initial commit

fifo/index.js

@@ -0,0 +1,113 @@
+const csvToJson = require('convert-csv-to-json')
+const converter = require('json-2-csv')
+const fs = require('fs')
+const BN = require('bignumber.js')
+
+const txs = csvToJson.fieldDelimiter(',').getJsonFromCsv(`../Ledger.csv`)
+let utxos = []
+let dispositions = []
+
+const handleBuy = (tx, i) => {
+  const { Date: date, Asset, Received, Price } = tx
+  utxos.push({
+    Date: date,
+    Id: i,
+    Asset,
+    Amount: Received,
+    Price,
+    Remaining: new BN(Received),
+  })
+}
+
+const createDisposition = (tx, utxo, amount) => {
+  const st = new Date(tx.Date).valueOf() - new Date(utxo.Date).valueOf() < 31556926000
+  const costBasis = amount.times(utxo.Price)
+  const proceeds =  amount.times(tx.Price)
+  const gainLoss = proceeds.minus(costBasis)
+  const disposition = {
+    Date: tx.Date,
+    Asset: tx.Asset,
+    Utxo: utxo.Id,
+    Amount: amount.toFixed(8),
+    PurchasePrice: utxo.Price,
+    DateAcquired: utxo.Date,
+    SalePrice: tx.Price,
+    CostBasis: costBasis.toFixed(2),
+    Proceeds: proceeds.toFixed(2),
+    GainLoss: gainLoss.toFixed(2),
+    ShortTerm: st ? 'true' : '',
+    Tax: gainLoss.gt(0) ? gainLoss.times(st ? .24 : .15).toFixed(2) : 0
+  }
+  dispositions.push(disposition)
+}
+
+const consumeUtxos = (tx) => {
+	for (let i = 0; i < utxos.length; i++) {
+    let utxo = utxos[i]
+
+    if (!utxo) {
+      console.error(`WARNING: No utxo available! Assuming $0 cost basis:\n-Date:${tx.Date}\n-Asset: ${tx.Asset}\n-Sent: ${tx.Sent}\n-Remaining: ${tx.Remaining.toFixed(8)}\n`)
+      utxo = {
+        Date: '2017-01-01',
+        Id: -1,
+        Asset: tx.Asset,
+        Amount: tx.Remaining.toFixed(8),
+        Price: '0',
+        Remaining: tx.Remaining,
+      }
+    }
+
+		if (utxo.Asset !== tx.Asset || utxo.Remaining.isZero()) continue
+
+    if (utxo.Remaining.gte(tx.Remaining)) {
+      createDisposition(tx, utxo, tx.Remaining)
+      utxo.Remaining = utxo.Remaining.minus(tx.Remaining)
+      return
+		} else {
+      createDisposition(tx, utxo, utxo.Remaining)
+      tx.Remaining = tx.Remaining.minus(utxo.Remaining)
+			utxo.Remaining = new BN(0)
+			return consumeUtxos(tx)
+		}
+	}
+}
+
+txs.forEach((tx, i) => {
+  if (tx.Received) return handleBuy(tx, i)
+  tx.Remaining = new BN(tx.Sent)
+  return consumeUtxos(tx)
+})
+
+let balances = utxos.reduce((prev,  curr) => {
+  const asset = curr.Asset
+  if (prev[asset]) {
+    prev[asset] = prev[asset].plus(curr.Remaining)
+  } else {
+    prev[asset] = curr.Remaining
+  }
+  return prev
+}, {})
+
+utxos = utxos.map(u => ({
+  ...u,
+  Remaining: u.Remaining.toFixed(8),
+}))
+
+balances = Object.keys(balances)
+  .filter(asset => !balances[asset].isZero())
+  .map(asset => ({
+    Asset: asset,
+    balance: balances[asset].toFixed(8)
+  }))
+
+converter.json2csv(utxos).then(csv =>
+	fs.appendFileSync(`./utxos.csv`, csv)
+)
+
+converter.json2csv(dispositions).then(csv =>
+	fs.appendFileSync(`./dispositions.csv`, csv)
+)
+
+converter.json2csv(balances).then(csv =>
+	fs.appendFileSync(`./balances.csv`, csv)
+)