/* 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 <glib-object.h>

#include "gegl.h"
#include "gegl/gegl-debug.h"
#include "gegl-types-internal.h"
#include "gegl-operation-point-filter.h"
#include "graph/gegl-pad.h"
#include "graph/gegl-node.h"
#include "gegl-utils.h"
#include <string.h>

#include "gegl-buffer-private.h"
#include "gegl-tile-storage.h"

#include "opencl/gegl-cl.h"

static gboolean gegl_operation_point_filter_process
                              (GeglOperation       *operation,
                               GeglBuffer          *input,
                               GeglBuffer          *output,
                               const GeglRectangle *result,
                               gint                 level);

static gboolean gegl_operation_point_filter_op_process
                              (GeglOperation       *operation,
                               GeglOperationContext *context,
                               const gchar          *output_pad,
                               const GeglRectangle  *roi,
                               gint                  level);

G_DEFINE_TYPE (GeglOperationPointFilter, gegl_operation_point_filter, GEGL_TYPE_OPERATION_FILTER)

static void prepare (GeglOperation *operation)
{
  gegl_operation_set_format (operation, "input", babl_format ("RGBA float"));
  gegl_operation_set_format (operation, "output", babl_format ("RGBA float"));
}

static void
gegl_operation_point_filter_class_init (GeglOperationPointFilterClass *klass)
{
  GeglOperationClass *operation_class = GEGL_OPERATION_CLASS (klass);

  operation_class->process = gegl_operation_point_filter_op_process;
  operation_class->prepare = prepare;
  operation_class->no_cache = TRUE;

  klass->process = NULL;
  klass->cl_process = NULL;
}

static void
gegl_operation_point_filter_init (GeglOperationPointFilter *self)
{
}

static gboolean
gegl_operation_point_filter_cl_process (GeglOperation       *operation,
                                        GeglBuffer          *input,
                                        GeglBuffer          *output,
                                        const GeglRectangle *result,
                                        gint                 level)
{
  const Babl *in_format  = gegl_operation_get_format (operation, "input");
  const Babl *out_format = gegl_operation_get_format (operation, "output");

  GeglOperationPointFilterClass *point_filter_class = GEGL_OPERATION_POINT_FILTER_GET_CLASS (operation);

  gint j;
  cl_int cl_err = 0;
  gboolean err;

  /* non-texturizable format! */
  if (!gegl_cl_color_babl (in_format,  NULL) ||
      !gegl_cl_color_babl (out_format, NULL))
    {
      GEGL_NOTE (GEGL_DEBUG_OPENCL, "Non-texturizable format!");
      return FALSE;
    }

  GEGL_NOTE (GEGL_DEBUG_OPENCL, "BABL formats: (%s,%s) (%s,%s)\n \t Tile Size:(%d, %d)\n",
             babl_get_name(input->format),
             babl_get_name(in_format),
             babl_get_name(out_format),
             babl_get_name(output->format),
             input->tile_storage->tile_width,
             input->tile_storage->tile_height);

  /* Process */
  {
    GeglBufferClIterator *i = gegl_buffer_cl_iterator_new (output,   result, out_format, GEGL_CL_BUFFER_WRITE, GEGL_ABYSS_NONE);
                  gint read = gegl_buffer_cl_iterator_add (i, input, result, in_format,  GEGL_CL_BUFFER_READ, GEGL_ABYSS_NONE);
    while (gegl_buffer_cl_iterator_next (i, &err))
      {
        if (err) return FALSE;
        for (j=0; j < i->n; j++)
          {
            cl_err = point_filter_class->cl_process(operation, i->tex[read][j], i->tex[0][j],
                                                    i->size[0][j], &i->roi[0][j], level);
            if (cl_err != CL_SUCCESS)
              {
                GEGL_NOTE (GEGL_DEBUG_OPENCL, "Error in %s [GeglOperationPointFilter] Kernel",
                           GEGL_OPERATION_CLASS (operation)->name);
                return FALSE;
              }
          }
      }
  }
  return TRUE;
}

static gboolean
gegl_operation_point_filter_process (GeglOperation       *operation,
                                     GeglBuffer          *input,
                                     GeglBuffer          *output,
                                     const GeglRectangle *result,
                                     gint                 level)
{
  const Babl *in_format  = gegl_operation_get_format (operation, "input");
  const Babl *out_format = gegl_operation_get_format (operation, "output");
  GeglOperationPointFilterClass *point_filter_class;

  point_filter_class = GEGL_OPERATION_POINT_FILTER_GET_CLASS (operation);

  if ((result->width > 0) && (result->height > 0))
    {
      if (gegl_cl_is_accelerated () && point_filter_class->cl_process)
        {
          if (gegl_operation_point_filter_cl_process (operation, input, output, result, level))
            return TRUE;
        }

      {
        GeglBufferIterator *i = gegl_buffer_iterator_new (output, result, level, out_format, GEGL_BUFFER_WRITE, GEGL_ABYSS_NONE);
        gint read = /*output == input ? 0 :*/ gegl_buffer_iterator_add (i, input,  result, level, in_format, GEGL_BUFFER_READ, GEGL_ABYSS_NONE);
        /* using separate read and write iterators for in-place ideally a single
         * readwrite indice would be sufficient
         */
          while (gegl_buffer_iterator_next (i))
            point_filter_class->process (operation, i->data[read], i->data[0], i->length, &i->roi[0], level);
      }
    }
  return TRUE;
}

gboolean gegl_can_do_inplace_processing (GeglOperation       *operation,
                                         GeglBuffer          *input,
                                         const GeglRectangle *result);

gboolean gegl_can_do_inplace_processing (GeglOperation       *operation,
                                         GeglBuffer          *input,
                                         const GeglRectangle *result)
{
  if (!input ||
      GEGL_IS_CACHE (input))
    return FALSE;
  if (gegl_object_get_has_forked (input))
    return FALSE;

  if (input->format == gegl_operation_get_format (operation, "output") &&
      gegl_rectangle_contains (gegl_buffer_get_extent (input), result))
    return TRUE;
  return FALSE;
}


static gboolean gegl_operation_point_filter_op_process
                              (GeglOperation       *operation,
                               GeglOperationContext *context,
                               const gchar          *output_pad,
                               const GeglRectangle  *roi,
                               gint                  level)
{
  GeglBuffer               *input;
  GeglBuffer               *output;
  gboolean                  success = FALSE;

  input = gegl_operation_context_get_source (context, "input");

  if (gegl_can_do_inplace_processing (operation, input, roi))
    {
      output = g_object_ref (input);
      gegl_operation_context_take_object (context, "output", G_OBJECT (output));
    }
  else
    {
      output = gegl_operation_context_get_target (context, "output");
    }

  success = gegl_operation_point_filter_process (operation, input, output, roi, level);
  if (output == GEGL_BUFFER (operation->node->cache))
    gegl_cache_computed (operation->node->cache, roi);

  if (input != NULL)
    g_object_unref (input);
  return success;
}