feat: add sign message component

Signed-off-by: Gregory Hill <[email protected]>

packages/sats-wagmi/src/connectors/mm-snap.ts

@@ -198,8 +198,26 @@ class MMSnapConnector extends SatsConnector {
     return pubkey.toString('hex');
   }
 
-  signMessage(): Promise<string> {
-    throw new Error('Not implemented');
+  async signMessage(message: string): Promise<string> {
+    try {
+      return (await ethereum.request({
+        method: 'wallet_invokeSnap',
+        params: {
+          snapId,
+          request: {
+            method: 'btc_signMessage',
+            params: {
+              message,
+              hdPath: getDefaultBip32Path(DEFAULT_SCRIPT_TYPE, this.snapNetwork)
+            }
+          }
+        }
+      })) as string;
+    } catch (err: any) {
+      const error = new SnapError(err?.message || 'Could not sign message');
+
+      throw error;
+    }
   }
 
   async signInput(inputIndex: number, psbt: Psbt) {

packages/sats-wagmi/src/hooks/index.ts

@@ -5,3 +5,4 @@ export * from './useBalance';
 export * from './useFeeRate';
 export * from './useFeeEstimate';
 export * from './useSendTransaction';
+export * from './useSignMessage';

packages/sats-wagmi/src/hooks/useSendTransaction.tsx

@@ -5,7 +5,7 @@ import { useSatsWagmi } from '../provider';
 import { useAccount } from './useAccount';
 
 type UseSendTransactionProps = Omit<
-  UseMutationOptions<any, unknown, { to: string; value: bigint }, unknown>,
+  UseMutationOptions<string | undefined, unknown, { to: string; value: bigint }, unknown>,
   'mutationKey' | 'mutationFn'
 >;
 

packages/sats-wagmi/src/hooks/useSignMessage.tsx

@@ -0,0 +1,33 @@
+import { useMutation, UseMutationOptions } from '@tanstack/react-query';
+
+import { useSatsWagmi } from '../provider';
+
+import { useAccount } from './useAccount';
+
+type UseSignMessageProps = Omit<
+  UseMutationOptions<string | undefined, unknown, { message: string }, unknown>,
+  'mutationKey' | 'mutationFn'
+>;
+
+const useSignMessage = (props: UseSignMessageProps = {}) => {
+  const { connector } = useSatsWagmi();
+  const { address } = useAccount();
+
+  const { mutate, mutateAsync, ...result } = useMutation({
+    mutationKey: ['sats-sign-message', address],
+    mutationFn: async ({ message }: { message: string }) => {
+      if (!connector) return undefined;
+
+      return await connector.signMessage(message);
+    },
+    ...props
+  });
+
+  return {
+    ...result,
+    signMessage: mutate,
+    signMessageAsync: mutateAsync
+  };
+};
+
+export { useSignMessage };

playgrounds/vite-react/src/App.tsx

@@ -6,7 +6,8 @@ import {
   useBalance,
   useConnect,
   useDisconnect,
-  useSendTransaction
+  useSendTransaction,
+  useSignMessage
   // useWaitForTransactionReceipt,
 } from '@gobob/sats-wagmi';
 
@@ -23,6 +24,7 @@ function App() {
     <>
       <Account />
       <Connect />
+      <SignMessage />
       <Balance />
       <SendTransaction />
     </>
@@ -71,6 +73,30 @@ function Connect() {
   );
 }
 
+function SignMessage() {
+  const { data, signMessage } = useSignMessage();
+
+  return (
+    <div>
+      <h2>Sign Message</h2>
+
+      <form
+        onSubmit={(event) => {
+          event.preventDefault();
+          const formData = new FormData(event.target as HTMLFormElement);
+
+          signMessage({ message: formData.get('message') as string });
+        }}
+      >
+        <input name='message' />
+        <button type='submit'>Sign Message</button>
+      </form>
+
+      {data}
+    </div>
+  );
+}
+
 function Balance() {
   const { data: account_ } = useBalance();