/* The GIMP -- an image manipulation program
 * Copyright (C) 1995 Spencer Kimball and Peter Mattis
 * mapcolor plugin
 * Copyright (C) 1998 Peter Kirchgessner
 * email: peter@kirchgessner.net, WWW: http://www.kirchgessner.net)
 *
 * 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.
 *
 */

/* Event history:
 * V 1.00, PK, 26-Oct-98: Creation.
 * V 1.01, PK, 21-Nov-99: Fix problem with working on layered images
 *                        Internationalization
 * V 1.02, PK, 19-Mar-00: Better explaining text/dialogue
 *                        Preview added
 *                        Fix problem with divide by zero
 * V 1.03,neo, 22-May-00: Fixed divide by zero in preview code.
 */

#define VERSIO                                     1.03
static char dversio[] =                          "v1.03  22-May-00";

#include "config.h"

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>

#include <gtk/gtk.h>

#include <libgimp/gimp.h>
#include <libgimp/gimpui.h>

#include "libgimp/stdplugins-intl.h"


#define PRV_WIDTH  50
#define PRV_HEIGHT 20

typedef struct
{
  GimpRGB  colors[4];
  gint32   map_mode;
  gboolean preview;
} PluginValues;

PluginValues plvals =
{
  {
    { 0.0, 0.0, 0.0, 1.0 },
    { 1.0, 1.0, 1.0, 1.0 },
    { 0.0, 0.0, 0.0, 1.0 },
    { 1.0, 1.0, 1.0, 1.0 },
  },
  0
};

static guchar redmap[256], greenmap[256], bluemap[256];

/* Declare some local functions.
 */
static void   query (void);
static void   run   (const gchar      *name,
                     gint              nparams,
                     const GimpParam  *param,
                     gint             *nreturn_vals,
                     GimpParam       **return_vals);

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

static void      update_img_preview (GimpDrawable *drawable,
                                     GimpPreview  *preview);

static gboolean  mapcolor_dialog    (GimpDrawable *drawable);
static void      get_mapping        (GimpRGB      *src_col1,
                                     GimpRGB      *src_col2,
                                     GimpRGB      *dst_col1,
                                     GimpRGB      *dst_col2,
                                     gint32        map_mode,
                                     guchar       *redmap,
                                     guchar       *greenmap,
                                     guchar       *bluemap);
static void      add_color_button   (gint          csel_index,
                                     gint          left,
                                     gint          top,
                                     GtkWidget    *table,
                                     GtkWidget    *preview);

static void      color_mapping      (GimpDrawable *drawable);

static gchar *csel_title[4] =
{
  N_("First Source Color"),
  N_("Second Source Color"),
  N_("First Destination Color"),
  N_("Second Destination Color")
};

MAIN ()

static void
query (void)

{
  static GimpParamDef adjust_args[] =
  {
    { GIMP_PDB_INT32,    "run_mode", "Interactive, non-interactive" },
    { GIMP_PDB_IMAGE,    "image",    "Input image (not used)" },
    { GIMP_PDB_DRAWABLE, "drawable", "Input drawable to adjust" }
  };

  static GimpParamDef map_args[] =
  {
    { GIMP_PDB_INT32,    "run_mode",   "Interactive, non-interactive" },
    { GIMP_PDB_IMAGE,    "image",      "Input image (not used)" },
    { GIMP_PDB_DRAWABLE, "drawable",   "Input drawable where colors are to map" },
    { GIMP_PDB_COLOR,    "srccolor_1", "First source color" },
    { GIMP_PDB_COLOR,    "srccolor_2", "Second source color" },
    { GIMP_PDB_COLOR,    "dstcolor_1", "First destination color" },
    { GIMP_PDB_COLOR,    "dstcolor_2", "Second destination color" },
    { GIMP_PDB_INT32,    "map_mode",   "Mapping mode (0: linear, others reserved)" }
  };

  gimp_install_procedure ("plug_in_color_adjust",
                          "Adjust color range given by foreground/background "
                          "color to black/white",
                          "The current foreground color is mapped to black "
                          "(black point), the current background color is "
                          "mapped to white (white point). Intermediate "
                          "colors are interpolated",
                          "Peter Kirchgessner",
                          "Peter Kirchgessner",
                          dversio,
                          N_("Adjust _FG-BG"),
                          "RGB*",
                          GIMP_PLUGIN,
                          G_N_ELEMENTS (adjust_args), 0,
                          adjust_args, NULL);

  gimp_plugin_menu_register ("plug_in_color_adjust",
                             "<Image>/Filters/Colors/Map");

  gimp_install_procedure ("plug_in_color_map",
                          "Map color range specified by two colors"
                          "to color range specified by two other color.",
                          "Map color range specified by two colors"
                          "to color range specified by two other color."
                          "Intermediate colors are interpolated.",
                          "Peter Kirchgessner",
                          "Peter Kirchgessner",
                          dversio,
                          N_("Color Range _Mapping..."),
                          "RGB*",
                          GIMP_PLUGIN,
                          G_N_ELEMENTS (map_args), 0,
                          map_args, NULL);

  gimp_plugin_menu_register ("plug_in_color_map",
                             "<Image>/Filters/Colors/Map");
}


static void
run (const gchar      *name,
     gint              nparams,
     const GimpParam  *param,
     gint             *nreturn_vals,
     GimpParam       **return_vals)

{
  static GimpParam   values[1];
  GimpRunMode        run_mode;
  GimpDrawable      *drawable = NULL;
  GimpPDBStatusType  status = GIMP_PDB_SUCCESS;
  gint               j;

  INIT_I18N ();

  run_mode = param[0].data.d_int32;

  *nreturn_vals = 1;
  *return_vals  = values;

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

  while (status == GIMP_PDB_SUCCESS)
    {
      if (nparams < 3)
        {
          status = GIMP_PDB_CALLING_ERROR;
          break;
        }

      /* Make sure the drawable is RGB color */
      drawable = gimp_drawable_get (param[2].data.d_drawable);
      if (!gimp_drawable_is_rgb (drawable->drawable_id))
        {
          g_message (_("Cannot operate on gray or indexed color images."));
          status = GIMP_PDB_EXECUTION_ERROR;
          break;
        }

      if (strcmp (name, "plug_in_color_adjust") == 0)
        {
          if (nparams != 3)  /* Make sure all the arguments are there */
            {
              status = GIMP_PDB_CALLING_ERROR;
              break;
            }

          gimp_context_get_foreground (plvals.colors);
          gimp_context_get_background (plvals.colors + 1);

          gimp_rgb_set (plvals.colors + 2, 0.0, 0.0, 0.0);
          gimp_rgb_set (plvals.colors + 3, 1.0, 1.0, 1.0);

          plvals.map_mode = 0;

          gimp_progress_init (_("Adjusting Foreground/Background..."));

          color_mapping (drawable);
          break;
        }

      if (strcmp (name, "plug_in_color_map") == 0)
        {
          if (run_mode == GIMP_RUN_NONINTERACTIVE)
            {
              if (nparams != 8)  /* Make sure all the arguments are there */
                {
                  status = GIMP_PDB_CALLING_ERROR;
                  break;
                }

              for (j = 0; j < 4; j++)
                {
                  plvals.colors[j] = param[3+j].data.d_color;
                }
              plvals.map_mode = param[7].data.d_int32;
            }
          else if (run_mode == GIMP_RUN_INTERACTIVE)
            {
              gimp_get_data (name, &plvals);

              gimp_context_get_foreground (plvals.colors);
              gimp_context_get_background (plvals.colors + 1);

              if (!mapcolor_dialog (drawable))
                break;
            }
          else if (run_mode == GIMP_RUN_WITH_LAST_VALS)
            {
              gimp_get_data (name, &plvals);
            }
          else
            {
              status = GIMP_PDB_CALLING_ERROR;
              break;
            }

          gimp_progress_init (_("Mapping colors..."));

          color_mapping (drawable);

          if (run_mode == GIMP_RUN_INTERACTIVE)
            gimp_set_data (name, &plvals, sizeof (plvals));

          break;
        }

      status = GIMP_PDB_EXECUTION_ERROR;
    }

  if ((status == GIMP_PDB_SUCCESS) && (run_mode != GIMP_RUN_NONINTERACTIVE))
    gimp_displays_flush ();

  if (drawable != NULL)
    gimp_drawable_detach (drawable);

  values[0].data.d_status = status;
}

static void
update_img_preview (GimpDrawable *drawable,
                    GimpPreview  *preview)
{
  guchar    redmap[256], greenmap[256], bluemap[256];
  gint      width, height, bpp;
  gboolean  has_alpha;
  guchar   *src, *dest, *s, *d;
  gint      j;

  get_mapping (plvals.colors,
               plvals.colors + 1,
               plvals.colors + 2,
               plvals.colors + 3,
               plvals.map_mode,
               redmap, greenmap, bluemap);

  gimp_preview_get_size (preview, &width, &height);
  bpp = gimp_drawable_bpp (drawable->drawable_id);
  src = gimp_drawable_get_thumbnail_data (drawable->drawable_id,
                                          &width, &height, &bpp);
  has_alpha = gimp_drawable_has_alpha (drawable->drawable_id);

  j = width * height;
  dest = g_new (guchar, j * bpp);

  s = src; d = dest;
  while (j-- > 0)
    {
      *(d++) = redmap[*(s++)];
      *(d++) = greenmap[*(s++)];
      *(d++) = bluemap[*(s++)];
      if (has_alpha)
        *(d++) = *(s++);
    }

  gimp_preview_draw_buffer (preview, dest, width * bpp);

  g_free (src);
  g_free (dest);
}

static gboolean
mapcolor_dialog (GimpDrawable *drawable)
{
  GtkWidget *dialog;
  GtkWidget *main_vbox;
  GtkWidget *preview;
  GtkWidget *frame;
  GtkWidget *table;
  gint       j;
  gboolean   run;

  gimp_ui_init ("mapcolor", TRUE);

  dialog = gimp_dialog_new (_("Map Color Range"), "mapcolor",
                            NULL, 0,
                            gimp_standard_help_func, "plug-in-color-map",

                            GTK_STOCK_CANCEL, GTK_RESPONSE_CANCEL,
                            GTK_STOCK_OK,     GTK_RESPONSE_OK,

                            NULL);

  main_vbox = gtk_vbox_new (FALSE, 12);
  gtk_container_set_border_width (GTK_CONTAINER (main_vbox), 12);
  gtk_container_add (GTK_CONTAINER (GTK_DIALOG (dialog)->vbox), main_vbox);
  gtk_widget_show (main_vbox);

  preview = gimp_aspect_preview_new (drawable, NULL);
  gtk_box_pack_start_defaults (GTK_BOX (main_vbox), preview);
  gtk_widget_show (preview);
  g_signal_connect_swapped (preview, "invalidated",
                            G_CALLBACK (update_img_preview),
                            drawable);

  for (j = 0; j < 2; j++)
    {
      frame = gimp_frame_new ((j == 0) ?
                              _("Source color range") :
                              _("Destination color range"));
      gtk_box_pack_start (GTK_BOX (main_vbox), frame, FALSE, FALSE, 0);
      gtk_widget_show (frame);

      /* The table keeps the color selections */
      table = gtk_table_new (1, 4, FALSE);
      gtk_table_set_col_spacings (GTK_TABLE (table), 6);
      gtk_container_add (GTK_CONTAINER (frame), table);
      gtk_widget_show (table);

      add_color_button (j * 2, 0, 0, table, preview);
      add_color_button (j * 2 + 1, 2, 0, table, preview);
    }

  gtk_widget_show (dialog);

  run = (gimp_dialog_run (GIMP_DIALOG (dialog)) == GTK_RESPONSE_OK);

  if (run)
    plvals.map_mode = 0;  /* Currently always linear mapping */

  gtk_widget_destroy (dialog);

  return run;
}

static void
add_color_button (gint       csel_index,
                  gint       left,
                  gint       top,
                  GtkWidget *table,
                  GtkWidget *preview)
{
  GtkWidget *button;

  button = gimp_color_button_new (gettext (csel_title[csel_index]),
                                  PRV_WIDTH, PRV_HEIGHT,
                                  &plvals.colors[csel_index],
                                  GIMP_COLOR_AREA_FLAT);
  gimp_table_attach_aligned (GTK_TABLE (table), left + 1, top,
                             (left == 0) ? _("From:") : _("To:"),
                             0.0, 0.5,
                             button, 1, TRUE);

  g_signal_connect (button, "color_changed",
                    G_CALLBACK (gimp_color_button_get_color),
                    &plvals.colors[csel_index]);
  g_signal_connect_swapped (button, "color_changed",
                            G_CALLBACK (gimp_preview_invalidate),
                            preview);
}

static void
get_mapping (GimpRGB *src_col1,
             GimpRGB *src_col2,
             GimpRGB *dst_col1,
             GimpRGB *dst_col2,
             gint32   map_mode,
             guchar  *redmap,
             guchar  *greenmap,
             guchar  *bluemap)
{
  guchar  src1[3];
  guchar  src2[3];
  guchar  dst1[3];
  guchar  dst2[3];
  gint    rgb, i, a, as, b, bs;
  guchar *colormap[3];

  /* Currently we always do a linear mapping */

  colormap[0] = redmap;
  colormap[1] = greenmap;
  colormap[2] = bluemap;

  gimp_rgb_get_uchar (src_col1, src1, src1 + 1, src1 + 2);
  gimp_rgb_get_uchar (src_col2, src2, src2 + 1, src2 + 2);
  gimp_rgb_get_uchar (dst_col1, dst1, dst1 + 1, dst1 + 2);
  gimp_rgb_get_uchar (dst_col2, dst2, dst2 + 1, dst2 + 2);

  switch (map_mode)
    {
    case 0:
    default:
      for (rgb = 0; rgb < 3; rgb++)
        {
          a = src1[rgb];  as = dst1[rgb];
          b = src2[rgb];  bs = dst2[rgb];

          if (b == a)
            b = a + 1;
          for (i = 0; i < 256; i++)
            {
              gint j = ((i - a) * (bs - as)) / (b - a) + as;
              colormap[rgb][i] = CLAMP0255(j);
            }
        }
      break;
    }
}

static void
mapcolor_func (const guchar *src,
               guchar       *dest,
               gint          bpp,
               gpointer      data)
{
  dest[0] = redmap[src[0]];
  dest[1] = greenmap[src[1]];
  dest[2] = bluemap[src[2]];
  if (bpp > 3)
    dest[3] = src[3];
}

static void
color_mapping (GimpDrawable *drawable)

{
  if (gimp_rgb_distance (&plvals.colors[0], &plvals.colors[1]) < 0.0001)
    return;

  if (!gimp_drawable_is_rgb (drawable->drawable_id))
    {
      g_message (_("Cannot operate on gray or indexed color images."));
      return;
    }

  gimp_tile_cache_ntiles (2 * (drawable->width / gimp_tile_width () + 1));

  get_mapping (plvals.colors,
               plvals.colors + 1,
               plvals.colors + 2,
               plvals.colors + 3,
               plvals.map_mode,
               redmap, greenmap, bluemap);

  gimp_rgn_iterate2 (drawable, 0 /* unused */, mapcolor_func, NULL);
}