/* This file is part of GEGL

 *

 * GEGL 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.

 *

 * GEGL 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 GEGL; if not, see <http://www.gnu.org/licenses/>.

 *

 * Copyright 2006 Øyvind Kolås

 */

#include "config.h"

#include <string.h>

#include <glib-object.h>

#include "gegl.h"

#include "gegl-types-internal.h"

#include "gegl-operation-source.h"

#include "graph/gegl-node.h"

#include "graph/gegl-pad.h"

enum

{

  PROP_0,

  PROP_OUTPUT,

  PROP_LAST

};

static void     get_property (GObject      *gobject,

                              guint         prop_id,

                              GValue       *value,

                              GParamSpec   *pspec);

static void     set_property (GObject      *gobject,

                              guint         prop_id,

                              const GValue *value,

                              GParamSpec   *pspec);

static gboolean gegl_operation_source_process

                             (GeglOperation        *operation,

                              GeglOperationContext *context,

                              const gchar          *output_prop,

                              const GeglRectangle  *result,

                              gint                  level);

static void     attach       (GeglOperation *operation);

G_DEFINE_TYPE (GeglOperationSource, gegl_operation_source, GEGL_TYPE_OPERATION)

static GeglRectangle get_bounding_box          (GeglOperation        *self);

static GeglRectangle get_required_for_output   (GeglOperation        *operation,

                                                 const gchar         *input_pad,

                                                 const GeglRectangle *roi);

static GeglRectangle  get_cached_region        (GeglOperation       *operation,

                                                 const GeglRectangle *roi);

static void

gegl_operation_source_class_init (GeglOperationSourceClass * klass)

{

  GObjectClass       *gobject_class   = G_OBJECT_CLASS (klass);

  GeglOperationClass *operation_class = GEGL_OPERATION_CLASS (klass);

  gobject_class->set_property = set_property;

  gobject_class->get_property = get_property;

  operation_class->process = gegl_operation_source_process;

  operation_class->attach  = attach;

  operation_class->get_cached_region = get_cached_region;

  operation_class->get_bounding_box  = get_bounding_box;

  operation_class->get_required_for_output = get_required_for_output;

  g_object_class_install_property (gobject_class, PROP_OUTPUT,

                                   g_param_spec_object ("output",

                                                        "Output",

                                                        "Output pad for generated image buffer.",

                                                        GEGL_TYPE_BUFFER,

                                                        G_PARAM_READABLE |

                                                        GEGL_PARAM_PAD_OUTPUT));

}

static void

gegl_operation_source_init (GeglOperationSource *self)

{

}

static void

attach (GeglOperation *self)

{

  GeglOperation *operation    = GEGL_OPERATION (self);

  GObjectClass  *object_class = G_OBJECT_GET_CLASS (self);

  gegl_operation_create_pad (operation,

                             g_object_class_find_property (object_class,

                                                           "output"));

}

static void

get_property (GObject    *object,

              guint       prop_id,

              GValue     *value,

              GParamSpec *pspec)

{

}

static void

set_property (GObject      *object,

              guint         prop_id,

              const GValue *value,

              GParamSpec   *pspec)

{

}

static gboolean

gegl_operation_source_process (GeglOperation        *operation,

                               GeglOperationContext *context,

                               const gchar          *output_prop,

                               const GeglRectangle  *result,

                               gint                  level)

{

  GeglOperationSourceClass *klass = GEGL_OPERATION_SOURCE_GET_CLASS (operation);

  GeglBuffer               *output;

  gboolean                  success;

  if (strcmp (output_prop, "output"))

    {

      g_warning ("requested processing of %s pad on a source operation", output_prop);

      return FALSE;

    }

  g_assert (klass->process);

  output = gegl_operation_context_get_target (context, "output");

  success = klass->process (operation, output, result, level);

  if (output == GEGL_BUFFER (operation->node->cache))

    gegl_cache_computed (operation->node->cache, result);

  return success;

}

static GeglRectangle

get_bounding_box (GeglOperation *self)

{

  GeglRectangle result = { 0, 0, 0, 0 };

  g_warning ("Gegl Source '%s' does not override %s()",

             G_OBJECT_CLASS_NAME (G_OBJECT_GET_CLASS (self)),

             G_STRFUNC);

  return result;

}

static GeglRectangle

get_required_for_output (GeglOperation        *operation,

                         const gchar         *input_pad,

                         const GeglRectangle *roi)

{

  return *roi;

}

static GeglRectangle

get_cached_region (GeglOperation       *operation,

                   const GeglRectangle *roi)

{

  return *roi;

}