Implemented offset and added tests

src/core/operations/RailFenceCipherDecode.mjs

@@ -7,19 +7,19 @@
 import Operation from "../Operation.mjs";
 
 /**
- * Rail Fence Cypher Decode operation
+ * Rail Fence Cipher Decode operation
  */
-class RailFenceCypherDecode extends Operation {
+class RailFenceCipherDecode extends Operation {
 
     /**
-     * RailFenceCypherDecode constructor
+     * RailFenceCipherDecode constructor
      */
     constructor() {
         super();
 
-        this.name = "Rail Fence Cypher Decode";
+        this.name = "Rail Fence Cipher Decode";
         this.module = "Ciphers";
-        this.description = "Decodes Strings that were created using the Rail fence Cypher provided a key and an offset";
+        this.description = "Decodes Strings that were created using the Rail fence Cipher provided a key and an offset";
         this.infoURL = "https://en.wikipedia.org/wiki/Rail_fence_cipher";
         this.inputType = "string";
         this.outputType = "string";
@@ -43,8 +43,7 @@ class RailFenceCypherDecode extends Operation {
      * @returns {string}
      */
     run(input, args) {
-        const [key] = args;
+        const [key, offset] = args;
-        // const [key, offset] = args;
 
         let cipher = input;
 
@@ -54,51 +53,35 @@ class RailFenceCypherDecode extends Operation {
             return "Key should be smaller than the cipher's length";
         }
 
+        if (offset < 0) {
+            return "Offset has to be a positive integer";
+        }
+
+        const cycle = (key - 1) * 2;
+
         const rest = cipher.length % key;
 
         if (rest !== 0) {
             cipher = cipher + (" ".repeat(key - rest));
         }
 
-        const blockLen = cipher.length / key;
+        const plaintext = new Array(cipher.length);
 
-        let plaintext = "";
+        let j = 0;
+        let x, y;
 
-        for (let i = 0; i < blockLen; i++) {
+        for (y = 0; y < key; y++) {
-            for (let j = 0; j < key; j++) {
+            for (x = 0; x < cipher.length; x++) {
-                plaintext += cipher[i + (j * blockLen)];
+                if ((y + x + offset) % cycle === 0 || (y - x - offset) % cycle === 0) {
+                    plaintext[x] = cipher[j++];
+                }
             }
         }
 
-        return plaintext;
+        return plaintext.join("").trim();
     }
 
-    /**
-     * Highlight Rail Fence Cypher Decode
-     *
-     * @param {Object[]} pos
-     * @param {number} pos[].start
-     * @param {number} pos[].end
-     * @param {Object[]} args
-     * @returns {Object[]} pos
-     */
-    highlight(pos, args) {
-        return pos;
-    }
-
-    /**
-     * Highlight Rail Fence Cypher Decode in reverse
-     *
-     * @param {Object[]} pos
-     * @param {number} pos[].start
-     * @param {number} pos[].end
-     * @param {Object[]} args
-     * @returns {Object[]} pos
-     */
-    highlightReverse(pos, args) {
-        return pos;
-    }
 }
 
 
-export default RailFenceCypherDecode;
+export default RailFenceCipherDecode;

src/core/operations/RailFenceCipherEncode.mjs

@@ -7,19 +7,19 @@
 import Operation from "../Operation.mjs";
 
 /**
- * Rail Fence Cypher Encode operation
+ * Rail Fence Cipher Encode operation
  */
-class RailFenceCypherEncode extends Operation {
+class RailFenceCipherEncode extends Operation {
 
     /**
-     * RailFenceCypherEncode constructor
+     * RailFenceCipherEncode constructor
      */
     constructor() {
         super();
 
-        this.name = "Rail Fence Cypher Encode";
+        this.name = "Rail Fence Cipher Encode";
         this.module = "Ciphers";
-        this.description = "Encodes Strings using the Rail fence Cypher provided a key and an offset";
+        this.description = "Encodes Strings using the Rail fence Cipher provided a key and an offset";
         this.infoURL = "https://en.wikipedia.org/wiki/Rail_fence_cipher";
         this.inputType = "string";
         this.outputType = "string";
@@ -43,54 +43,31 @@ class RailFenceCypherEncode extends Operation {
      * @returns {string}
      */
     run(input, args) {
-        const [key] = args;
+        const [key, offset] = args;
-        // const [key, offset] = args;
 
         const plaintext = input;
-
         if (key < 2) {
             return "Key has to be bigger than 2";
         } else if (key > plaintext.length) {
             return "Key should be smaller than the plain text's length";
         }
 
-        let cipher = "";
+        if (offset < 0) {
-
+            return "Offset has to be a positive integer";
-        for (let block = 0; block < key; block++) {
-            for (let pos = block; pos < plaintext.length; pos += key) {
-                cipher += plaintext[pos];
-            }
         }
 
-        return cipher;
+        const cycle = (key - 1) * 2;
+        const rows = new Array(key).fill("");
+
+        for (let pos = 0; pos < plaintext.length; pos++) {
+            const rowIdx = key - 1 - Math.abs(cycle / 2 - (pos + offset) % cycle);
+
+            rows[rowIdx] += plaintext[pos];
         }
 
-    /**
+        return rows.join("").trim();
-     * Highlight Rail Fence Cypher Encode
-     *
-     * @param {Object[]} pos
-     * @param {number} pos[].start
-     * @param {number} pos[].end
-     * @param {Object[]} args
-     * @returns {Object[]} pos
-     */
-    highlight(pos, args) {
-        return pos;
-    }
-
-    /**
-     * Highlight Rail Fence Cypher Encode in reverse
-     *
-     * @param {Object[]} pos
-     * @param {number} pos[].start
-     * @param {number} pos[].end
-     * @param {Object[]} args
-     * @returns {Object[]} pos
-     */
-    highlightReverse(pos, args) {
-        return pos;
     }
 
 }
 
-export default RailFenceCypherEncode;
+export default RailFenceCipherEncode;

tests/operations/tests/Ciphers.mjs

@@ -420,36 +420,113 @@ TestRegister.addTests([
         ],
     },
     {
-        name: "Rail Fence Cypher Decode: normal",
+        name: "Rail Fence Cipher Decode: normal",
         input: "Cytgah sTEAto rtn rsligcdsrporpyi H r fWiigo ovn oe",
         expectedOutput: "Cryptography is THE Art of Writing or solving codes",
         recipeConfig: [
             {
-                "op": "Rail Fence Cypher Decode",
+                "op": "Rail Fence Cipher Decode",
                 "args": [2, 0]
             }
         ],
     },
     {
-        name: "Rail Fence Cypher Decode: key has to be bigger than 2",
+        name: "Rail Fence Cipher Decode: key has to be bigger than 2",
         input: "Cytgah sTEAto rtn rsligcdsrporpyi H r fWiigo ovn oe",
         expectedOutput: "Key has to be bigger than 2",
         recipeConfig: [
             {
-                "op": "Rail Fence Cypher Decode",
+                "op": "Rail Fence Cipher Decode",
                 "args": [1, 0]
             }
         ],
     },
     {
-        name: "Rail Fence Cypher Decode: key has to be smaller than input's length",
+        name: "Rail Fence Cipher Decode: key has to be smaller than input's length",
         input: "shortinput",
         expectedOutput: "Key should be smaller than the cipher's length",
         recipeConfig: [
             {
-                "op": "Rail Fence Cypher Decode",
+                "op": "Rail Fence Cipher Decode",
                 "args": [22, 0]
             }
         ],
     },
+    {
+        name: "Rail Fence Cipher Decode: offset should be positive",
+        input: "shortinput",
+        expectedOutput: "Offset has to be a positive integer",
+        recipeConfig: [
+            {
+                "op": "Rail Fence Cipher Decode",
+                "args": [2, -1]
+            }
+        ],
+    },
+    {
+        name: "Rail Fence Cipher Decode: Normal with Offset non-null",
+        input: "51746026813793592840",
+        expectedOutput: "12345678901234567890",
+        recipeConfig: [
+            {
+                "op": "Rail Fence Cipher Decode",
+                "args": [4, 2]
+            }
+        ],
+    },
+    {
+        name: "Rail Fence Cipher Encode: normal",
+        input: "Cryptography is THE Art of Writing or solving codes",
+        expectedOutput: "Cytgah sTEAto rtn rsligcdsrporpyi H r fWiigo ovn oe",
+        recipeConfig: [
+            {
+                "op": "Rail Fence Cipher Encode",
+                "args": [2, 0]
+            }
+        ],
+    },
+    {
+        name: "Rail Fence Cipher Encode: key has to be bigger than 2",
+        input: "Cryptography is THE Art of Writing or solving codes",
+        expectedOutput: "Key has to be bigger than 2",
+        recipeConfig: [
+            {
+                "op": "Rail Fence Cipher Encode",
+                "args": [1, 0]
+            }
+        ],
+    },
+    {
+        name: "Rail Fence Cipher Encode: key has to be smaller than input's length",
+        input: "shortinput",
+        expectedOutput: "Key should be smaller than the plain text's length",
+        recipeConfig: [
+            {
+                "op": "Rail Fence Cipher Encode",
+                "args": [22, 0]
+            }
+        ],
+    },
+    {
+        name: "Rail Fence Cipher Encode: offset should be positive",
+        input: "shortinput",
+        expectedOutput: "Offset has to be a positive integer",
+        recipeConfig: [
+            {
+                "op": "Rail Fence Cipher Encode",
+                "args": [2, -1]
+            }
+        ],
+    },
+    {
+        name: "Rail Fence Cipher Encode: Normal with Offset non-null",
+        input: "12345678901234567890",
+        expectedOutput: "51746026813793592840",
+        recipeConfig: [
+            {
+                "op": "Rail Fence Cipher Encode",
+                "args": [4, 2]
+            }
+        ],
+    },
 ]);