/* ATK - Accessibility Toolkit

 * Copyright 2001, 2002, 2003 Sun Microsystems Inc.

 *

 * 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, write to the

 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,

 * Boston, MA 02111-1307, USA.

 */

#include "config.h"

#include <atk/atkgobjectaccessible.h>

#include <atk/atkregistry.h>

#include <atk/atkutil.h>

/**

 * SECTION:atkgobjectaccessible

 * @Short_description: This object class is derived from AtkObject and

 *  can be used as a basis implementing accessible objects.

 * @Title:AtkGObjectAccessible

 *

 * This object class is derived from AtkObject. It can be used as a

 * basis for implementing accessible objects for GObjects which are

 * not derived from GtkWidget. One example of its use is in providing

 * an accessible object for GnomeCanvasItem in the GAIL library.

 */

static void       atk_gobject_accessible_class_init       (AtkGObjectAccessibleClass   *klass);

static void       atk_real_gobject_accessible_initialize  (AtkObject         *atk_obj,

                                                           gpointer          data);

static void       atk_gobject_accessible_object_gone_cb   (gpointer          data);

static GQuark quark_accessible_object = 0;

static GQuark quark_object = 0;

static gpointer parent_class = NULL;

GType

atk_gobject_accessible_get_type (void)

{

  static GType type = 0;

  if (!type)

    {

      static const GTypeInfo tinfo =

      {

        sizeof (AtkGObjectAccessibleClass),

        (GBaseInitFunc) NULL, /* base init */

        (GBaseFinalizeFunc) NULL, /* base finalize */

        (GClassInitFunc) atk_gobject_accessible_class_init,

        (GClassFinalizeFunc) NULL, /* class finalize */

        NULL, /* class data */

        sizeof (AtkGObjectAccessible),

        0, /* nb preallocs */

        (GInstanceInitFunc) NULL, /* instance init */

        NULL /* value table */

      };

      type = g_type_register_static (ATK_TYPE_OBJECT,

                                     "AtkGObjectAccessible", &tinfo, 0);

    }

  return type;

}

/**

 * atk_gobject_accessible_for_object:

 * @obj: a #GObject

 *

 * Gets the accessible object for the specified @obj.

 *

 * Returns: (transfer none): a #AtkObject which is the accessible object for

 * the @obj

 **/

AtkObject*

atk_gobject_accessible_for_object (GObject *obj)

{

  AtkObject* accessible;

  g_return_val_if_fail (G_IS_OBJECT (obj), NULL);

  /* See if we have a cached accessible for this object */

  accessible = quark_accessible_object ? g_object_get_qdata (obj, quark_accessible_object) : NULL;

  if (!accessible)

    {

      AtkObjectFactory *factory;

      AtkRegistry *default_registry;

      default_registry = atk_get_default_registry ();

      factory = atk_registry_get_factory (default_registry, 

                                          G_OBJECT_TYPE (obj));

      accessible = atk_object_factory_create_accessible (factory,

                                                         obj);

      if (!ATK_IS_GOBJECT_ACCESSIBLE (accessible))

        {

          /*

           * The AtkObject which was created was not a AtkGObjectAccessible

           */

          g_object_weak_ref (obj,

                             (GWeakNotify) g_object_unref,

                             accessible); 

          if (!quark_accessible_object)

            quark_accessible_object = g_quark_from_static_string ("accessible-object");

        }

      g_object_set_qdata (obj, quark_accessible_object, accessible);

    }

  return accessible;

}

/**

 * atk_gobject_accessible_get_object:

 * @obj: a #AtkGObjectAccessible

 *

 * Gets the GObject for which @obj is the accessible object.

 *

 * Returns: (transfer none): a #GObject which is the object for which @obj is

 * the accessible object

 **/

GObject *

atk_gobject_accessible_get_object (AtkGObjectAccessible *obj)

{

  g_return_val_if_fail (ATK_IS_GOBJECT_ACCESSIBLE (obj), NULL);

  return g_object_get_qdata (G_OBJECT (obj), quark_object);

}

static void

atk_real_gobject_accessible_initialize (AtkObject  *atk_obj,

                                        gpointer   data)

{

  AtkGObjectAccessible *atk_gobj;

  atk_gobj = ATK_GOBJECT_ACCESSIBLE (atk_obj);

  g_object_set_qdata (G_OBJECT (atk_gobj), quark_object, data);

  atk_obj->layer = ATK_LAYER_WIDGET;

  g_object_weak_ref (data,

                     (GWeakNotify) atk_gobject_accessible_object_gone_cb,

                     atk_gobj);

}

static void

atk_gobject_accessible_object_gone_cb (gpointer  data)

{

  GObject *object;

  g_return_if_fail (ATK_IS_GOBJECT_ACCESSIBLE (data));

  object = atk_gobject_accessible_get_object (data);

  if (object)

      g_object_set_qdata (object, quark_accessible_object, NULL);

  g_object_set_qdata (G_OBJECT (data), quark_object, NULL);

  atk_object_notify_state_change (ATK_OBJECT (data), ATK_STATE_DEFUNCT,

                                  TRUE); 

  g_object_unref (data);

}

static void

atk_gobject_accessible_dispose (GObject *atk_obj)

{

   GObject *obj = atk_gobject_accessible_get_object (ATK_GOBJECT_ACCESSIBLE (atk_obj));

   if (obj) {

      g_object_set_qdata (obj, quark_accessible_object, NULL);

      g_object_weak_unref (obj,

                           (GWeakNotify) atk_gobject_accessible_object_gone_cb,

                           atk_obj);

      g_object_set_qdata (atk_obj, quark_object, NULL);

      atk_object_notify_state_change (ATK_OBJECT (atk_obj), ATK_STATE_DEFUNCT,

                                      TRUE); 

   }

   G_OBJECT_CLASS (parent_class)->dispose (atk_obj);

}

static void

atk_gobject_accessible_class_init (AtkGObjectAccessibleClass *klass)

{ 

  AtkObjectClass *class;

  GObjectClass *object_class;

  class = ATK_OBJECT_CLASS (klass);

  parent_class = g_type_class_peek_parent (klass);

  class->initialize = atk_real_gobject_accessible_initialize;

  object_class = G_OBJECT_CLASS (klass);

  object_class->dispose = atk_gobject_accessible_dispose;

  if (!quark_accessible_object)

    quark_accessible_object = g_quark_from_static_string ("accessible-object");

  quark_object = g_quark_from_static_string ("object-for-accessible");

}