gboolean
gimp_pdb_item_is_in_same_tree (GimpItem   *item,
                               GimpItem   *item2,
                               GimpImage  *image,
                               GError    **error)
{
  g_return_val_if_fail (GIMP_IS_ITEM (item), FALSE);
  g_return_val_if_fail (GIMP_IS_ITEM (item2), FALSE);
  g_return_val_if_fail (image == NULL || GIMP_IS_IMAGE (image), FALSE);
  g_return_val_if_fail (error == NULL || *error == NULL, FALSE);

  if (! gimp_pdb_item_is_in_tree (item, image, FALSE, error) ||
      ! gimp_pdb_item_is_in_tree (item2, image, FALSE, error))
    return FALSE;

  if (gimp_item_get_tree (item) != gimp_item_get_tree (item2))
    {
      g_set_error (error, GIMP_PDB_ERROR, GIMP_PDB_ERROR_INVALID_ARGUMENT,
                   _("Items '%s' (%d) and '%s' (%d) cannot be used "
                     "because they are not part of the same item tree"),
                   gimp_object_get_name (item),
                   gimp_item_get_ID (item),
                   gimp_object_get_name (item2),
                   gimp_item_get_ID (item2));
      return FALSE;
    }

  return TRUE;
}

gint
gimp_item_get_ID (GimpItem *item)
{
  g_return_val_if_fail (GIMP_IS_ITEM (item), -1);

  return item->ID;
}

GimpTattoo
gimp_item_get_tattoo (const GimpItem *item)
{
  g_return_val_if_fail (GIMP_IS_ITEM (item), 0);

  return item->tattoo;
}

/**
 * gimp_item_is_removed:
 * @item: the #GimpItem to check.
 *
 * Returns: %TRUE if the 'removed' flag is set for @item, %FALSE otherwise.
 */
gboolean
gimp_item_is_removed (const GimpItem *item)
{
  g_return_val_if_fail (GIMP_IS_ITEM (item), FALSE);

  return item->removed;
}

gboolean
gimp_pdb_item_is_modifyable (GimpItem           *item,
                             GimpPDBItemModify   modify,
                             GError            **error)
{
  g_return_val_if_fail (GIMP_IS_ITEM (item), FALSE);
  g_return_val_if_fail (error == NULL || *error == NULL, FALSE);

  if ((modify & GIMP_PDB_ITEM_CONTENT) && gimp_item_is_content_locked (item))
    {
      g_set_error (error, GIMP_PDB_ERROR, GIMP_PDB_ERROR_INVALID_ARGUMENT,
                   _("Item '%s' (%d) cannot be modified because its "
                     "contents are locked"),
                   gimp_object_get_name (item),
                   gimp_item_get_ID (item));
      return FALSE;
    }

  if ((modify & GIMP_PDB_ITEM_POSITION) && gimp_item_is_position_locked (item))
    {
      g_set_error (error, GIMP_PDB_ERROR, GIMP_PDB_ERROR_INVALID_ARGUMENT,
                   _("Item '%s' (%d) cannot be modified because its "
                     "position and size are locked"),
                   gimp_object_get_name (item),
                   gimp_item_get_ID (item));
      return FALSE;
    }

  return TRUE;
}

/**
 * gimp_item_width:
 * @item: The #GimpItem to check.
 *
 * Returns: The width of the item.
 */
gint
gimp_item_width (const GimpItem *item)
{
  g_return_val_if_fail (GIMP_IS_ITEM (item), -1);

  return item->width;
}

void
gimp_item_linked_transform (GimpItem               *item,
                            GimpContext            *context,
                            const GimpMatrix3      *matrix,
                            GimpTransformDirection  direction,
                            GimpInterpolationType   interpolation_type,
                            GimpTransformResize     clip_result,
                            GimpProgress           *progress)
{
  GList *list;

  g_return_if_fail (GIMP_IS_ITEM (item));
  g_return_if_fail (GIMP_IS_CONTEXT (context));
  g_return_if_fail (gimp_item_get_linked (item) == TRUE);
  g_return_if_fail (gimp_item_is_attached (item));
  g_return_if_fail (progress == NULL || GIMP_IS_PROGRESS (progress));

  list = gimp_image_item_list_get_list (gimp_item_get_image (item), item,
                                        GIMP_ITEM_TYPE_ALL,
                                        GIMP_ITEM_SET_LINKED);

  list = gimp_image_item_list_filter (item, list, TRUE, FALSE);

  gimp_image_item_list_transform (gimp_item_get_image (item), list, context,
                                  matrix, direction,
                                  interpolation_type,
                                  clip_result, progress);

  g_list_free (list);
}

/**
 * gimp_item_is_attached:
 * @item: The #GimpItem to check.
 *
 * Returns: %TRUE if the item is attached to an image, %FALSE otherwise.
 */
gboolean
gimp_item_is_attached (GimpItem *item)
{
  g_return_val_if_fail (GIMP_IS_ITEM (item), FALSE);

  return GIMP_ITEM_GET_CLASS (item)->is_attached (item);
}

void
gimp_item_transform (GimpItem               *item,
                     GimpContext            *context,
                     const GimpMatrix3      *matrix,
                     GimpTransformDirection  direction,
                     GimpInterpolationType   interpolation,
                     gint                    recursion_level,
                     GimpTransformResize     clip_result,
                     GimpProgress           *progress)
{
  GimpItemClass *item_class;
  GimpImage     *image;

  g_return_if_fail (GIMP_IS_ITEM (item));
  g_return_if_fail (gimp_item_is_attached (item));
  g_return_if_fail (GIMP_IS_CONTEXT (context));
  g_return_if_fail (matrix != NULL);
  g_return_if_fail (progress == NULL || GIMP_IS_PROGRESS (progress));

  item_class = GIMP_ITEM_GET_CLASS (item);
  image = gimp_item_get_image (item);

  gimp_image_undo_group_start (image, GIMP_UNDO_GROUP_TRANSFORM,
                               item_class->transform_desc);

  item_class->transform (item, context, matrix, direction, interpolation,
                         recursion_level, clip_result, progress);

  gimp_image_undo_group_end (image);
}

/**
 * gimp_item_height:
 * @item: The #GimpItem to check.
 *
 * Returns: The height of the item.
 */
gint
gimp_item_height (const GimpItem *item)
{
  g_return_val_if_fail (GIMP_IS_ITEM (item), -1);

  return item->height;
}

void
gimp_item_resize (GimpItem    *item,
                  GimpContext *context,
                  gint         new_width,
                  gint         new_height,
                  gint         offset_x,
                  gint         offset_y)
{
  GimpItemClass *item_class;
  GimpImage     *image;

  g_return_if_fail (GIMP_IS_ITEM (item));
  g_return_if_fail (GIMP_IS_CONTEXT (context));

  if (new_width < 1 || new_height < 1)
    return;

  item_class = GIMP_ITEM_GET_CLASS (item);
  image = gimp_item_get_image (item);

  if (gimp_item_is_attached (item))
    gimp_image_undo_group_start (image, GIMP_UNDO_GROUP_ITEM_RESIZE,
                                 item_class->resize_desc);

  item_class->resize (item, context, new_width, new_height, offset_x, offset_y);

  if (gimp_item_is_attached (item))
    gimp_image_undo_group_end (image);
}

void
gimp_item_rotate (GimpItem         *item,
                  GimpContext      *context,
                  GimpRotationType  rotate_type,
                  gdouble           center_x,
                  gdouble           center_y,
                  gboolean          clip_result)
{
  GimpItemClass *item_class;
  GimpImage     *image;

  g_return_if_fail (GIMP_IS_ITEM (item));
  g_return_if_fail (gimp_item_is_attached (item));
  g_return_if_fail (GIMP_IS_CONTEXT (context));

  item_class = GIMP_ITEM_GET_CLASS (item);
  image = gimp_item_get_image (item);

  gimp_image_undo_group_start (image, GIMP_UNDO_GROUP_TRANSFORM,
                               item_class->rotate_desc);

  item_class->rotate (item, context, rotate_type, center_x, center_y,
                      clip_result);

  gimp_image_undo_group_end (image);
}

void
gimp_item_scale (GimpItem              *item,
                 gint                   new_width,
                 gint                   new_height,
                 gint                   new_offset_x,
                 gint                   new_offset_y,
                 GimpInterpolationType  interpolation,
                 GimpProgress          *progress)
{
  GimpItemClass *item_class;
  GimpImage     *image;

  g_return_if_fail (GIMP_IS_ITEM (item));
  g_return_if_fail (progress == NULL || GIMP_IS_PROGRESS (progress));

  if (new_width < 1 || new_height < 1)
    return;

  item_class = GIMP_ITEM_GET_CLASS (item);
  image = gimp_item_get_image (item);

  if (gimp_item_is_attached (item))
    gimp_image_undo_group_start (image, GIMP_UNDO_GROUP_ITEM_SCALE,
                                 item_class->scale_desc);

  item_class->scale (item, new_width, new_height, new_offset_x, new_offset_y,
                     interpolation, progress);

  if (gimp_item_is_attached (item))
    gimp_image_undo_group_end (image);
}

/**
 * gimp_item_scale_by_factors:
 * @item:     Item to be transformed by explicit width and height factors.
 * @w_factor: scale factor to apply to width and horizontal offset
 * @h_factor: scale factor to apply to height and vertical offset
 * @interpolation:
 * @progress:
 *
 * Scales item dimensions and offsets by uniform width and
 * height factors.
 *
 * Use gimp_item_scale_by_factors() in circumstances when the same
 * width and height scaling factors are to be uniformly applied to a
 * set of items. In this context, the item's dimensions and offsets
 * from the sides of the containing image all change by these
 * predetermined factors. By fiat, the fixed point of the transform is
 * the upper left hand corner of the image. Returns #FALSE if a
 * requested scale factor is zero or if a scaling zero's out a item
 * dimension; returns #TRUE otherwise.
 *
 * Use gimp_item_scale() in circumstances where new item width
 * and height dimensions are predetermined instead.
 *
 * Side effects: Undo set created for item. Old item imagery
 *               scaled & painted to new item tiles.
 *
 * Returns: #TRUE, if the scaled item has positive dimensions
 *          #FALSE if the scaled item has at least one zero dimension
 **/
gboolean
gimp_item_scale_by_factors (GimpItem              *item,
                            gdouble                w_factor,
                            gdouble                h_factor,
                            GimpInterpolationType  interpolation,
                            GimpProgress          *progress)
{
  gint new_width, new_height;
  gint new_offset_x, new_offset_y;

  g_return_val_if_fail (GIMP_IS_ITEM (item), FALSE);
  g_return_val_if_fail (progress == NULL || GIMP_IS_PROGRESS (progress), FALSE);

  if (w_factor == 0.0 || h_factor == 0.0)
    {
      g_warning ("%s: requested width or height scale equals zero", G_STRFUNC);
      return FALSE;
    }

  new_offset_x = ROUND (w_factor * (gdouble) item->offset_x);
  new_offset_y = ROUND (h_factor * (gdouble) item->offset_y);
  new_width    = ROUND (w_factor * (gdouble) gimp_item_width  (item));
  new_height   = ROUND (h_factor * (gdouble) gimp_item_height (item));

  if (new_width != 0 && new_height != 0)
    {
      gimp_item_scale (item,
                       new_width, new_height,
                       new_offset_x, new_offset_y,
                       interpolation, progress);
      return TRUE;
    }

  return FALSE;
}

void
gimp_item_parasite_detach (GimpItem    *item,
                           const gchar *name)
{
  const GimpParasite *parasite;

  g_return_if_fail (GIMP_IS_ITEM (item));
  g_return_if_fail (name != NULL);

  parasite = gimp_parasite_list_find (item->parasites, name);

  if (! parasite)
    return;

  if (gimp_parasite_is_undoable (parasite))
    {
      gimp_image_undo_push_item_parasite_remove (item->image,
                                                 _("Remove Parasite from Item"),
                                                 item,
                                                 gimp_parasite_name (parasite));
    }
  else if (gimp_parasite_is_persistent (parasite))
    {
      gimp_image_undo_push_cantundo (item->image,
                                     _("Remove Parasite from Item"));
    }

  gimp_parasite_list_remove (item->parasites, name);
}

/**
 * gimp_item_translate:
 * @item:      The #GimpItem to move.
 * @offset_x:  Increment to the X offset of the item.
 * @offset_y:  Increment to the Y offset of the item.
 * @push_undo: If #TRUE, create an entry in the image's undo stack
 *             for this action.
 *
 * Adds the specified increments to the X and Y offsets for the item.
 */
void
gimp_item_translate (GimpItem *item,
                     gint      offset_x,
                     gint      offset_y,
                     gboolean  push_undo)
{
  GimpItemClass *item_class;
  GimpImage     *image;

  g_return_if_fail (GIMP_IS_ITEM (item));

  item_class = GIMP_ITEM_GET_CLASS (item);
  image = gimp_item_get_image (item);

  if (! gimp_item_is_attached (item))
    push_undo = FALSE;

  if (push_undo)
    gimp_image_undo_group_start (image, GIMP_UNDO_GROUP_ITEM_DISPLACE,
                                 item_class->translate_desc);

  item_class->translate (item, offset_x, offset_y, push_undo);

  if (push_undo)
    gimp_image_undo_group_end (image);
}

gboolean
gimp_pdb_item_is_attached (GimpItem           *item,
                           GimpImage          *image,
                           GimpPDBItemModify   modify,
                           GError            **error)
{
  g_return_val_if_fail (GIMP_IS_ITEM (item), FALSE);
  g_return_val_if_fail (image == NULL || GIMP_IS_IMAGE (image), FALSE);
  g_return_val_if_fail (error == NULL || *error == NULL, FALSE);

  if (! gimp_item_is_attached (item))
    {
      g_set_error (error, GIMP_PDB_ERROR, GIMP_PDB_ERROR_INVALID_ARGUMENT,
                   _("Item '%s' (%d) cannot be used because it has not "
                     "been added to an image"),
                   gimp_object_get_name (item),
                   gimp_item_get_ID (item));
      return FALSE;
    }

  if (image && image != gimp_item_get_image (item))
    {
      g_set_error (error, GIMP_PDB_ERROR, GIMP_PDB_ERROR_INVALID_ARGUMENT,
                   _("Item '%s' (%d) cannot be used because it is "
                     "attached to another image"),
                   gimp_object_get_name (item),
                   gimp_item_get_ID (item));
      return FALSE;
    }

  return gimp_pdb_item_is_modifyable (item, modify, error);
}

GimpImage *
gimp_item_get_image (const GimpItem *item)
{
  g_return_val_if_fail (GIMP_IS_ITEM (item), NULL);

  return item->image;
}

gboolean
gimp_pdb_item_is_in_tree (GimpItem           *item,
                          GimpImage          *image,
                          GimpPDBItemModify   modify,
                          GError            **error)
{
  g_return_val_if_fail (GIMP_IS_ITEM (item), FALSE);
  g_return_val_if_fail (image == NULL || GIMP_IS_IMAGE (image), FALSE);
  g_return_val_if_fail (error == NULL || *error == NULL, FALSE);

  if (! gimp_pdb_item_is_attached (item, image, modify, error))
    return FALSE;

  if (! gimp_item_get_tree (item))
    {
      g_set_error (error, GIMP_PDB_ERROR, GIMP_PDB_ERROR_INVALID_ARGUMENT,
                   _("Item '%s' (%d) cannot be used because it is not "
                     "a direct child of an item tree"),
                   gimp_object_get_name (item),
                   gimp_item_get_ID (item));
      return FALSE;
    }

  return TRUE;
}

void
gimp_item_linked_flip (GimpItem            *item,
                       GimpContext         *context,
                       GimpOrientationType  flip_type,
                       gdouble              axis,
                       gboolean             clip_result)
{
  GList *list;

  g_return_if_fail (GIMP_IS_ITEM (item));
  g_return_if_fail (GIMP_IS_CONTEXT (context));
  g_return_if_fail (gimp_item_get_linked (item) == TRUE);
  g_return_if_fail (gimp_item_is_attached (item));

  list = gimp_image_item_list_get_list (gimp_item_get_image (item), item,
                                        GIMP_ITEM_TYPE_ALL,
                                        GIMP_ITEM_SET_LINKED);

  list = gimp_image_item_list_filter (item, list, TRUE, FALSE);

  gimp_image_item_list_flip (gimp_item_get_image (item), list, context,
                             flip_type, axis, clip_result);

  g_list_free (list);
}