package Filter::ObfuMethods;

use Exporter::Tidy
  default => [ 'filter' ];

use Crypt::Rot13;

use vars '%methods';

sub filter {
  my $code = pop;

  my(@calls) = $code =~ m{ \$? \w+ \s* -> \s* (\w+) }gx;

  @methods{map crypt_method($_), @calls} = @calls;

  $code =~ s{ ( \$? \w+ \s* -> \s* ) $methods{$_} }
            ($1\${\\\$Filter::ObfuMethods::methods{"$_"}})gx
    for keys %methods;

  return $code;
}

sub crypt_method {
  my $c = Crypt::Rot13->new;
  $c->charge(shift);
  return $c->rot13(6);

}

q[the end];

##</code><code>##

use Filter::ObfuMethods;

my $code = <<'CODE';
sub foo { print "in foo\n" }
sub bar { print "in bar\n" }

main->foo;
main -> bar();

my $o = bless [];

$o->foo();
$o -> bar;
CODE

print filter($code);

eval filter($code);

warn "ack - $@" if $@;

__output__

sub foo { print "in foo\n" }
sub bar { print "in bar\n" }

main->${\$Filter::ObfuMethods::methods{"luu"}};
main -> ${\$Filter::ObfuMethods::methods{"hgx"}}();

my $o = bless [];

$o->${\$Filter::ObfuMethods::methods{"luu"}}();
$o -> ${\$Filter::ObfuMethods::methods{"hgx"}};
in foo
in bar
in foo
in bar