#!/usr/bin/perl

use strict;

my @wheel1 = qw( 8 4 6 6 3 3 8 4 );
my @wheel2 = qw( 1 2 4 6 3 8 8 9 5 1 6 1 7 2 8 1 );
print "KEY:";
chomp(my $key = <STDIN>);
my @wheel3 = map(ord, split //, $key);

my $file = @ARGV[0];
$/ = undef;
print "OPENING $file\n";
open(IN, "$file") || die "painful death! (because there is no $file)";
my ($out);
my $plaintext = <IN>;
close(IN);
open(OUT, ">$file");

my @nums = map(ord, split //, $plaintext);

foreach (@nums) {
print "*";
my $x = @wheel1[0] + @wheel2[0] + @wheel3[0];

if (@ARGV[1] eq "-d") {
$out = $_ + $x;
} else {
$out = $_ - $x;
}
$out = chr $out;

print OUT $out;

push @wheel1, shift @wheel1;
push @wheel2, shift @wheel2;
print "\b";
}