/*
 * This is a plug-in for the GIMP.
 *
 * Copyright (C) 1995 Spencer Kimball and Peter Mattis
 * Copyright (C) 1996 Torsten Martinsen
 *
 * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 * $Id: oilify.c,v 1.2 1997/09/27 10:30:37 nobody Exp $
 */

#include <stdio.h>
#include "gtk/gtk.h"
#include "libgimp/gimp.h"

#define ENTRY_WIDTH     30
#define SCALE_WIDTH     125
#define HISTSIZE	256

typedef struct {
  gdouble mask_size;
} OilifyVals;

typedef struct {
  gint run;
} OilifyInterface;

/* Declare local functions.
 */
static void      query  (void);
static void      run    (char      *name,
			 int        nparams,
			 GParam    *param,
			 int       *nreturn_vals,
			 GParam   **return_vals);
static void      oilify (GDrawable * drawable);

static gint      oilify_dialog ();

static void      oilify_close_callback  (GtkWidget *widget,
					 gpointer   data);
static void      oilify_ok_callback     (GtkWidget *widget,
					 gpointer   data);
static void      oilify_scale_update    (GtkAdjustment *adjustment,
					  double        *scale_val);
static void      oilify_entry_update    (GtkWidget *widget,
					  gdouble *value);
static void      dialog_create_value     (char *title,
					  GtkTable *table,
					  int row,
					  gdouble *value,
					  double left,
					  double right);

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

static OilifyVals ovals =
{
  7.0      /*  mask size  */
};

static OilifyInterface oint =
{
  FALSE     /*  run  */
};


MAIN ()

static void
query ()
{
  static GParamDef args[] =
  {
    { PARAM_INT32, "run_mode", "Interactive, non-interactive" },
    { PARAM_IMAGE, "image", "Input image (unused)" },
    { PARAM_DRAWABLE, "drawable", "Input drawable" },
    { PARAM_INT32, "mask_size", "Oil paint mask size" },
  };
  static GParamDef *return_vals = NULL;
  static int nargs = sizeof (args) / sizeof (args[0]);
  static int nreturn_vals = 0;

  gimp_install_procedure ("plug_in_oilify",
			  "Modify the specified drawable to resemble an oil painting",
			  "This function performs the well-known oil-paint effect on the specified drawable.  The size of the input mask is specified by 'mask_size'.",
			  "Torsten Martinsen",
			  "Torsten Martinsen",
			  "1996",
			  "<Image>/Filters/Artistic/Oilify",
			  "RGB*, GRAY*",
			  PROC_PLUG_IN,
			  nargs, nreturn_vals,
			  args, return_vals);
}

static void
run (char    *name,
     int      nparams,
     GParam  *param,
     int     *nreturn_vals,
     GParam **return_vals)
{
  static GParam values[1];
  GDrawable *drawable;
  GRunModeType run_mode;
  GStatusType status = STATUS_SUCCESS;

  run_mode = param[0].data.d_int32;

  *nreturn_vals = 1;
  *return_vals = values;

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

  switch (run_mode)
    {
    case RUN_INTERACTIVE:
      /*  Possibly retrieve data  */
      gimp_get_data ("plug_in_oilify", &ovals);

      /*  First acquire information with a dialog  */
      if (! oilify_dialog ())
	return;
      break;

    case RUN_NONINTERACTIVE:
      /*  Make sure all the arguments are there!  */
      if (nparams != 4)
	status = STATUS_CALLING_ERROR;
      if (status == STATUS_SUCCESS)
	{
	  ovals.mask_size = (gdouble) param[3].data.d_int32;
	}
      if (status == STATUS_SUCCESS &&
	  (ovals.mask_size < 1.0))
	status = STATUS_CALLING_ERROR;
      break;

    case RUN_WITH_LAST_VALS:
      /*  Possibly retrieve data  */
      gimp_get_data ("plug_in_oilify", &ovals);
      break;

    default:
      break;
    }

  /*  Get the specified drawable  */
  drawable = gimp_drawable_get (param[2].data.d_drawable);

  /*  Make sure that the drawable is gray or RGB color  */
  if ((status == STATUS_SUCCESS) &&
      (gimp_drawable_color (drawable->id) || gimp_drawable_gray (drawable->id)))
    {
      gimp_progress_init ("Oil Painting...");
      gimp_tile_cache_ntiles (2 * (drawable->width / gimp_tile_width () + 1));
      oilify (drawable);

      if (run_mode != RUN_NONINTERACTIVE)
	gimp_displays_flush ();

      /*  Store data  */
      if (run_mode == RUN_INTERACTIVE)
	gimp_set_data ("plug_in_oilify", &ovals, sizeof (OilifyVals));
    }
  else
    {
      /* gimp_message ("oilify: cannot operate on indexed color images"); */
      status = STATUS_EXECUTION_ERROR;
    }

  values[0].data.d_status = status;

  gimp_drawable_detach (drawable);
}

/*
 * For each RGB channel, replace the pixel at (x,y) with the
 * value that occurs most often in the n x n chunk centered
 * at (x,y).
 */
static void
oilify (GDrawable *drawable)
{
  GPixelRgn src_rgn, dest_rgn;
  gint bytes;
  gint width, height;
  guchar *src_row, *src;
  guchar *dest_row, *dest;
  gint x, y, c, b, i, px, xx, yy, n;
  gint x1, y1, x2, y2;
  gint x3, y3, x4, y4;
  gint Val[4];
  gint Cnt[4];
  gint Hist[4][HISTSIZE];
  gpointer pr1, pr2;
  gint progress, max_progress;

  /*  get the selection bounds  */
  gimp_drawable_mask_bounds (drawable->id, &x1, &y1, &x2, &y2);
  progress = 0;
  max_progress = (x2 - x1) * (y2 - y1);

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

  n = (int) ovals.mask_size / 2;

  gimp_pixel_rgn_init (&dest_rgn, drawable, x1, y1, (x2 - x1), (y2 - y1), TRUE, TRUE);

  for (pr1 = gimp_pixel_rgns_register (1, &dest_rgn); pr1 != NULL; pr1 = gimp_pixel_rgns_process (pr1))
    {
      dest_row = dest_rgn.data;

      for (y = dest_rgn.y; y < (dest_rgn.y + dest_rgn.h); y++)
	{
	  dest = dest_row;

	  for (x = dest_rgn.x; x < (dest_rgn.x + dest_rgn.w); x++)
	    {
	      for (b = 0; b < bytes; b++)
		{
		  Cnt[b] = 0;
		  Val[b] = 0;
		  for (i = 0; i < HISTSIZE; i++)
		    Hist[b][i] = 0;
		}

	      x3 = CLAMP ((x - n), x1, x2);
	      y3 = CLAMP ((y - n), y1, y2);
	      x4 = CLAMP ((x + n + 1), x1, x2);
	      y4 = CLAMP ((y + n + 1), y1, y2);

	      gimp_pixel_rgn_init (&src_rgn, drawable, x3, y3, (x4 - x3), (y4 - y3), FALSE, FALSE);

	      for (pr2 = gimp_pixel_rgns_register (1, &src_rgn); pr2 != NULL; pr2 = gimp_pixel_rgns_process (pr2))
		{
		  src_row = src_rgn.data;

		  for (yy = 0; yy < src_rgn.h; yy++)
		    {
		      src = src_row;

		      for (xx = 0; xx < src_rgn.w; xx++)
			{
			  for (b = 0; b < bytes; b++)
			    {
			      if ((c = ++Hist[b][px = src[b]]) > Cnt[b])
				{
				  Val[b] = px;
				  Cnt[b] = c;
				}
			    }

			  src += src_rgn.bpp;
			}

		      src_row += src_rgn.rowstride;
		    }
		}

	      for (b = 0; b < bytes; b++)
		*dest++ = Val[b];
	    }

	  dest_row += dest_rgn.rowstride;
	}

      progress += dest_rgn.w * dest_rgn.h;
      gimp_progress_update ((double) progress / (double) max_progress);
    }

  /*  update the oil-painted region  */
  gimp_drawable_flush (drawable);
  gimp_drawable_merge_shadow (drawable->id, TRUE);
  gimp_drawable_update (drawable->id, x1, y1, (x2 - x1), (y2 - y1));
}

static gint
oilify_dialog ()
{
  GtkWidget *dlg;
  GtkWidget *button;
  GtkWidget *frame;
  GtkWidget *table;
  gchar **argv;
  gint argc;

  argc = 1;
  argv = g_new (gchar *, 1);
  argv[0] = g_strdup ("oilify");

  gtk_init (&argc, &argv);
  gtk_rc_parse (gimp_gtkrc ());

  dlg = gtk_dialog_new ();
  gtk_window_set_title (GTK_WINDOW (dlg), "Oilify");
  gtk_window_position (GTK_WINDOW (dlg), GTK_WIN_POS_MOUSE);
  gtk_signal_connect (GTK_OBJECT (dlg), "destroy",
		      (GtkSignalFunc) oilify_close_callback,
		      NULL);

  /*  Action area  */
  button = gtk_button_new_with_label ("OK");
  GTK_WIDGET_SET_FLAGS (button, GTK_CAN_DEFAULT);
  gtk_signal_connect (GTK_OBJECT (button), "clicked",
                      (GtkSignalFunc) oilify_ok_callback,
                      dlg);
  gtk_box_pack_start (GTK_BOX (GTK_DIALOG (dlg)->action_area), button, TRUE, TRUE, 0);
  gtk_widget_grab_default (button);
  gtk_widget_show (button);

  button = gtk_button_new_with_label ("Cancel");
  GTK_WIDGET_SET_FLAGS (button, GTK_CAN_DEFAULT);
  gtk_signal_connect_object (GTK_OBJECT (button), "clicked",
			     (GtkSignalFunc) gtk_widget_destroy,
			     GTK_OBJECT (dlg));
  gtk_box_pack_start (GTK_BOX (GTK_DIALOG (dlg)->action_area), button, TRUE, TRUE, 0);
  gtk_widget_show (button);

  /*  parameter settings  */
  frame = gtk_frame_new ("Parameter Settings");
  gtk_frame_set_shadow_type (GTK_FRAME (frame), GTK_SHADOW_ETCHED_IN);
  gtk_container_border_width (GTK_CONTAINER (frame), 10);
  gtk_box_pack_start (GTK_BOX (GTK_DIALOG (dlg)->vbox), frame, TRUE, TRUE, 0);
  table = gtk_table_new (2, 3, FALSE);
  gtk_container_border_width (GTK_CONTAINER (table), 10);
  gtk_container_add (GTK_CONTAINER (frame), table);

  dialog_create_value("Mask Size", GTK_TABLE(table), 1, &ovals.mask_size, 1.0, 50.0);

  gtk_widget_show (frame);
  gtk_widget_show (table);
  gtk_widget_show (dlg);

  gtk_main ();
  gdk_flush ();

  return oint.run;
}


/*  Oilify interface functions  */

static void
oilify_close_callback (GtkWidget *widget,
		       gpointer   data)
{
  gtk_main_quit ();
}

static void
oilify_ok_callback (GtkWidget *widget,
		    gpointer   data)
{
  oint.run = TRUE;
  gtk_widget_destroy (GTK_WIDGET (data));
}

/*
 * Thanks to Quartic for these.
 */
static void
dialog_create_value(char *title, GtkTable *table, int row, gdouble *value, double left, double right)
{
	GtkWidget *label;
	GtkWidget *scale;
	GtkWidget *entry;
	GtkObject *scale_data;
	char       buf[256];

	label = gtk_label_new(title);
	gtk_misc_set_alignment(GTK_MISC(label), 0.0, 0.5);
	gtk_table_attach(table, label, 0, 1, row, row + 1, GTK_FILL, GTK_FILL, 4, 0);
	gtk_widget_show(label);

	scale_data = gtk_adjustment_new(*value, left, right,
					1.0, 5.0, 5.0);

	gtk_signal_connect(GTK_OBJECT(scale_data), "value_changed",
			   (GtkSignalFunc) oilify_scale_update,
			   value);

	scale = gtk_hscale_new(GTK_ADJUSTMENT(scale_data));
	gtk_widget_set_usize(scale, SCALE_WIDTH, 0);
	gtk_table_attach(table, scale, 1, 2, row, row + 1, GTK_EXPAND | GTK_FILL, GTK_FILL, 0, 0);
	gtk_scale_set_draw_value(GTK_SCALE(scale), FALSE);
	gtk_scale_set_digits(GTK_SCALE(scale), 3);
	gtk_range_set_update_policy(GTK_RANGE(scale), GTK_UPDATE_CONTINUOUS);
	gtk_widget_show(scale);

	entry = gtk_entry_new();
	gtk_object_set_user_data(GTK_OBJECT(entry), scale_data);
	gtk_object_set_user_data(scale_data, entry);
	gtk_widget_set_usize(entry, ENTRY_WIDTH, 0);
	sprintf(buf, "%.0f", *value);
	gtk_entry_set_text(GTK_ENTRY(entry), buf);
	gtk_signal_connect(GTK_OBJECT(entry), "changed",
			   (GtkSignalFunc) oilify_entry_update,
			   value);
	gtk_table_attach(GTK_TABLE(table), entry, 2, 3, row, row + 1, GTK_FILL, GTK_FILL, 4, 0);
	gtk_widget_show(entry);
}

static void
oilify_entry_update(GtkWidget *widget, gdouble *value)
{
	GtkAdjustment *adjustment;
	gdouble        new_value;

	new_value = atof(gtk_entry_get_text(GTK_ENTRY(widget)));

	if (*value != new_value) {
		adjustment = gtk_object_get_user_data(GTK_OBJECT(widget));

		if ((new_value >= adjustment->lower) &&
		    (new_value <= adjustment->upper)) {
			*value            = new_value;
			adjustment->value = new_value;

			gtk_signal_emit_by_name(GTK_OBJECT(adjustment), "value_changed");
		} /* if */
	} /* if */
}

static void
oilify_scale_update (GtkAdjustment *adjustment, gdouble *value)
{
	GtkWidget *entry;
	char       buf[256];

	if (*value != adjustment->value) {
		*value = adjustment->value;

		entry = gtk_object_get_user_data(GTK_OBJECT(adjustment));
		sprintf(buf, "%.0f", *value);

		gtk_signal_handler_block_by_data(GTK_OBJECT(entry), value);
		gtk_entry_set_text(GTK_ENTRY(entry), buf);
		gtk_signal_handler_unblock_by_data(GTK_OBJECT(entry), value);
	} /* if */
}
