cipher-collection/src/wolfenbuetteler.js

Zero-dependency modular cipher collection including all well-known and often used ciphers

import { substitute } from './helpers/substitute'

export default (input, options = {}) => substitute(input, retrieveOptions(options))

const retrieveOptions = options => ({
  mapping: DEFAULT_MAPPING,
  caseSensitive: options.onlyUpperCase
})

const DEFAULT_MAPPING = {
  'A': 'M',
  'E': 'K',
  'I': 'D',
  'O': 'T',
  'U': 'H'
}