Merge pull request #32 from LN-Zap/bitcoind-fixes

Retain decimal precision in fee conversions

src/server.tsx

@@ -81,13 +81,10 @@ function getValueFromFulfilledPromise(result: PromiseSettledResult<any>) {
   return result && result.status === "fulfilled" && result.value ? result.value : null;
 }
 
-/**
- * Helper function to multiply two fixed point numbers.
- */
-function multiplyFixedPoint(a: number, b: number, decimalPlaces: number): number {
+function customRound(number: number, decimalPlaces: number): number {
   const factor: number = Math.pow(10, decimalPlaces);
-  const product: number = Math.floor(a * factor) * Math.floor(b * factor);
-  return product / Math.pow(10, decimalPlaces);
+  const rounded: number = Math.round(number * factor) / factor;
+  return rounded;
 }
 
 // NOTE: fetch signal abortcontroller does not work on Bun.
@@ -238,7 +235,7 @@ async function fetchBitcoindFees() : Promise<FeeByBlockTarget | null> {
           var feeRate = response[i].result?.feerate;
           if (feeRate) {
             // convert the returned value to satoshis, as it's currently returned in BTC.
-            const satPerKB = multiplyFixedPoint(feeRate, 1e8, 8);
+            const satPerKB = customRound(feeRate, 1e8);
             result[target] = applyFeeMultiplier(satPerKB);
           } else {
             console.error(`Failed to fetch fee estimate from bitcoind for confirmation target ${target}`, response[i].result?.errors);