gimp/libgimp/gimpvectorloadprocedure.c

/* GIMP - The GNU Image Manipulation Program
 * Copyright (C) 1995 Spencer Kimball and Peter Mattis
 *
 * gimpvectorloadprocedure.c
 * Copyright (C) 2024 Jehan
 *
 * 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 "gimp.h"

#include "libgimpbase/gimpwire.h" /* FIXME kill this include */

#include "gimpvectorloadprocedure.h"
#include "gimppdb_pdb.h"
#include "gimpplugin-private.h"
#include "gimpprocedureconfig-private.h"

#include "libgimp-intl.h"


/**
 * GimpVectorLoadProcedure:
 *
 * A [class@Procedure] subclass that makes it easier to write load procedures
 * for vector image formats.
 *
 * It automatically adds the standard arguments:
 * ([enum@RunMode], [iface@Gio.File], int width, int height)
 *
 * and the standard return value: ( [class@Image] )
 *
 * It is possible to add additional arguments.
 *
 * When invoked via [method@Procedure.run], it unpacks these standard
 * arguments and calls @run_func which is a [callback@RunImageFunc]. The
 * [class@ProcedureConfig] of [callback@GimpRunVectorLoadFunc] contains
 * additionally added arguments but also the arguments added by this class.
 */


struct _GimpVectorLoadProcedure
{
  GimpLoadProcedure      parent_instance;

  GimpRunVectorLoadFunc  run_func;
  gpointer               run_data;
  GDestroyNotify         run_data_destroy;
};

static void                  gimp_vector_load_procedure_constructed   (GObject              *object);
static void                  gimp_vector_load_procedure_finalize      (GObject              *object);

static void                  gimp_vector_load_procedure_install       (GimpProcedure        *procedure);
static GimpValueArray      * gimp_vector_load_procedure_run           (GimpProcedure        *procedure,
                                                                       const GimpValueArray *args);


G_DEFINE_FINAL_TYPE (GimpVectorLoadProcedure, gimp_vector_load_procedure, GIMP_TYPE_LOAD_PROCEDURE)

#define parent_class gimp_vector_load_procedure_parent_class


static void
gimp_vector_load_procedure_class_init (GimpVectorLoadProcedureClass *klass)
{
  GObjectClass       *object_class    = G_OBJECT_CLASS (klass);
  GimpProcedureClass *procedure_class = GIMP_PROCEDURE_CLASS (klass);

  object_class->constructed      = gimp_vector_load_procedure_constructed;
  object_class->finalize         = gimp_vector_load_procedure_finalize;

  procedure_class->install       = gimp_vector_load_procedure_install;
  procedure_class->run           = gimp_vector_load_procedure_run;
}

static void
gimp_vector_load_procedure_init (GimpVectorLoadProcedure *procedure)
{
}

static void
gimp_vector_load_procedure_constructed (GObject *object)
{
  GimpProcedure *procedure = GIMP_PROCEDURE (object);

  G_OBJECT_CLASS (parent_class)->constructed (object);

  GIMP_PROC_ARG_INT (procedure, "width",
                     _("_Width (pixels)"),
                     "Width (in pixels) to load the image in. "
                     "(0 for the corresponding width per native ratio)",
                     0, GIMP_MAX_IMAGE_SIZE, 0,
                     GIMP_PARAM_READWRITE);

  GIMP_PROC_ARG_INT (procedure, "height",
                     _("_Height (pixels)"),
                     "Height (in pixels) to load the image in. "
                     "(0 for the corresponding height per native ratio)",
                     0, GIMP_MAX_IMAGE_SIZE, 0,
                     GIMP_PARAM_READWRITE);

  GIMP_PROC_ARG_BOOLEAN (procedure, "keep-ratio",
                         _("_Keep aspect ratio"),
                         _("Force dimensions with aspect ratio"),
                         TRUE,
                         G_PARAM_READWRITE);
  GIMP_PROC_ARG_BOOLEAN (procedure, "prefer-native-dimensions",
                         _("_Prefer native dimensions"),
                         _("Load and use dimensions from source file"),
                         FALSE,
                         G_PARAM_READWRITE);

  /* Note: the "pixel-density" is saved in pixels per inch. "physical-unit"
   * property is only there for display.
   */
  GIMP_PROC_AUX_ARG_DOUBLE (procedure, "pixel-density",
                            _("Resolu_tion"),
                            _("Pixel Density: number of pixels per physical unit"),
                            1.0, 5000.0, 300.0,
                            G_PARAM_READWRITE);
  GIMP_PROC_AUX_ARG_INT (procedure, "physical-unit",
                         _("Unit"),
                         _("Physical unit"),
                         GIMP_UNIT_INCH, GIMP_UNIT_PICA, GIMP_UNIT_INCH,
                         G_PARAM_READWRITE);
}

static void
gimp_vector_load_procedure_finalize (GObject *object)
{
  GimpVectorLoadProcedure *procedure = GIMP_VECTOR_LOAD_PROCEDURE (object);

  if (procedure->run_data_destroy)
    procedure->run_data_destroy (procedure->run_data);

  G_OBJECT_CLASS (parent_class)->finalize (object);
}

static void
gimp_vector_load_procedure_install (GimpProcedure *procedure)
{
  GIMP_PROCEDURE_CLASS (parent_class)->install (procedure);

  _gimp_pdb_set_file_proc_handles_vector (gimp_procedure_get_name (procedure));
}

static GimpValueArray *
gimp_vector_load_procedure_run (GimpProcedure        *procedure,
                                const GimpValueArray *args)
{
  GimpPlugIn              *plug_in;
  GimpVectorLoadProcedure *load_proc = GIMP_VECTOR_LOAD_PROCEDURE (procedure);
  GimpValueArray          *remaining;
  GimpValueArray          *return_values;
  GimpProcedureConfig     *config;
  GimpImage               *image    = NULL;
  GimpMetadata            *metadata = NULL;
  gchar                   *mimetype = NULL;
  GimpMetadataLoadFlags    flags    = GIMP_METADATA_LOAD_ALL;
  GimpPDBStatusType        status   = GIMP_PDB_EXECUTION_ERROR;
  GimpRunMode              run_mode;
  GFile                   *file;
  gint                     width;
  gint                     height;
  gint                     arg_offset = 0;
  gint                     i;

  run_mode = GIMP_VALUES_GET_ENUM (args, arg_offset++);
  file     = GIMP_VALUES_GET_FILE (args, arg_offset++);
  width    = GIMP_VALUES_GET_INT  (args, arg_offset++);
  height   = GIMP_VALUES_GET_INT  (args, arg_offset++);

  remaining = gimp_value_array_new (gimp_value_array_length (args) - arg_offset);

  for (i = 2 /*arg_offset*/; i < gimp_value_array_length (args); i++)
    {
      GValue *value = gimp_value_array_index (args, i);

      gimp_value_array_append (remaining, value);
    }

  config   = gimp_procedure_create_config (procedure);
  mimetype = (gchar *) gimp_file_procedure_get_mime_types (GIMP_FILE_PROCEDURE (procedure));

  if (mimetype != NULL)
    {
      char *delim;

      mimetype = g_strdup (mimetype);
      mimetype = g_strstrip (mimetype);
      delim = strstr (mimetype, ",");
      if (delim)
        *delim = '\0';
      /* Though docs only writes about the list being comma-separated, our
       * code apparently also split by spaces.
       */
      delim = strstr (mimetype, " ");
      if (delim)
        *delim = '\0';
      delim = strstr (mimetype, "\t");
      if (delim)
        *delim = '\0';

      metadata = gimp_metadata_load_from_file (file, NULL);
      g_free (mimetype);
    }
  else
    {
      flags = GIMP_METADATA_LOAD_NONE;
    }

  if (metadata == NULL)
    metadata = gimp_metadata_new ();

  _gimp_procedure_config_begin_run (config, image, run_mode, remaining);

  return_values = load_proc->run_func (procedure,
                                       run_mode,
                                       file, width, height,
                                       TRUE, TRUE,
                                       metadata, &flags,
                                       config,
                                       load_proc->run_data);

  if (return_values != NULL                       &&
      gimp_value_array_length (return_values) > 0 &&
      G_VALUE_HOLDS_ENUM (gimp_value_array_index (return_values, 0)))
    status = GIMP_VALUES_GET_ENUM (return_values, 0);

  _gimp_procedure_config_end_run (config, status);

  if (status == GIMP_PDB_SUCCESS)
    {
      if (gimp_value_array_length (return_values) < 2 ||
          ! GIMP_VALUE_HOLDS_IMAGE (gimp_value_array_index (return_values, 1)))
        {
          GError *error = NULL;

          status = GIMP_PDB_EXECUTION_ERROR;
          g_set_error (&error, GIMP_PLUG_IN_ERROR, 0,
                       _("This file loading plug-in returned SUCCESS as a status without an image. "
                         "This is a bug in the plug-in code. Contact the plug-in developer."));
          gimp_value_array_unref (return_values);
          return_values = gimp_procedure_new_return_values (procedure, status, error);
        }
      else
        {
          image = GIMP_VALUES_GET_IMAGE (return_values, 1);
        }
    }

  if (image != NULL && metadata != NULL && flags != GIMP_METADATA_LOAD_NONE)
    gimp_image_metadata_load_finish (image, NULL, metadata, flags);

  /* This is debug printing to help plug-in developers figure out best
   * practices.
   */
  plug_in = gimp_procedure_get_plug_in (procedure);
  if (G_OBJECT (config)->ref_count > 1 &&
      _gimp_plug_in_manage_memory_manually (plug_in))
    g_printerr ("%s: ERROR: the GimpSaveProcedureConfig object was refed "
                "by plug-in, it MUST NOT do that!\n", G_STRFUNC);

  g_object_unref (config);
  g_clear_object (&metadata);
  gimp_value_array_unref (remaining);

  return return_values;
}


/*  public functions  */

/**
 * gimp_vector_load_procedure_new:
 * @plug_in:          a #GimpPlugIn.
 * @name:             the new procedure's name.
 * @proc_type:        the new procedure's #GimpPDBProcType.
 * @run_func:         the run function for the new procedure.
 * @run_data:         user data passed to @run_func.
 * @run_data_destroy: (nullable): free function for @run_data, or %NULL.
 *
 * Creates a new load procedure named @name which will call @run_func
 * when invoked.
 *
 * See gimp_procedure_new() for information about @proc_type.
 *
 * Returns: (transfer full): a new #GimpProcedure.
 *
 * Since: 3.0
 **/
GimpProcedure  *
gimp_vector_load_procedure_new (GimpPlugIn            *plug_in,
                                const gchar           *name,
                                GimpPDBProcType        proc_type,
                                GimpRunVectorLoadFunc  run_func,
                                gpointer               run_data,
                                GDestroyNotify         run_data_destroy)
{
  GimpVectorLoadProcedure *procedure;

  g_return_val_if_fail (GIMP_IS_PLUG_IN (plug_in), NULL);
  g_return_val_if_fail (gimp_is_canonical_identifier (name), NULL);
  g_return_val_if_fail (proc_type != GIMP_PDB_PROC_TYPE_INTERNAL, NULL);
  g_return_val_if_fail (proc_type != GIMP_PDB_PROC_TYPE_EXTENSION, NULL);
  g_return_val_if_fail (run_func != NULL, NULL);

  procedure = g_object_new (GIMP_TYPE_VECTOR_LOAD_PROCEDURE,
                            "plug-in",        plug_in,
                            "name",           name,
                            "procedure-type", proc_type,
                            NULL);

  procedure->run_func         = run_func;
  procedure->run_data         = run_data;
  procedure->run_data_destroy = run_data_destroy;

  return GIMP_PROCEDURE (procedure);
}