/* Clutter.
 * An OpenGL based 'interactive canvas' library.
 * Authored By Matthew Allum  <mallum@openedhand.com>
 * Copyright (C) 2006-2007 OpenedHand
 *
 * 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/>.
 *
 *
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <glib/gi18n-lib.h>

#include <string.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <fcntl.h>
#include <errno.h>

#include <gdk/gdk.h>
#include <cogl/cogl.h>

#include <cogl/cogl-xlib.h>

#ifdef GDK_WINDOWING_X11
#include <gdk/gdkx.h>
#endif

#ifdef GDK_WINDOWING_WIN32
#include <gdk/gdkwin32.h>
#endif

#include "clutter-backend-gdk.h"
#include "clutter-device-manager-gdk.h"
#include "clutter-settings-gdk.h"
#include "clutter-stage-gdk.h"
#include "clutter-gdk.h"

#include "clutter-backend.h"
#include "clutter-debug.h"
#include "clutter-device-manager-private.h"
#include "clutter-event-private.h"
#include "clutter-main.h"
#include "clutter-private.h"

#define clutter_backend_gdk_get_type _clutter_backend_gdk_get_type
G_DEFINE_TYPE (ClutterBackendGdk, clutter_backend_gdk, CLUTTER_TYPE_BACKEND_COGL);

/* global for pre init setup calls */
static GdkDisplay  *_foreign_dpy = NULL;

static void
clutter_backend_gdk_init_settings (ClutterBackendGdk *backend_gdk)
{
  ClutterSettings *settings = clutter_settings_get_default ();
  int i;

  for (i = 0; i < G_N_ELEMENTS (_clutter_settings_map); i++)
    {
      GValue val = G_VALUE_INIT;

      g_value_init (&val, CLUTTER_SETTING_TYPE(i));
      gdk_screen_get_setting (backend_gdk->screen,
			      CLUTTER_SETTING_GDK_NAME(i),
			      &val);
      g_object_set_property (G_OBJECT (settings),
			     CLUTTER_SETTING_PROPERTY(i),
			     &val);
      g_value_unset (&val);
    }
}

void
_clutter_backend_gdk_update_setting (ClutterBackendGdk *backend_gdk,
				     const gchar       *setting_name)
{
  ClutterSettings *settings = clutter_settings_get_default ();
  int i;

  for (i = 0; i < G_N_ELEMENTS (_clutter_settings_map); i++)
    {
      if (g_strcmp0 (CLUTTER_SETTING_GDK_NAME (i), setting_name) == 0)
	{
	  GValue val = G_VALUE_INIT;

	  g_value_init (&val, CLUTTER_SETTING_TYPE (i));
	  gdk_screen_get_setting (backend_gdk->screen,
				  CLUTTER_SETTING_GDK_NAME (i),
				  &val);
	  g_object_set_property (G_OBJECT (settings),
				 CLUTTER_SETTING_PROPERTY (i),
				 &val);
	  g_value_unset (&val);

	  break;
	}
    }
}

static GdkFilterReturn
cogl_gdk_filter (GdkXEvent  *xevent,
		 GdkEvent   *event,
		 gpointer    data)
{
#ifdef GDK_WINDOWING_X11
  CoglFilterReturn ret;

  ret = cogl_xlib_handle_event ((XEvent*)xevent);
  switch (ret)
    {
    case COGL_FILTER_REMOVE:
      return GDK_FILTER_REMOVE;

    case COGL_FILTER_CONTINUE:
    default:
      return GDK_FILTER_CONTINUE;
    }
#endif
}

static gboolean
_clutter_backend_gdk_post_parse (ClutterBackend  *backend,
                                 GError         **error)
{
  ClutterBackendGdk *backend_gdk = CLUTTER_BACKEND_GDK (backend);

  if (_foreign_dpy != NULL)
    backend_gdk->display = _foreign_dpy;

  /* Init Gdk, if outside code did not already */
  if (!gdk_init_check (NULL, NULL))
    return FALSE;

  /*
   * Only open connection if not already set by prior call to
   * clutter_gdk_set_display()
   */
  if (backend_gdk->display == NULL)
    backend_gdk->display = g_object_ref (gdk_display_get_default ());

  g_assert (backend_gdk->display != NULL);

#ifdef GDK_WINDOWING_X11
  if (GDK_IS_X11_DISPLAY (backend_gdk->display))
    {
      /* Cogl needs to know the Xlib display connection for
	 CoglTexturePixmapX11 */
      cogl_xlib_set_display (gdk_x11_display_get_xdisplay (backend_gdk->display));
    }
#endif

  backend_gdk->screen = gdk_display_get_default_screen (backend_gdk->display);

  /* add event filter for Cogl events */
  gdk_window_add_filter (NULL, cogl_gdk_filter, NULL);

  clutter_backend_gdk_init_settings (backend_gdk);

  CLUTTER_NOTE (BACKEND,
                "Gdk Display '%s' opened",
                gdk_display_get_name (backend_gdk->display));

  return CLUTTER_BACKEND_CLASS (clutter_backend_gdk_parent_class)->post_parse (backend,
									       error);
}


static void
clutter_backend_gdk_init_events (ClutterBackend *backend)
{
  CLUTTER_NOTE (EVENT, "initialising the event loop");

  _clutter_backend_gdk_events_init (backend);
}

static void
clutter_backend_gdk_finalize (GObject *gobject)
{
  ClutterBackendGdk *backend_gdk = CLUTTER_BACKEND_GDK (gobject);

  gdk_window_remove_filter (NULL, cogl_gdk_filter, NULL);
  g_object_unref (backend_gdk->display);

  G_OBJECT_CLASS (clutter_backend_gdk_parent_class)->finalize (gobject);
}

static void
clutter_backend_gdk_dispose (GObject *gobject)
{
  ClutterBackendGdk   *backend_gdk = CLUTTER_BACKEND_GDK (gobject);
  ClutterStageManager *stage_manager;

  CLUTTER_NOTE (BACKEND, "Disposing the of stages");
  stage_manager = clutter_stage_manager_get_default ();

  g_object_unref (stage_manager);

  CLUTTER_NOTE (BACKEND, "Removing the event source");
  _clutter_backend_gdk_events_uninit (CLUTTER_BACKEND (backend_gdk));

  G_OBJECT_CLASS (clutter_backend_gdk_parent_class)->dispose (gobject);
}

static ClutterFeatureFlags
clutter_backend_gdk_get_features (ClutterBackend *backend)
{
  ClutterFeatureFlags flags = CLUTTER_FEATURE_STAGE_USER_RESIZE | CLUTTER_FEATURE_STAGE_CURSOR;

  flags |= CLUTTER_BACKEND_CLASS (clutter_backend_gdk_parent_class)->get_features (backend);

  return flags;
}

static void
clutter_backend_gdk_copy_event_data (ClutterBackend     *backend,
                                     const ClutterEvent *src,
                                     ClutterEvent       *dest)
{
  GdkEvent *gdk_event;

  gdk_event = _clutter_event_get_platform_data (src);
  if (gdk_event != NULL)
    _clutter_event_set_platform_data (dest, gdk_event_copy (gdk_event));
}

static void
clutter_backend_gdk_free_event_data (ClutterBackend *backend,
                                     ClutterEvent   *event)
{
  GdkEvent *gdk_event;

  gdk_event = _clutter_event_get_platform_data (event);
  if (gdk_event != NULL)
    gdk_event_free (gdk_event);
}

static ClutterDeviceManager *
clutter_backend_gdk_get_device_manager (ClutterBackend *backend)
{
  ClutterBackendGdk *backend_gdk = CLUTTER_BACKEND_GDK (backend);

  if (G_UNLIKELY (backend_gdk->device_manager == NULL))
    {
      backend_gdk->device_manager = g_object_new (CLUTTER_TYPE_DEVICE_MANAGER_GDK,
						  "backend", backend_gdk,
						  "gdk-display", backend_gdk->display,
						  NULL);
    }

  return backend_gdk->device_manager;
}

static gboolean
clutter_backend_gdk_create_context (ClutterBackend  *backend,
				    GError         **error)
{
  ClutterBackendGdk *backend_gdk = CLUTTER_BACKEND_GDK (backend);
  CoglSwapChain *swap_chain = NULL;
  CoglOnscreenTemplate *onscreen_template = NULL;
  GdkVisual *rgba_visual = NULL;

  if (backend->cogl_context != NULL)
    return TRUE;

  backend->cogl_renderer = cogl_renderer_new ();

#if defined(GDK_WINDOWING_X11) && defined(COGL_HAS_XLIB_SUPPORT)
  if (GDK_IS_X11_DISPLAY (backend_gdk->display))
    {
      cogl_xlib_renderer_set_foreign_display (backend->cogl_renderer,
					      gdk_x11_display_get_xdisplay (backend_gdk->display));
    }
  else
#endif
#if defined(GDK_WINDOWING_WIN32)
  if (GDK_IS_WIN32_DISPLAY (backend_gdk->display))
    {
      /* Force a WGL winsys on windows */
      cogl_renderer_set_winsys_id (backend_cogl->cogl_renderer, COGL_WINSYS_ID_WGL);
    }
  else
#endif
    {
      g_set_error (error, CLUTTER_INIT_ERROR,
                   CLUTTER_INIT_ERROR_BACKEND,
                   "Could not find a suitable CoglWinsys for"
                   "a GdkDisplay of type %s", G_OBJECT_TYPE_NAME (backend_gdk->display));
      goto error;
    }


  if (!cogl_renderer_connect (backend->cogl_renderer, error))
    goto error;

  swap_chain = cogl_swap_chain_new ();

  rgba_visual = gdk_screen_get_rgba_visual (backend_gdk->screen);
  cogl_swap_chain_set_has_alpha (swap_chain, rgba_visual != NULL);

  onscreen_template = cogl_onscreen_template_new (swap_chain);
  cogl_object_unref (swap_chain);

  /* XXX: I have some doubts that this is a good design.
   * Conceptually should we be able to check an onscreen_template
   * without more details about the CoglDisplay configuration?
   */
  if (!cogl_renderer_check_onscreen_template (backend->cogl_renderer,
                                              onscreen_template,
                                              error))
    goto error;

  backend->cogl_display = cogl_display_new (backend->cogl_renderer,
                                            onscreen_template);

  cogl_object_unref (backend->cogl_renderer);
  cogl_object_unref (onscreen_template);

  if (!cogl_display_setup (backend->cogl_display, error))
    goto error;

  backend->cogl_context = cogl_context_new (backend->cogl_display, error);
  if (backend->cogl_context == NULL)
    goto error;

  return TRUE;

error:
  if (backend->cogl_display != NULL)
    {
      cogl_object_unref (backend->cogl_display);
      backend->cogl_display = NULL;
    }

  if (onscreen_template != NULL)
    cogl_object_unref (onscreen_template);
  if (swap_chain != NULL)
    cogl_object_unref (swap_chain);

  if (backend->cogl_renderer != NULL)
    {
      cogl_object_unref (backend->cogl_renderer);
      backend->cogl_renderer = NULL;
    }
  return FALSE;
}

static ClutterStageWindow *
clutter_backend_gdk_create_stage (ClutterBackend  *backend,
				  ClutterStage    *wrapper,
				  GError         **error)
{
  return g_object_new (CLUTTER_TYPE_STAGE_GDK,
		       "backend", backend,
		       "wrapper", wrapper,
		       NULL);
}

static void
clutter_backend_gdk_class_init (ClutterBackendGdkClass *klass)
{
  GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
  ClutterBackendClass *backend_class = CLUTTER_BACKEND_CLASS (klass);

  gobject_class->dispose = clutter_backend_gdk_dispose;
  gobject_class->finalize = clutter_backend_gdk_finalize;

  backend_class->post_parse = _clutter_backend_gdk_post_parse;
  backend_class->init_events = clutter_backend_gdk_init_events;
  backend_class->get_features = clutter_backend_gdk_get_features;
  backend_class->get_device_manager = clutter_backend_gdk_get_device_manager;
  backend_class->copy_event_data = clutter_backend_gdk_copy_event_data;
  backend_class->free_event_data = clutter_backend_gdk_free_event_data;
  backend_class->create_context = clutter_backend_gdk_create_context;
  backend_class->create_stage = clutter_backend_gdk_create_stage;
}

static void
clutter_backend_gdk_init (ClutterBackendGdk *backend_gdk)
{
  /* nothing to do here */
}

/**
 * clutter_gdk_get_default_display:
 *
 * Retrieves the pointer to the default display.
 *
 * Return value: (transfer none): the default display
 *
 * Since: 0.6
 */
GdkDisplay *
clutter_gdk_get_default_display (void)
{
  ClutterBackend *backend = clutter_get_default_backend ();

  if (backend == NULL)
    {
      g_critical ("The Clutter backend has not been initialised");
      return NULL;
    }

  if (!CLUTTER_IS_BACKEND_GDK (backend))
    {
      g_critical ("The Clutter backend is not a GDK backend");
      return NULL;
    }

  return CLUTTER_BACKEND_GDK (backend)->display;
}

/**
 * clutter_gdk_set_display:
 * @display: pointer to a GDK display connection.
 *
 * Sets the display connection Clutter should use; must be called
 * before clutter_init(), clutter_init_with_args() or other functions
 * pertaining Clutter's initialization process.
 *
 * If you are parsing the command line arguments by retrieving Clutter's
 * #GOptionGroup with clutter_get_option_group() and calling
 * g_option_context_parse() yourself, you should also call
 * clutter_gdk_set_display() before g_option_context_parse().
 *
 * Since: 0.8
 */
void
clutter_gdk_set_display (GdkDisplay *display)
{
  if (_clutter_context_is_initialized ())
    {
      g_warning ("%s() can only be used before calling clutter_init()",
                 G_STRFUNC);
      return;
    }

  _foreign_dpy = g_object_ref (display);
}