/* GIMP - The GNU Image Manipulation Program
 * Copyright (C) 1995 Spencer Kimball and Peter Mattis
 *
 * 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 <gegl.h>
#include <gtk/gtk.h>

#include "libgimpbase/gimpbase.h"
#include "libgimpwidgets/gimpwidgets.h"

#include "dialogs-types.h"

#include "gegl/gimp-babl.h"

#include "core/gimpcontext.h"
#include "core/gimpimage.h"

#include "widgets/gimphelp-ids.h"
#include "widgets/gimpviewabledialog.h"
#include "widgets/gimpwidgets-utils.h"

#include "convert-precision-dialog.h"

#include "gimp-intl.h"


typedef struct _ConvertDialog ConvertDialog;

struct _ConvertDialog
{
  GimpImage                    *image;
  GimpComponentType             component_type;
  gboolean                      linear;
  GeglDitherMethod              layer_dither_method;
  GeglDitherMethod              text_layer_dither_method;
  GeglDitherMethod              channel_dither_method;
  GimpConvertPrecisionCallback  callback;
  gpointer                      user_data;
};


/*  local function prototypes  */

static void   convert_precision_dialog_free     (ConvertDialog    *private);
static void   convert_precision_dialog_response (GtkWidget        *widget,
                                                 gint              response_id,
                                                 ConvertDialog    *private);


/*  public functions  */

GtkWidget *
convert_precision_dialog_new (GimpImage                    *image,
                              GimpContext                  *context,
                              GtkWidget                    *parent,
                              GimpComponentType             component_type,
                              GeglDitherMethod              layer_dither_method,
                              GeglDitherMethod              text_layer_dither_method,
                              GeglDitherMethod              channel_dither_method,
                              GimpConvertPrecisionCallback  callback,
                              gpointer                      user_data)

{
  ConvertDialog *private;
  GtkWidget     *dialog;
  GtkWidget     *main_vbox;
  GtkWidget     *vbox;
  GtkWidget     *frame;
  const gchar   *enum_desc;
  gchar         *blurb;
  const Babl    *old_format;
  const Babl    *new_format;
  gint           old_bits;
  gint           new_bits;
  gboolean       dither;
  gboolean       linear;

  g_return_val_if_fail (GIMP_IS_IMAGE (image), NULL);
  g_return_val_if_fail (GIMP_IS_CONTEXT (context), NULL);
  g_return_val_if_fail (GTK_IS_WIDGET (parent), NULL);
  g_return_val_if_fail (callback != NULL, NULL);

  /* random formats with the right precision */
  old_format = gimp_image_get_layer_format (image, FALSE);
  new_format = gimp_babl_format (GIMP_RGB,
                                 gimp_babl_precision (component_type, FALSE),
                                 FALSE);

  old_bits = (babl_format_get_bytes_per_pixel (old_format) * 8 /
              babl_format_get_n_components (old_format));
  new_bits = (babl_format_get_bytes_per_pixel (new_format) * 8 /
              babl_format_get_n_components (new_format));

  /*  don't dither if we are converting to a higher bit depth,
   *  or to more than MAX_DITHER_BITS.
   */
  dither = (new_bits <  old_bits &&
            new_bits <= CONVERT_PRECISION_DIALOG_MAX_DITHER_BITS);

  /* when changing this logic, also change the same switch()
   * in gimptemplateeditor.h
   */
  switch (component_type)
    {
    case GIMP_COMPONENT_TYPE_U8:
      /* default to gamma when converting 8 bit */
      linear = FALSE;
      break;

    case GIMP_COMPONENT_TYPE_U16:
    case GIMP_COMPONENT_TYPE_U32:
    default:
      /* leave gamma alone by default when converting to 16/32 bit int */
      linear = gimp_babl_format_get_linear (old_format);
      break;

    case GIMP_COMPONENT_TYPE_HALF:
    case GIMP_COMPONENT_TYPE_FLOAT:
    case GIMP_COMPONENT_TYPE_DOUBLE:
      /* default to linear when converting to floating point */
      linear = TRUE;
      break;
    }

  private = g_slice_new0 (ConvertDialog);

  private->image                    = image;
  private->component_type           = component_type;
  private->linear                   = linear;
  private->layer_dither_method      = layer_dither_method;
  private->text_layer_dither_method = text_layer_dither_method;
  private->channel_dither_method    = channel_dither_method;
  private->callback                 = callback;
  private->user_data                = user_data;

  gimp_enum_get_value (GIMP_TYPE_COMPONENT_TYPE, component_type,
                       NULL, NULL, &enum_desc, NULL);

  blurb = g_strdup_printf (_("Convert Image to %s"), enum_desc);

  dialog = gimp_viewable_dialog_new (GIMP_VIEWABLE (image), context,
#if PENDING_TRANSLATION
                                     _("Encoding Conversion"),
#endif
                                     _("Precision Conversion"),
                                     "gimp-image-convert-precision",
                                     GIMP_ICON_CONVERT_PRECISION,
                                     blurb,
                                     parent,
                                     gimp_standard_help_func,
                                     GIMP_HELP_IMAGE_CONVERT_PRECISION,

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

                                     NULL);

  g_free (blurb);

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

  gtk_window_set_resizable (GTK_WINDOW (dialog), FALSE);

  g_object_weak_ref (G_OBJECT (dialog),
                     (GWeakNotify) convert_precision_dialog_free, private);

  g_signal_connect (dialog, "response",
                    G_CALLBACK (convert_precision_dialog_response),
                    private);

  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);


  /*  gamma  */

  frame = gimp_frame_new (_("Gamma"));
  gtk_box_pack_start (GTK_BOX (main_vbox), frame, FALSE, FALSE, 0);
  gtk_widget_show (frame);

  vbox = gimp_int_radio_group_new (FALSE, NULL,
                                   G_CALLBACK (gimp_radio_button_update),
                                   &private->linear,
                                   linear,

                                   _("Perceptual gamma (sRGB)"), FALSE, NULL,
                                   _("Linear light"),            TRUE,  NULL,

                                   NULL);
  gtk_container_add (GTK_CONTAINER (frame), vbox);
  gtk_widget_show (vbox);


  /*  dithering  */

  if (dither)
    {
      GtkWidget    *hbox;
      GtkWidget    *label;
      GtkWidget    *combo;
      GtkSizeGroup *size_group;

      frame = gimp_frame_new (_("Dithering"));
      gtk_box_pack_start (GTK_BOX (main_vbox), frame, FALSE, FALSE, 0);
      gtk_widget_show (frame);

      vbox = gtk_box_new (GTK_ORIENTATION_VERTICAL, 6);
      gtk_container_add (GTK_CONTAINER (frame), vbox);
      gtk_widget_show (vbox);

      size_group = gtk_size_group_new (GTK_SIZE_GROUP_HORIZONTAL);

      /*  layers  */

      hbox = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 6);
      gtk_box_pack_start (GTK_BOX (vbox), hbox, FALSE, FALSE, 0);
      gtk_widget_show (hbox);

      label = gtk_label_new_with_mnemonic (_("_Layers:"));
      gtk_label_set_xalign (GTK_LABEL (label), 0.0);
      gtk_box_pack_start (GTK_BOX (hbox), label, FALSE, FALSE, 0);
      gtk_size_group_add_widget (size_group, label);
      gtk_widget_show (label);

      combo = gimp_enum_combo_box_new (GEGL_TYPE_DITHER_METHOD);
      gtk_label_set_mnemonic_widget (GTK_LABEL (label), combo);
      gtk_box_pack_start (GTK_BOX (hbox), combo, TRUE, TRUE, 0);
      gtk_widget_show (combo);

      gimp_int_combo_box_connect (GIMP_INT_COMBO_BOX (combo),
                                  private->layer_dither_method,
                                  G_CALLBACK (gimp_int_combo_box_get_active),
                                  &private->layer_dither_method);

      /*  text layers  */

      hbox = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 6);
      gtk_box_pack_start (GTK_BOX (vbox), hbox, FALSE, FALSE, 0);
      gtk_widget_show (hbox);

      label = gtk_label_new_with_mnemonic (_("_Text Layers:"));
      gtk_label_set_xalign (GTK_LABEL (label), 0.0);
      gtk_box_pack_start (GTK_BOX (hbox), label, FALSE, FALSE, 0);
      gtk_size_group_add_widget (size_group, label);
      gtk_widget_show (label);

      combo = gimp_enum_combo_box_new (GEGL_TYPE_DITHER_METHOD);
      gtk_label_set_mnemonic_widget (GTK_LABEL (label), combo);
      gtk_box_pack_start (GTK_BOX (hbox), combo, TRUE, TRUE, 0);
      gtk_widget_show (combo);

      gimp_int_combo_box_connect (GIMP_INT_COMBO_BOX (combo),
                                  private->text_layer_dither_method,
                                  G_CALLBACK (gimp_int_combo_box_get_active),
                                  &private->text_layer_dither_method);

      gimp_help_set_help_data (combo,
                               _("Dithering text layers will make them "
                                 "uneditable"),
                               NULL);

      /*  channels  */

      hbox = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 6);
      gtk_box_pack_start (GTK_BOX (vbox), hbox, FALSE, FALSE, 0);
      gtk_widget_show (hbox);

      label = gtk_label_new_with_mnemonic (_("_Channels and Masks:"));
      gtk_label_set_xalign (GTK_LABEL (label), 0.0);
      gtk_box_pack_start (GTK_BOX (hbox), label, FALSE, FALSE, 0);
      gtk_size_group_add_widget (size_group, label);
      gtk_widget_show (label);

      combo = gimp_enum_combo_box_new (GEGL_TYPE_DITHER_METHOD);
      gtk_label_set_mnemonic_widget (GTK_LABEL (label), combo);
      gtk_box_pack_start (GTK_BOX (hbox), combo, TRUE, TRUE, 0);
      gtk_widget_show (combo);

      gimp_int_combo_box_connect (GIMP_INT_COMBO_BOX (combo),
                                  private->channel_dither_method,
                                  G_CALLBACK (gimp_int_combo_box_get_active),
                                  &private->channel_dither_method);

      g_object_unref (size_group);
    }

  return dialog;
}


/*  private functions  */

static void
convert_precision_dialog_free (ConvertDialog *private)
{
  g_slice_free (ConvertDialog, private);
}

static void
convert_precision_dialog_response (GtkWidget     *dialog,
                                   gint           response_id,
                                   ConvertDialog *private)
{
  if (response_id == GTK_RESPONSE_OK)
    {
      GimpPrecision precision = gimp_babl_precision (private->component_type,
                                                     private->linear);

      private->callback (dialog,
                         private->image,
                         precision,
                         private->layer_dither_method,
                         private->text_layer_dither_method,
                         private->channel_dither_method,
                         private->user_data);
    }
  else
    {
      gtk_widget_destroy (dialog);
    }
}