feat: WIPs from code reading session 3 (#708)

programs/svm-spoke/src/instructions/handle_receive_message.rs

@@ -11,6 +11,9 @@ use crate::{
     State,
 };
 
+//TODO: we have inconsistent imports in this file, in some places referencing from source crates (SvmSpoke::id)
+// rather than importing at the top. fix overall and check other files.
+
 #[derive(Accounts)]
 #[instruction(params: HandleReceiveMessageParams)]
 pub struct HandleReceiveMessage<'info> {
@@ -44,13 +47,14 @@ pub struct HandleReceiveMessageParams {
     pub authority_bump: u8,
 }
 
+// TODO: consider refactoring this to be consistent with using free functions.
 impl<'info> HandleReceiveMessage<'info> {
     pub fn handle_receive_message(&self, params: &HandleReceiveMessageParams) -> Result<Vec<u8>> {
         // Return instruction data for the self invoked CPI based on the received message body.
         translate_message(&params.message_body)
     }
 }
-
+// TODO: ensure that CCTP blocks re-played messages sent over the bridge. i.e one pauseDeposit Call cant be replayed.
 fn translate_message(data: &Vec<u8>) -> Result<Vec<u8>> {
     match utils::get_solidity_selector(data)? {
         s if s == utils::encode_solidity_selector("pauseDeposits(bool)") => {

programs/svm-spoke/src/lib.rs

@@ -148,6 +148,7 @@ pub mod svm_spoke {
     }
 
     // CCTP methods.
+    // TODO: consider refactoring this to be consistent with using free functions.
     pub fn handle_receive_message<'info>(
         ctx: Context<'_, '_, '_, 'info, HandleReceiveMessage<'info>>,
         params: HandleReceiveMessageParams,