Add the empty state to SpaceScreen. (#4985)

* Rename PaginationState.timelineEndReached to PaginationState.endReached.

* Rename PaginationState to TimelinePaginationState.

Also renames PaginationStatus to PaginationState so that a TimelinePaginationState consists of the forward and backward pagination states.

* Add the empty state to SpaceScreen.

Only has 1 of the 2 buttons for now.

ElementX/Sources/Services/Timeline/TimelineController/MockTimelineController.swift

@@ -26,7 +26,7 @@ class MockTimelineController: TimelineControllerProtocol {
     
     let callbacks = PassthroughSubject<TimelineControllerCallback, Never>()
     
-    var paginationState: PaginationState = .initial {
+    var paginationState: TimelinePaginationState = .initial {
         didSet {
             callbacks.send(.paginationState(paginationState))
         }
@@ -45,7 +45,7 @@ class MockTimelineController: TimelineControllerProtocol {
     
     static var emptyMediaGallery: MockTimelineController {
         let mock = MockTimelineController(timelineKind: .media(.mediaFilesScreen))
-        mock.paginationState = PaginationState(backward: .timelineEndReached, forward: .timelineEndReached)
+        mock.paginationState = TimelinePaginationState(backward: .endReached, forward: .endReached)
         return mock
     }
     
@@ -86,7 +86,7 @@ class MockTimelineController: TimelineControllerProtocol {
     func paginateBackwards(requestSize: UInt16) async -> Result<Void, TimelineControllerError> {
         paginateBackwardsCallCount += 1
         
-        paginationState = PaginationState(backward: .paginating, forward: .timelineEndReached)
+        paginationState = TimelinePaginationState(backward: .paginating, forward: .endReached)
         
         if client == nil {
             try? await simulateBackPagination()
@@ -331,8 +331,8 @@ class MockTimelineController: TimelineControllerProtocol {
     /// Prepends the next chunk of items to the `timelineItems` array.
     private func simulateBackPagination() async throws {
         defer {
-            paginationState = PaginationState(backward: backPaginationResponses.isEmpty ? .timelineEndReached : .idle,
-                                              forward: .timelineEndReached)
+            paginationState = TimelinePaginationState(backward: backPaginationResponses.isEmpty ? .endReached : .idle,
+                                                      forward: .endReached)
         }
         
         guard !backPaginationResponses.isEmpty else { return }

ElementX/Sources/Services/Timeline/TimelineController/TimelineController.swift

@@ -30,7 +30,7 @@ class TimelineController: TimelineControllerProtocol {
     
     private(set) var timelineItems = [RoomTimelineItemProtocol]()
     
-    private(set) var paginationState: PaginationState = .initial {
+    private(set) var paginationState: TimelinePaginationState = .initial {
         didSet {
             callbacks.send(.paginationState(paginationState))
         }
@@ -65,7 +65,7 @@ class TimelineController: TimelineControllerProtocol {
         }
         
         Task {
-            paginationState = PaginationState(backward: .paginating, forward: .paginating)
+            paginationState = TimelinePaginationState(backward: .paginating, forward: .paginating)
             
             switch await focusOnEvent(initialFocussedEventID, timelineSize: 100) {
             case .success:
@@ -396,7 +396,7 @@ class TimelineController: TimelineControllerProtocol {
         isSwitchingTimelines = true
         
         // Inform the world that the initial items are loading from the store
-        paginationState = PaginationState(backward: .paginating, forward: .paginating)
+        paginationState = TimelinePaginationState(backward: .paginating, forward: .paginating)
         callbacks.send(.isLive(activeTimelineItemProvider.kind == .live))
         
         updateTimelineItemsCancellable = Task { [weak self, activeTimelineItemProvider] in
@@ -411,7 +411,7 @@ class TimelineController: TimelineControllerProtocol {
         }.asCancellable()
     }
     
-    private func updateTimelineItems(itemProxies: [TimelineItemProxy], paginationState: PaginationState) async {
+    private func updateTimelineItems(itemProxies: [TimelineItemProxy], paginationState: TimelinePaginationState) async {
         let isNewTimeline = isSwitchingTimelines
         isSwitchingTimelines = false
         
@@ -462,14 +462,14 @@ class TimelineController: TimelineControllerProtocol {
         switch paginationState.backward {
         case .paginating:
             newTimelineItems.insert(PaginationIndicatorRoomTimelineItem(position: .start), at: 0)
-        case .idle, .timelineEndReached:
+        case .idle, .endReached:
             break
         }
         
         switch paginationState.forward {
         case .paginating:
             newTimelineItems.insert(PaginationIndicatorRoomTimelineItem(position: .end), at: newTimelineItems.count)
-        case .idle, .timelineEndReached:
+        case .idle, .endReached:
             break
         }
         

ElementX/Sources/Services/Timeline/TimelineController/TimelineControllerProtocol.swift

@@ -12,7 +12,7 @@ import SwiftUI
 
 enum TimelineControllerCallback {
     case updatedTimelineItems(timelineItems: [RoomTimelineItemProtocol], isSwitchingTimelines: Bool)
-    case paginationState(PaginationState)
+    case paginationState(TimelinePaginationState)
     case isLive(Bool)
 }
 
@@ -49,7 +49,7 @@ protocol TimelineControllerProtocol {
     var timelineItems: [RoomTimelineItemProtocol] { get }
     
     /// The current pagination state, use only for setting up the intial state
-    var paginationState: PaginationState { get }
+    var paginationState: TimelinePaginationState { get }
     
     var callbacks: PassthroughSubject<TimelineControllerCallback, Never> { get }