/*
 * Copyright (C) 1995 Spencer Kimball and Peter Mattis
 *
 * This is a plug-in for the GIMP.
 *
 * Colormap-Rotation plug-in. Exchanges two color ranges.
 *
 * Copyright (C) 1999 Sven Anders (anderss@fmi.uni-passau.de)
 *                    Based on code from Pavel Grinfeld (pavel@ml.com)
 *
 *
 * 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.
 */

/*-----------------------------------------------------------------------------------
 * Change log:
 * 
 * Version 2.0, 04 April 1999.
 *  Nearly complete rewrite, made plug-in stable.
 *  (Works with GIMP 1.1 and GTK+ 1.2)
 *
 * Version 1.0, 27 March 1997.
 *  Initial (unstable) release by Pavel Grinfeld
 *
 *-----------------------------------------------------------------------------------*/

#include <stdio.h>
#include <stdlib.h>
#include <math.h>

#include "config.h"
#include <gtk/gtk.h>
#include "libgimp/gimp.h"
#include "libgimp/stdplugins-intl.h"

#include "rcm.h"
#include "rcm_misc.h"
#include "rcm_dialog.h"
#include "rcm_callback.h"

/*-----------------------------------------------------------------------------------*/
/* Forward declarations */
/*-----------------------------------------------------------------------------------*/

void query (void);
void run   (char *name, int nparams, GimpParam *param, int *nreturn_vals, GimpParam **return_vals);

/*-----------------------------------------------------------------------------------*/
/* Global variables */
/*-----------------------------------------------------------------------------------*/

RcmParams Current =
{
  SELECTION,           /* SELECTION ONLY */
  TRUE,                /* REAL TIME */
  FALSE,               /* SUCCESS */
  RADIANS_OVER_PI,     /* START IN RADIANS OVER PI */
  GRAY_TO
};

/*-----------------------------------------------------------------------------------*/
/* Local variables */
/*-----------------------------------------------------------------------------------*/

GimpPlugInInfo PLUG_IN_INFO =
{
  NULL,    /* init_proc */
  NULL,    /* quit_proc */
  query,   /* query_proc */
  run,     /* run_proc */
};

/*-----------------------------------------------------------------------------------*/
/* Dummy function */
/*-----------------------------------------------------------------------------------*/

MAIN()

/*-----------------------------------------------------------------------------------*/
/* Query plug-in */
/*-----------------------------------------------------------------------------------*/

void 
query (void)
{
  GimpParamDef args[] =
  {
    { GIMP_PDB_INT32, "run_mode", "Interactive, non-interactive" },
    { GIMP_PDB_IMAGE, "image", "Input image (used for indexed images)" },
    { GIMP_PDB_DRAWABLE, "drawable", "Input drawable" },
  };

  gimp_install_procedure ("plug_in_rotate_colormap",
			  "Colormap rotation as in xv",
			  "Exchanges two color ranges. "
                          "Based on code from Pavel Grinfeld (pavel@ml.com). "
                          "This version written by Sven Anders (anderss@fmi.uni-passau.de).",
			  "Sven Anders (anderss@fmi.uni-passau.de) and Pavel Grinfeld (pavel@ml.com)",
			  "Sven Anders (anderss@fmi.uni-passau.de)",
			  "04th April 1999",
			  N_("<Image>/Filters/Colors/Map/Colormap Rotation..."),
			  "RGB*",
			  GIMP_PLUGIN,
			  G_N_ELEMENTS (args), 0,
			  args, NULL);
}

/*-----------------------------------------------------------------------------------*/
/* Rotate colormap of a single row */
/*-----------------------------------------------------------------------------------*/

void 
rcm_row (const guchar *src_row, 
	 guchar       *dest_row,
	 gint          row, 
	 gint          row_width, 
	 gint          bytes)
{
  gint col, bytenum, skip;
  gdouble H,S,V;
  guchar rgb[3];
  
  for (col=0; col < row_width; col++)
  {
    skip = 0;
      
    rgb[0] = src_row[col*bytes + 0];
    rgb[1] = src_row[col*bytes + 1];
    rgb[2] = src_row[col*bytes + 2];
      
    gimp_rgb_to_hsv4 (rgb, &H, &S, &V);
      
    if (rcm_is_gray(S))
    {
      if (Current.Gray_to_from == GRAY_FROM)
      {
	if (rcm_angle_inside_slice(Current.Gray->hue,Current.From->angle) <= 1)
	{
	  H = Current.Gray->hue / TP;
	  S = Current.Gray->satur;
	}
	else 
	{
	  skip = 1;
	}
      }
      else
      {
	skip = 1;
	gimp_hsv_to_rgb4 (rgb, Current.Gray->hue/TP, Current.Gray->satur, V);
      }
    }
      
    if (!skip)
    {
      H = rcm_linear(rcm_left_end(Current.From->angle),
		     rcm_right_end(Current.From->angle),
		     rcm_left_end(Current.To->angle),
		     rcm_right_end(Current.To->angle),
		     H*TP);    

      H = angle_mod_2PI(H) / TP;
      gimp_hsv_to_rgb4 (rgb, H, S, V);
    }
      
    dest_row[col * bytes + 0] = rgb[0];
    dest_row[col * bytes + 1] = rgb[1];
    dest_row[col * bytes + 2] = rgb[2];
      
    if (bytes > 3)
    {
      for (bytenum=3; bytenum<bytes; bytenum++)
	dest_row[col*bytes+bytenum] = src_row[col*bytes+bytenum];
    }
  }
}

/*-----------------------------------------------------------------------------------*/
/* Rotate colormap row by row ... */
/*-----------------------------------------------------------------------------------*/

void 
rcm (GimpDrawable *drawable)
{
  GimpPixelRgn srcPR, destPR;
  gint width, height;
  gint bytes;
  guchar *src_row, *dest_row;
  gint row;
  gint x1, y1, x2, y2;
  
  gimp_drawable_mask_bounds (drawable->drawable_id, &x1, &y1, &x2, &y2);

  width = drawable->width;
  height = drawable->height;
  bytes = drawable->bpp;

  src_row = (guchar *) malloc ((x2 - x1) * bytes);
  dest_row = (guchar *) malloc ((x2 - x1) * bytes);

  gimp_pixel_rgn_init(&srcPR, drawable, 0, 0, width, height, FALSE, FALSE);
  gimp_pixel_rgn_init(&destPR, drawable, 0, 0, width, height, TRUE, TRUE);

  for (row=y1; row < y2; row++)
  {
    gimp_pixel_rgn_get_row(&srcPR, src_row, x1, row, (x2 - x1));

    rcm_row(src_row, dest_row, row, (x2 - x1), bytes);
      
    gimp_pixel_rgn_set_row(&destPR, dest_row, x1, row, (x2 - x1));
      
    if ((row % 10) == 0)
      gimp_progress_update((double) row / (double) (y2 - y1));
  }

  /*  update the processed region  */

  gimp_drawable_flush(drawable);
  gimp_drawable_merge_shadow(drawable->drawable_id, TRUE);
  gimp_drawable_update(drawable->drawable_id, x1, y1, (x2 - x1), (y2 - y1));
  
  free (src_row);
  free (dest_row);
}

/*-----------------------------------------------------------------------------------*/
/* STANDARD RUN */
/*-----------------------------------------------------------------------------------*/

void 
run (char    *name, 
     int      nparams, 
     GimpParam  *param, 
     int     *nreturn_vals, 
     GimpParam **return_vals)
{
  GimpParam values[1];
  GimpPDBStatusType status = GIMP_PDB_SUCCESS;
  
  *nreturn_vals = 1;
  *return_vals = values;

  values[0].type = GIMP_PDB_STATUS;
  values[0].data.d_status = status;

  Current.drawable = gimp_drawable_get(param[2].data.d_drawable);
  Current.mask = gimp_drawable_get(gimp_image_get_selection(param[1].data.d_image));

  /* works not on INDEXED images */     

  if (gimp_drawable_is_indexed (Current.drawable->drawable_id) ||
      gimp_drawable_is_gray (Current.drawable->drawable_id) )
  {
    status = GIMP_PDB_EXECUTION_ERROR;
  }
  else
  {
    /* call dialog and rotate the colormap */

    INIT_I18N_UI(); 

    if (gimp_drawable_is_rgb(Current.drawable->drawable_id) && rcm_dialog())
    {
      gimp_progress_init(_("Rotating the colormap..."));

      gimp_tile_cache_ntiles(2 * (Current.drawable->width / gimp_tile_width() + 1));
      rcm(Current.drawable);
      gimp_displays_flush();
    }
    else
      status = GIMP_PDB_EXECUTION_ERROR;
  }
  
  values[0].data.d_status = status;
  if (status == GIMP_PDB_SUCCESS)
    gimp_drawable_detach(Current.drawable);
}