/*
 *  Wavelet decompose plug-in by Miroslav Talasek, miroslav.talasek@seznam.cz
 */

/*
 * 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 3 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, see <https://www.gnu.org/licenses/>.
 */

#include "config.h"

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

#include "libgimp/stdplugins-intl.h"


#define PLUG_IN_PROC   "plug-in-wavelet-decompose"
#define PLUG_IN_ROLE   "gimp-wavelet-decompose"
#define PLUG_IN_BINARY "wavelet-decompose"

#define SCALE_WIDTH   120
#define ENTRY_WIDTH     5


typedef struct
{
  gint scales;
  gint create_group;
  gint create_masks;
} WaveletDecomposeParams;


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

static void      wavelet_blur             (gint32            drawable_id,
                                           gint              radius);


static gboolean  wavelet_decompose_dialog (void);


/* create a few globals, set default values */
static WaveletDecomposeParams wavelet_params =
{
  5, /* default scales */
  1, /* create group */
  0  /* do not add mask by default */
};

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


MAIN ()


static void
query (void)
{
  static const GimpParamDef args[] =
  {
    { GIMP_PDB_INT32,    "run-mode",     "The run mode { RUN-INTERACTIVE (0), "
                                         "RUN-NONINTERACTIVE (1) }" },
    { GIMP_PDB_IMAGE,    "image",        "Input image (unused)"   },
    { GIMP_PDB_DRAWABLE, "drawable",     "Input drawable"         },
    { GIMP_PDB_INT32,    "scales",       "Number of scales (1-7)" },
    { GIMP_PDB_INT32,    "create-group", "Create a layer group to store the "
                                         "decomposition" },
    { GIMP_PDB_INT32,    "create-masks", "Add a layer mask to each scales "
                                         "layers" }
  };

  gimp_install_procedure (PLUG_IN_PROC,
                          N_("Wavelet decompose"),
                          "Compute and render wavelet scales",
                          "Miroslav Talasek <miroslav.talasek@seznam.cz>",
                          "Miroslav Talasek <miroslav.talasek@seznam.cz>",
                          "19january 2017",
                          N_("_Wavelet-decompose..."),
                          "RGB*, GRAY*",
                          GIMP_PLUGIN,
                          G_N_ELEMENTS (args), 0,
                          args, NULL);

  gimp_plugin_menu_register (PLUG_IN_PROC, "<Image>/Filters/Enhance");
}

static void
run (const gchar      *name,
     gint              nparams,
     const GimpParam  *param,
     gint             *nreturn_vals,
     GimpParam       **return_vals)
{
  static GimpParam   values[1];
  GimpPDBStatusType  status = GIMP_PDB_SUCCESS;
  gint32             image_id;
  gint32             drawable_id;
  GimpRunMode        run_mode;

  run_mode = param[0].data.d_int32;

  INIT_I18N();
  gegl_init (NULL, NULL);

  *nreturn_vals = 1;
  *return_vals  = values;

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

  image_id    = param[1].data.d_image;
  drawable_id = param[2].data.d_drawable;

  switch (run_mode)
    {
    case GIMP_RUN_INTERACTIVE:
      gimp_get_data (PLUG_IN_PROC, &wavelet_params);

      if (! wavelet_decompose_dialog ())
        return;
      break;

    case GIMP_RUN_NONINTERACTIVE:
      if (nparams != 6)
        {
          status = GIMP_PDB_CALLING_ERROR;
        }
      else
        {
          wavelet_params.scales       = param[3].data.d_int32;
          wavelet_params.create_group = param[4].data.d_int32;
          wavelet_params.create_masks = param[5].data.d_int32;
        }
      break;

    case GIMP_RUN_WITH_LAST_VALS:
      gimp_get_data (PLUG_IN_PROC, &wavelet_params);
      break;

    default:
      break;
    }

  if (status == GIMP_PDB_SUCCESS)
    {
      gint32        *scale_ids;
      gint32         new_scale_id;
      gint32         parent_id;
      GimpLayerMode  grain_extract_mode = GIMP_LAYER_MODE_GRAIN_EXTRACT;
      GimpLayerMode  grain_merge_mode   = GIMP_LAYER_MODE_GRAIN_MERGE;
      gint           id;

      gimp_progress_init (_("Wavelet-Decompose"));

      gimp_image_undo_group_start (image_id);

      gimp_image_freeze_layers (image_id);

      if (wavelet_params.create_group)
        {
          gint32 group_id = gimp_layer_group_new (image_id);
          gimp_item_set_name (group_id, _("Decomposition"));
          gimp_item_set_visible (group_id, FALSE);
          gimp_image_insert_layer (image_id, group_id,
                                   gimp_item_get_parent (drawable_id),
                                   gimp_image_get_item_position (image_id,
                                                                 drawable_id));
          parent_id = group_id;
        }
      else
        parent_id = -1;

      scale_ids = g_new (gint32, wavelet_params.scales);
      new_scale_id = gimp_layer_copy (drawable_id);
      gimp_image_insert_layer (image_id, new_scale_id, parent_id,
                               gimp_image_get_item_position (image_id,
                                                             drawable_id));

      /* the exact result of the grain-extract and grain-merge modes depends on
       * the choice of (gamma-corrected) midpoint intensity value.  for the
       * non-legacy modes, the midpoint value is 0.5, which isn't representable
       * exactly using integer precision.  for the legacy modes, the midpoint
       * value is 128/255 (i.e., 0x80), which is representable exactly using
       * (gamma-corrected) integer precision.  we therefore use the legacy
       * modes when the input image precision is integer, and only use the
       * (preferable) non-legacy modes when the input image precision is
       * floating point.
       *
       * this avoids imperfect reconstruction of the image when using integer
       * precision.  see bug #786844.
       */
      switch (gimp_image_get_precision (image_id))
        {
        case GIMP_PRECISION_U8_LINEAR:
        case GIMP_PRECISION_U8_GAMMA:
        case GIMP_PRECISION_U16_LINEAR:
        case GIMP_PRECISION_U16_GAMMA:
        case GIMP_PRECISION_U32_LINEAR:
        case GIMP_PRECISION_U32_GAMMA:
          grain_extract_mode = GIMP_LAYER_MODE_GRAIN_EXTRACT_LEGACY;
          grain_merge_mode   = GIMP_LAYER_MODE_GRAIN_MERGE_LEGACY;
          break;

        case GIMP_PRECISION_HALF_LINEAR:
        case GIMP_PRECISION_HALF_GAMMA:
        case GIMP_PRECISION_FLOAT_LINEAR:
        case GIMP_PRECISION_FLOAT_GAMMA:
        case GIMP_PRECISION_DOUBLE_LINEAR:
        case GIMP_PRECISION_DOUBLE_GAMMA:
          grain_extract_mode = GIMP_LAYER_MODE_GRAIN_EXTRACT;
          grain_merge_mode   = GIMP_LAYER_MODE_GRAIN_MERGE;
          break;
        }

      for (id = 0 ; id < wavelet_params.scales; ++id)
        {
          gint32 blur_id, tmp_id;
          gchar  scale_name[20];

          gimp_progress_update ((gdouble) id / (gdouble) wavelet_params.scales);

          scale_ids[id] = new_scale_id;

          g_snprintf (scale_name, sizeof (scale_name), _("Scale %d"), id + 1);
          gimp_item_set_name (new_scale_id, scale_name);

          tmp_id = gimp_layer_copy (new_scale_id);
          gimp_image_insert_layer (image_id, tmp_id, parent_id,
                                   gimp_image_get_item_position (image_id,
                                                                 new_scale_id));
          wavelet_blur (tmp_id, pow(2.0, id));

          blur_id = gimp_layer_copy (tmp_id);
          gimp_image_insert_layer (image_id, blur_id, parent_id,
                                   gimp_image_get_item_position (image_id,
                                                                 tmp_id));

          gimp_layer_set_mode (tmp_id, grain_extract_mode);
          new_scale_id = gimp_image_merge_down (image_id, tmp_id,
                                                GIMP_EXPAND_AS_NECESSARY);
          scale_ids[id] = new_scale_id;

          gimp_item_set_visible (new_scale_id, FALSE);

          new_scale_id = blur_id;
        }

      gimp_item_set_name (new_scale_id, _("Residual"));

      for (id = 0; id < wavelet_params.scales; id++)
        {
          gimp_image_reorder_item (image_id, scale_ids[id], parent_id,
                               gimp_image_get_item_position (image_id,
                                                             new_scale_id));
          gimp_layer_set_mode (scale_ids[id], grain_merge_mode);

          if (wavelet_params.create_masks)
            {
              gint32 mask_id = gimp_layer_create_mask (scale_ids[id],
                                                       GIMP_ADD_MASK_WHITE);
              gimp_layer_add_mask (scale_ids[id], mask_id);
            }

          gimp_item_set_visible (scale_ids[id], TRUE);
        }

      if (wavelet_params.create_group)
        gimp_item_set_visible (parent_id, TRUE);

      g_free (scale_ids);

      gimp_image_thaw_layers (image_id);

      gimp_image_undo_group_end (image_id);

      gimp_progress_update (1.0);

      values[0].data.d_status = status;
      gimp_displays_flush ();

      /* set data for next use of filter */
      if (run_mode == GIMP_RUN_INTERACTIVE)
        gimp_set_data (PLUG_IN_PROC,
                       &wavelet_params, sizeof (WaveletDecomposeParams));
    }

  gegl_exit ();
}

static void
wavelet_blur (gint32 drawable_id,
              gint   radius)
{
  gint x, y, width, height;

  if (gimp_drawable_mask_intersect (drawable_id, &x, &y, &width, &height))
    {
      GeglBuffer *buffer = gimp_drawable_get_buffer (drawable_id);
      GeglBuffer *shadow = gimp_drawable_get_shadow_buffer (drawable_id);

      gegl_render_op (buffer, shadow,
                      "gegl:wavelet-blur",
                      "radius", (gdouble) radius,
                      NULL);

      gegl_buffer_flush (shadow);
      gimp_drawable_merge_shadow (drawable_id, FALSE);
      gimp_drawable_update (drawable_id, x, y, width, height);
      g_object_unref (buffer);
      g_object_unref (shadow);
    }
}

static gboolean
wavelet_decompose_dialog (void)
{
  GtkWidget *dialog;
  GtkWidget *main_vbox;
  GtkWidget *table;
  GtkWidget *button;
  GtkObject *adj;
  gboolean   run;

  gimp_ui_init (PLUG_IN_BINARY, TRUE);

  dialog = gimp_dialog_new (_("Wavelet decompose"), PLUG_IN_ROLE,
                            NULL, 0,
                            gimp_standard_help_func, PLUG_IN_PROC,

                            _("_Cancel"), GTK_RESPONSE_CANCEL,
                            _("_OK"),     GTK_RESPONSE_OK,

                            NULL);

  gtk_dialog_set_alternative_button_order (GTK_DIALOG (dialog),
                                           GTK_RESPONSE_OK,
                                           GTK_RESPONSE_CANCEL,
                                           -1);

  gimp_window_set_transient (GTK_WINDOW (dialog));

  main_vbox = gtk_box_new (GTK_ORIENTATION_VERTICAL, 12);
  gtk_container_set_border_width (GTK_CONTAINER (main_vbox), 12);
  gtk_box_pack_start (GTK_BOX (gtk_dialog_get_content_area (GTK_DIALOG (dialog))),
                      main_vbox, TRUE, TRUE, 0);
  gtk_widget_show (main_vbox);

  table = gtk_table_new (3, 1, FALSE);
  gtk_table_set_col_spacings (GTK_TABLE (table), 6);
  gtk_table_set_row_spacings (GTK_TABLE (table), 6);
  gtk_box_pack_start (GTK_BOX (main_vbox), table, FALSE, FALSE, 0);
  gtk_widget_show (table);

  /* scales */

  adj = gimp_scale_entry_new (GTK_TABLE (table), 0, 0,
                              _("Scales:"), SCALE_WIDTH, ENTRY_WIDTH,
                              wavelet_params.scales,
                              1.0, 7.0, 1.0, 1.0, 0,
                              TRUE, 0, 0,
                              NULL, NULL);

  g_signal_connect (adj, "value-changed",
                    G_CALLBACK (gimp_int_adjustment_update),
                    &wavelet_params.scales);

  /* create group layer */

  button = gtk_check_button_new_with_mnemonic (_("Create a layer group to store the decomposition"));
  gtk_box_pack_start (GTK_BOX (main_vbox), button, FALSE, FALSE, 0);
  gtk_toggle_button_set_active (GTK_TOGGLE_BUTTON (button),
                                wavelet_params.create_group);
  gtk_widget_show (button);

  g_signal_connect (button, "toggled",
                    G_CALLBACK (gimp_toggle_button_update),
                    &wavelet_params.create_group);

  /* create layer masks */

  button = gtk_check_button_new_with_mnemonic (_("Add a layer mask to each scales layers"));
  gtk_box_pack_start (GTK_BOX (main_vbox), button, FALSE, FALSE, 0);
  gtk_toggle_button_set_active (GTK_TOGGLE_BUTTON (button),
                                wavelet_params.create_masks);
  gtk_widget_show (button);

  g_signal_connect (button, "toggled",
                    G_CALLBACK (gimp_toggle_button_update),
                    &wavelet_params.create_masks);

  gtk_widget_show (dialog);

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

  gtk_widget_destroy (dialog);

  return run;
}