pr suggestions

ElementX/Sources/Other/SwiftUI/Views/HorizontalHighlightGradient.swift

@@ -8,7 +8,7 @@
 import Compound
 import SwiftUI
 
-struct Highlight: ViewModifier {
+struct HorizontalHighlightGradient: ViewModifier {
     let borderColor: Color
     let primaryColor: Color
     let secondaryColor: Color
@@ -30,6 +30,6 @@ struct Highlight: ViewModifier {
 
 extension View {
     func highlight(borderColor: Color, primaryColor: Color, secondaryColor: Color) -> some View {
-        modifier(Highlight(borderColor: borderColor, primaryColor: primaryColor, secondaryColor: secondaryColor))
+        modifier(HorizontalHighlightGradient(borderColor: borderColor, primaryColor: primaryColor, secondaryColor: secondaryColor))
     }
 }

ElementX/Sources/Screens/HomeScreen/HomeScreenModels.swift

@@ -199,6 +199,14 @@ struct HomeScreenRoom: Identifiable, Equatable {
     
     let isTombstoned: Bool
     
+    var displayedLastMessage: AttributedString? {
+        // If the room is tombstoned, show a specific message, regardless of any last message.
+        guard !isTombstoned else {
+            return AttributedString(L10n.screenRoomlistTombstonedRoomDescription)
+        }
+        return lastMessage
+    }
+    
     static func placeholder() -> HomeScreenRoom {
         HomeScreenRoom(id: UUID().uuidString,
                        roomID: nil,

ElementX/Sources/Screens/HomeScreen/View/HomeScreenRoomCell.swift

@@ -135,12 +135,8 @@ struct HomeScreenRoomCell: View {
     
     @ViewBuilder
     private var lastMessage: some View {
-        // If the room is tombstoned, show a specific message, regardless of any last message.
-        if room.isTombstoned {
-            Text(L10n.screenRoomlistTombstonedRoomDescription)
-                .lastMessageFormatting()
-        } else if let lastMessage = room.lastMessage {
-            Text(lastMessage)
+        if let displayedLastMessage = room.displayedLastMessage {
+            Text(displayedLastMessage)
                 .lastMessageFormatting()
         }
     }

ElementX/Sources/Screens/RoomScreen/RoomScreenViewModel.swift

@@ -331,6 +331,7 @@ class RoomScreenViewModel: RoomScreenViewModelType, RoomScreenViewModelProtocol
     
     private func handleRoomInfoUpdate(_ roomInfo: RoomInfoProxy) async {
         state.hasSuccessor = roomInfo.successor != nil
+        
         let pinnedEventIDs = roomInfo.pinnedEventIDs
         // Only update the loading state of the banner
         if state.pinnedEventsBannerState.isLoading {

ElementX/Sources/Screens/Timeline/TimelineModels.swift

@@ -79,7 +79,7 @@ enum TimelineViewAction {
     case hasScrolled(direction: ScrollDirection)
     case setOpenURLAction(OpenURLAction)
     
-    case seePredecessorTapped
+    case displayPredecessorRoom
 }
 
 enum TimelineComposerAction {

ElementX/Sources/Screens/Timeline/TimelineViewModel.swift

@@ -212,8 +212,10 @@ class TimelineViewModel: TimelineViewModelType, TimelineViewModelProtocol {
             actionsSubject.send(.hasScrolled(direction: direction))
         case .setOpenURLAction(let action):
             state.openURL = action
-        case .seePredecessorTapped:
-            guard let predecessorID = roomProxy.predecessorRoom?.roomId else { return }
+        case .displayPredecessorRoom:
+            guard let predecessorID = roomProxy.predecessorRoom?.roomId else {
+                fatalError("Predecessor room should exist if this action is triggered.")
+            }
             actionsSubject.send(.displayRoom(roomID: predecessorID))
         }
     }

ElementX/Sources/Screens/Timeline/View/TimelineItemViews/TimelineStartRoomTimelineView.swift

@@ -15,8 +15,9 @@ struct TimelineStartRoomTimelineView: View {
     var body: some View {
         VStack(spacing: 14) {
             if context?.viewState.hasPredecessor == true {
-                upgrade
+                upgradeDialogue
             }
+            // We don't display the title for tombstoned DMs
             if context?.viewState.isDirectOneToOneRoom != true {
                 Text(title)
                     .font(.compound.bodySM)
@@ -28,13 +29,13 @@ struct TimelineStartRoomTimelineView: View {
         }
     }
     
-    private var upgrade: some View {
+    private var upgradeDialogue: some View {
         VStack(spacing: 16) {
             Text(L10n.screenRoomTimelineUpgradedRoomMessage)
                 .font(.compound.bodyMD)
                 .foregroundColor(.compound.textPrimary)
             Button {
-                context?.send(viewAction: .seePredecessorTapped)
+                context?.send(viewAction: .displayPredecessorRoom)
             } label: {
                 Text(L10n.screenRoomTimelineUpgradedRoomAction)
                     .frame(maxWidth: .infinity)

ElementX/Sources/Services/Room/JoinedRoomProxy.swift

@@ -34,7 +34,14 @@ class JoinedRoomProxy: JoinedRoomProxyProtocol {
     
     var ownUserID: String { room.ownUserId() }
     
-    lazy var predecessorRoom: PredecessorRoom? = room.predecessorRoom()
+    // The predecessor is set on room creation and never changes, so we lazily store it.
+    lazy var predecessorRoom = room.predecessorRoom()
+    
+    // The successor may change over time, so we access it dynamically.
+    // It's suggested to observe it through the `infoPublisher`
+    var successorRoom: SuccessorRoom? {
+        room.successorRoom()
+    }
     
     let timeline: TimelineProxyProtocol
     

ElementX/Sources/Services/Room/RoomProxyProtocol.swift

@@ -78,6 +78,8 @@ protocol JoinedRoomProxyProtocol: RoomProxyProtocol {
     
     var predecessorRoom: PredecessorRoom? { get }
     
+    var successorRoom: SuccessorRoom? { get }
+    
     func subscribeForUpdates() async
     
     func subscribeToRoomInfoUpdates()

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

@@ -55,7 +55,6 @@ struct RoomSummary {
     
     let isMarkedUnread: Bool
     let isFavourite: Bool
-    
     let isTombstoned: Bool
     
     var hasUnreadMessages: Bool { unreadMessagesCount > 0 }

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

@@ -480,11 +480,12 @@ class TimelineController: TimelineControllerProtocol {
             case .readMarker:
                 return ReadMarkerRoomTimelineItem(id: .virtual(uniqueID: uniqueID))
             case .timelineStart:
-                if hasPredecessor {
+                // We always display the timeline start item, if there is a predecessor room.
+                guard !hasPredecessor else {
                     return TimelineStartRoomTimelineItem(name: roomDisplayName)
-                } else {
-                    return isDM ? nil : TimelineStartRoomTimelineItem(name: roomDisplayName)
                 }
+                // If not we only display the timeline start item if this is not a DM.
+                return isDM ? nil : TimelineStartRoomTimelineItem(name: roomDisplayName)
             }
         case .unknown:
             return nil

ElementX/Sources/Services/Timeline/TimelineItems/Items/Virtual/TimelineStartRoomTimelineItem.swift

@@ -8,6 +8,7 @@
 import Foundation
 
 struct TimelineStartRoomTimelineItem: DecorationTimelineItemProtocol, Equatable {
+    // Using a static identifier makes the animations consistent in SwiftUI
     let id: TimelineItemIdentifier = .virtual(uniqueID: .init("TimelineStart"))
     let name: String?
 }