package Tree::Transform;
use Moose;
use Sub::Exporter;
use Params::Validate ':all';

our $VERSION='0.1';

Sub::Exporter::setup_exporter({
    exports => [qw(tree_rule new_transformer)],
    groups => {
        default => [ 'tree_rule',
                     'new_transformer' => {-as => 'new'} ],
    }
});

sub _rules_store {
    no strict 'refs';
    if (!defined *{$_[0].'::_tree_transform_rules'}{HASH}) {
        *{$_[0].'::_tree_transform_rules'}={};
    }
    return *{$_[0].'::_tree_transform_rules'}{HASH};
}

sub tree_rule {
    my (%args)=validate(@_, {
        match => { type => SCALAR, optional => 1 },
        action => { type => CODEREF },
        name => { type => SCALAR, optional => 1},
        priority => { type => SCALAR, default => 1 },
    });

    # TODO at least one of 'name' and 'match' must be specified

    my $store=_rules_store(scalar caller);

    push @{$store->{by_match}},\%args;
    if ($args{name}) {
        push @{$store->{by_name}{$args{name}}},\%args;
    }

    return;
}

sub new_transformer {
}

__PACKAGE__->meta->make_immutable;no Moose;
__END__

=head1 NAME

Tree::Transform - transform tree data, like XSLT but in Perl

=head1 AUTHOR

Gianni Ceccarelli <dakkar@thenautilus.net>

=cut