X11/Xlib.h>
#include <X11/Xutil.h>

struct _GdkX11VisualClass
{
  GObjectClass parent_class;
};

G_DEFINE_TYPE (GdkX11Visual, gdk_x11_visual, G_TYPE_OBJECT)

static void
gdk_x11_visual_init (GdkX11Visual *x11_visual)
{
}

static void
gdk_x11_visual_class_init (GdkX11VisualClass *class)
{
}

void
_gdk_x11_screen_init_visuals (GdkX11Screen *x11_screen)
{
  static const int possible_depths[8] = { 32, 30, 24, 16, 15, 8, 4, 1 };
  static const GdkVisualType possible_types[6] =
    {
      GDK_VISUAL_DIRECT_COLOR,
      GDK_VISUAL_TRUE_COLOR,
      GDK_VISUAL_PSEUDO_COLOR,
      GDK_VISUAL_STATIC_COLOR,
      GDK_VISUAL_GRAYSCALE,
      GDK_VISUAL_STATIC_GRAY
    };

  XVisualInfo *visual_list;
  XVisualInfo visual_template;
  Visual *default_xvisual;
  GdkX11Visual **visuals;
  int nxvisuals;
  int nvisuals;
  int i, j;

  nxvisuals = 0;
  visual_template.screen = x11_screen->screen_num;
  visual_list = XGetVisualInfo (x11_screen->xdisplay, VisualScreenMask, &visual_template, &nxvisuals);

  visuals = g_new (GdkX11Visual *, nxvisuals);
  for (i = 0; i < nxvisuals; i++)
    visuals[i] = g_object_new (GDK_TYPE_X11_VISUAL, NULL);

  default_xvisual = DefaultVisual (x11_screen->xdisplay, x11_screen->screen_num);

  nvisuals = 0;
  for (i = 0; i < nxvisuals; i++)
    {
      if (visual_list[i].depth >= 1)
	{
#ifdef __cplusplus
	  switch (visual_list[i].c_class)
#else /* __cplusplus */
	  switch (visual_list[i].class)
#endif /* __cplusplus */
	    {
	    case StaticGray:
	      visuals[nvisuals]->type = GDK_VISUAL_STATIC_GRAY;
	      break;
	    case GrayScale:
	      visuals[nvisuals]->type = GDK_VISUAL_GRAYSCALE;
	      break;
	    case StaticColor:
	      visuals[nvisuals]->type = GDK_VISUAL_STATIC_COLOR;
	      break;
	    case PseudoColor:
	      visuals[nvisuals]->type = GDK_VISUAL_PSEUDO_COLOR;
	      break;
	    case TrueColor:
	      visuals[nvisuals]->type = GDK_VISUAL_TRUE_COLOR;
	      break;
	    case DirectColor:
	      visuals[nvisuals]->type = GDK_VISUAL_DIRECT_COLOR;
	      break;
            default:
              g_warn_if_reached ();
              break;
	    }

	  visuals[nvisuals]->depth = visual_list[i].depth;
	  visuals[nvisuals]->byte_order =
	    (ImageByteOrder(x11_screen->xdisplay) == LSBFirst) ?
	    GDK_LSB_FIRST : GDK_MSB_FIRST;
	  visuals[nvisuals]->red_mask = visual_list[i].red_mask;
	  visuals[nvisuals]->green_mask = visual_list[i].green_mask;
	  visuals[nvisuals]->blue_mask = visual_list[i].blue_mask;
	  visuals[nvisuals]->colormap_size = visual_list[i].colormap_size;
	  visuals[nvisuals]->bits_per_rgb = visual_list[i].bits_per_rgb;
	  GDK_X11_VISUAL (visuals[nvisuals])->xvisual = visual_list[i].visual;

	  if ((visuals[nvisuals]->type != GDK_VISUAL_TRUE_COLOR) &&
	      (visuals[nvisuals]->type != GDK_VISUAL_DIRECT_COLOR))
	    {
	      visuals[nvisuals]->red_mask = 0;
	      visuals[nvisuals]->green_mask = 0;
	      visuals[nvisuals]->blue_mask = 0;
	    }

	  nvisuals += 1;
	}
    }

  if (visual_list)
    XFree (visual_list);

  for (i = 0; i < nvisuals; i++)
    {
      if (default_xvisual->visualid == GDK_X11_VISUAL (visuals[i])->xvisual->visualid)
        x11_screen->system_visual = visuals[i];

      /* For now, we only support 8888 ARGB for the "rgba visual".
       * Additional formats (like ABGR) could be added later if they
       * turn up.
       */
      if (x11_screen->rgba_visual == NULL &&
          visuals[i]->depth == 32 &&
	  (visuals[i]->red_mask   == 0xff0000 &&
	   visuals[i]->green_mask == 0x00ff00 &&
	   visuals[i]->blue_mask  == 0x0000ff))
	{
	  x11_screen->rgba_visual = visuals[i];
        }
    }

#ifdef G_ENABLE_DEBUG
  if (GDK_DISPLAY_DEBUG_CHECK (GDK_SCREEN_DISPLAY (x11_screen), MISC))
    {
      static const char *const visual_names[] =
      {
        "static gray",
        "grayscale",
        "static color",
        "pseudo color",
        "true color",
        "direct color",
      };

      for (i = 0; i < nvisuals; i++)
        g_message ("visual: %s: %d", visual_names[visuals[i]->type], visuals[i]->depth);
    }
#endif /* G_ENABLE_DEBUG */

  x11_screen->navailable_depths = 0;
  for (i = 0; i < G_N_ELEMENTS (possible_depths); i++)
    {
      for (j = 0; j < nvisuals; j++)
	{
	  if (visuals[j]->depth == possible_depths[i])
	    {
	      x11_screen->available_depths[x11_screen->navailable_depths++] = visuals[j]->depth;
	      break;
	    }
	}
    }

  if (x11_screen->navailable_depths == 0)
    g_error ("unable to find a usable depth");

  x11_screen->navailable_types = 0;
  for (i = 0; i < G_N_ELEMENTS (possible_types); i++)
    {
      for (j = 0; j < nvisuals; j++)
	{
	  if (visuals[j]->type == possible_types[i])
	    {
	      x11_screen->available_types[x11_screen->navailable_types++] = visuals[j]->type;
	      break;
	    }
	}
    }

  if (x11_screen->navailable_types == 0)
    g_error ("unable to find a usable visual type");

  x11_screen->visuals = visuals;
  x11_screen->nvisuals = nvisuals;

  /* If GL is available we want to pick better default/rgba visuals,
   * as we care about GLX details such as alpha/depth/stencil depth,
   * stereo and double buffering
   */
  gdk_x11_screen_update_visuals_for_glx (x11_screen);
}

/*< private >
 * gdk_x11_screen_lookup_visual:
 * @screen: a `GdkX11Screen`
 * @xvisualid: an X Visual ID.
 *
 * Looks up the `GdkVisual` for a particular screen and X Visual ID.
 *
 * Returns: (transfer none) (nullable) (type GdkX11Visual): the `GdkVisual`
 */
GdkX11Visual *
gdk_x11_screen_lookup_visual (GdkX11Screen *x11_screen,
                              VisualID   xvisualid)
{
  int i;

  for (i = 0; i < x11_screen->nvisuals; i++)
    if (xvisualid == GDK_X11_VISUAL (x11_screen->visuals[i])->xvisual->visualid)
      return x11_screen->visuals[i];

  return NULL;
}

/*< private >
 * gdk_x11_visual_get_xvisual:
 * @visual: a `GdkX11Visual`
 *
 * Returns the X visual belonging to a `GdkX11Visual`.
 *
 * Returns: (transfer none): an Xlib Visual*.
 **/
Visual *
gdk_x11_visual_get_xvisual (GdkX11Visual *visual)
{
  g_return_val_if_fail (GDK_IS_X11_VISUAL (visual), NULL);

  return GDK_X11_VISUAL (visual)->xvisual;
}