@atomiqlabs/sdk-lib
Version:
Basic SDK functionality library for atomiq
39 lines (38 loc) • 1.63 kB
JavaScript
;
Object.defineProperty(exports, "__esModule", { value: true });
exports.blackjack = void 0;
const utils_1 = require("./utils");
// add inputs until we reach or surpass the target value (or deplete)
// worst-case: O(n)
function blackjack(utxos, outputs, feeRate, type) {
if (!isFinite(utils_1.utils.uintOrNaN(feeRate)))
return null;
let bytesAccum = utils_1.utils.transactionBytes([], outputs, type);
let inAccum = 0;
let cpfpAddFee = 0;
const inputs = [];
const outAccum = utils_1.utils.sumOrNaN(outputs);
const threshold = utils_1.utils.dustThreshold({ type });
for (let i = 0; i < utxos.length; ++i) {
const input = utxos[i];
const inputBytes = utils_1.utils.inputBytes(input);
let cpfpFee = 0;
if (input.cpfp != null && input.cpfp.txEffectiveFeeRate < feeRate)
cpfpFee = input.cpfp.txVsize * (feeRate - input.cpfp.txEffectiveFeeRate);
const fee = (feeRate * (bytesAccum + inputBytes)) + cpfpAddFee + cpfpFee;
const inputValue = utils_1.utils.uintOrNaN(input.value);
// would it waste value?
if ((inAccum + inputValue) > (outAccum + fee + threshold))
continue;
bytesAccum += inputBytes;
inAccum += inputValue;
cpfpAddFee += cpfpFee;
inputs.push(input);
// go again?
if (inAccum < outAccum + fee)
continue;
return utils_1.utils.finalize(inputs, outputs, feeRate, type, cpfpAddFee);
}
return { fee: (feeRate * bytesAccum) + cpfpAddFee };
}
exports.blackjack = blackjack;