Twice the power of Rot 13.

Rot26.pm

=head1 NAME

Crypt::Rot26 - Encrypt data with TWICE the power of Rot13!!

=head1 SYNOPSIS

  use strict;

  use Crypt::Rot26;

  my $crypt   = Crypt::Rot26->new();
  my $bonham  = 'whole lotta luv!';
  my $crypted = $crypt->crypt($bonham);

  print $crypted, "\n";
  print $crypt->decrypt($crypted), "\n";

=cut

package Crypt::Rot26;

sub new {
   my ($proto) = @_;
   my $class   = ref $proto || $proto;
   my $self    = {
      rot    => 26,
      offset => { map { $_ => 97, uc $_ => 65 } ('a'..'z') },
   };

   bless $self, $class;
   return $self;
}

sub crypt   { do_it(@_,'+'); }
sub decrypt { do_it(@_,'-'); }

sub do_it {
   my ($self,$str,$op) = @_;
   my $crypted  = '';
   my $rotation = $self->{rot};

   foreach my $chr (split('',$str)) {
      if ($chr =~ /[A-Za-z]/) {
         my $offset = $self->{offset}->{$chr};
         my $shift  = eval "$offset $op $rotation";
         $chr = chr((ord($chr) - $shift) % 26 + $offset);
      }
      $crypted .= $chr;
   }

   return $crypted;
}

1;