package DateTime::Format::Builder::Parser::Dispatch;

{

  $DateTime::Format::Builder::Parser::Dispatch::VERSION = '0.81';

}

use strict;

use warnings;

use vars qw( %dispatch_data );

use Params::Validate qw( CODEREF validate );

use DateTime::Format::Builder::Parser;

{

    no strict 'refs';

    *dispatch_data = *DateTime::Format::Builder::dispatch_data;

    *params        = *DateTime::Format::Builder::Parser::params;

}

DateTime::Format::Builder::Parser->valid_params(

    Dispatch => {

        type => CODEREF,

    }

);

sub create_parser {

    my ( $self, %args ) = @_;

    my $coderef = $args{Dispatch};

    return sub {

        my ( $self, $date, $p, @args ) = @_;

        return unless defined $date;

        my $class = ref($self) || $self;

        my @results = $coderef->($date);

        return unless @results;

        return unless defined $results[0];

        for my $group (@results) {

            my $parser = $dispatch_data{$class}{$group};

            die "Unknown parsing group: $class\n" unless defined $parser;

            my $rv = eval { $parser->parse( $self, $date, $p, @args ) };

            return $rv unless $@ or not defined $rv;

        }

        return;

    };

}

1;

# ABSTRACT: Dispatch parsers by group

__END__

=pod

=head1 NAME

DateTime::Format::Builder::Parser::Dispatch - Dispatch parsers by group

=head1 VERSION

version 0.81

=head1 SYNOPSIS

    package SampleDispatch;

    use DateTime::Format::Builder

    (

	parsers => {

	    parse_datetime => [

		{

		    Dispatch => sub {

			return 'fnerk';

		    }

		}

	    ]

	},

	groups => {

	    fnerk => [

		{

		    regex => qr/^(\d{4})(\d\d)(\d\d)$/,

		    params => [qw( year month day )],

		},

	    ]

	}

    );

=head1 DESCRIPTION

C<Dispatch> adds another parser type to C<Builder> permitting

dispatch of parsing according to group names.

=head1 SPECIFICATION

C<Dispatch> has just one key: C<Dispatch>. The value should be a

reference to a subroutine that returns one of:

=over 4

=item *

C<undef>, meaning no groups could be found.

=item *

An empty list, meaning no groups could be found.

=item *

A single string, meaning: use this group

=item *

A list of strings, meaning: use these groups in this order.

=back

Groups are specified much like the example in the L<SYNOPSIS>.

They follow the same format as when you specify them for methods.

=head1 SIDEEFFECTS

Your group parser can also be a Dispatch parser. Thus you could

potentially end up with an infinitely recursive parser.

=head1 SUPPORT

See L<DateTime::Format::Builder> for details.

=head1 SEE ALSO

C<datetime@perl.org> mailing list.

http://datetime.perl.org/

L<perl>, L<DateTime>,

L<DateTime::Format::Builder>

=head1 AUTHORS

=over 4

=item *

Dave Rolsky <autarch@urth.org>

=item *

Iain Truskett

=back

=head1 COPYRIGHT AND LICENSE

This software is Copyright (c) 2013 by Dave Rolsky.

This is free software, licensed under:

  The Artistic License 2.0 (GPL Compatible)

=cut