base58

base58.ts

function base58(encodeMap) {
  function base58encode(int64: string): string {
    let num = BigInt(int64)
    const base = 58n

    let res = ''
    while (num >= base) {
      res += encodeMap[num % base]
      num = num / base
    }
    res += encodeMap[num]
    return res
      .split('')
      .reverse()
      .join('')
  }

  /**
   * base58 to int64
   * @param {string} base58
   * @returns {string} int64
   */
  function base58decode(base58: string): string {
    let num = 0n
    for (let i = 0; i < base58.length; i++) {
      num = num * 58n + BigInt(encodeMap.indexOf(base58[i]))
    }
    return num.toString()
  }
  return {
    encode: base58encode,
    decode: base58decode,
  }
}

export default base58