/* This file is part of GEGL.
 *
 * 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 3 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/>.
 *
 * Copyright 2006,2007 Øyvind Kolås <pippin@gimp.org>
 */
#include "config.h"
#include <glib.h>
#include <glib-object.h>
#include <string.h>

#include "gegl-types.h"
#include "gegl-matrix.h"
#include "gegl-buffer-types.h"
#include "gegl-buffer-private.h"
#include "gegl-tile-handler.h"
#include "gegl-tile-handler-empty.h"
#include "gegl-tile-handler-cache.h"
#include "gegl-tile-backend.h"

G_DEFINE_TYPE (GeglTileHandlerEmpty, gegl_tile_handler_empty, GEGL_TYPE_TILE_HANDLER)

static void
finalize (GObject *object)
{
  GeglTileHandlerEmpty *empty = GEGL_TILE_HANDLER_EMPTY (object);

  if (empty->tile)
    gegl_tile_unref (empty->tile);

  G_OBJECT_CLASS (gegl_tile_handler_empty_parent_class)->finalize (object);
}


static GeglTile *
get_tile (GeglTileSource *gegl_tile_source,
          gint            x,
          gint            y,
          gint            z)
{
  GeglTileSource       *source = GEGL_TILE_HANDLER (gegl_tile_source)->source;
  GeglTileHandlerEmpty *empty  = GEGL_TILE_HANDLER_EMPTY (gegl_tile_source);
  GeglTile             *tile   = NULL;

  if (source)
    tile = gegl_tile_source_get_tile (source, x, y, z);
  if (tile != NULL)
    return tile;

  tile = gegl_tile_dup (empty->tile);
  tile->x = x;
  tile->y = y;
  tile->z = z;

  if (empty->cache)
    gegl_tile_handler_cache_insert (empty->cache, tile, x, y, z);

  return tile;
}

static gpointer
gegl_tile_handler_empty_command (GeglTileSource  *buffer,
                                 GeglTileCommand  command,
                                 gint             x,
                                 gint             y,
                                 gint             z,
                                 gpointer         data)
{
  if (command == GEGL_TILE_GET)
    return get_tile (buffer, x, y, z);
  return gegl_tile_handler_source_command (buffer, command, x, y, z, data);
}

static void
gegl_tile_handler_empty_class_init (GeglTileHandlerEmptyClass *klass)
{
  GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
  gobject_class->finalize     = finalize;
}

static void
gegl_tile_handler_empty_init (GeglTileHandlerEmpty *self)
{
  ((GeglTileSource*)self)->command = gegl_tile_handler_empty_command;
}

GeglTileHandler *
gegl_tile_handler_empty_new (GeglTileBackend      *backend,
                             GeglTileHandlerCache *cache)
{
  GeglTileHandlerEmpty *empty = g_object_new (GEGL_TYPE_TILE_HANDLER_EMPTY, NULL);
  gint tile_size = gegl_tile_backend_get_tile_size (backend);
  empty->backend = backend;
  empty->cache = cache;
  empty->tile = gegl_tile_new (tile_size);
  memset (gegl_tile_get_data (empty->tile), 0x00, tile_size);
  return (void*)empty;
}