enigma/test/enigma-rotation.js

Implementation of an enigma machine

/*
 * Enigma#rotate()
 */

var test = require('tape');

var enigmajs = require('..');

// Creating the components of the machine

var eintrittswalzen = [];
eintrittswalzen.push( new enigmajs.Eintrittswalze('ABCDEFGHIJKLMNOPQRSTUVWXYZ') );

var rotoren = [];
rotoren.push( new enigmajs.Rotor('EKMFLGDQVZNTOWYHXUSPAIBRCJ', 'Q',  'I') );
rotoren.push( new enigmajs.Rotor('AJDKSIRUXBLHWTMCQGZNPYFVOE', 'E',  'II') );
rotoren.push( new enigmajs.Rotor('BDFHJLCPRTXVZNYEIWGAKMUSQO', 'V',  'III') );
rotoren.push( new enigmajs.Rotor('ESOVPZJAYQUIRHXLNFTGKDCMWB', 'J',  'IV') );
rotoren.push( new enigmajs.Rotor('VZBRGITYUPSDNHLXAWMJQOFECK', 'Z',  'V') );
// rotoren.push( new enigmajs.Rotor('JPGVOUMFYQBENHZRDKASXLICTW', 'ZM', 'VI') );
// rotoren.push( new enigmajs.Rotor('NZJHGRCXMYSWBOUFAIVLPEKQDT', 'ZM', 'VII') );
// rotoren.push( new enigmajs.Rotor('FKQHTLXOCBJSPDZRAMEWNIUYGV', 'ZM', 'VIII') );

var umkehrwalzen = [];
umkehrwalzen.push( new enigmajs.Umkehrwalze('EJMZALYXVBWFCRQUONTSPIKHGD') );
umkehrwalzen.push( new enigmajs.Umkehrwalze('YRUHQSLDPXNGOKMIEBFZCWVJAT') );
umkehrwalzen.push( new enigmajs.Umkehrwalze('FVPJIAOYEDRZXWGCTKUQSBNMHL') );

var steckerbrett = new enigmajs.Steckerbrett('');

var enigma;

var permutations = [];

for (var i = 0; i < rotoren.length; i++) {
  for (var j = 0; j < rotoren.length; j++) {
    for (var k = 0; k < rotoren.length; k++) {
      if ( i !== j && i !== k && j !== k )
        permutations.push([rotoren[i], rotoren[j], rotoren[k]]);
    }
  }
}

test('Enigma#rotate()', function (t) {

  t.plan(1);

  for (var i = 0; i < eintrittswalzen.length; i++) {
    var eintrittswalze = eintrittswalzen[i];

    for (var j = 0; j < umkehrwalzen.length; j++) {
      var ukw = umkehrwalzen[j];

      for (var k = 0; k < permutations.length; k++) {

        enigma = null;
        enigma = new enigmajs.Enigma(permutations[k], ukw, steckerbrett, eintrittswalze);

        enigma.setPositions('AAA');
        enigma.setRingSettings('AAA');

        for (var l = 1; l < (26*25*26+1); l++) {
          enigma.rotate();
        }

      }
    }
  }

  t.equal(enigma.getPositions(), 'AAA', '#getPositions() should return `AAA` after 16901 calls of #rotate()');

});