From 53cc413eaee00d1de585abfafbdc5cec5ae2413c Mon Sep 17 00:00:00 2001
From: s2224834 <46319860+s2224834@users.noreply.github.com>
Date: Thu, 3 Jan 2019 18:48:50 +0000
Subject: [PATCH] Typex: move machine implementation to lib/

---
 src/core/lib/Typex.mjs        | 183 ++++++++++++++++++++++++++++++++
 src/core/operations/Typex.mjs | 193 ++--------------------------------
 2 files changed, 193 insertions(+), 183 deletions(-)
 create mode 100644 src/core/lib/Typex.mjs

diff --git a/src/core/lib/Typex.mjs b/src/core/lib/Typex.mjs
new file mode 100644
index 00000000..a99f3b6e
--- /dev/null
+++ b/src/core/lib/Typex.mjs
@@ -0,0 +1,183 @@
+/**
+ * Emulation of the Typex machine.
+ *
+ * @author s2224834
+ * @copyright Crown Copyright 2019
+ * @license Apache-2.0
+ */
+import OperationError from "../errors/OperationError";
+import * as Enigma from "../lib/Enigma";
+import Utils from "../Utils";
+
+export const ROTORS = [
+    {name: "1", value: "QWECYJIBFKMLTVZPOHUDGNRSXA<ACEINQTVY"},
+    {name: "2", value: "AJDKSIRUXBLHWTMCQGZNPYFVOE<ACEINQTVY"},
+    {name: "3", value: "BDFHJLCPRTXVZNYEIWGAKMUSQO<ACEINQTVY"},
+    {name: "4", value: "ESOVPZJAYQUIRHXLNFTGKDCMWB<ACEINQTVY"},
+    {name: "5", value: "VZBRGITYUPSDNHLXAWMJQOFECK<ACEINQTVY"},
+    {name: "6", value: "FVPJIAOYEDRZXWGCTKUQSBNMHL<ACEINQTVY"},
+    {name: "7", value: "KZGLIUCJEHADXRYWVTNSFQPMOB<ACEINQTVY"},
+    {name: "8", value: "ZLVGOIFTYWUEPMABNCXRQSDKHJ<ACEINQTVY"},
+];
+
+export const REFLECTORS = [
+    {name: "Standard", value: "MO VW GL JX TZ AY EQ IP KN DH CU FS BR"},
+];
+
+// Special character handling on Typex keyboard
+const KEYBOARD = {
+    "Q": "1", "W": "2", "E": "3", "R": "4", "T": "5", "Y": "6", "U": "7", "I": "8", "O": "9", "P": "0",
+    "A": "-", "S": "/", "D": "Z", "F": "%", "G": "X", "H": "£", "K": "(", "L": ")",
+    "C": "V", "B": "'", "N": ",", "M": "."
+};
+const KEYBOARD_REV = {};
+for (const i of Object.keys(KEYBOARD)) {
+    KEYBOARD_REV[KEYBOARD[i]] = i;
+}
+
+/**
+ * Typex machine. A lot like the Enigma, but five rotors, of which the first two are static.
+ */
+export class TypexMachine extends Enigma.EnigmaBase {
+    /**
+     * TypexMachine constructor.
+     *
+     * @param {Object[]} rotors - List of Rotors.
+     * @param {Object} reflector - A Reflector.
+     * @param {Plugboard} plugboard - A Plugboard.
+     */
+    constructor(rotors, reflector, plugboard, keyboard) {
+        super(rotors, reflector, plugboard);
+        if (rotors.length !== 5) {
+            throw new OperationError("Typex must have 5 rotors");
+        }
+        this.keyboard = keyboard;
+    }
+
+    /**
+     * This is the same as the Enigma step function, it's just that the right-
+     * most two rotors are static.
+     */
+    step() {
+        const r0 = this.rotors[2];
+        const r1 = this.rotors[3];
+        r0.step();
+        // The second test here is the double-stepping anomaly
+        if (r0.steps.has(r0.pos) || r1.steps.has(Utils.mod(r1.pos + 1, 26))) {
+            r1.step();
+            if (r1.steps.has(r1.pos)) {
+                const r2 = this.rotors[4];
+                r2.step();
+            }
+        }
+    }
+
+    /**
+     * Encrypt/decrypt data. This is identical to the Enigma version cryptographically, but we have
+     * additional handling for the Typex's keyboard (which handles various special characters by
+     * mapping them to particular letter combinations).
+     *
+     * @param {string} input - The data to encrypt/decrypt.
+     * @return {string}
+     */
+    crypt(input) {
+        let inputMod = input;
+        if (this.keyboard === "Encrypt") {
+            inputMod = "";
+            // true = in symbol mode
+            let mode = false;
+            for (const x of input) {
+                if (x === " ") {
+                    inputMod += "X";
+                } else if (mode) {
+                    if (KEYBOARD_REV.hasOwnProperty(x)) {
+                        inputMod += KEYBOARD_REV[x];
+                    } else {
+                        mode = false;
+                        inputMod += "V" + x;
+                    }
+                } else {
+                    if (KEYBOARD_REV.hasOwnProperty(x)) {
+                        mode = true;
+                        inputMod += "Z" + KEYBOARD_REV[x];
+                    } else {
+                        inputMod += x;
+                    }
+                }
+            }
+        }
+
+        const output = super.crypt(inputMod);
+
+        let outputMod = output;
+        if (this.keyboard === "Decrypt") {
+            outputMod = "";
+            let mode = false;
+            for (const x of output) {
+                if (x === "X") {
+                    outputMod += " ";
+                } else if (x === "V") {
+                    mode = false;
+                } else if (x === "Z") {
+                    mode = true;
+                } else if (mode) {
+                    outputMod += KEYBOARD[x];
+                } else {
+                    outputMod += x;
+                }
+            }
+        }
+        return outputMod;
+    }
+}
+
+/**
+ * Typex rotor. Like an Enigma rotor, but no ring setting, and can be reversed.
+ */
+export class Rotor extends Enigma.Rotor {
+    /**
+     * Rotor constructor.
+     *
+     * @param {string} wiring - A 26 character string of the wiring order.
+     * @param {string} steps - A 0..26 character string of stepping points.
+     * @param {bool} reversed - Whether to reverse the rotor.
+     * @param {char} initialPosition - The initial position of the rotor.
+     */
+    constructor(wiring, steps, reversed, initialPos) {
+        let initialPosMod = initialPos;
+        let wiringMod = wiring;
+        if (reversed) {
+            initialPosMod = Enigma.i2a(Utils.mod(26 - Enigma.a2i(initialPos), 26));
+            const outMap = new Array(26).fill();
+            for (let i=0; i<26; i++) {
+                // wiring[i] is the original output
+                // Enigma.LETTERS[i] is the original input
+                const input = Utils.mod(26 - Enigma.a2i(wiring[i]), 26);
+                const output = Enigma.i2a(Utils.mod(26 - Enigma.a2i(Enigma.LETTERS[i]), 26));
+                outMap[input] = output;
+            }
+            wiringMod = outMap.join("");
+        }
+        super(wiringMod, steps, "A", initialPosMod);
+    }
+}
+
+/**
+ * Typex input plugboard. Based on a Rotor, because it allows arbitrary maps, not just switches
+ * like the Enigma plugboard.
+ * Not to be confused with the reflector plugboard.
+ */
+export class Plugboard extends Enigma.Rotor {
+    /**
+     * Typex plugboard constructor.
+     *
+     * @param {string} wiring - 26 character string of mappings from A-Z, as per rotors, or "".
+     */
+    constructor(wiring) {
+        try {
+            super(wiring, "", "A", "A");
+        } catch (err) {
+            throw new OperationError(err.message.replace("Rotor", "Plugboard"));
+        }
+    }
+}
diff --git a/src/core/operations/Typex.mjs b/src/core/operations/Typex.mjs
index 89114863..a84daf09 100644
--- a/src/core/operations/Typex.mjs
+++ b/src/core/operations/Typex.mjs
@@ -8,186 +8,13 @@
 
 import Operation from "../Operation";
 import OperationError from "../errors/OperationError";
-import Utils from "../Utils";
-import * as Enigma from "../lib/Enigma";
-
-const ROTORS = [
-    {name: "1", value: "QWECYJIBFKMLTVZPOHUDGNRSXA<ACEINQTVY"},
-    {name: "2", value: "AJDKSIRUXBLHWTMCQGZNPYFVOE<ACEINQTVY"},
-    {name: "3", value: "BDFHJLCPRTXVZNYEIWGAKMUSQO<ACEINQTVY"},
-    {name: "4", value: "ESOVPZJAYQUIRHXLNFTGKDCMWB<ACEINQTVY"},
-    {name: "5", value: "VZBRGITYUPSDNHLXAWMJQOFECK<ACEINQTVY"},
-    {name: "6", value: "FVPJIAOYEDRZXWGCTKUQSBNMHL<ACEINQTVY"},
-    {name: "7", value: "KZGLIUCJEHADXRYWVTNSFQPMOB<ACEINQTVY"},
-    {name: "8", value: "ZLVGOIFTYWUEPMABNCXRQSDKHJ<ACEINQTVY"},
-];
-
-const REFLECTORS = [
-    {name: "Standard", value: "MO VW GL JX TZ AY EQ IP KN DH CU FS BR"},
-];
-
-// Special character handling on Typex keyboard
-const KEYBOARD = {
-    "Q": "1", "W": "2", "E": "3", "R": "4", "T": "5", "Y": "6", "U": "7", "I": "8", "O": "9", "P": "0",
-    "A": "-", "S": "/", "D": "Z", "F": "%", "G": "X", "H": "£", "K": "(", "L": ")",
-    "C": "V", "B": "'", "N": ",", "M": "."
-};
-const KEYBOARD_REV = {};
-for (const i of Object.keys(KEYBOARD)) {
-    KEYBOARD_REV[KEYBOARD[i]] = i;
-}
-
-/**
- * Typex machine. A lot like the Enigma, but five rotors, of which the first two are static.
- */
-class TypexMachine extends Enigma.EnigmaBase {
-    /**
-     * TypexMachine constructor.
-     *
-     * @param {Object[]} rotors - List of Rotors.
-     * @param {Object} reflector - A Reflector.
-     * @param {Plugboard} plugboard - A Plugboard.
-     */
-    constructor(rotors, reflector, plugboard, keyboard) {
-        super(rotors, reflector, plugboard);
-        if (rotors.length !== 5) {
-            throw new OperationError("Typex must have 5 rotors");
-        }
-        this.keyboard = keyboard;
-    }
-
-    /**
-     * This is the same as the Enigma step function, it's just that the right-
-     * most two rotors are static.
-     */
-    step() {
-        const r0 = this.rotors[2];
-        const r1 = this.rotors[3];
-        r0.step();
-        // The second test here is the double-stepping anomaly
-        if (r0.steps.has(r0.pos) || r1.steps.has(Utils.mod(r1.pos + 1, 26))) {
-            r1.step();
-            if (r1.steps.has(r1.pos)) {
-                const r2 = this.rotors[4];
-                r2.step();
-            }
-        }
-    }
-
-    /**
-     * Encrypt/decrypt data. This is identical to the Enigma version cryptographically, but we have
-     * additional handling for the Typex's keyboard (which handles various special characters by
-     * mapping them to particular letter combinations).
-     *
-     * @param {string} input - The data to encrypt/decrypt.
-     * @return {string}
-     */
-    crypt(input) {
-        let inputMod = input;
-        if (this.keyboard === "Encrypt") {
-            inputMod = "";
-            // true = in symbol mode
-            let mode = false;
-            for (const x of input) {
-                if (x === " ") {
-                    inputMod += "X";
-                } else if (mode) {
-                    if (KEYBOARD_REV.hasOwnProperty(x)) {
-                        inputMod += KEYBOARD_REV[x];
-                    } else {
-                        mode = false;
-                        inputMod += "V" + x;
-                    }
-                } else {
-                    if (KEYBOARD_REV.hasOwnProperty(x)) {
-                        mode = true;
-                        inputMod += "Z" + KEYBOARD_REV[x];
-                    } else {
-                        inputMod += x;
-                    }
-                }
-            }
-        }
-
-        const output = super.crypt(inputMod);
-
-        let outputMod = output;
-        if (this.keyboard === "Decrypt") {
-            outputMod = "";
-            let mode = false;
-            for (const x of output) {
-                if (x === "X") {
-                    outputMod += " ";
-                } else if (x === "V") {
-                    mode = false;
-                } else if (x === "Z") {
-                    mode = true;
-                } else if (mode) {
-                    outputMod += KEYBOARD[x];
-                } else {
-                    outputMod += x;
-                }
-            }
-        }
-        return outputMod;
-    }
-}
-
-/**
- * Typex rotor. Like an Enigma rotor, but no ring setting, and can be reversed.
- */
-class Rotor extends Enigma.Rotor {
-    /**
-     * Rotor constructor.
-     *
-     * @param {string} wiring - A 26 character string of the wiring order.
-     * @param {string} steps - A 0..26 character string of stepping points.
-     * @param {bool} reversed - Whether to reverse the rotor.
-     * @param {char} initialPosition - The initial position of the rotor.
-     */
-    constructor(wiring, steps, reversed, initialPos) {
-        let initialPosMod = initialPos;
-        let wiringMod = wiring;
-        if (reversed) {
-            initialPosMod = Enigma.i2a(Utils.mod(26 - Enigma.a2i(initialPos), 26));
-            const outMap = new Array(26).fill();
-            for (let i=0; i<26; i++) {
-                // wiring[i] is the original output
-                // Enigma.LETTERS[i] is the original input
-                const input = Utils.mod(26 - Enigma.a2i(wiring[i]), 26);
-                const output = Enigma.i2a(Utils.mod(26 - Enigma.a2i(Enigma.LETTERS[i]), 26));
-                outMap[input] = output;
-            }
-            wiringMod = outMap.join("");
-        }
-        super(wiringMod, steps, "A", initialPosMod);
-    }
-}
-
-/**
- * Typex input plugboard. Based on a Rotor, because it allows arbitrary maps, not just switches
- * like the Enigma plugboard.
- * Not to be confused with the reflector plugboard.
- */
-class Plugboard extends Enigma.Rotor {
-    /**
-     * Typex plugboard constructor.
-     *
-     * @param {string} wiring - 26 character string of mappings from A-Z, as per rotors, or "".
-     */
-    constructor(wiring) {
-        try {
-            super(wiring, "", "A", "A");
-        } catch (err) {
-            throw new OperationError(err.message.replace("Rotor", "Plugboard"));
-        }
-    }
-}
+import {LETTERS, Reflector} from "../lib/Enigma";
+import {ROTORS, REFLECTORS, TypexMachine, Plugboard, Rotor} from "../lib/Typex";
 
 /**
  * Typex operation
  */
-class TypexOp extends Operation {
+class Typex extends Operation {
     /**
      * Typex constructor
      */
@@ -215,7 +42,7 @@ class TypexOp extends Operation {
             {
                 name: "1st rotor initial value",
                 type: "option",
-                value: Enigma.LETTERS
+                value: LETTERS
             },
             {
                 name: "2nd (static) rotor",
@@ -231,7 +58,7 @@ class TypexOp extends Operation {
             {
                 name: "2nd rotor initial value",
                 type: "option",
-                value: Enigma.LETTERS
+                value: LETTERS
             },
             {
                 name: "3rd rotor",
@@ -247,7 +74,7 @@ class TypexOp extends Operation {
             {
                 name: "3rd rotor initial value",
                 type: "option",
-                value: Enigma.LETTERS
+                value: LETTERS
             },
             {
                 name: "4th rotor",
@@ -263,7 +90,7 @@ class TypexOp extends Operation {
             {
                 name: "4th rotor initial value",
                 type: "option",
-                value: Enigma.LETTERS
+                value: LETTERS
             },
             {
                 name: "5th rotor",
@@ -279,7 +106,7 @@ class TypexOp extends Operation {
             {
                 name: "5th rotor initial value",
                 type: "option",
-                value: Enigma.LETTERS
+                value: LETTERS
             },
             {
                 name: "Reflector",
@@ -338,7 +165,7 @@ class TypexOp extends Operation {
             const [rotorwiring, rotorsteps] = this.parseRotorStr(args[i*3]);
             rotors.push(new Rotor(rotorwiring, rotorsteps, args[i*3 + 1], args[i*3+2]));
         }
-        const reflector = new Enigma.Reflector(reflectorstr);
+        const reflector = new Reflector(reflectorstr);
         let plugboardstrMod = plugboardstr;
         if (plugboardstrMod === "") {
             plugboardstrMod = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
@@ -393,4 +220,4 @@ class TypexOp extends Operation {
 
 }
 
-export default TypexOp;
+export default Typex;