From 626b821e2e3e8444934e443a1ddc9d1274f33ecb Mon Sep 17 00:00:00 2001
From: Polybius93 <adam.daniel.puskas@polybius-studios.com>
Date: Wed, 18 Sep 2024 14:21:37 +0200
Subject: [PATCH] feat: add function to retrieve bitcoin address from extended
 public key

---
 package.json                               |  2 +-
 src/functions/bitcoin/bitcoin-functions.ts | 22 ++++++++++++++++++++++
 src/functions/bitcoin/index.ts             |  2 ++
 3 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/package.json b/package.json
index cc888ae..58c6ea0 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "type": "module",
   "name": "dlc-btc-lib",
-  "version": "2.2.6",
+  "version": "2.2.7",
   "description": "This library provides a comprehensive set of interfaces and functions for minting dlcBTC tokens on supported blockchains.",
   "main": "dist/index.js",
   "types": "dist/index.d.ts",
diff --git a/src/functions/bitcoin/bitcoin-functions.ts b/src/functions/bitcoin/bitcoin-functions.ts
index 3ce87b4..fc466fe 100644
--- a/src/functions/bitcoin/bitcoin-functions.ts
+++ b/src/functions/bitcoin/bitcoin-functions.ts
@@ -481,3 +481,25 @@ export function ecdsaPublicKeyToSchnorr(publicKey: Buffer): Buffer {
     throw new Error('Invalid Public Key Length');
   return publicKey.subarray(1);
 }
+
+export function getBitcoinAddressFromExtendedPublicKey(
+  bitcoinExtendedPublicKey: string,
+  bitcoinNetwork: Network,
+  bitcoinAddressIndex: number,
+  paymentType: 'wpkh' | 'tr'
+): string {
+  const derivedPublicKey = deriveUnhardenedPublicKey(
+    bitcoinExtendedPublicKey,
+    bitcoinNetwork,
+    bitcoinAddressIndex
+  );
+
+  const bitcoinAddress =
+    paymentType === 'wpkh'
+      ? p2wpkh(derivedPublicKey, bitcoinNetwork).address
+      : p2tr(ecdsaPublicKeyToSchnorr(derivedPublicKey), undefined, bitcoinNetwork).address;
+
+  if (!bitcoinAddress) throw new Error('Could not create Bitcoin Address');
+
+  return bitcoinAddress;
+}
diff --git a/src/functions/bitcoin/index.ts b/src/functions/bitcoin/index.ts
index 8755d3a..80c546a 100644
--- a/src/functions/bitcoin/index.ts
+++ b/src/functions/bitcoin/index.ts
@@ -1,5 +1,6 @@
 import {
   finalizeUserInputs,
+  getBitcoinAddressFromExtendedPublicKey,
   getFeeAmount,
   getFeeRecipientAddressFromPublicKey,
   getInputIndicesByScript,
@@ -28,4 +29,5 @@ export {
   getBalance,
   getFeeRecipientAddressFromPublicKey,
   getInputIndicesByScript,
+  getBitcoinAddressFromExtendedPublicKey,
 };