#!/usr/bin/perl

use v5.20;

use strict;
use warnings;
use PPI;
use PPI::Dumper;
use Mojo::File qw(path);

die 'Need file' if !$ARGV[0];

my $code = path( $ARGV[0] )->slurp;
my $doc  = PPI::Document->new( \$code );
#PPI::Dumper->new( $doc )->print and exit;

my $top_level_requires = $doc->find(
    sub { 
        $_[1]->isa('PPI::Token::Word') 
        and ( $_[1]->content eq 'requires' or $_[1]->content eq 'recommends' )
        and $_[1]->parent->parent->isa('PPI::Document') }
);

my $feature_requires;
if ( $ARGV[1] ) {
    my $feature_block = $doc->find(
        sub { 
            $_[1]->isa('PPI::Token::Word') and $_[1]->content eq 'feature'
            and
            do {
                my $sibling = $_[1]->snext_sibling; 
                my $value   = $sibling->can('string') ? $sibling->string : $sibling->content;
                $value eq $ARGV[1]
            }
        }
    );

    if ( $feature_block ) {
        $feature_requires = $feature_block->[0]->parent->find(
            sub {
                $_[1]->isa('PPI::Token::Word') and ( $_[1]->content eq 'requires' or $_[1]->content eq 'recommends' )
            }
        );
    }
}

for my $required ( @{ $top_level_requires || [] }, @{ $feature_requires || [] } ) {
    say $required->parent->content;
}