Enigma Javascript

gistfile1.js

;'use strict';

enigma = (function() {

	var _rotors = [	'EKMFLGDQVZNTOWYHXUSPAIBRCJ',
					'AJDKSIRUXBLHWTMCQGZNPYFVOE',
					'BDFHJLCPRTXVZNYEIWGAKMUSQO'
		]
	,	_reflector = "YRUHQSLDPXNGOKMIEBFZCWVJAT"
	,	_alpha = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
	,	_key = "ABC";

	return {
	    crypt: function(ct) {
			// Sets initial permutation
			var L = li(_key[0])
			,	M = li(_key[1])
			,	R = li(_key[2])
			,	output = '';

			for (x = 0; x < ct.length; x++) {
				ct_letter = li(ct[x]);

				// Step right rotor on every iteration
				R = mod26(R + 1);

				// Pass through rotors
				a = _rotors[2][mod26(R + ct_letter)];
				b = _rotors[1][mod26(M + li(a) - R)];
				c = _rotors[0][mod26(L + li(b) - M)];

				// Pass through reflector
				ref = _reflector[mod26(li(c) - L)];

				// Inverse rotor pass
				d = mod26(_rotors[0].indexOf(_alpha[mod26(li(ref) + L)]) - L);
				e = mod26(_rotors[1].indexOf(_alpha[mod26(d + M)]) - M);
				f = _alpha[mod26(_rotors[2].indexOf(_alpha[mod26(e + R)]) - R)];

				output += f;
			}

			return output;
	  	}
	}

})();

function li(l) {
	// Letter to index
	return "ABCDEFGHIJKLMNOPQRSTUVWXYZ".indexOf(l);
}

function mod26(n) {
	// Takes into account negative modulo
	return ((n % 26) + 26) % 26;
}


var start = new Date().getTime();

var i = 1000000;

// do {

    enigma.crypt('PZUFWDSASJGQGNRMAEODZJXQQKHSYGVUSGSU');

// } while (i--);