From 9386b500a8ff70f401efc51319d5ab8ce852e970 Mon Sep 17 00:00:00 2001
From: Devin R <devin.ragotzy@gmail.com>
Date: Wed, 29 Apr 2020 19:28:58 -0400
Subject: [PATCH] message: keep MessageQueue sorted by origin_server_ts

---
 matrix_sdk/src/models/message.rs | 130 ++++++++++++++++++++-----------
 1 file changed, 86 insertions(+), 44 deletions(-)

diff --git a/matrix_sdk/src/models/message.rs b/matrix_sdk/src/models/message.rs
index 6cb2482f..f867a4cc 100644
--- a/matrix_sdk/src/models/message.rs
+++ b/matrix_sdk/src/models/message.rs
@@ -1,43 +1,52 @@
-use std::collections::{vec_deque::IntoIter, VecDeque};
+use std::cmp::Ordering;
+use std::ops::Deref;
+use std::vec::IntoIter;
 
 use crate::events::collections::all::RoomEvent;
 use crate::events::room::message::MessageEvent;
 use crate::events::EventJson;
 
-use serde::{de, ser};
-
-pub(crate) mod ser_deser {
-    use super::*;
-
-    pub fn deserialize<'de, D>(deserializer: D) -> Result<MessageQueue, D::Error>
-    where
-        D: de::Deserializer<'de>,
-    {
-        let messages: VecDeque<EventJson<RoomEvent>> = de::Deserialize::deserialize(deserializer)?;
-
-        // TODO this should probably bail out if deserialization fails not skip
-        let msgs: VecDeque<RoomEvent> = messages
-            .into_iter()
-            .flat_map(|json| json.deserialize())
-            .collect();
-
-        Ok(MessageQueue { msgs })
-    }
-
-    pub fn serialize<S>(msgs: &MessageQueue, serializer: S) -> Result<S::Ok, S::Error>
-    where
-        S: ser::Serializer,
-    {
-        use ser::Serialize;
-
-        msgs.msgs.serialize(serializer)
-    }
-}
+use serde::{de, ser, Serialize};
 
 /// A queue that holds at most 10 messages received from the server.
 #[derive(Clone, Debug, Default)]
 pub struct MessageQueue {
-    msgs: VecDeque<RoomEvent>,
+    msgs: Vec<MessageWrapper>,
+}
+
+#[derive(Clone, Debug, Serialize)]
+pub struct MessageWrapper(MessageEvent);
+
+impl Deref for MessageWrapper {
+    type Target = MessageEvent;
+
+    fn deref(&self) -> &Self::Target {
+        &self.0
+    }
+}
+
+impl PartialEq for MessageWrapper {
+    fn eq(&self, other: &MessageWrapper) -> bool {
+        self.0.event_id == other.0.event_id
+            && self.0.room_id == other.0.room_id
+            && self.0.origin_server_ts == other.0.origin_server_ts
+            && self.0.sender == other.0.sender
+            && self.0.content == other.0.content
+    }
+}
+
+impl Eq for MessageWrapper {}
+
+impl PartialOrd for MessageWrapper {
+    fn partial_cmp(&self, other: &MessageWrapper) -> Option<Ordering> {
+        Some(self.0.origin_server_ts.cmp(&other.0.origin_server_ts))
+    }
+}
+
+impl Ord for MessageWrapper {
+    fn cmp(&self, other: &MessageWrapper) -> Ordering {
+        self.partial_cmp(other).unwrap_or(Ordering::Equal)
+    }
 }
 
 impl PartialEq for MessageQueue {
@@ -47,12 +56,7 @@ impl PartialEq for MessageQueue {
                 .msgs
                 .iter()
                 .zip(other.msgs.iter())
-                .all(|(a, b)| match (a, b) {
-                    (RoomEvent::RoomMessage(msg_a), RoomEvent::RoomMessage(msg_b)) => {
-                        msg_a.event_id == msg_b.event_id
-                    }
-                    _ => false,
-                })
+                .all(|(msg_a, msg_b)| msg_a.event_id == msg_b.event_id)
     }
 }
 
@@ -60,28 +64,32 @@ impl MessageQueue {
     /// Create a new empty `MessageQueue`.
     pub fn new() -> Self {
         Self {
-            msgs: VecDeque::with_capacity(20),
+            msgs: Vec::with_capacity(20),
         }
     }
 
-    /// Appends a `MessageEvent` to the end of the `MessageQueue`.
+    /// Inserts a `MessageEvent` into `MessageQueue`, sorted by by `origin_server_ts`.
     ///
     /// Removes the oldest element in the queue if there are more than 10 elements.
     pub fn push(&mut self, msg: MessageEvent) -> bool {
-        self.msgs.push_back(RoomEvent::RoomMessage(msg));
+        let message = MessageWrapper(msg);
+        match self.msgs.binary_search_by(|m| m.cmp(&message)) {
+            Ok(pos) => self.msgs.insert(pos, message),
+            Err(pos) => self.msgs.insert(pos, message),
+        }
         if self.msgs.len() > 10 {
-            self.msgs.pop_front();
+            self.msgs.remove(0);
         }
         true
     }
 
-    pub fn iter(&self) -> impl Iterator<Item = &RoomEvent> {
+    pub fn iter(&self) -> impl Iterator<Item = &MessageWrapper> {
         self.msgs.iter()
     }
 }
 
 impl IntoIterator for MessageQueue {
-    type Item = RoomEvent;
+    type Item = MessageWrapper;
     type IntoIter = IntoIter<Self::Item>;
 
     fn into_iter(self) -> Self::IntoIter {
@@ -89,6 +97,40 @@ impl IntoIterator for MessageQueue {
     }
 }
 
+pub(crate) mod ser_deser {
+    use super::*;
+
+    pub fn deserialize<'de, D>(deserializer: D) -> Result<MessageQueue, D::Error>
+    where
+        D: de::Deserializer<'de>,
+    {
+        let messages: Vec<EventJson<RoomEvent>> = de::Deserialize::deserialize(deserializer)?;
+
+        // TODO this should probably bail out if deserialization fails not skip
+        let msgs: Vec<MessageWrapper> = messages
+            .into_iter()
+            .flat_map(|json| json.deserialize())
+            .flat_map(|ev| {
+                if let RoomEvent::RoomMessage(msg) = ev {
+                    Some(msg)
+                } else {
+                    None
+                }
+            })
+            .map(MessageWrapper)
+            .collect();
+
+        Ok(MessageQueue { msgs })
+    }
+
+    pub fn serialize<S>(msgs: &MessageQueue, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: ser::Serializer,
+    {
+        msgs.msgs.serialize(serializer)
+    }
+}
+
 #[cfg(test)]
 mod test {
     use super::*;
@@ -98,7 +140,7 @@ mod test {
 
     use crate::events::{collections::all::RoomEvent, EventJson};
     use crate::identifiers::{RoomId, UserId};
-    use crate::{state::ClientState, Room};
+    use crate::Room;
 
     #[test]
     fn serialize() {