use strict;
use warnings;
package Dist::Zilla::App::Command::listdeps;
# ABSTRACT: print your distribution's prerequisites
$Dist::Zilla::App::Command::listdeps::VERSION = '5.035';
use Dist::Zilla::App -command;

#pod =head1 SYNOPSIS
#pod
#pod   $ dzil listdeps | cpan
#pod
#pod =head1 DESCRIPTION
#pod
#pod This is a command plugin for L<Dist::Zilla>. It provides the C<listdeps>
#pod command, which prints your distribution's prerequisites. You could pipe that
#pod list to a CPAN client like L<cpan> to install all of the dependencies in one
#pod quick go.
#pod
#pod =head1 OPTIONS
#pod
#pod =head2 --author
#pod
#pod Include author dependencies (those listed under C<develop_requires>).
#pod
#pod =head2 --missing
#pod
#pod List only dependencies which are unsatisfied.
#pod
#pod =head2 --versions
#pod
#pod Also display the required versions of listed modules.
#pod
#pod =head2 --json
#pod
#pod Lists all prerequisites in JSON format, as they would appear in META.json
#pod (broken out into phases and types)
#pod
#pod =head1 ACKNOWLEDGEMENTS
#pod
#pod This code was originally more or less a direct copy of Marcel Gruenauer (hanekomu)
#pod Dist::Zilla::App::Command::prereqs, updated to work with the Dist::Zilla v2
#pod API.
#pod
#pod =cut

use Try::Tiny;

sub abstract { "print your distribution's prerequisites" }

sub opt_spec {
  [ 'author', 'include author dependencies' ],
  [ 'missing', 'list only the missing dependencies' ],
  [ 'versions', 'include required version numbers in listing' ],
  [ 'json', 'list dependencies by phase, in JSON format' ],
  [ 'omit-core=s', 'Omit dependencies that are shipped with the specified version of perl' ],
}

sub prereqs {
  my ($self, $zilla) = @_;

  $_->before_build for @{ $zilla->plugins_with(-BeforeBuild) };
  $_->gather_files for @{ $zilla->plugins_with(-FileGatherer) };
  $_->set_file_encodings for @{ $zilla->plugins_with(-EncodingProvider) };
  $_->prune_files  for @{ $zilla->plugins_with(-FilePruner) };
  $_->munge_files  for @{ $zilla->plugins_with(-FileMunger) };
  $_->register_prereqs for @{ $zilla->plugins_with(-PrereqSource) };

  my $prereqs = $zilla->prereqs;
}

my @phases = qw/configure build test runtime develop/;
my @relationships = qw/requires recommends suggests/;

sub filter_core {
  my ($prereqs, $core_version) = @_;
  $core_version = sprintf '%7.6f', $core_version if $core_version >= 5.010;
  $prereqs = $prereqs->clone if $prereqs->is_finalized;
  require Module::CoreList;
  for my $phase (@phases) {
    for my $relation (@relationships) {
      my $req = $prereqs->requirements_for($phase, $relation);
      for my $module ($req->required_modules) {
        next if not exists $Module::CoreList::version{$core_version}{$module};
        $req->clear_requirement($module) if $req->accepts_module($module, $Module::CoreList::version{$core_version}{$module});
      }
    }
  }
  return $prereqs;
}

sub extract_dependencies {
  my ($self, $zilla, $phases, $missing, $omit_core) = @_;

  my $prereqs = $self->prereqs($zilla);
  $prereqs = filter_core($prereqs, $omit_core) if $omit_core;

  require CPAN::Meta::Requirements;
  my $req = CPAN::Meta::Requirements->new;

  for my $phase (@$phases) {
    $req->add_requirements( $prereqs->requirements_for($phase, 'requires') );
    $req->add_requirements( $prereqs->requirements_for($phase, 'recommends') );
  }

  require Class::Load;

  my @required = grep { $_ ne 'perl' } $req->required_modules;
  if ($missing) {
    my $is_required = sub {
      my $mod = shift;
      # it is required if it's not already installed
      return 1 unless Class::Load::try_load_class($mod);

      # guard against libs with -1 in $VERSION and other insanity
      my $version;
      return unless try { $version = $mod->VERSION; 1; };

      return !$req->accepts_module($mod => $version);
    };
    @required = grep { $is_required->($_) } @required;
  }

  my $versions = $req->as_string_hash;
  return map { $_ => $versions->{$_} } @required;
}

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

  $self->app->chrome->logger->mute;

  my @phases = qw(build test configure runtime);
  push @phases, 'develop' if $opt->author;

  my $omit_core = $opt->omit_core;
  if($opt->json) {
    my $prereqs = $self->prereqs($self->zilla);
    $prereqs = filter_core($prereqs, $omit_core) if $omit_core;
    my $output = $prereqs->as_string_hash;

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

  my %modules = $self->extract_dependencies($self->zilla, \@phases, $opt->missing, $opt->omit_core);

  if($opt->versions) {
    for(sort { lc $a cmp lc $b } keys %modules) {
      print "$_ = ".$modules{$_}."\n";
    }
  } else {
      print "$_\n" for sort { lc $a cmp lc $b } keys(%modules);
  }
}

1;

__END__

=pod

=encoding UTF-8

=head1 NAME

Dist::Zilla::App::Command::listdeps - print your distribution's prerequisites

=head1 VERSION

version 5.035

=head1 SYNOPSIS

  $ dzil listdeps | cpan

=head1 DESCRIPTION

This is a command plugin for L<Dist::Zilla>. It provides the C<listdeps>
command, which prints your distribution's prerequisites. You could pipe that
list to a CPAN client like L<cpan> to install all of the dependencies in one
quick go.

=head1 OPTIONS

=head2 --author

Include author dependencies (those listed under C<develop_requires>).

=head2 --missing

List only dependencies which are unsatisfied.

=head2 --versions

Also display the required versions of listed modules.

=head2 --json

Lists all prerequisites in JSON format, as they would appear in META.json
(broken out into phases and types)

=head1 ACKNOWLEDGEMENTS

This code was originally more or less a direct copy of Marcel Gruenauer (hanekomu)
Dist::Zilla::App::Command::prereqs, updated to work with the Dist::Zilla v2
API.

=head1 AUTHOR

Ricardo SIGNES <rjbs@cpan.org>

=head1 COPYRIGHT AND LICENSE

This software is copyright (c) 2015 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