# 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.
#
# 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::Query::OP_ref

=cut

package TWiki::Query::OP_ref;
use base 'TWiki::Query::BinaryOP';

use strict;
use Error qw( :try );

sub new {
    my $class = shift;
    return $class->SUPER::new( name => '/', prec => 700 );
}

sub evaluate {
    my $this = shift;
    my $pnode = shift;
    my %domain = @_;

    my $session = $domain{tom}->session;
    my $topic = $domain{tom}->topic;

    my $a = $pnode->{params}[0];
    my $node = $a->evaluate( @_ );
    return undef unless defined $node;
    if( ref($node) eq 'HASH') {
        return undef;
    }
    if( !( ref($node) eq 'ARRAY' )) {
        $node = [ $node ];
    }
    my @result;
    foreach my $v (@$node) {
        next if $v !~ /^($TWiki::regex{webNameRegex}\.)*$TWiki::regex{wikiWordRegex}$/;

        # Has to be relative to the web of the topic we are querying
        my( $w, $t ) = $session->normalizeWebTopicName(
            $session->{webName}, $v );
        my $result = undef;
        try {
            my $submeta = $domain{tom}->getMetaFor( $w, $t );
            my $b = $pnode->{params}[1];
            my $res = $b->evaluate( tom=>$submeta, data=>$submeta );
            if( ref($res) eq 'ARRAY') {
                push(@result, @$res);
            } else {
                push(@result, $res);
            }
        } catch Error::Simple with {
        };
    }
    return undef unless scalar( @result );
    return $result[0] if scalar(@result) == 1;
    return \@result;
}

1;