/* GIMP - The GNU Image Manipulation Program
 * Copyright (C) 1995 Spencer Kimball and Peter Mattis
 *
 * gimp-gegl-nodes.h
 * Copyright (C) 2012 Michael Natterer <mitch@gimp.org>
 *
 * 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 3 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, see <http://www.gnu.org/licenses/>.
 */

#include "config.h"

#include <gegl.h>

#include "gimp-gegl-types.h"

#include "gimp-gegl-nodes.h"
#include "gimp-gegl-utils.h"


GeglNode *
gimp_gegl_create_flatten_node (const GimpRGB *background)
{
  GeglNode  *node;
  GeglNode  *input;
  GeglNode  *output;
  GeglNode  *color;
  GeglNode  *over;
  GeglColor *c;

  g_return_val_if_fail (background != NULL, NULL);

  node = gegl_node_new ();

  input  = gegl_node_get_input_proxy  (node, "input");
  output = gegl_node_get_output_proxy (node, "output");

  c = gimp_gegl_color_new (background);
  color = gegl_node_new_child (node,
                               "operation", "gegl:color",
                               "value",     c,
                               NULL);
  g_object_unref (c);

  over = gegl_node_new_child (node,
                              "operation", "gegl:over",
                              NULL);

  gegl_node_connect_to (input,  "output",
                        over,   "aux");
  gegl_node_connect_to (color,  "output",
                        over,   "input");
  gegl_node_connect_to (over,   "output",
                        output, "input");

  return node;
}

GeglNode *
gimp_gegl_create_apply_opacity_node (GeglBuffer *mask,
                                     gint        mask_offset_x,
                                     gint        mask_offset_y,
                                     gdouble     opacity)
{
  GeglNode  *node;
  GeglNode  *input;
  GeglNode  *output;
  GeglNode  *opacity_node;
  GeglNode  *mask_source;

  g_return_val_if_fail (GEGL_IS_BUFFER (mask), NULL);

  node = gegl_node_new ();

  input  = gegl_node_get_input_proxy  (node, "input");
  output = gegl_node_get_output_proxy (node, "output");

  opacity_node = gegl_node_new_child (node,
                                      "operation", "gegl:opacity",
                                      "value",     opacity,
                                      NULL);

  mask_source = gimp_gegl_add_buffer_source (node, mask,
                                             mask_offset_x,
                                             mask_offset_y);

  gegl_node_connect_to (input,        "output",
                        opacity_node, "input");
  gegl_node_connect_to (mask_source,  "output",
                        opacity_node, "aux");
  gegl_node_connect_to (opacity_node, "output",
                        output,       "input");

  return node;
}

GeglNode *
gimp_gegl_create_apply_buffer_node (GeglBuffer           *buffer,
                                    gint                  buffer_offset_x,
                                    gint                  buffer_offset_y,
                                    gint                  src_offset_x,
                                    gint                  src_offset_y,
                                    gint                  dest_offset_x,
                                    gint                  dest_offset_y,
                                    GeglBuffer           *mask,
                                    gint                  mask_offset_x,
                                    gint                  mask_offset_y,
                                    gdouble               opacity,
                                    GimpLayerModeEffects  mode,
                                    GimpComponentMask     affect)

{
  GeglNode *node;
  GeglNode *input;
  GeglNode *output;
  GeglNode *buffer_source;
  GeglNode *mask_source;
  GeglNode *mode_node;

  g_return_val_if_fail (GEGL_IS_BUFFER (buffer), NULL);
  g_return_val_if_fail (mask == NULL || GEGL_IS_BUFFER (mask), NULL);

  node = gegl_node_new ();

  input = gegl_node_get_input_proxy (node, "input");

  if (src_offset_x != 0 || src_offset_y != 0)
    {
      GeglNode *translate =
        gegl_node_new_child (node,
                             "operation", "gegl:translate",
                             "x",         (gdouble) src_offset_x,
                             "y",         (gdouble) src_offset_y,
                             NULL);

      gegl_node_connect_to (input,     "output",
                            translate, "input");

      input = translate;
    }

  output = gegl_node_get_output_proxy (node, "output");

  if (dest_offset_x != 0 || dest_offset_y != 0)
    {
      GeglNode *translate =
        gegl_node_new_child (node,
                             "operation", "gegl:translate",
                             "x",         (gdouble) dest_offset_x,
                             "y",         (gdouble) dest_offset_y,
                             NULL);

      gegl_node_connect_to (translate, "output",
                            output,    "input");

      output = translate;
    }

  if (affect == 0)
    {
      /*  nothing to do, pass through  */

      gegl_node_connect_to (input,  "output",
                            output, "input");

      return node;
    }

  buffer_source = gimp_gegl_add_buffer_source (node, buffer,
                                               buffer_offset_x,
                                               buffer_offset_y);


  if (mask)
    mask_source = gimp_gegl_add_buffer_source (node, mask,
                                               mask_offset_x,
                                               mask_offset_y);
  else
    mask_source = NULL;

  mode_node = gegl_node_new_child (node,
                                   "operation", "gegl:over",
                                   NULL);
  gimp_gegl_node_set_layer_mode (mode_node, mode, FALSE);

  if (mode == GIMP_REPLACE_MODE)
    {
      /*  modes that need access to the buffer's alpha channel are
       *  implemented using GeglOperationPointComposer3 subclasses,
       *  and have an "opacity" property, so they have access to all
       *  sources of transparency independently
       */

      gegl_node_set (mode_node,
                     "opacity", opacity,
                     NULL);

      gegl_node_connect_to (buffer_source, "output",
                            mode_node,     "aux");

      if (mask_source)
        gegl_node_connect_to (mask_source, "output",
                              mode_node,   "aux2");
    }
  else if (mask_source || opacity < 1.0)
    {
      /*  normal case: put the buffer through an opacity node that
       *  applies mask and opacity before doing the actual mode
       */

      GeglNode *opacity_node;

      opacity_node = gegl_node_new_child (node,
                                          "operation", "gegl:opacity",
                                          "value",     opacity,
                                          NULL);

      gegl_node_connect_to (buffer_source, "output",
                            opacity_node,  "input");

      if (mask_source)
        gegl_node_connect_to (mask_source,   "output",
                              opacity_node,  "aux");

      gegl_node_connect_to (opacity_node, "output",
                            mode_node,    "aux");
    }
  else
    {
      /*  shortcut for the case where the opacity node wouldn't do
       *  anything
       */

      gegl_node_connect_to (buffer_source, "output",
                            mode_node,     "aux");
    }

  gegl_node_connect_to (input,     "output",
                        mode_node, "input");

  if (affect == GIMP_COMPONENT_ALL)
    {
      gegl_node_connect_to (mode_node, "output",
                            output,    "input");
    }
  else
    {
      GeglNode *affect_node;

      affect_node = gegl_node_new_child (node,
                                         "operation", "gimp:mask-components",
                                         "mask",      affect,
                                         NULL);

      gegl_node_connect_to (input,       "output",
                            affect_node, "input");
      gegl_node_connect_to (mode_node,   "output",
                            affect_node, "aux");
      gegl_node_connect_to (affect_node, "output",
                            output,      "input");
    }

  return node;
}

GeglNode *
gimp_gegl_add_buffer_source (GeglNode   *parent,
                             GeglBuffer *buffer,
                             gint        offset_x,
                             gint        offset_y)
{
  GeglNode *buffer_source;

  g_return_val_if_fail (GEGL_IS_NODE (parent), NULL);
  g_return_val_if_fail (GEGL_IS_BUFFER (buffer), NULL);

  buffer_source = gegl_node_new_child (parent,
                                       "operation", "gegl:buffer-source",
                                       "buffer",    buffer,
                                       NULL);

  if (offset_x != 0 || offset_y != 0)
    {
      GeglNode *translate =
        gegl_node_new_child (parent,
                             "operation", "gegl:translate",
                             "x",         (gdouble) offset_x,
                             "y",         (gdouble) offset_y,
                             NULL);

      gegl_node_connect_to (buffer_source, "output",
                            translate,     "input");

      buffer_source = translate;
    }

  return buffer_source;
}

void
gimp_gegl_node_set_layer_mode (GeglNode             *node,
                               GimpLayerModeEffects  mode,
                               gboolean              premultiplied)
{
  const gchar *operation = "gimp:normal-mode";

  g_return_if_fail (GEGL_IS_NODE (node));

  switch (mode)
    {
    case GIMP_BEHIND_MODE:
    case GIMP_HUE_MODE:
    case GIMP_SATURATION_MODE:
    case GIMP_COLOR_MODE:
    case GIMP_VALUE_MODE:
    case GIMP_COLOR_ERASE_MODE:
    case GIMP_ANTI_ERASE_MODE:
      gegl_node_set (node,
                     "operation",     "gimp:point-layer-mode",
                     "blend-mode",    mode,
                     "premultiplied", premultiplied,
                     NULL);
      return;

    default:
      break;
    }

  switch (mode)
    {
    case GIMP_NORMAL_MODE:        operation = "gimp:normal-mode"; break;
    case GIMP_DISSOLVE_MODE:      operation = "gimp:dissolve-mode"; break;
    case GIMP_BEHIND_MODE:        operation = "gimp:behind-mode"; break;
    case GIMP_MULTIPLY_MODE:      operation = "gimp:multiply-mode"; break;
    case GIMP_SCREEN_MODE:        operation = "gimp:screen-mode"; break;
    case GIMP_OVERLAY_MODE:       operation = "gimp:overlay-mode"; break;
    case GIMP_DIFFERENCE_MODE:    operation = "gimp:difference-mode"; break;
    case GIMP_ADDITION_MODE:      operation = "gimp:addition-mode"; break;
    case GIMP_SUBTRACT_MODE:      operation = "gimp:subtract-mode"; break;
    case GIMP_DARKEN_ONLY_MODE:   operation = "gimp:darken-only-mode"; break;
    case GIMP_LIGHTEN_ONLY_MODE:  operation = "gimp:lighten-only-mode"; break;
    case GIMP_HUE_MODE:           operation = "gimp:hue-mode"; break;
    case GIMP_SATURATION_MODE:    operation = "gimp:saturation-mode"; break;
    case GIMP_COLOR_MODE:         operation = "gimp:color-mode"; break;
    case GIMP_VALUE_MODE:         operation = "gimp:value-mode"; break;
    case GIMP_DIVIDE_MODE:        operation = "gimp:divide-mode"; break;
    case GIMP_DODGE_MODE:         operation = "gimp:dodge-mode"; break;
    case GIMP_BURN_MODE:          operation = "gimp:burn-mode"; break;
    case GIMP_HARDLIGHT_MODE:     operation = "gimp:hardlight-mode"; break;
    case GIMP_SOFTLIGHT_MODE:     operation = "gimp:softlight-mode"; break;
    case GIMP_GRAIN_EXTRACT_MODE: operation = "gimp:grain-extract-mode"; break;
    case GIMP_GRAIN_MERGE_MODE:   operation = "gimp:grain-merge-mode"; break;
    case GIMP_COLOR_ERASE_MODE:   operation = "gimp:color-erase-mode"; break;
    case GIMP_ERASE_MODE:         operation = "gimp:erase-mode"; break;
    case GIMP_REPLACE_MODE:       operation = "gimp:replace-mode"; break;
    case GIMP_ANTI_ERASE_MODE:    operation = "gimp:anti-erase-mode"; break;
    default:
      break;
    }

  gegl_node_set (node,
                 "operation",     operation,
                 "premultiplied", premultiplied,
                 NULL);
}

void
gimp_gegl_node_set_matrix (GeglNode          *node,
                           const GimpMatrix3 *matrix)
{
  gchar *matrix_string;

  g_return_if_fail (GEGL_IS_NODE (node));
  g_return_if_fail (matrix != NULL);

  matrix_string = gegl_matrix3_to_string ((GeglMatrix3 *) matrix);

  gegl_node_set (node,
                 "transform", matrix_string,
                 NULL);

  g_free (matrix_string);
}
