Initial commit

src/conversation/matrix/room_event_fetcher.rs

@@ -0,0 +1,46 @@
+use mxlink::matrix_sdk::deserialized_responses::TimelineEvent;
+use mxlink::matrix_sdk::ruma::OwnedEventId;
+use mxlink::matrix_sdk::Room;
+
+use quick_cache::sync::Cache;
+
+pub struct RoomEventFetcher {
+    lru_cache: Option<Cache<OwnedEventId, TimelineEvent>>,
+}
+
+impl RoomEventFetcher {
+    pub fn new(lru_cache_size: Option<usize>) -> Self {
+        let lru_cache = lru_cache_size.map(Cache::new);
+
+        Self { lru_cache }
+    }
+
+    #[tracing::instrument(skip(self), fields(room_id = room.room_id().as_str(), event_id = event_id.as_str()))]
+    pub async fn fetch_event_in_room(
+        &self,
+        event_id: &OwnedEventId,
+        room: &Room,
+    ) -> mxlink::matrix_sdk::Result<TimelineEvent> {
+        let Some(lru_cache) = &self.lru_cache else {
+            return room.event(event_id).await;
+        };
+
+        let guard = lru_cache.get_value_or_guard_async(event_id).await;
+
+        match guard {
+            Ok(config) => {
+                tracing::trace!("Returning existing cached event..");
+                return Ok(config);
+            }
+            Err(guard) => {
+                let event = room.event(event_id).await?;
+
+                let _ = guard.insert(event.clone());
+
+                tracing::trace!("Returning now-cached event");
+
+                return Ok(event);
+            }
+        }
+    }
+}