package Data::MultiValued::AttributeTrait::Tags;
use Moose::Role;
use namespace::autoclean;
use Data::MultiValued::Tags;
with 'Data::MultiValued::AttributeTrait';

# ABSTRACT: attribute traits for attributes holding tagged values

=head1 SYNOPSIS

  package My::Class;
  use Moose;
  use Data::MultiValued::AttributeTrait::Tags;

  has stuff => (
    is => 'rw',
    isa => 'Int',
    traits => ['MultiValued::Tags'],
    predicate => 'has_stuff',
    multi_accessor => 'stuff_tagged',
    multi_predicate => 'has_stuff_tagged',
  );

=head1 DESCRIPTION

This role consumes L<Data::MultiValued::AttributeTrait> and
specialises it to use L<Data::MultiValued::Tags> as multi-value
storage:

=head2 C<multivalue_storage_class>

Returns C<'Data::MultiValued::Tags'>.

=head2 C<opts_to_pass_set>

Returns C<('tag')>.

=head2 C<opts_to_pass_get>

Returns C<('tag')>.

=head2 C<all_tags>

  my @tags = $obj->meta->get_attribute('my_attr')->all_tags($obj);

Returns a list of all values for which C<<
$obj->has_my_attr_multi({tag=>$tag}) >> would return true.

=cut

sub multivalue_storage_class { 'Data::MultiValued::Tags' };
sub opts_to_pass_set { qw(tag) }
sub opts_to_pass_get { qw(tag) }

sub all_tags {
    my ($self,$instance) = @_;

    my $storage = $self->get_full_storage($instance);
    return () unless $storage;

    my @tags = $storage->_storage->all_tags;
    if ($storage->_storage->_has_default_tag) {
        push @tags,undef;
    }
    return @tags;
}

package Moose::Meta::Attribute::Custom::Trait::MultiValued::Tags;{
sub register_implementation { 'Data::MultiValued::AttributeTrait::Tags' }
}

1;