# Module of TWiki Enterprise Collaboration Platform, http://TWiki.org/
#
# Copyright (C) 2005-2018 Peter Thoeny, peter[at]thoeny.org
# and TWiki Contributors. All Rights Reserved. TWiki Contributors
# are listed in the AUTHORS file in the root of this distribution.
# NOTE: Please extend that file, not this notice.
#
# Additional copyrights apply to some or all of the code in this
# file as follows:
#
# 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. For
# more details read LICENSE in the root of this distribution.
#
# 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.
#
# As per the GPL, removal of this notice is prohibited.
#
# Author: Crawford Currie http://c-dot.co.uk

=begin twiki

---+ package TWiki::If::OP_dollar

=cut

package TWiki::If::OP_dollar;
use base 'TWiki::Query::UnaryOP';

use strict;

sub new {
    my $class = shift;
    return $class->SUPER::new(
        name => '$',
        prec => 600);
}

sub evaluate {
    my $this = shift;
    my $node = shift;
    my $a = $node->{params}->[0];
    my %domain = @_;
    my $session = $domain{tom}->session;
    throw Error::Simple('No context in which to evaluate "'.
                          $a->stringify().'"') unless $session;
    my $text = $a->_evaluate(@_) || '';
    if( $text && defined( $session->{request}->param( $text ))) {
        return $session->{request}->param( $text );
    }

    $text = "%$text%";
    TWiki::expandAllTags($session, \$text,
                         $session->{topicName},
                         $session->{webName});

    return $text || '';
}

1;