From 2122bd506587fef0306b43240473ba6b3a5672e6 Mon Sep 17 00:00:00 2001
From: Otniel Nicola <otniel@axlabs.com>
Date: Mon, 29 Dec 2025 16:03:57 +0200
Subject: [PATCH] feat: Add N3 examples of MessageBridge usage in JS

---
 bridge/messaging-bridge/evm-to-n3.md | 48 +++++++++++++++++-----------
 bridge/messaging-bridge/n3-to-evm.md | 15 ++++++---
 2 files changed, 40 insertions(+), 23 deletions(-)

diff --git a/bridge/messaging-bridge/evm-to-n3.md b/bridge/messaging-bridge/evm-to-n3.md
index 3992307..1e4b222 100644
--- a/bridge/messaging-bridge/evm-to-n3.md
+++ b/bridge/messaging-bridge/evm-to-n3.md
@@ -122,29 +122,41 @@ Once the result is transferred, it can be read on the EVM chain.
 ## Example Implementation (JavaScript)
 
 ```javascript
-const { ethers } = require('ethers');
+const {ethers} = require('ethers');
 
 // Define the target contract address and the account address to check the balance for.
 const neoTokenContractAddress = "0xef4073a0f2b305a38ec4050e4d3d28bc40ea63f5"; // Neo token address on N3
 const targetAddress = "0xabcdefabcdefabcdefabcdefabcdefabcdefabcd"; // Address to check the balance for
 
-function exampleFunc() {
-    // TBD: Serialize an N3 method call using Javascript
-    // Invoke the N3 MessageBridge contract's function serializeN3MethodCall() to get the bytes needed.
-    // const rawMessage = n3MessageBridge.serializeN3MethodCall(target, method, callFlags, args);
-    const rawMessage = "0x400428141418e358c565207768eae8d237241e85d3e9f1cb280573746f72652101024002210101210440a87c68";
-
-    const storeResult = true;
-    const sendingFee = ethers.parseEther("0.1");
-    await evmMessageBridge.connect(sender).sendExecutableMessage(rawMessage, storeResult, {value: sendingFee, maxFeePerGas, maxPriorityFeePerGas});
-
-    // Wait until the message arrives on N3...
-
-    // TBD: Execute message on N3 using Javascript
-    // Invoke the method executeMessage() on the MessageBridge contract on N3 using the assigned message nonce when the message was sent.
-
-    // TBD: Send the result back from N3 to EVM
-    // Invoke the method sendResultMessage() on the MessageBridge contract on N3 using the assigned message nonce when the message was sent initially.
+async function exampleFunc() {
+  // Assume evmMessageBridge and n3MessageBridge are already instantiated contract objects
+  
+  // Serialize an N3 method call using the N3 MessageBridge
+  const rawMessage = await n3MessageBridge.serializeCall(
+      neoTokenContractAddress, // Target contract (NEO token)
+      'balanceOf', // Method to call
+      15, // CallFlags.ALL - can be adjusted as needed
+      [targetAddress] // Arguments
+  );
+  // const rawMessage = "0x400428141418e358c565207768eae8d237241e85d3e9f1cb280573746f72652101024002210101210440a87c68"; // Example serialized message
+
+  const storeResult = true;
+  let sendingFee = ethers.parseEther("0.1");
+  const nonce = await evmMessageBridge.connect(evmSender)
+    .sendExecutableMessage(rawMessage, storeResult, {value: sendingFee, maxFeePerGas, maxPriorityFeePerGas});
+
+  // Wait until the message arrives on N3...
+
+  // Execute message on N3 using Javascript
+  await n3MessageBridge.executeMessage(nonce);
+
+  // Send the result back from N3 to EVM
+  sendingFee = await n3MessageBridge.sendingFee();
+  const params: SendResultMessageParams = {
+    nonce: nonce,
+    maxFee: sendingFee
+  };
+  await n3MessageBridge.sendResultMessage(params);
 }
 ```
 
diff --git a/bridge/messaging-bridge/n3-to-evm.md b/bridge/messaging-bridge/n3-to-evm.md
index 74f6de5..3c9a1c9 100644
--- a/bridge/messaging-bridge/n3-to-evm.md
+++ b/bridge/messaging-bridge/n3-to-evm.md
@@ -137,7 +137,7 @@ Once the result is transferred, it can be read on-chain on N3.
 ## Example Implementation (JavaScript)
 
 ```javascript
-const { ethers } = require('ethers');
+const {ethers} = require('ethers');
 
 // Define the Neo token contract address on EVM and target address
 const neoTokenContractAddress = "0xc28736dc83f4fd43d6fb832Fd93c3eE7bB26828f"; // Neo token address on Neo X Testnet
@@ -148,12 +148,17 @@ const erc20Interface = new ethers.Interface([
     "function balanceOf(address account) view returns (uint256)"
 ]);
 
-function exampleFunc() {
+async function exampleFunc() {
     const encodedMessage = getEncodedMessage("0xc28736dc83f4fd43d6fb832Fd93c3eE7bB26828f", "0xabcdefabcdefabcdefabcdefabcdefabcdefabcd");
 
-    // TBD: Send message on N3 using Javascript
-    // Invoke the method sendExecutableMessage on the MessageBridge contract on N3 using the encodedMessage bytes.
-    // const nonce = n3MessageBridge.sendExecutableMessage(messageBytes, true, sender, messageFee);
+    // Send message on N3 using Javascript
+    const sendingFee = await messageBridge.sendingFee();
+    const params: SendExecutableMessageParams = {
+        encodedMessage,
+        true, // storeResult
+        maxFee: sendingFee
+    };
+    await messageBridge.sendExecutableMessage(params)
 
     // Wait until the message arrives on the EVM chain...