From 558905bba487361ddd904788e7383db4ca9ebdda Mon Sep 17 00:00:00 2001
From: Devin Ragotzy <devin.ragotzy@gmail.com>
Date: Mon, 14 Dec 2020 16:15:22 -0500
Subject: [PATCH] WIP: use resolve_incoming from state-res crate

---
 src/server_server.rs | 64 +++++++++++++++++++++++++++++++++++---------
 1 file changed, 51 insertions(+), 13 deletions(-)

diff --git a/src/server_server.rs b/src/server_server.rs
index c4478d3..144ea0a 100644
--- a/src/server_server.rs
+++ b/src/server_server.rs
@@ -387,13 +387,25 @@ pub async fn get_public_rooms_route(
     .into())
 }
 
-#[derive(Debug, Ord, PartialOrd, Eq, PartialEq)]
-pub enum PrevEvents<T> {
+#[derive(Clone, Debug, Ord, PartialOrd, Eq, PartialEq)]
+pub enum AuthEvents<T> {
     Sequential(T),
     Fork(Vec<T>),
 }
 
-impl<T: Clone> PrevEvents<T> {
+impl<T> IntoIterator for AuthEvents<T> {
+    type Item = T;
+    type IntoIter = std::vec::IntoIter<Self::Item>;
+
+    fn into_iter(self) -> Self::IntoIter {
+        match self {
+            Self::Sequential(item) => vec![item].into_iter(),
+            Self::Fork(list) => list.into_iter(),
+        }
+    }
+}
+
+impl<T: Clone> AuthEvents<T> {
     pub fn new(id: &[T]) -> Self {
         match id {
             [] => panic!("All events must have previous event"),
@@ -490,15 +502,15 @@ pub async fn send_transaction_message_route<'a>(
         let mut missing = vec![];
         let mut seen = state_res::StateMap::new();
 
-        let mut prev_ids = vec![PrevEvents::new(&pdu.prev_events)];
+        let mut prev_ids = vec![AuthEvents::new(&pdu.prev_events)];
 
         // This is `while let Some(event_id) = prev_ids.pop_front()` but with a fancy continue
         // in the case of a failed request to the server that sent the event
         'inner: loop {
-            // TODO: if this is ever more that 1 at a time we must do actual
+            // TODO: if this is ever more than 1 at a time we must do actual
             // full state resolution not just auth
             match prev_ids.pop() {
-                Some(PrevEvents::Sequential(id)) => match db
+                Some(AuthEvents::Sequential(id)) => match db
                     .rooms
                     .pdu_state_hash(&db.rooms.get_pdu_id(&id)?.unwrap_or_default())?
                 {
@@ -528,8 +540,8 @@ pub async fn send_transaction_message_route<'a>(
                                 // TODO: do we need this
                                 assert_eq!(room_id, &prev_pdu.room_id);
 
-                                prev_ids.push(PrevEvents::new(&prev_pdu.prev_events));
-                                missing.push(PrevEvents::Sequential(prev_pdu));
+                                prev_ids.push(AuthEvents::new(&prev_pdu.prev_events));
+                                missing.push(AuthEvents::Sequential(prev_pdu));
                             }
                             // We can't hard fail because there are some valid errors, just
                             // keep checking PDU's
@@ -544,7 +556,7 @@ pub async fn send_transaction_message_route<'a>(
                         };
                     }
                 },
-                Some(PrevEvents::Fork(ids)) => {
+                Some(AuthEvents::Fork(ids)) => {
                     error!(
                         "prev_events > 1: {}",
                         serde_json::to_string_pretty(&pdu).unwrap()
@@ -609,10 +621,10 @@ pub async fn send_transaction_message_route<'a>(
                             },
                         }
                     }
-                    prev_ids.push(PrevEvents::new(
+                    prev_ids.push(AuthEvents::new(
                         &prev_fork_ids.into_iter().collect::<Vec<_>>(),
                     ));
-                    missing.push(PrevEvents::new(&missing_fork));
+                    missing.push(AuthEvents::new(&missing_fork));
                 }
                 // All done finding missing events
                 None => {
@@ -630,6 +642,32 @@ pub async fn send_transaction_message_route<'a>(
             .iter()
             .map(|(_, v)| (v.event_id.clone(), v.convert_for_state_res()))
             .collect::<BTreeMap<_, Arc<state_res::StateEvent>>>();
+
+        if !missing.is_empty() {
+            // This is the state at incoming pdu
+            state_snapshot = match state_res::StateResolution::resolve_incoming(
+                room_id,
+                &RoomVersionId::Version6,
+                &state_snapshot,
+                missing
+                    .iter()
+                    .cloned()
+                    .flatten()
+                    .filter(|pdu| pdu.state_key.is_some()) // remove non state events
+                    .map(|pdu| ((pdu.kind, pdu.state_key.unwrap()), pdu.event_id))
+                    .collect(),
+                Some(accum_event_map),
+                &db.rooms,
+            ) {
+                Ok(res) => res,
+                Err(err) => {
+                    resolved_map.insert(event_id, Err(err.to_string()));
+                    error!("{}", err);
+                    continue;
+                }
+            }
+        }
+
         // TODO: this only accounts for sequentially missing events no holes will be filled
         // and I'm still not sure what happens when a fork introduces multiple `prev_events`
         //
@@ -637,7 +675,7 @@ pub async fn send_transaction_message_route<'a>(
         // prev_event of the incoming event so we reverse the order oldest -> most recent
         for missing_pdu in missing.into_iter().rev() {
             match missing_pdu {
-                PrevEvents::Sequential(missing_pdu) => {
+                AuthEvents::Sequential(missing_pdu) => {
                     // For state events
                     if missing_pdu.state_key.is_some() {
                         let missing_pdu = missing_pdu.convert_for_state_res();
@@ -751,7 +789,7 @@ pub async fn send_transaction_message_route<'a>(
                         // Continue this inner for loop adding all the missing events
                     }
                 }
-                PrevEvents::Fork(pdus) => {
+                AuthEvents::Fork(pdus) => {
                     for missing_pdu in pdus.into_iter().rev() {
                         // For state events
                         if missing_pdu.state_key.is_some() {