add oneTimePad algorithm

Author: shams-nahid

.idea/workspace.xml

@@ -1,11 +1,12 @@
 const caesarCipher = (mainString, num, cb) => {
     console.log(mainString);
-    var newString = '', currentIndex, newIndex;
 
-    myString = mainString.toLowerCase().split('');
-    var alphabet = 'abcdefghijklmnopqrstuvwxyz'.split('');
+    let newString = '', currentIndex, newIndex;
 
-    var index = 0;
+    let myString = mainString.toLowerCase().split('');
+    let alphabet = 'abcdefghijklmnopqrstuvwxyz'.split('');
+
+    let index = 0;
     myString.map((val) => {
         if (!alphabet.includes(val)) {
             newString += val;
@@ -20,7 +21,6 @@ const caesarCipher = (mainString, num, cb) => {
         if (newIndex < 0) newIndex += 26;
 
         if (mainString.charAt(index) == val.toUpperCase()) {
-            console.log('Uppercase');
             newString += alphabet[newIndex].toUpperCase();
         } else {
             newString += alphabet[newIndex];
@@ -32,7 +32,7 @@ const caesarCipher = (mainString, num, cb) => {
     cb(newString);
 };
 
-caesarCipher('Zoo Keeper', -1, (result) => {
+caesarCipher('Bqq Mggrgt', -55, (result) => {
     console.log('Result is: ' + result);
 });
 

caesarCipher.js

@@ -0,0 +1,2 @@
+This is first line.
+This another line.

file.txt

@@ -0,0 +1,9 @@
+let fs = require('fs');
+fs.readFile('./file.txt', 'utf8', (err, data) => {
+    if (err) {
+        console.log('Error is: ' + err);
+    } else {
+        let array = data.split('\n');
+        console.log(array);
+    }
+});

fileRead.js

@@ -0,0 +1,110 @@
+oneTimePadMethodEncryption = (message, oneTimePad, cb) => {
+    let lowerCaseCharacterList = 'abcdefghijklmnopqrstuvwxyz'.split('');
+    let upperCaseCharacterList = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'.split('');
+    let length = message.length;
+    let encryptedMessage = '';
+
+    if (length > oneTimePad.length) {
+        return cb('Length of oneTimePad is smaller than the message length.', null);
+    }
+
+    for (let index = 0; index < message.length; index ++) {
+
+        let messageCharacter = message.charAt(index);
+        let oneTimePadCharacter = oneTimePad.charAt(index);
+        let messageCharacterIndex, oneTimePadCharacterIndex;
+        let newCharacter, newCharacterIndex;
+
+        if (messageCharacter == messageCharacter.toUpperCase()) {
+            messageCharacterIndex = upperCaseCharacterList.indexOf(messageCharacter) + 1;
+        } else {
+            messageCharacterIndex = lowerCaseCharacterList.indexOf(messageCharacter) + 1;
+        }
+
+        if (oneTimePadCharacter == oneTimePadCharacter.toUpperCase()) {
+            oneTimePadCharacterIndex = upperCaseCharacterList.indexOf(oneTimePadCharacter) + 1;
+        } else {
+            oneTimePadCharacterIndex = lowerCaseCharacterList.indexOf(oneTimePadCharacter) + 1;
+        }
+
+        newCharacterIndex = (messageCharacterIndex + oneTimePadCharacterIndex) % 26;
+
+        // newCharacterIndex --;
+        if (newCharacterIndex <= 0) newCharacterIndex += 25;
+
+        newCharacter = (messageCharacter == messageCharacter.toUpperCase()) ? upperCaseCharacterList[newCharacterIndex] : lowerCaseCharacterList[newCharacterIndex];
+        console.log(messageCharacter + '(' + messageCharacterIndex + ') ' + oneTimePadCharacter + '(' + oneTimePadCharacterIndex + ') ' + newCharacter + '(' + newCharacterIndex + ')');
+
+        encryptedMessage += newCharacter;
+    }
+
+    console.log('message    : ' + message);
+    console.log('oneTime Pad: ' + oneTimePad);
+
+    return cb(null, encryptedMessage);
+};
+
+oneTimePadMethodDecryption = (message, oneTimePad, cb) => {
+    let lowerCaseCharacterList = 'abcdefghijklmnopqrstuvwxyz'.split('');
+    let upperCaseCharacterList = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'.split('');
+    let length = message.length;
+    let encryptedMessage = '';
+
+    if (length > oneTimePad.length) {
+        return cb('Length of oneTimePad is smaller than the message length.', null);
+    }
+
+    for (let index = 0; index < message.length; index ++) {
+
+        let messageCharacter = message.charAt(index);
+        let oneTimePadCharacter = oneTimePad.charAt(index);
+        let messageCharacterIndex, oneTimePadCharacterIndex;
+        let newCharacter, newCharacterIndex;
+
+        if (messageCharacter == messageCharacter.toUpperCase()) {
+            messageCharacterIndex = upperCaseCharacterList.indexOf(messageCharacter);
+        } else {
+            messageCharacterIndex = lowerCaseCharacterList.indexOf(messageCharacter);
+        }
+
+        // messageCharacterIndex ++;
+
+        if (oneTimePadCharacter == oneTimePadCharacter.toUpperCase()) {
+            oneTimePadCharacterIndex = upperCaseCharacterList.indexOf(oneTimePadCharacter);
+        } else {
+            oneTimePadCharacterIndex = lowerCaseCharacterList.indexOf(oneTimePadCharacter);
+        }
+
+        oneTimePadCharacterIndex ++;
+
+        newCharacterIndex = (messageCharacterIndex - oneTimePadCharacterIndex);
+        if (newCharacterIndex < 0) newCharacterIndex = newCharacterIndex  + 26;
+
+
+        newCharacter = (messageCharacter == messageCharacter.toUpperCase()) ? upperCaseCharacterList[newCharacterIndex] : lowerCaseCharacterList[newCharacterIndex];
+        console.log(messageCharacter + '(' + messageCharacterIndex + ') ' + oneTimePadCharacter + '(' + oneTimePadCharacterIndex + ') ' + newCharacter + '(' + newCharacterIndex + ')');
+
+        encryptedMessage += newCharacter;
+    }
+
+    console.log('message    : ' + message);
+    console.log('oneTime Pad: ' + oneTimePad);
+
+    return cb(null, encryptedMessage);
+};
+
+oneTimePadMethodEncryption('M', 'M', (err, encryptedMessage) => {
+    if (err) {
+        console.log(err);
+    } else {
+        console.log('Encrypted Message: ' + encryptedMessage);
+        console.log('----------------------------------------------------------------------------------------');
+        oneTimePadMethodDecryption(encryptedMessage, 'M', (err, decryptedMessage) => {
+            if (err) {
+                console.log(err);
+            } else {
+                console.log('Decrypted Message: ' + decryptedMessage)   ;
+            }
+        });
+    }
+});