From db1c2e43af816966fb0596901efda6fcd5b3380c Mon Sep 17 00:00:00 2001
From: Moe Elsharif <mohammed.elsharif@gmail.com>
Date: Thu, 5 Mar 2020 15:11:57 +0100
Subject: [PATCH] adds external signing

---
 lib/signing.js | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/lib/signing.js b/lib/signing.js
index 06e6c36e..72646456 100644
--- a/lib/signing.js
+++ b/lib/signing.js
@@ -1,5 +1,7 @@
 const { Transaction } = require("ethereumjs-tx");
 const util = require("ethereumjs-util");
+const { Message, PrivateKey } = require("bitcore-lib");
+const Mnemonic = require("bitcore-mnemonic");
 
 const signTx = (keystore, pwDerivedKey, rawTx, signingAddress) => {
   if (!keystore.isDerivedKeyCorrect(pwDerivedKey)) {
@@ -59,10 +61,18 @@ const concatSig = signature => {
   return util.addHexPrefix(r.concat(s, v).toString("hex"));
 };
 
+const signTxWithSeed = (mnemonic, msg) => {
+  const mnemoniciInstance = new Mnemonic(mnemonic);
+  const privateKeyInstance = new PrivateKey(mnemoniciInstance.toHDPrivateKey());
+  const messageInstance = new Message(msg);
+  return messageInstance.sign(privateKeyInstance);
+};
+
 module.exports = {
   concatSig,
   recoverAddress,
   signMsgHash,
   signMsg,
-  signTx
+  signTx,
+  signTxWithSeed
 };