Split incoming large .resets into a reset + append in order to quicker update the UI

ElementX/Sources/Services/Room/RoomSummary/RoomSummaryProvider.swift

@@ -133,19 +133,16 @@ class RoomSummaryProvider: RoomSummaryProviderProtocol {
         
         MXLog.info("\(name): Received \(diffs.count) diffs, current room list \(rooms.compactMap { $0.id ?? "Empty" })")
         
-        rooms = diffs
+        for diff in diffs {
-            .reduce(rooms) { currentItems, diff in
+            // Special case resets in order to prevent large updates from blocking the UI
-                guard let collectionDiff = buildDiff(from: diff, on: currentItems) else {
+            // Render the first resetDiffChunkingThreshhold as a reset and then append the rest to give the UI time to update
-                    MXLog.error("\(name): Failed building CollectionDifference from \(diff)")
+            let resetDiffChunkingThreshhold = 50
-                    return currentItems
+            if case .reset(let values) = diff, values.count > resetDiffChunkingThreshhold {
+                processDiff(RoomListEntriesUpdate.reset(values: Array(values[..<resetDiffChunkingThreshhold])))
+                processDiff(RoomListEntriesUpdate.append(values: Array(values.dropFirst(resetDiffChunkingThreshhold))))
+            } else {
+                processDiff(diff)
             }
-                
-                guard let updatedItems = currentItems.applying(collectionDiff) else {
-                    MXLog.error("\(name): Failed applying diff: \(collectionDiff)")
-                    return currentItems
-                }
-                
-                return updatedItems
         }
         
         detectDuplicatesInRoomList(rooms)
@@ -153,6 +150,20 @@ class RoomSummaryProvider: RoomSummaryProviderProtocol {
         MXLog.info("\(name): Finished applying \(diffs.count) diffs, new room list \(rooms.compactMap { $0.id ?? "Empty" })")
     }
     
+    private func processDiff(_ diff: RoomListEntriesUpdate) {
+        guard let collectionDiff = buildDiff(from: diff, on: rooms) else {
+            MXLog.error("\(name): Failed building CollectionDifference from \(diff)")
+            return
+        }
+        
+        guard let updatedItems = rooms.applying(collectionDiff) else {
+            MXLog.error("\(name): Failed applying diff: \(collectionDiff)")
+            return
+        }
+        
+        rooms = updatedItems
+    }
+
     private func fetchRoomInfo(roomListItem: RoomListItemProtocol) -> RoomInfo? {
         class FetchResult {
             var roomInfo: RoomInfo?