package ExtUtils::MM;

use strict;
use ExtUtils::MakeMaker::Config;

our $VERSION = '6.66';

require ExtUtils::Liblist;
require ExtUtils::MakeMaker;
our @ISA = qw(ExtUtils::Liblist ExtUtils::MakeMaker);

=head1 NAME

ExtUtils::MM - OS adjusted ExtUtils::MakeMaker subclass

=head1 SYNOPSIS

require ExtUtils::MM;
my $mm = MM->new(...);

=head1 DESCRIPTION

B<FOR INTERNAL USE ONLY>

ExtUtils::MM is a subclass of ExtUtils::MakeMaker which automatically
chooses the appropriate OS specific subclass for you
(ie. ExtUils::MM_Unix, etc...).

It also provides a convenient alias via the MM class (I didn't want
MakeMaker modules outside of ExtUtils/).

This class might turn out to be a temporary solution, but MM won't go
away.

=cut

{
# Convenient alias.
package MM;
our @ISA = qw(ExtUtils::MM);
sub DESTROY {}
}

sub _is_win95 {
# miniperl might not have the Win32 functions available and we need
# to run in miniperl.
my $have_win32 = eval { require Win32 };
return $have_win32 && defined &Win32::IsWin95 ? Win32::IsWin95()
: ! defined $ENV{SYSTEMROOT};
}

my %Is = ();
$Is{VMS} = $^O eq 'VMS';
$Is{OS2} = $^O eq 'os2';
$Is{MacOS} = $^O eq 'MacOS';
if( $^O eq 'MSWin32' ) {
_is_win95() ? $Is{Win95} = 1 : $Is{Win32} = 1;
}
$Is{UWIN} = $^O =~ /^uwin(-nt)?$/;
$Is{Cygwin} = $^O eq 'cygwin';
$Is{NW5} = $Config{osname} eq 'NetWare'; # intentional
$Is{BeOS} = ($^O =~ /beos/i or $^O eq 'haiku');
$Is{DOS} = $^O eq 'dos';
if( $Is{NW5} ) {
$^O = 'NetWare';
delete $Is{Win32};
}
$Is{VOS} = $^O eq 'vos';
$Is{QNX} = $^O eq 'qnx';
$Is{AIX} = $^O eq 'aix';
$Is{Darwin} = $^O eq 'darwin';

$Is{Unix} = !grep { $_ } values %Is;

map { delete $Is{$_} unless $Is{$_} } keys %Is;
_assert( keys %Is == 1 );
my($OS) = keys %Is;


my $class = "ExtUtils::MM_$OS";
eval "require $class" unless $INC{"ExtUtils/MM_$OS.pm"}; ## no critic
die $@ if $@;
unshift @ISA, $class;


sub _assert {
my $sanity = shift;
die sprintf "Assert failed at %s line %d\n", (caller)[1,2] unless $sanity;
return;
}