/* The GIMP -- an image manipulation program
 * Copyright (C) 1995 Spencer Kimball and Peter Mattis
 *
 * gimpbrushpreview.c
 * Copyright (C) 2001 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 2 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, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

#include "config.h"

#include <gtk/gtk.h>

#include "widgets-types.h"

#include "base/temp-buf.h"

#include "core/gimpbrush.h"
#include "core/gimpbrushpipe.h"

#include "gimpbrushpreview.h"
#include "gimpdnd.h"


static void   gimp_brush_preview_class_init (GimpBrushPreviewClass *klass);
static void   gimp_brush_preview_init       (GimpBrushPreview      *preview);

static void        gimp_brush_preview_destroy             (GtkObject   *object);
static void        gimp_brush_preview_render              (GimpPreview *preview);
static GtkWidget * gimp_brush_preview_create_popup        (GimpPreview *preview);
static gboolean    gimp_brush_preview_needs_popup         (GimpPreview *preview);

static gboolean    gimp_brush_preview_render_timeout_func (GimpBrushPreview *preview);


static GimpPreviewClass *parent_class = NULL;


GType
gimp_brush_preview_get_type (void)
{
  static GType preview_type = 0;

  if (! preview_type)
    {
      static const GTypeInfo preview_info =
      {
        sizeof (GimpBrushPreviewClass),
        NULL,           /* base_init */
        NULL,           /* base_finalize */
        (GClassInitFunc) gimp_brush_preview_class_init,
        NULL,           /* class_finalize */
        NULL,           /* class_data */
        sizeof (GimpBrushPreview),
        0,              /* n_preallocs */
        (GInstanceInitFunc) gimp_brush_preview_init,
      };

      preview_type = g_type_register_static (GIMP_TYPE_PREVIEW,
                                             "GimpBrushPreview",
                                             &preview_info, 0);
    }
  
  return preview_type;
}

static void
gimp_brush_preview_class_init (GimpBrushPreviewClass *klass)
{
  GtkObjectClass   *object_class;
  GimpPreviewClass *preview_class;

  object_class  = GTK_OBJECT_CLASS (klass);
  preview_class = GIMP_PREVIEW_CLASS (klass);

  parent_class = g_type_class_peek_parent (klass);

  object_class->destroy         = gimp_brush_preview_destroy;

  preview_class->render         = gimp_brush_preview_render;
  preview_class->create_popup   = gimp_brush_preview_create_popup;
  preview_class->needs_popup    = gimp_brush_preview_needs_popup;
}

static void
gimp_brush_preview_init (GimpBrushPreview *brush_preview)
{
  brush_preview->pipe_timeout_id      = 0;
  brush_preview->pipe_animation_index = 0;
}

static void
gimp_brush_preview_destroy (GtkObject *object)
{
  GimpBrushPreview *brush_preview;

  brush_preview = GIMP_BRUSH_PREVIEW (object);

  if (brush_preview->pipe_timeout_id)
    {
      g_source_remove (brush_preview->pipe_timeout_id);

      brush_preview->pipe_timeout_id      = 0;
      brush_preview->pipe_animation_index = 0;
    }

  if (GTK_OBJECT_CLASS (parent_class)->destroy)
    GTK_OBJECT_CLASS (parent_class)->destroy (object);
}

#define indicator_width  7
#define indicator_height 7

#define WHT { 255, 255, 255 }
#define BLK {   0,   0,   0 }
#define RED { 255, 127, 127 }

static void
gimp_brush_preview_render (GimpPreview *preview)
{
  GimpBrushPreview *brush_preview;
  GimpBrush        *brush;
  TempBuf          *temp_buf;
  gint              width;
  gint              height;
  gint              brush_width;
  gint              brush_height;
  guchar           *buf;
  guchar           *b;
  gint              x, y;
  gint              offset_x;
  gint              offset_y;

  brush_preview = GIMP_BRUSH_PREVIEW (preview);

  if (brush_preview->pipe_timeout_id)
    {
      g_source_remove (brush_preview->pipe_timeout_id);

      brush_preview->pipe_timeout_id = 0;
    }

  brush        = GIMP_BRUSH (preview->viewable);
  brush_width  = brush->mask->width;
  brush_height = brush->mask->height;

  width  = preview->width;
  height = preview->height;

  temp_buf = gimp_viewable_get_new_preview (preview->viewable,
					    width,
					    height);

  if (preview->is_popup)
    {
      gimp_preview_render_and_flush (preview,
				     temp_buf,
				     -1);

      temp_buf_free (temp_buf);

      if (GIMP_IS_BRUSH_PIPE (brush))
	{
	  if (width  != brush_width  ||
	      height != brush_height)
	    {
	      g_warning ("%s(): non-fullsize pipe popups are not supported yet.",
			 G_GNUC_FUNCTION);
	      return;
	    }

	  brush_preview->pipe_animation_index  = 0;
	  brush_preview->pipe_timeout_id =
	    g_timeout_add (300,
			   (GSourceFunc) gimp_brush_preview_render_timeout_func,
			   brush_preview);
	}

      return;
    }

  buf = temp_buf_data (temp_buf);

  if (width < brush_width || height < brush_height)
    {
      static const guchar scale_indicator_bits[7][7][3] = 
      {
        { WHT, WHT, WHT, WHT, WHT, WHT, WHT },
        { WHT, WHT, WHT, BLK, WHT, WHT, WHT },
        { WHT, WHT, WHT, BLK, WHT, WHT, WHT },
        { WHT, BLK, BLK, BLK, BLK, BLK, WHT },
        { WHT, WHT, WHT, BLK, WHT, WHT, WHT },
        { WHT, WHT, WHT, BLK, WHT, WHT, WHT },
        { WHT, WHT, WHT, WHT, WHT, WHT, WHT }
      };

      static const guchar scale_pipe_indicator_bits[7][7][3] = 
      {
        { WHT, WHT, WHT, WHT, WHT, WHT, WHT },
        { WHT, WHT, WHT, BLK, WHT, WHT, RED },
        { WHT, WHT, WHT, BLK, WHT, RED, RED },
        { WHT, BLK, BLK, BLK, BLK, BLK, RED },
        { WHT, WHT, WHT, BLK, RED, RED, RED },
        { WHT, WHT, RED, BLK, RED, RED, RED },
        { WHT, RED, RED, RED, RED, RED, RED }
      };

      offset_x = width  - indicator_width;
      offset_y = height - indicator_height;

      b = buf + (offset_y * width + offset_x) * temp_buf->bytes;

      for (y = 0; y < indicator_height; y++)
        {
          for (x = 0; x < indicator_height; x++)
            {
              if (GIMP_IS_BRUSH_PIPE (brush))
                {
                  *b++ = scale_pipe_indicator_bits[y][x][0];
                  *b++ = scale_pipe_indicator_bits[y][x][1];
                  *b++ = scale_pipe_indicator_bits[y][x][2];
                }
              else
                {
                  *b++ = scale_indicator_bits[y][x][0];
                  *b++ = scale_indicator_bits[y][x][1];
                  *b++ = scale_indicator_bits[y][x][2];
                }
            }

          b += (width - indicator_width) * temp_buf->bytes;
        }
    }
  else if (GIMP_IS_BRUSH_PIPE (brush))
    {
      static const guchar pipe_indicator_bits[7][7][3] = 
      {
        { WHT, WHT, WHT, WHT, WHT, WHT, WHT },
        { WHT, WHT, WHT, WHT, WHT, WHT, RED },
        { WHT, WHT, WHT, WHT, WHT, RED, RED },
        { WHT, WHT, WHT, WHT, RED, RED, RED },
        { WHT, WHT, WHT, RED, RED, RED, RED },
        { WHT, WHT, RED, RED, RED, RED, RED },
        { WHT, RED, RED, RED, RED, RED, RED }
      };

      offset_x = width  - indicator_width;
      offset_y = height - indicator_height;

      b = buf + (offset_y * width + offset_x) * temp_buf->bytes;

      for (y = 0; y < indicator_height; y++)
        {
          for (x = 0; x < indicator_height; x++)
            {
              *b++ = pipe_indicator_bits[y][x][0];
              *b++ = pipe_indicator_bits[y][x][1];
              *b++ = pipe_indicator_bits[y][x][2];
            }

          b += (width - indicator_width) * temp_buf->bytes;
        }
    }

#undef indicator_width
#undef indicator_height

#undef WHT
#undef BLK
#undef RED

  gimp_preview_render_and_flush (preview,
				 temp_buf,
				 -1);

  temp_buf_free (temp_buf);
}

static GtkWidget *
gimp_brush_preview_create_popup (GimpPreview *preview)
{
  gint popup_width;
  gint popup_height;

  popup_width  = GIMP_BRUSH (preview->viewable)->mask->width;
  popup_height = GIMP_BRUSH (preview->viewable)->mask->height;

  return gimp_preview_new_full (preview->viewable,
				popup_width,
				popup_height,
				0,
				TRUE, FALSE, FALSE);
}

static gboolean
gimp_brush_preview_needs_popup (GimpPreview *preview)
{
  GimpBrush *brush;
  gint       brush_width;
  gint       brush_height;

  brush        = GIMP_BRUSH (preview->viewable);
  brush_width  = brush->mask->width;
  brush_height = brush->mask->height;

  if (GIMP_IS_BRUSH_PIPE (brush)    ||
      brush_width  > preview->width ||
      brush_height > preview->height)
    return TRUE;

  return FALSE;
}

static gboolean
gimp_brush_preview_render_timeout_func (GimpBrushPreview *brush_preview)
{
  GimpPreview   *preview;
  GimpBrushPipe *brush_pipe;
  GimpBrush     *brush;
  TempBuf       *temp_buf;
  gint           brush_width;
  gint           brush_height;

  preview = GIMP_PREVIEW (brush_preview);

  if (! preview->viewable)
    {
      brush_preview->pipe_timeout_id      = 0;
      brush_preview->pipe_animation_index = 0;

      return FALSE;
    }

  brush_pipe   = GIMP_BRUSH_PIPE (preview->viewable);
  brush_width  = brush->mask->width;
  brush_height = brush->mask->height;

  brush_preview->pipe_animation_index++;

  if (brush_preview->pipe_animation_index >= brush_pipe->nbrushes)
    brush_preview->pipe_animation_index = 0;

  brush = GIMP_BRUSH (brush_pipe->brushes[brush_preview->pipe_animation_index]);

  temp_buf = gimp_viewable_get_new_preview (GIMP_VIEWABLE (brush),
					    preview->width,
					    preview->height);

  gimp_preview_render_and_flush (preview,
				 temp_buf,
				 -1);

  temp_buf_free (temp_buf);

  return TRUE;
}
