# The GIMP -- an 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 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.

# "Perlized" from C source by Manish Singh <yosh@gimp.org>

# The defs

sub image_undo_group_start {
    $blurb = 'Starts a group undo.';

    $help = <<'HELP';
This function is used to start a group undo--necessary for logically combining
two or more undo operations into a single operation. This call must be used in
conjunction with a 'gimp-image-undo-group-end' call.
HELP

    &std_pdb_misc;
    $date = '1997';

    @inargs = ( &std_image_arg );
    $inargs[0]->{desc} = 'The ID of the image in which to open an undo group';

    %invoke = ( headers => [ qw("core/gimp.h" "plug-in/plug-in.h") ],
                vars => [ 'gchar *undo_desc = NULL' ],
                code => <<CODE
{
  if (gimp->current_plug_in)
    undo_desc = plug_in_get_undo_desc (gimp->current_plug_in);

  gimp_image_undo_group_start (gimage, GIMP_UNDO_GROUP_MISC, undo_desc);

  if (undo_desc)
    g_free (undo_desc);
}
CODE
    );
}

sub image_undo_group_end {
    $blurb = 'Finish a group undo.';

    $help = <<'HELP';
This function must be called once for each 'gimp-image-undo-group-start' call
that is made.
HELP

    &std_pdb_misc;
    $date = '1997';

    @inargs = ( &std_image_arg );
    $inargs[0]->{desc} = 'The ID of the image in which to close an undo group';

    %invoke = ( code => 'gimp_image_undo_group_end (gimage);' );
}

sub image_undo_is_enabled {
    $blurb = "Check if the image's undo stack is enabled.";

    $help = <<'HELP';
This procedure checks if the image's undo stack is currently enabled or
disabled.  This is useful when several plugins or scripts call each other
and want to check if their caller has already used 'gimp_image_undo_disable'
or 'gimp_image_undo_freeze'.
HELP

    $author = $copyright = 'Raphael Quinet';
    $date = '1999';

    @inargs = ( &std_image_arg );

    @outargs = (
	{ name => 'enabled', type => 'boolean', init => 1,
	  desc => 'True if undo is enabled for this image' }
    );

    %invoke = ( code => 'enabled = gimp_image_undo_is_enabled (gimage);' );
}

sub image_undo_disable {
    $blurb = "Disable the image's undo stack.";

    $help = <<'HELP';
This procedure disables the image's undo stack, allowing subsequent operations
to ignore their undo steps. This is generally called in conjunction with
'gimp_image_undo_enable' to temporarily disable an image undo stack. This is
advantageous because saving undo steps can be time and memory intensive.
HELP

    &std_pdb_misc;

    @inargs = ( &std_image_arg );

    @outargs = (
	{ name => 'disabled', type => 'boolean',
	  desc => 'True if the image undo has been disabled',
	  alias => 'success ? TRUE : FALSE', no_declare => 1 }
    );

    %invoke = ( code => 'success = gimp_image_undo_disable (gimage);' );
}

sub image_undo_enable {
    $blurb = "Enable the image's undo stack.";

    $help = <<'HELP';
This procedure enables the image's undo stack, allowing subsequent operations
to store their undo steps. This is generally called in conjunction with
'gimp_image_undo_disable' to temporarily disable an image undo stack.
HELP

    &std_pdb_misc;

    @inargs = ( &std_image_arg );

    @outargs = (
	{ name => 'enabled', type => 'boolean',
	  desc => 'True if the image undo has been enabled',
	  alias => 'success ? TRUE : FALSE', no_declare => 1 }
    );

    %invoke = ( code => 'success = gimp_image_undo_enable (gimage);' );
}

sub image_undo_freeze {
    $blurb = "Freeze the image's undo stack.";

    $author = $copyright = 'Adam D. Moss';
    $date = '1999';

    $help = <<'HELP';
This procedure freezes the image's undo stack, allowing subsequent operations
to ignore their undo steps.  This is generally called in conjunction with 
'gimp_image_undo_thaw' to temporarily disable an image undo stack.  This is 
advantageous because saving undo steps can be time and memory intensive.  
'gimp_image_undo_{freeze,thaw}' and 'gimp_image_undo_{disable,enable}' differ 
in that the former does not free up all undo steps when undo is thawed, so is 
more suited to interactive in-situ previews.  It is important in this case 
that the image is back to the same state it was frozen in before thawing, else 
'undo' behaviour is undefined.
HELP

    @inargs = ( &std_image_arg );

    @outargs = (
	{ name => 'frozen', type => 'boolean',
	  desc => 'True if the image undo has been frozen',
	  alias => 'success ? TRUE : FALSE', no_declare => 1 }
    );

    %invoke = ( code => 'success = gimp_image_undo_freeze (gimage);' );
}

sub image_undo_thaw {
    $blurb = "Thaw the image's undo stack.";

    $author = $copyright = 'Adam D. Moss';
    $date = '1999';

    $help = <<'HELP';
This procedure thaws the image's undo stack, allowing subsequent operations to 
store their undo steps. This is generally called in conjunction with 
'gimp_image_undo_freeze' to temporarily freeze an image undo stack.  
'gimp_image_undo_thaw' does NOT free the undo stack as
'gimp_image_undo_enable' does, so is suited for situations where one wishes to 
leave the undo stack in the same state in which one found it despite 
non-destructively playing with the image in the meantime.  An example would be 
in-situ plugin previews.  Balancing freezes and thaws and ensuring image 
consistancy is the responsibility of the caller.
HELP

    @inargs = ( &std_image_arg );

    @outargs = (
	{ name => 'thawed', type => 'boolean',
	  desc => 'True if the image undo has been thawed',
	  alias => 'success ? TRUE : FALSE', no_declare => 1 }
    );

    %invoke = ( code => 'success = gimp_image_undo_thaw (gimage);' );
}

@headers = qw("core/gimpimage-undo.h");

@procs = qw(image_undo_group_start image_undo_group_end
            image_undo_is_enabled
            image_undo_disable image_undo_enable
            image_undo_freeze image_undo_thaw);
%exports = (app => [@procs], lib => [@procs]);

$desc = 'Undo';

1;