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package Dist::Zilla::Plugin::MetaJSON 6.025;
# ABSTRACT: produce a META.json

use Moose;
with 'Dist::Zilla::Role::FileGatherer';
use Moose::Util::TypeConstraints;

# BEGIN BOILERPLATE
use v5.20.0;
use warnings;
use utf8;
no feature 'switch';
use experimental qw(postderef postderef_qq); # This experiment gets mainlined.
# END BOILERPLATE

use namespace::autoclean;

#pod =head1 DESCRIPTION
#pod
#pod This plugin will add a F<META.json> file to the distribution.
#pod
#pod This file is meant to replace the old-style F<META.yml>.  For more information
#pod on this file, see L<Module::Build::API> and L<CPAN::Meta>.
#pod
#pod =attr filename
#pod
#pod If given, parameter allows you to specify an alternate name for the generated
#pod file.  It defaults, of course, to F<META.json>.
#pod
#pod =cut

has filename => (
  is  => 'ro',
  isa => 'Str',
  default => 'META.json',
);

#pod =attr version
#pod
#pod This parameter lets you pick what version of the spec to use when generating
#pod the output.  It defaults to 2 at present, but may be updated to new specs as
#pod they are released and adopted.
#pod
#pod If you want a fixed version, specify it.
#pod
#pod =cut

my $version_type = subtype(
    as 'Num',
    where { $_ >= 2 },
    message { "MetaJSON version must be 2 or greater" },
);

has version => (
  is  => 'ro',
  isa => $version_type,
  default => '2',
);

sub gather_files {
  my ($self, $arg) = @_;

  my $zilla = $self->zilla;

  require JSON::MaybeXS;
  require Dist::Zilla::File::FromCode;
  require CPAN::Meta::Converter;
  CPAN::Meta::Converter->VERSION(2.101550); # improved downconversion
  require CPAN::Meta::Validator;
  CPAN::Meta::Validator->VERSION(2.101550); # improved downconversion

  my $file  = Dist::Zilla::File::FromCode->new({
    name => $self->filename,
    encoding => 'ascii',
    code_return_type => 'text',
    code => sub {
      my $distmeta  = $zilla->distmeta;

      my $validator = CPAN::Meta::Validator->new($distmeta);

      unless ($validator->is_valid) {
        my $msg = "Invalid META structure.  Errors found:\n";
        $msg .= join( "\n", $validator->errors );
        $self->log_fatal($msg);
      }

      my $converter = CPAN::Meta::Converter->new($distmeta);
      my $output    = $converter->convert(version => $self->version);

      my $backend = JSON::MaybeXS::JSON();
      $output->{x_serialization_backend} = sprintf '%s version %s',
            $backend, $backend->VERSION;

      JSON::MaybeXS->new(canonical => 1, pretty => 1, ascii => 1)->encode($output)
      . "\n";
    },
  });

  $self->add_file($file);
  return;
}

__PACKAGE__->meta->make_immutable;
1;

#pod =head1 SEE ALSO
#pod
#pod Core Dist::Zilla plugins:
#pod L<@Basic|Dist::Zilla::PluginBundle::Basic>,
#pod L<Manifest|Dist::Zilla::Plugin::Manifest>.
#pod
#pod Dist::Zilla roles:
#pod L<FileGatherer|Dist::Zilla::Role::FileGatherer>.
#pod
#pod Other modules:
#pod L<CPAN::Meta>,
#pod L<CPAN::Meta::Spec>, L<JSON::MaybeXS>.
#pod
#pod =cut

__END__

=pod

=encoding UTF-8

=head1 NAME

Dist::Zilla::Plugin::MetaJSON - produce a META.json

=head1 VERSION

version 6.025

=head1 DESCRIPTION

This plugin will add a F<META.json> file to the distribution.

This file is meant to replace the old-style F<META.yml>.  For more information
on this file, see L<Module::Build::API> and L<CPAN::Meta>.

=head1 PERL VERSION

This module should work on any version of perl still receiving updates from
the Perl 5 Porters.  This means it should work on any version of perl released
in the last two to three years.  (That is, if the most recently released
version is v5.40, then this module should work on both v5.40 and v5.38.)

Although it may work on older versions of perl, no guarantee is made that the
minimum required version will not be increased.  The version may be increased
for any reason, and there is no promise that patches will be accepted to lower
the minimum required perl.

=head1 ATTRIBUTES

=head2 filename

If given, parameter allows you to specify an alternate name for the generated
file.  It defaults, of course, to F<META.json>.

=head2 version

This parameter lets you pick what version of the spec to use when generating
the output.  It defaults to 2 at present, but may be updated to new specs as
they are released and adopted.

If you want a fixed version, specify it.

=head1 SEE ALSO

Core Dist::Zilla plugins:
L<@Basic|Dist::Zilla::PluginBundle::Basic>,
L<Manifest|Dist::Zilla::Plugin::Manifest>.

Dist::Zilla roles:
L<FileGatherer|Dist::Zilla::Role::FileGatherer>.

Other modules:
L<CPAN::Meta>,
L<CPAN::Meta::Spec>, L<JSON::MaybeXS>.

=head1 AUTHOR

Ricardo SIGNES 😏 <rjbs@semiotic.systems>

=head1 COPYRIGHT AND LICENSE

This software is copyright (c) 2022 by Ricardo SIGNES.

This is free software; you can redistribute it and/or modify it under
the same terms as the Perl 5 programming language system itself.

=cut