crypto-keygen-suite/keyGen/ciphers/columnartranspositionciphergenerator.js

Key generation utilities for cryptographic operations. YES I RENAMED IT. SIX STATE PROTOCOL!!! See its folder for all <3

import yargs from 'yargs/yargs';
import { hideBin } from 'yargs/helpers';

function columnarTranspositionEncrypt(message, key) {
  const numColumns = key.length;
  const numRows = Math.ceil(message.length / numColumns);
  const grid = Array.from({ length: numRows }, () => Array(numColumns).fill(''));

  for (let i = 0; i < message.length; i++) {
    const row = Math.floor(i / numColumns);
    const col = i % numColumns;
    grid[row][col] = message[i];
}

      const keyOrder = Array.from(key).map((char, index) => ({ char, index }))
        .sort((a, b) => a.char.localeCompare(b.char))
        .map(item => item.index);


        let result = '';
        for (const col of keyOrder) {
            for (let row = 0; row < numRows; row++) {
                if (grid[row][col]) {
                    result += grid[row][col];
                }
            }
        }
    
        return result;
    }

    function columnarTranspositionDecrypt(message, key) {
      const numColumns = key.length;
      const numRows = Math.ceil(message.length / numColumns);
      const grid = Array.from({ length: numRows }, () => Array(numColumns).fill(''));
  

      const keyOrder = Array.from(key).map((char, index) => ({ char, index }))
          .sort((a, b) => a.char.localeCompare(b.char))
          .map(item => item.index);
  
      let index = 0;
      for (const col of keyOrder) {
          for (let row = 0; row < numRows; row++) {
              if (index < message.length) {
                  grid[row][col] = message[index++];
              }
          }
      }
  
      let result = '';
      for (let row = 0; row < numRows; row++) {
          for (let col = 0; col < numColumns; col++) {
              result += grid[row][col];
          }
      }
  
      return result;
  }

  const argv = yargs(hideBin(process.argv))
      .option('message', {
          alias: 'm',
          description: 'The message to encrypt or decrypt',
          type: 'string',
          demandOption: true
      })
      .option('key', {
          alias: 'k',
          description: 'The key used for encryption or decryption',
          type: 'string',
          demandOption: true
      })
      .option('encrypt', {
          alias: 'e',
          description: 'Set to true to encrypt, false to decrypt',
          type: 'boolean',
          default: true
      })
      .help()
      .argv;
  
  const result = argv.encrypt
      ? columnarTranspositionEncrypt(argv.message, argv.key)
      : columnarTranspositionDecrypt(argv.message, argv.key);
  
  console.log('Result:', result);