@zyther/scode-core

Hand-coding tools for classic ciphers — Enigma, Morse, Polybius, Vigenère, Bacon, and more.

Install

npm install @zyther/scode-core

Usage

import { encode, decode, format_str } from "@zyther/scode-core"

// Encode
const result = encode({
  message: format_str("hello world"),
  pattern: "¬",             // Morse code
})

console.log(result.encrypted) // "-.-. .... . .-.. .-.. ---"
console.log(result.config)    // "" (no config needed for Morse)

// Decode
const decoded = decode({
  encrypted: result.encrypted,
  pattern: "¬",
  config: result.config,
})

console.log(decoded.message)  // "HELLOWORLD"

API

encode(options)

Encodes a plain message using the given cipher pattern.

| Option | Type | Description | | --------- | -------- | ------------------------------------ | | message | string | The plain text to encode. | | pattern | string | The cipher pattern (e.g. ¬, ?). |

Returns: { encrypted: string, config: string, pattern: string }

Throws if message is empty or pattern is invalid.

decode(options)

Decodes an encrypted message back to plain text.

| Option | Type | Description | | ----------- | -------- | ------------------------------------------------ | | encrypted | string | The encoded message. | | pattern | string | The pattern used during encoding. | | config | string | Configuration string emitted by encode (optional). |

Returns: { message: string }

Throws if encrypted is empty, pattern is invalid, or config doesn't match what the pattern requires.

listCiphers()

Returns metadata for every cipher available in the package.

import { listCiphers } from "@zyther/scode-core"

listCiphers()
// → [
//     { name: "Morse",  symbol: "¬", description: "Morse code." },
//     { name: "Enigma", symbol: "?", description: "WWII Enigma machine." },
//     ...
//   ]

validatePattern(pattern)

Returns true if the pattern is syntactically valid.

validatePattern("¬")   // true
validatePattern("&§")  // true
validatePattern("X")   // false
validatePattern("")    // false

validateConfig(pattern, config)

Returns true if the configuration string satisfies what the pattern requires.

validateConfig("|", "abcdefghij")    // true  (Vigenère needs a 10-char key)
validateConfig("|", null)            // false
validateConfig("¬", null)            // true  (Morse needs no config)

Cipher patterns

A pattern is a string of cipher symbols applied in sequence. Patterns are applied right-to-left during encoding (the last symbol is the innermost encoding), so decoding reverses the order.

| Symbol | Cipher | Needs config | | ------ | ----------------------------- | :----------: | | $ | SCSimply — key level | no | | ¢ | SCSimply — key_m level | no | | @ | SCSimply — a_num level | no | | ¬ | Morse | no | | £ | Binary | no | | # | Polybius square | yes | | * | Navajo | no | | ? | Enigma machine | yes | | \| | Vigenère | yes | | § | Frama | yes | | ₢ | Bacon | no | | & | Mutation — reciprocity | no | | ~ | Mutation — decalation | yes | | : | Order — reverse | no | | ° | Order — random | yes |

Composition examples:

¬       Morse only
?       Enigma only
&§      Mutation.reciprocity, then Frama
°|#     Order.random, then Vigenère, then Polybius

Symbols marked as restricted (¬, #, *) can only appear at the end of a pattern — they transform the whole message and would break composition.

Example: chained encoding

import { encode, decode, format_str } from "@zyther/scode-core"

const { encrypted, config, pattern } = encode({
  message: format_str("meet me at dawn"),
  pattern: "?|",            // Enigma, then Vigenère
})

console.log(encrypted)
console.log(config)         // space-separated tokens needed for decode

const { message } = decode({ encrypted, pattern, config })
console.log(message)        // "MEETMEATDAWN"

Exports

// Functions
encode, decode, listCiphers, validatePattern, validateConfig

// Constants
CIPHERS

// Types
EncodeOptions, EncodeResult,
DecodeOptions, DecodeResult,
CipherInfo

Related

• Web app — scode.zyther.dev
• Source — github.com/zytherdev/scode

License

MIT © Zyther Dev