const jsonRpc = require('../../common/json-rpc')

const path = require('path')
const options = require('../../../options')

const BN = require('../../../bn')
const E = require('../../../error')

const DEFAULT_PORT = 8232
const SATOSHI_SHIFT = 8

const configPath = path.resolve(options.blockchainDir, 'zcash.conf')
const config = jsonRpc.parseConf(configPath)

const rpcConfig = {
  username: config.rpcuser,
  password: config.rpcpassword,
  port: config.rpcport || DEFAULT_PORT
}

function fetch (method, params) {
  return jsonRpc.fetch(rpcConfig, method, params)
}

function checkCryptoCode (cryptoCode) {
  if (cryptoCode !== 'ZEC') return Promise.reject(new Error('Unsupported crypto: ' + cryptoCode))
  return Promise.resolve()
}

function accountBalance (acount, cryptoCode, confirmations) {
  return checkCryptoCode(cryptoCode)
  .then(() => fetch('getbalance', ['', confirmations]))
  .then(r => BN(r).shift(SATOSHI_SHIFT).round())
}

// We want a balance that includes all spends (0 conf) but only deposits that
// have at least 1 confirmation. getbalance does this for us automatically.
function balance (account, cryptoCode) {
  return accountBalance(account, cryptoCode, 1)
}

function sendCoins (account, address, cryptoAtoms, cryptoCode) {
  const confirmations = 1
  const bitcoins = cryptoAtoms.shift(-SATOSHI_SHIFT).toFixed(8)

  return checkCryptoCode(cryptoCode)
  .then(() => fetch('sendfrom', [address, bitcoins, confirmations]))
  .catch(err => {
    if (err.code === -6) throw new E.InsufficientFundsError()
    throw err
  })
}

function newAddress (account, info) {
  return checkCryptoCode(info.cryptoCode)
  .then(() => fetch('getnewaddress'))
}

function addressBalance (address, confs) {
  return fetch('getreceivedbyaddress', [address, confs])
  .then(r => BN(r).shift(SATOSHI_SHIFT).round())
}

function confirmedBalance (address, cryptoCode) {
  return checkCryptoCode(cryptoCode)
  .then(() => addressBalance(address, 1))
}

function pendingBalance (address, cryptoCode) {
  return checkCryptoCode(cryptoCode)
  .then(() => addressBalance(address, 0))
}

function getStatus (account, toAddress, requested, cryptoCode) {
  return checkCryptoCode(cryptoCode)
  .then(() => confirmedBalance(toAddress, cryptoCode))
  .then(confirmed => {
    if (confirmed.gte(requested)) return {status: 'confirmed'}

    return pendingBalance(toAddress, cryptoCode)
    .then(pending => {
      if (pending.gte(requested)) return {status: 'authorized'}
      if (pending.gt(0)) return {status: 'insufficientFunds'}
      return {status: 'notSeen'}
    })
  })
}

function newFunding (account, cryptoCode) {
  return checkCryptoCode(cryptoCode)
  .then(() => {
    const promises = [
      accountBalance(account, cryptoCode, 0),
      accountBalance(account, cryptoCode, 1),
      newAddress(account, {cryptoCode})
    ]

    return Promise.all(promises)
  })
  .then(([fundingPendingBalance, fundingConfirmedBalance, fundingAddress]) => ({
    fundingPendingBalance,
    fundingConfirmedBalance,
    fundingAddress
  }))
}

module.exports = {
  balance,
  sendCoins,
  newAddress,
  getStatus,
  newFunding
}