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

#include "config.h"

#include <glib-object.h>

#include "paint-types.h"

#include "gimppaintcore.h"
#include "gimppaintcoreundo.h"


enum
{
  PROP_0,
  PROP_PAINT_CORE
};


static GObject * gimp_paint_core_undo_constructor  (GType                  type,
                                                    guint                  n_params,
                                                    GObjectConstructParam *params);
static void      gimp_paint_core_undo_set_property (GObject               *object,
                                                    guint                  property_id,
                                                    const GValue          *value,
                                                    GParamSpec            *pspec);
static void      gimp_paint_core_undo_get_property (GObject               *object,
                                                    guint                  property_id,
                                                    GValue                *value,
                                                    GParamSpec            *pspec);

static void      gimp_paint_core_undo_pop          (GimpUndo              *undo,
                                                    GimpUndoMode           undo_mode,
                                                    GimpUndoAccumulator   *accum);
static void      gimp_paint_core_undo_free         (GimpUndo              *undo,
                                                    GimpUndoMode           undo_mode);


G_DEFINE_TYPE (GimpPaintCoreUndo, gimp_paint_core_undo, GIMP_TYPE_UNDO)

#define parent_class gimp_paint_core_undo_parent_class


static void
gimp_paint_core_undo_class_init (GimpPaintCoreUndoClass *klass)
{
  GObjectClass  *object_class = G_OBJECT_CLASS (klass);
  GimpUndoClass *undo_class   = GIMP_UNDO_CLASS (klass);

  object_class->constructor  = gimp_paint_core_undo_constructor;
  object_class->set_property = gimp_paint_core_undo_set_property;
  object_class->get_property = gimp_paint_core_undo_get_property;

  undo_class->pop            = gimp_paint_core_undo_pop;
  undo_class->free           = gimp_paint_core_undo_free;

  g_object_class_install_property (object_class, PROP_PAINT_CORE,
                                   g_param_spec_object ("paint-core", NULL, NULL,
                                                        GIMP_TYPE_PAINT_CORE,
                                                        GIMP_PARAM_READWRITE |
                                                        G_PARAM_CONSTRUCT_ONLY));
}

static void
gimp_paint_core_undo_init (GimpPaintCoreUndo *undo)
{
}

static GObject *
gimp_paint_core_undo_constructor (GType                  type,
                                  guint                  n_params,
                                  GObjectConstructParam *params)
{
  GObject           *object;
  GimpPaintCoreUndo *paint_core_undo;

  object = G_OBJECT_CLASS (parent_class)->constructor (type, n_params, params);

  paint_core_undo = GIMP_PAINT_CORE_UNDO (object);

  g_assert (GIMP_IS_PAINT_CORE (paint_core_undo->paint_core));

  paint_core_undo->last_coords = paint_core_undo->paint_core->start_coords;

  g_object_add_weak_pointer (G_OBJECT (paint_core_undo->paint_core),
                             (gpointer) &paint_core_undo->paint_core);

  return object;
}

static void
gimp_paint_core_undo_set_property (GObject      *object,
                                   guint         property_id,
                                   const GValue *value,
                                   GParamSpec   *pspec)
{
  GimpPaintCoreUndo *paint_core_undo = GIMP_PAINT_CORE_UNDO (object);

  switch (property_id)
    {
    case PROP_PAINT_CORE:
      paint_core_undo->paint_core = g_value_get_object (value);
      break;

    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
      break;
    }
}

static void
gimp_paint_core_undo_get_property (GObject    *object,
                                   guint       property_id,
                                   GValue     *value,
                                   GParamSpec *pspec)
{
  GimpPaintCoreUndo *paint_core_undo = GIMP_PAINT_CORE_UNDO (object);

  switch (property_id)
    {
    case PROP_PAINT_CORE:
      g_value_set_object (value, paint_core_undo->paint_core);
      break;

    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
      break;
    }
}

static void
gimp_paint_core_undo_pop (GimpUndo              *undo,
                          GimpUndoMode           undo_mode,
                          GimpUndoAccumulator   *accum)
{
  GimpPaintCoreUndo *paint_core_undo = GIMP_PAINT_CORE_UNDO (undo);

  GIMP_UNDO_CLASS (parent_class)->pop (undo, undo_mode, accum);

  /*  only pop if the core still exists  */
  if (paint_core_undo->paint_core)
    {
      GimpCoords tmp_coords;

      tmp_coords = paint_core_undo->paint_core->last_coords;
      paint_core_undo->paint_core->last_coords = paint_core_undo->last_coords;
      paint_core_undo->last_coords = tmp_coords;
    }
}

static void
gimp_paint_core_undo_free (GimpUndo     *undo,
                           GimpUndoMode  undo_mode)
{
  GimpPaintCoreUndo *paint_core_undo = GIMP_PAINT_CORE_UNDO (undo);

  if (paint_core_undo->paint_core)
    {
      g_object_remove_weak_pointer (G_OBJECT (paint_core_undo->paint_core),
                                    (gpointer) &paint_core_undo->paint_core);
      paint_core_undo->paint_core = NULL;
    }

  GIMP_UNDO_CLASS (parent_class)->free (undo, undo_mode);
}