zaddr-settle.js

const assert = require('assert');
const delay = require('delay');
const { getRpc } = require('../rpcs');
const { n } = require('../utils');
const config = require('../config');
const debug = require('consol').debugger('sideshift:pay:zaddr');

const FEE = 0.0001;

module.exports = async function payWithZaddr(paymentMethod, paymentDetails) {
  const { zcashSourceZaddr: sourceAddress } = config;
  assert(sourceAddress);

  const rpc = getRpc(paymentMethod.node);

  if (!rpc) {
    throw Object.assign(new Error(`Rpc not found for node ${paymentMethod.node}`), { sent: false });
  }

  const fetchOperastionResult = async operationId => {
    while (true) {
      const [result] = await rpc.cmdAsync('z_getoperationresult', [operationId]);

      if (!result) {
        await delay(1000);
        continue;
      }

      return result;
    }
  };

  const { amount, destination } = paymentDetails;
  const { address } = destination;

  const balanceOfSourceAddress = await rpc.cmdAsync('z_getbalance', sourceAddress);
  debug(`Source address ${sourceAddress} has a balance of ${balanceOfSourceAddress}`);

  const amountWithFeeN = n(amount).plus(FEE);

  if (n(balanceOfSourceAddress).lt(amountWithFeeN)) {
    const message = `Cant afford to send ${amount} plus ${FEE} fee. Have ${balanceOfSourceAddress}`;
    throw Object.assign(new Error(message), { sent: false });
  }

  const changeAmountN = n(balanceOfSourceAddress).minus(amountWithFeeN);

  const sendManyAmunts = [{ address, amount }, { address: sourceAddress, amount: changeAmountN }];
  debug('Will send', { sendManyAmunts });

  const operationId = await rpc.cmdAsync('z_sendmany', sourceAddress, sendManyAmunts, 1, FEE);
  const operationResult = await fetchOperastionResult(operationId);

  assert.equal(operationResult.status, 'success');

  const { txid } = operationResult.result;
  assert(txid);

  return {
    sentAmount: amount,
    networkFee: FEE.toString(),
    tx: { txid },
  };
};