		@@ -1,74 +0,42 @@
		// TODO: integrate privacy calculations, group by address, avoid linking multiple addresses together
		let accumulative = require('./accum')
		let blackjack = require('./blackjack')

		// XXX: these are based on pubKeyHash estimates, used to improve performance
		var TX_EMPTY_SIZE = 8
		var TX_INPUT_BASE = 40 + 2
		var TX_INPUT_PUBKEYHASH = 106
		var TX_OUTPUT_BASE = 8 + 1
		var TX_OUTPUT_PUBKEYHASH = 25
		// TODO
		// function groupByRelation (utxos) {
		// let txoMap = {}
		// let result = []
		//
		// // group by address/script
		// utxos.forEach((utxo) => {
		// let key = utxo.address \|\| utxo.script
		//
		// // no relation known, use as is
		// if (!key) return result.push(utxo)
		//
		// // else, append relation via key
		// if (!txoMap[key]) txoMap[key] = []
		// txoMap[key].push(utxo)
		// })
		//
		// for (let key in txoMap) {
		// let group = txoMap[key]
		//
		// // summate 'grouping' value
		// group.value = group.reduce((a, x) => a + x.value, 0)
		// result.push(group)
		// }
		//
		// return result
		// }

		function estimateRelayFee (byteLength, feeRate) {
		return byteLength * feeRate
		}
		module.exports = function coinSelect (utxos, outputs, feeRate) {
		// order by descending value
		utxos = utxos.concat().sort((a, b) => b.value - a.value)

		module.exports = function coinSelect (unspents, outputs, feeRate) {
		// sort by descending value
		var sorted = unspents.concat().sort(function (o1, o2) {
		return o2.value - o1.value
		})
		// attempt to use the blackjack strategy first (no change output)
		let base = blackjack(utxos, outputs, feeRate)
		if (base.inputs) return base

		var byteLength = TX_EMPTY_SIZE
		var target = 0

		outputs.forEach(function (output) {
		byteLength += TX_OUTPUT_BASE + (output.script ? output.script.length : TX_OUTPUT_PUBKEYHASH)
		target += output.value
		})

		var accum = 0

		for (var i = 0; i < sorted.length; ++i) {
		var unspent = sorted[i]

		// TODO: an estimate is used because of missing signature data
		byteLength += TX_INPUT_BASE + TX_INPUT_PUBKEYHASH
		accum += unspent.value

		// ignore fees until we have the minimum amount
		if (accum < target) continue

		var baseFee = estimateRelayFee(byteLength, feeRate)
		var total = target + baseFee

		// continue until we can afford the base fee
		if (accum < total) continue
		var inputs = sorted.slice(0, i + 1)

		var feeWithChange = estimateRelayFee(byteLength + TX_OUTPUT_BASE + TX_OUTPUT_PUBKEYHASH, feeRate)
		var totalWithChange = target + feeWithChange

		// can we afford a change output?
		if (accum >= totalWithChange) {
		var remainderWithChange = accum - totalWithChange

		return {
		fee: feeWithChange,
		inputs: inputs,
		remainder: remainderWithChange
		}
		}

		var remainder = accum - total

		return {
		fee: baseFee + remainder,
		inputs: inputs,
		remainder: 0
		}
		}

		return {
		fee: estimateRelayFee(byteLength, feeRate),
		inputs: null
		}
		// else, try the accumulative strategy
		return accumulative(utxos, outputs, feeRate)
		}

package.json

		{
		"name": "coinselect",
		"version": "2.0.1",
		"description": "A fee optimizing bitcoin input selection module",
		"version": "3.0.0",
		"description": "A transaction input selection module for bitcoin.",
		"keywords": [
		@@ -26,3 +26,6 @@ "coinselect",
		"files": [
		"index.js"
		"accumulative.js",
		"blackjack.js",
		"index.js",
		"utils.js"
		],
		@@ -44,4 +47,6 @@ "main": "index.js",
		"standard": "*",
		"tap-spec": "^4.1.1",
		"tape": "^4.5.1"
		}
		},
		"dependencies": {}
		}

README.md

		@@ -8,7 +8,7 @@ # coinselect

		A fee-optimizing, transaction input selection module for bitcoinjs-lib.
		A transaction input selection module for bitcoin.

		The code is stable.

		The module's interface/existence is not.
		The module's interface is not.

		@@ -21,8 +21,9 @@ Please let me know if you are using this package.
		``` javascript
		var coinSelect = require('coinselect')

		var feeRate = 55 // satoshis per byte
		var unspents = [
		let coinSelect = require('coinselect')
		let feeRate = 55 // satoshis per byte
		let utxos = [
		...,
		{
		txId: '...',
		vout: 0,
		...,
		@@ -32,3 +33,3 @@ value: 10000
		]
		var outputs = [
		let targets = [
		...,
		@@ -41,17 +42,23 @@ {

		var result = coinselect(unspents, outputs, feeRate)
		// ...
		let { inputs, outputs, fee } = coinSelect(utxos, targets, feeRate)

		// the accumulated fee is always returned
		console.log(result.fee)
		// the accumulated fee is always returned for analysis
		console.log(fee)

		// .inputs may be null if not enough funds exist
		if (!result.inputs) return
		// .inputs and .outputs will be undefined if no solution was found
		if (!inputs \|\| !outputs) return

		// success!
		var txb = new bitcoin.TransactionBuilder()
		let txb = new bitcoin.TransactionBuilder()

		// is a change output non-dust?
		if (result.remainder > 5460) {
		txb.addOutput(changeAddress, result.remainder)
		}
		inputs.forEach(input => txb.addInput(input.txId, input.vout))
		outputs.forEach(output => {
		// watch out, outputs may have been added that you need to provide
		// an output address/script for
		if (!output.address) {
		output.address = wallet.getChangeAddress()
		}

		txb.addOutput(output.address, output.value)
		})
		```
		@@ -58,0 +65,0 @@

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