// OP_0 {scriptHash}

const bscript = require('../../script')
const types = require('../../types')
const typeforce = require('typeforce')
const OPS = require('bitcoin-ops')

function check (script) {
  const buffer = bscript.compile(script)

  return buffer.length === 34 &&
    buffer[0] === OPS.OP_0 &&
    buffer[1] === 0x20
}
check.toJSON = function () { return 'Witness scriptHash output' }

function encode (scriptHash) {
  typeforce(types.Hash256bit, scriptHash)

  return bscript.compile([OPS.OP_0, scriptHash])
}

function decode (buffer) {
  typeforce(check, buffer)

  return buffer.slice(2)
}

module.exports = {
  check: check,
  decode: decode,
  encode: encode
}