package MooseX::AbstractFactory;

use Moose ();
use Moose::Exporter;
use MooseX::AbstractFactory::Role;
use MooseX::AbstractFactory::Meta::Class;

our $VERSION = '0.3.2';
$VERSION = eval $VERSION;
our $AUTHORITY = 'cpan:PENFOLD';

# syntactic sugar for various tricks

Moose::Exporter->setup_import_methods(
    with_caller => [ 'implementation_does', 'implementation_class_via' ], 
    also => 'Moose',
);

sub implementation_does {
    my ($caller, @roles) = @_;
    
    $caller->meta->implementation_roles(\@roles);
    return;
}

sub implementation_class_via {
    my ($caller, $code) = @_;
    
    $caller->meta->implementation_class_maker($code);
    return;
}

sub init_meta {
    my ($class, %options) = @_;

    Moose->init_meta( %options, metaclass => 'MooseX::AbstractFactory::Meta::Class' );
    
    Moose::Util::MetaRole::apply_base_class_roles(
        for_class => $options{for_class},
        roles     => ['MooseX::AbstractFactory::Role'],
    );

    return $options{for_class}->meta();
}

1;    # Magic true value required at end of module
__END__

=head1 NAME

MooseX::AbstractFactory - AbstractFactory behaviour as a Moose extension


=head1 SYNOPSIS

	package My::Factory;
	use MooseX::AbstractFactory;
	
	# optional role(s) that define what the implementations should implement

	implementation_does qw/My::Factory::Implementation::Requires/];
	implementation_class_via sub { 'My::Implementation::' . shift };
	
	# -------------------------------------------------------------
	package My::Implementation::One;
	use Moose;
	
	has connection => (is => 'ro', isa => 'Str');

	sub tweak_connection {
		...
	}
	
	
	# -------------------------------------------------------------	
	package My::Factory::Implementation::Requires;
	use Moose::Role;
	requires 'tweak_connection';

	
	# -------------------------------------------------------------
	package main;
	use My::Factory;
	
	my $imp = My::Factory->create('One',
		{ connection => 'Type1' },
	);

	

=head1 DESCRIPTION

Implements an AbstractFactory as a Moose extension 


=head1 SUBROUTINES/METHODS 

=head2 create()

Returns an instance of the requested implementation.

    use MooseX::AbstractFactory;
    
	my $imp = My::Factory->create(
		'Implementation',
		{ connection => 'Type1' },
	);
	
=head2 implementation_does

Syntactic sugar to define a list of roles each implementation must consume.

=head2 implementation_class_via

Syntactic sugar to provide a sub to generate the implementation class name:
e.g.:

    use MooseX::AbstractFactory;
    implementation_class_via sub { 'My::Implementation::' . shift };

and then

    my $imp = My::Factory->create("ClassA");
    
    # $imp->isa "My::Implementation::ClassA"
    
The default behaviour is to prepend the factory class name, so in the above
example (without the implementation_class_via) the implementation class would 
be "My::Factory::ClassA".

=head1 DIAGNOSTICS

=over

=item C<< No implementation provided >>

If the factory class's new() method doesn't get an implementation passed, 
then it will die with the above error.

=item C<< Invalid implementation class %s: %s" >>

The implementation passed to the factory class mapped to a class that doesn't exist.

=back

=head1 CONFIGURATION AND ENVIRONMENT
 
MooseX::AbstractFactory requires no configuration files or environment variables.


=head1 DEPENDENCIES

Moose.


=head1 INCOMPATIBILITIES

None reported.


=head1 BUGS AND LIMITATIONS

No bugs have been reported. Yet.

Please report any bugs or feature requests to C<mike@altrion.org>, or via RT.


=head1 AUTHOR

Mike Whitaker  C<< <mike@altrion.org> >>

With thanks to Dave Rolsky for the suggestions for syntactic sugar.

=head1 LICENSE AND COPYRIGHT

Copyright (c) 2007-8, Mike Whitaker C<< <mike@altrion.org> >>.

This module is free software; you can redistribute it and/or
modify it under the same terms as Perl itself. See L<perlartistic>.

=head1 DISCLAIMER OF WARRANTY

BECAUSE THIS SOFTWARE IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
FOR THE SOFTWARE, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN
OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
PROVIDE THE SOFTWARE "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER
EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE
ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE SOFTWARE IS WITH
YOU. SHOULD THE SOFTWARE PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL
NECESSARY SERVICING, REPAIR, OR CORRECTION.

IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
REDISTRIBUTE THE SOFTWARE AS PERMITTED BY THE ABOVE LICENCE, BE
LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL,
OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE
THE SOFTWARE (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING
RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A
FAILURE OF THE SOFTWARE TO OPERATE WITH ANY OTHER SOFTWARE), EVEN IF
SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
SUCH DAMAGES.