From 63bf929d817ec0af1317818bb6f04578d79e81bd Mon Sep 17 00:00:00 2001
From: Alejo Acosta <alejoacos@gmail.com>
Date: Mon, 29 Apr 2024 18:15:06 -0300
Subject: [PATCH] refactor signTransaction to use musig

---
 src.ts/quais.ts               |  5 ++++-
 src.ts/transaction/index.ts   |  4 +++-
 src.ts/wallet/index.ts        |  4 +++-
 src.ts/wallet/utxohdwallet.ts | 19 +++++++++++++------
 4 files changed, 23 insertions(+), 9 deletions(-)

diff --git a/src.ts/quais.ts b/src.ts/quais.ts
index 98db6351..5460f015 100644
--- a/src.ts/quais.ts
+++ b/src.ts/quais.ts
@@ -84,7 +84,8 @@ export {
 export {
     accessListify,
     computeAddress, recoverAddress,
-    AbstractTransaction, FewestCoinSelector
+    AbstractTransaction, FewestCoinSelector,
+    QiTransaction
 } from "./transaction/index.js";
 
 export {
@@ -120,6 +121,8 @@ export {
     encryptKeystoreJson, encryptKeystoreJsonSync,
 
     quaiHDAccountPath, qiHDAccountPath,
+
+    nobleCrypto,
 } from "./wallet/index.js";
 
 export {
diff --git a/src.ts/transaction/index.ts b/src.ts/transaction/index.ts
index 598569f3..cd1a1760 100644
--- a/src.ts/transaction/index.ts
+++ b/src.ts/transaction/index.ts
@@ -32,4 +32,6 @@ export { FewestCoinSelector } from "./coinselector-fewest.js";
 
 export type { TransactionLike } from "./abstract-transaction.js";
 
-export type {TxInput, TxOutput} from "./utxo.js";
\ No newline at end of file
+export type {TxInput, TxOutput} from "./utxo.js";
+
+export { QiTransaction } from "./qi-transaction.js";
\ No newline at end of file
diff --git a/src.ts/wallet/index.ts b/src.ts/wallet/index.ts
index b27a0f1e..121cd562 100644
--- a/src.ts/wallet/index.ts
+++ b/src.ts/wallet/index.ts
@@ -45,4 +45,6 @@ export type {
     KeystoreAccount, EncryptOptions
 } from "./json-keystore.js"
 
-export { UTXOHDWallet } from "./utxohdwallet.js";
\ No newline at end of file
+export { UTXOHDWallet } from "./utxohdwallet.js";
+
+export { nobleCrypto } from "./musig-crypto.js";
\ No newline at end of file
diff --git a/src.ts/wallet/utxohdwallet.ts b/src.ts/wallet/utxohdwallet.ts
index 4177515d..5422eb2a 100644
--- a/src.ts/wallet/utxohdwallet.ts
+++ b/src.ts/wallet/utxohdwallet.ts
@@ -386,14 +386,22 @@ export class UTXOHDWallet extends BaseWallet {
     private createMuSigSignature(tx: QiTransaction, hash: Uint8Array): string {
         const musig = MuSigFactory(nobleCrypto);
 
-        const privKeys = tx.txInputs!.map(input => {
+        // Collect private keys corresponding to the addresses of the inputs
+        const privKeysSet = new Set<string>();
+        tx.txInputs!.forEach(input => {
             const address = computeAddress(hexlify(input.pubKey));
             const utxoAddrObj = this.utxoAddresses.find(utxoAddr => utxoAddr.address === address);
-            return utxoAddrObj ? utxoAddrObj.privKey : null;
-        }).filter(privKey => privKey !== null);
+            if (!utxoAddrObj) {
+                throw new Error(`Private key not found for public key associated with address: ${address}`);
+            }
+            privKeysSet.add(utxoAddrObj.privKey);
+        });
+        const privKeys = Array.from(privKeysSet);
 
+        // Create an array of public keys corresponding to the private keys for musig aggregation
         const pubKeys: Uint8Array[] = privKeys.map(privKey => nobleCrypto.getPublicKey(getBytes(privKey!), true)).filter(pubKey => pubKey !== null) as Uint8Array[];
 
+        // Generate nonces for each public key
         const nonces = pubKeys.map(pk => musig.nonceGen({publicKey: getBytes(pk!)}));
         const aggNonce = musig.nonceAgg(nonces);
 
@@ -403,7 +411,7 @@ export class UTXOHDWallet extends BaseWallet {
             pubKeys
         );
 
-        //Each signer creates a partial signature
+        // Create partial signatures for each private key
         const partialSignatures = privKeys.map((sk, index) =>
             musig.partialSign({
                 secretKey: getBytes(sk || ''),
@@ -415,8 +423,7 @@ export class UTXOHDWallet extends BaseWallet {
 
         // Aggregate the partial signatures into a final aggregated signature
         const finalSignature = musig.signAgg(partialSignatures, signingSession);
-
-        // const isValid = schnorr.verify(finalSignature, hash, aggPublicKey);
+        
         return hexlify(finalSignature);
     }