Various sliding sync tweaks (#446)

* Refactor SS configuration and add (unfinished) support for adding views dynamically.

* Implement pop and clear support on the room summary provider

* Register views against sliding sync

* Read invalidated vislbeRoomsSummaryProvider from the allRoomSummaryProvider

* Switch SS window range setting from the ScrollViewAdapter to a publisher debounce

* Tweak allRoomsView addition: switch from listening the visibleRoomsView's state to when it publishes the first diff update

* Cleanup client delegate and sliding sync observers and lifecycle

* Bump the RustSDK to 1.0.30-alpha

* Reuse startSync within restartSync

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

@@ -46,7 +46,7 @@ class MockRoomSummaryProvider: RoomSummaryProviderProtocol {
     
     func updateRoomsWithIdentifiers(_ identifiers: [String]) { }
     
-    func updateVisibleRange(_ range: ClosedRange<Int>) { }
+    func updateVisibleRange(_ range: Range<Int>) { }
     
     // MARK: - Private
     

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

@@ -68,7 +68,7 @@ class RoomSummaryProvider: RoomSummaryProviderProtocol {
         }
     }
     
-    func updateVisibleRange(_ range: ClosedRange<Int>) {
+    func updateVisibleRange(_ range: Range<Int>) {
         slidingSyncViewProxy.updateVisibleRange(range)
     }
     
@@ -181,6 +181,7 @@ class RoomSummaryProvider: RoomSummaryProviderProtocol {
         }
     }
     
+    // swiftlint:disable:next cyclomatic_complexity
     private func buildDiff(from diff: SlidingSyncViewRoomsListDiff, on rooms: [RoomSummary]) -> CollectionDifference<RoomSummary>? {
         var changes = [CollectionDifference<RoomSummary>.Change]()
         
@@ -216,6 +217,18 @@ class RoomSummaryProvider: RoomSummaryProviderProtocol {
             for (index, value) in values.enumerated() {
                 changes.append(.insert(offset: index, element: buildSummaryForRoomListEntry(value), associatedWith: nil))
             }
+        case .clear:
+            MXLog.verbose("Clear all items, current total count: \(rooms.count)")
+            for (index, value) in rooms.enumerated() {
+                changes.append(.remove(offset: index, element: value, associatedWith: nil))
+            }
+        case .pop:
+            MXLog.verbose("Pop, current total count: \(rooms.count)")
+            guard let value = rooms.last else {
+                fatalError()
+            }
+            
+            changes.append(.remove(offset: rooms.count - 1, element: value, associatedWith: nil))
         }
         
         return CollectionDifference(changes)

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

@@ -55,5 +55,5 @@ protocol RoomSummaryProviderProtocol {
     /// - Parameter identifiers: the identifiers for the rooms that have changed
     func updateRoomsWithIdentifiers(_ identifiers: [String])
     
-    func updateVisibleRange(_ range: ClosedRange<Int>)
+    func updateVisibleRange(_ range: Range<Int>)
 }