/* This file is an image processing operation for 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 <pippin@gimp.org>

 */

/* FIXME: need to make this OpenRaster inspired layer integrate better

 * with the newer caching system

 */

#include "config.h"

#include <glib/gi18n-lib.h>

#ifdef GEGL_CHANT_PROPERTIES

gegl_chant_string(composite_op, _("Operation"), "gegl:over",

                  _("Composite operation to use"))

gegl_chant_double(opacity, _("Opacity"), 0.0, 1.0, 1.0,

                  _("Opacity"))

gegl_chant_double(x, _("X"), -G_MAXDOUBLE, G_MAXDOUBLE, 0.0,

                  _("Horizontal position"))

gegl_chant_double(y, _("Y"), -G_MAXDOUBLE, G_MAXDOUBLE, 0.0,

                  _("Vertical position"))

gegl_chant_double(scale, _("Scale"), -G_MAXDOUBLE, G_MAXDOUBLE, 1.0,

                  _("Scale 1:1 size"))

gegl_chant_file_path(src, _("Source"), "",

                _("Source datafile (png, jpg, raw, svg, bmp, tif, ...)"))

#else

#include <gegl-plugin.h>

struct _GeglChant

{

  GeglOperationMeta parent_instance;

  gpointer          properties;

  GeglNode *self;

  GeglNode *input;

  GeglNode *aux;

  GeglNode *output;

  GeglNode *composite_op;

  GeglNode *translate;

  GeglNode *opacity;

  GeglNode *scale;

  GeglNode *load;

  gchar *cached_path;

  gdouble p_opacity;

  gdouble p_scale;

  gdouble p_x;

  gdouble p_y;

  gchar  *p_composite_op;

};

typedef struct

{

  GeglOperationMetaClass parent_class;

} GeglChantClass;

#define GEGL_CHANT_C_FILE "layer.c"

#include "gegl-chant.h"

GEGL_DEFINE_DYNAMIC_OPERATION(GEGL_TYPE_OPERATION_META)

#include <glib/gprintf.h>

static void

prepare (GeglOperation *operation)

{

  GeglChantO *o = GEGL_CHANT_PROPERTIES (operation);

  GeglChant *self = GEGL_CHANT (operation);

  /* If the src is NULL, and we previously used a source, clear what we have

   * cached and directly link the input and output. We don't need a composite

   * operation if we don't have a source, so don't continue preparing.

   */

  if (o->src[0] == 0)

    {

      if (self->cached_path != NULL)

        {

          gegl_node_link (self->input, self->output);

          g_free(self->cached_path);

          self->cached_path = NULL;

        }

      return;

    }

  /* warning: this might trigger regeneration of the graph,

   *          for now this is evaded by just ignoring additional

   *          requests to be made into members of the graph

   */

  /* Check if the composite operation we're using has changed from that which

   * is already in use.

   */

  if (!self->p_composite_op || strcmp (self->p_composite_op, o->composite_op))

    {

      gegl_node_set (self->composite_op,

                     "operation", o->composite_op,

                     NULL);

      if (self->p_composite_op)

        g_free (self->p_composite_op);

      self->p_composite_op = g_strdup (o->composite_op);

    }

  g_assert(o->src && o->src[0]);

  /* Load a src image, and relink the input/composite/output chain, as it

   * will currently be set to an input/output chain without a composite

   * source.

   */

  /* FIXME:

   * this reimplements the "load" op, which shouldn't be neccesary, but

   * currently seems to be neccesary since GEGL doesn't like a meta-op

   * to be implemented using another meta-op.

   */

  if (self->cached_path == NULL || strcmp (o->src, self->cached_path))

    {

      const gchar *extension = strrchr (o->src, '.');

      const gchar *handler = NULL;

      if (!g_file_test (o->src, G_FILE_TEST_EXISTS))

      {

        gchar *name = g_filename_display_name (o->src);

        gchar *tmp  = g_strdup_printf ("File '%s' does not exist", name);

        g_free (name);

        g_warning ("load: %s", tmp);

        gegl_node_set (self->load,

            "operation", "gegl:text",

            "size", 12.0,

            "string", tmp,

            NULL);

        g_free (tmp);

      }

      else

      {

        if (extension)

          handler = gegl_extension_handler_get (extension);

        gegl_node_set (self->load,

            "operation", handler,

            NULL);

        gegl_node_set (self->load,

            "path",  o->src,

            NULL);

      }

      /* Currently not using the composite op, reinsert it */

      if (!self->cached_path)

        gegl_node_link_many (self->input, self->composite_op, self->output, NULL);

      if (self->cached_path)

        g_free (self->cached_path);

      self->cached_path = g_strdup (o->src);

    }

  if (o->scale != self->p_scale)

    {

      gegl_node_set (self->scale,

                     "x",  o->scale,

                     "y",  o->scale,

                     NULL);

      self->p_scale= o->scale;

    }

  if (o->opacity != self->p_opacity)

    {

      gegl_node_set (self->opacity,

                     "value",  o->opacity,

                     NULL);

      self->p_opacity = o->opacity;

    }

  if (o->x != self->p_x ||

      o->y != self->p_y)

    {

      gegl_node_set (self->translate,

                     "x",  o->x,

                     "y",  o->y,

                     NULL);

      self->p_x = o->x;

      self->p_y = o->y;

    }

}

static void attach (GeglOperation *operation)

{

  GeglChant  *self = GEGL_CHANT (operation);

  GeglChantO *o    = GEGL_CHANT_PROPERTIES (operation);

  GeglNode *gegl;

  self->self = GEGL_OPERATION (self)->node;

  gegl = self->self;

  self->input = gegl_node_get_input_proxy (gegl, "input");

  self->aux = gegl_node_get_input_proxy (gegl, "aux");

  self->output = gegl_node_get_output_proxy (gegl, "output");

  self->composite_op = gegl_node_new_child (gegl,

                                         "operation", o->composite_op,

                                         NULL);

  self->translate = gegl_node_new_child (gegl, "operation", "gegl:translate", NULL);

  self->scale = gegl_node_new_child (gegl, "operation", "gegl:scale", NULL);

  self->opacity = gegl_node_new_child (gegl, "operation", "gegl:opacity", NULL);

  self->load = gegl_node_new_child (gegl,

                                    "operation", "gegl:text",

                                    "string", "Load operation placeholder",

                                    NULL);

  gegl_node_link_many (self->load, self->scale, self->opacity, self->translate,

                       NULL);

  gegl_node_link_many (self->input, self->composite_op, self->output, NULL);

  gegl_node_connect_from (self->composite_op, "aux", self->translate, "output");

}

static void

finalize (GObject *object)

{

  GeglChant *self = GEGL_CHANT (object);

  if (self->cached_path)

    g_free (self->cached_path);

  if (self->p_composite_op)

    g_free (self->p_composite_op);

  G_OBJECT_CLASS (gegl_chant_parent_class)->finalize (object);

}

static void

gegl_chant_class_init (GeglChantClass *klass)

{

  GObjectClass       *object_class;

  GeglOperationClass *operation_class;

  object_class    = G_OBJECT_CLASS (klass);

  operation_class = GEGL_OPERATION_CLASS (klass);

  object_class->finalize = finalize;

  operation_class->attach = attach;

  operation_class->prepare = prepare;

  gegl_operation_class_set_keys (operation_class,

    "name"       , "gegl:layer",

    "categories" , "meta",

    "description", _("A layer in the traditional sense"),

    NULL);

}

#endif