[wip] fix mpc taproot example

mpc-core-kit-web/mpc-core-kit-bitcoin/package.json

@@ -15,7 +15,7 @@
     "@vitejs/plugin-react": "^4.3.1",
     "@web3auth/base": "^9.4.5",
     "@web3auth/ethereum-mpc-provider": "^9.4.5",
-    "@web3auth/mpc-core-kit": "^4.1.0-alpha.0",
+    "@web3auth/mpc-core-kit": "file:web3auth-mpc-core-kit-4.0.0-alpha.1.tgz",
     "axios": "^1.7.7",
     "bitcoinjs-lib": "^6.1.5",
     "bn.js": "^5.2.1",
@@ -70,4 +70,4 @@
     "build": "tsc && vite build",
     "serve": "vite preview"
   }
-}
+}

mpc-core-kit-web/mpc-core-kit-bitcoin/src/App.tsx

@@ -44,7 +44,7 @@ let evmProvider: EthereumSigningProvider;
 if (typeof window !== "undefined") {
   coreKitInstance = new Web3AuthMPCCoreKit({
     web3AuthClientId,
-    web3AuthNetwork: WEB3AUTH_NETWORK.MAINNET,
+    web3AuthNetwork: WEB3AUTH_NETWORK.DEVNET,
     storage: window.localStorage,
     manualSync: true,
     tssLib: tssLibFrostBip340, // tssLibDkls | tssLibFrostBip340 - Taproot only

mpc-core-kit-web/mpc-core-kit-bitcoin/src/BitcoinComponent.tsx

@@ -12,7 +12,7 @@ const ECPair = ECPairFactory(ecc);
 bitcoinjs.initEccLib(ecc);
 
 const BTCValidator = (pubkey: Buffer, msghash: Buffer, signature: Buffer): boolean => {
-  return ECPair.fromPublicKey(pubkey).verify(msghash, signature);
+  return ecc.verifySchnorr(Uint8Array.from(msghash), Uint8Array.from(pubkey), Uint8Array.from(signature));
 };
 
 const uiConsole = (...args: any): void => {
@@ -77,7 +77,9 @@ export const BitcoinComponent: React.FC<BitcoinComponentProps> = ({ coreKitInsta
 
   const fetchUtxos = async (address: string) => {
     try {
-      const response = await axios.get(`https://blockstream.info/testnet/api/address/${address}/utxo`);
+      const url = `https://blockstream.info/testnet/api/address/${address}/utxo`;
+      console.log(url);
+      const response = await axios.get(url);
       return response.data.filter((utxo: { status: { confirmed: boolean } }) => utxo.status.confirmed);
     } catch (error) {
       console.error("Error fetching UTXOs:", error);
@@ -128,9 +130,9 @@ export const BitcoinComponent: React.FC<BitcoinComponentProps> = ({ coreKitInsta
       const maxFee = Math.max(...Object.values(feeResponse.data as Record<string, number>));
       const fee = Math.ceil(maxFee * 1.2); // Adding 20% buffer to the fee
 
-      if (utxo.value <= fee) {
-        throw new Error(`Insufficient funds: ${utxo.value} satoshis <= ${fee} satoshis (estimated fee)`);
-      }
+      // if (utxo.value <= fee) {
+      //   throw new Error(`Insufficient funds: ${utxo.value} satoshis <= ${fee} satoshis (estimated fee)`);
+      // }
 
       const sendAmount = amount ? parseInt(amount) : utxo.value - fee;
 

mpc-core-kit-web/mpc-core-kit-bitcoin/src/BitcoinSigner.ts

@@ -5,6 +5,7 @@ import * as bitcoinjs from "bitcoinjs-lib";
 import ECPairFactory from "ecpair";
 
 import ecc from "@bitcoinerlab/secp256k1";
+import BN from "bn.js";
 
 const ECPair = ECPairFactory(ecc);
 
@@ -21,20 +22,26 @@ export function createBitcoinJsSigner(props: { coreKitInstance: Web3AuthMPCCoreK
 }
 
 
-export function createBitcoinJsSignerBip340(props: { coreKitInstance: Web3AuthMPCCoreKit; network: networks.Network }): SignerAsync {
+export function createBitcoinJsSignerBip340(props: { coreKitInstance: Web3AuthMPCCoreKit; network: networks.Network; }): SignerAsync {
   const bufPubKey = props.coreKitInstance.getPubKeyPoint().toSEC1(secp256k1, true);
   const xOnlyPubKey = bufPubKey.subarray(1, 33);
   const keyPair = ECPair.fromPublicKey(bufPubKey);
-  const tweakedChildNode = keyPair.tweak(bitcoinjs.crypto.taggedHash("TapTweak", xOnlyPubKey));  return {
+  const tweak = bitcoinjs.crypto.taggedHash("TapTweak", xOnlyPubKey);
+  const tweakedChildNode = keyPair.tweak(tweak);
+  const pk = tweakedChildNode.publicKey;
+
+  // const pk = props.coreKitInstance.getPubKeyPoint().toSEC1(secp256k1, true);
+  return {
     sign: async (msg: Buffer) => {
       let sig = await props.coreKitInstance.sign(msg);
       return sig;
     },
     signSchnorr: async (msg: Buffer) => {
-      let sig = await props.coreKitInstance.sign(msg);
+      const keyTweak = new BN(tweak);
+      let sig = await props.coreKitInstance.sign(msg, { keyTweak });
       return sig;
     },
-    publicKey: tweakedChildNode.publicKey,
+    publicKey: pk,
     network: props.network,
   };
 }