#!/usr/bin/perl
use warnings;
use strict;

use Module::CoreList;

# find the highest subversion of perl in a family: e.g. 5.008007 for 5
+.008
sub highest_subversion {
    my ($perl_version, $module) = @_;

    # find the highest perl release for this version of perl
    return [reverse sort @{$Module::CoreList::families{$perl_version}}
+]->[0];
}

# find what version of a module is in a specific version of perl
sub core_version {
    my ($perl_version, $module) = @_;

    if ( exists $Module::CoreList::version{$perl_version}{$module} ) {
        return $Module::CoreList::version{$perl_version}{$module};
    } else {
        return;
    }
}

# print out the history of when a module was included in various perl 
+releases
sub module_history {
    my ($module) = @_;
    
    my $in_core = Module::CoreList->first_release($module);
    
    if ($in_core) {
        print "$module version(s): \n";
        for my $version (qw( 5.004 5.005 5.006 5.008 )) {
            my $subversion = highest_subversion( $version );
            my $core_version = core_version( $subversion, $module);
            $core_version = "unknown version" unless $core_version;
            print "    $core_version in perl $subversion\n";
        }
    }
    else {
        print "$module: never released in core\n"
    }
}

module_history(shift @ARGV);
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