import { getBytes } from "./data.js"; import { throwArgumentError } from "./errors.js"; import { toBigInt, toHex } from "./maths.js"; import type { BytesLike } from "./index.js"; const Alphabet = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz"; let Lookup: null | Record = null; function getAlpha(letter: string): bigint { if (Lookup == null) { Lookup = { }; for (let i = 0; i < Alphabet.length; i++) { Lookup[Alphabet[i]] = BigInt(i); } } const result = Lookup[letter]; if (result == null) { throwArgumentError(`invalid base58 value`, "letter", letter); } return result; } const BN_0 = BigInt(0); const BN_58 = BigInt(58); /** * Encode %%value%% as Base58-encoded data. */ export function encodeBase58(_value: BytesLike): string { let value = toBigInt(getBytes(_value)); let result = ""; while (value) { result = Alphabet[Number(value % BN_58)] + result; value /= BN_58; } return result; } /** * Decode the Base58-encoded %%value%%. */ export function decodeBase58(value: string): Uint8Array { let result = BN_0; for (let i = 0; i < value.length; i++) { result *= BN_58; result += getAlpha(value[i]); } return getBytes(toHex(result)); }