From 9b7f34f12e105a4228e7435bb68d717835f46e1b Mon Sep 17 00:00:00 2001
From: nuno <hi@nunoalexandre.com>
Date: Thu, 21 Jul 2022 12:13:27 +0200
Subject: [PATCH] Fix and test AddPool encoding

---
 Cargo.lock                        |  1 +
 pallets/connectors/Cargo.toml     |  1 +
 pallets/connectors/src/lib.rs     |  5 ++-
 pallets/connectors/src/message.rs | 52 ++++++++++++++++++++++++-------
 4 files changed, 47 insertions(+), 12 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 3bd72c9281..197d41483a 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -5953,6 +5953,7 @@ dependencies = [
  "frame-benchmarking",
  "frame-support",
  "frame-system",
+ "hex",
  "orml-tokens",
  "orml-traits",
  "pallet-balances",
diff --git a/pallets/connectors/Cargo.toml b/pallets/connectors/Cargo.toml
index f2a8f397c6..5f7b8aad86 100644
--- a/pallets/connectors/Cargo.toml
+++ b/pallets/connectors/Cargo.toml
@@ -31,6 +31,7 @@ common-types = { path = "../../libs/common-types", default-features = false, opt
 runtime-common = { path = "../../runtime/common", default-features = false, optional = true }
 
 [dev-dependencies]
+hex = "0.4.3"
 # Substrate crates & pallets
 sp-core = { git = "https://github.com/paritytech/substrate", default-features = false , branch = "polkadot-v0.9.24" }
 sp-io = { git = "https://github.com/paritytech/substrate", default-features = false , branch = "polkadot-v0.9.24" }
diff --git a/pallets/connectors/src/lib.rs b/pallets/connectors/src/lib.rs
index 304e2bc807..0868fa5a1d 100644
--- a/pallets/connectors/src/lib.rs
+++ b/pallets/connectors/src/lib.rs
@@ -59,7 +59,10 @@ pub mod pallet {
 			+ Copy
 			+ HasCompact
 			+ MaxEncodedLen
-			+ core::fmt::Debug;
+			+ core::fmt::Debug
+			+ Encode
+			+ Decode
+			+ Into<u64>;
 
 		type TrancheId: Member
 			+ Parameter
diff --git a/pallets/connectors/src/message.rs b/pallets/connectors/src/message.rs
index 49b6617016..0acc9bd8d7 100644
--- a/pallets/connectors/src/message.rs
+++ b/pallets/connectors/src/message.rs
@@ -2,18 +2,32 @@ use crate::*;
 
 #[derive(Decode, Clone, PartialEq, TypeInfo)]
 #[cfg_attr(feature = "std", derive(Debug))]
-pub enum Message<PoolId> {
+pub enum Message<PoolId> where PoolId: Encode + Decode {
 	Invalid,
 	AddPool { pool_id: PoolId }, // More to come...
 }
 
-impl<PoolId> Encode for Message<PoolId> {
+impl<PoolId: Encode + Decode> Message<PoolId> {
+	fn call_type(&self) -> u8 {
+		match self {
+			Self::Invalid => 0,
+			Self::AddPool { .. }  => 1,
+		}
+	}
+}
+
+impl<PoolId: Encode + Decode> Encode for Message<PoolId> {
 	fn encode(&self) -> Vec<u8> {
 		match self {
-			Message::Invalid => vec![0u8],
-			Message::AddPool { pool_id: _ } => {
-				let mut message: Vec<u8> = vec![0u8];
-				message.append(&mut vec![1, 2, 3]); //todo(nuno): &mut pool_id.as_bytes().to_vec());
+			Message::Invalid => vec![self.call_type()],
+			Message::AddPool { pool_id } => {
+				let mut message: Vec<u8> = vec![];
+				message.push(self.call_type());
+				//todo(nuno): &mut pool_id.as_bytes().to_vec());
+				// to do this, we need to need a stricter PoolId bound to be able to convert it to byte array
+				let mut encoded_pool_id = pool_id.encode();
+				encoded_pool_id.reverse();
+				message.append(&mut encoded_pool_id);
 				message
 			}
 		}
@@ -24,6 +38,7 @@ impl<PoolId> Encode for Message<PoolId> {
 mod tests {
 	use crate::Message;
 	use codec::Encode;
+	use hex::FromHex;
 
 	type PoolId = u64;
 
@@ -32,14 +47,29 @@ mod tests {
 
 		#[test]
 		fn invalid() {
-			let encoded = Message::<PoolId>::Invalid.encode();
-			assert_eq!(encoded, vec![0])
+			let msg = Message::<PoolId>::Invalid;
+			assert_eq!(msg.encode(), vec![msg.call_type()]);
+			assert_eq!(msg.encode(), vec![0]);
 		}
 
 		#[test]
-		fn add_pool() {
-			let encoded = Message::<PoolId>::AddPool { pool_id: 42 }.encode();
-			assert_eq!(encoded, vec![0, 1, 2, 3])
+		fn add_pool_0() {
+			let msg = Message::<PoolId>::AddPool { pool_id: 0 };
+			let encoded = msg.encode();
+
+			let input = "010000000000000000";
+			let expected = <[u8; 9]>::from_hex(input).expect("Decoding failed");
+			assert_eq!(encoded, expected);
+		}
+
+		#[test]
+		fn add_pool_long() {
+			let msg = Message::<PoolId>::AddPool { pool_id: 12378532 };
+			let encoded = msg.encode();
+
+			let input = "010000000000bce1a4";
+			let expected = <[u8; 9]>::from_hex(input).expect("Decoding failed");
+			assert_eq!(encoded, expected);
 		}
 	}
 }