Handle threaded pinned events (#4704)

* implemented focussing a threaded event through the banner tap

* view in timeline implementation for threaded events

* added a test and improved the existing one

* pr suggestions

* put the logic for fetching the event in the view models

ElementX/Sources/Screens/Timeline/TimelineModels.swift

@@ -28,7 +28,7 @@ enum TimelineViewModelAction {
     case displayThread(itemID: TimelineItemIdentifier)
     case composer(action: TimelineComposerAction)
     case hasScrolled(direction: ScrollDirection)
-    case viewInRoomTimeline(eventID: String)
+    case viewInRoomTimeline(eventID: String, threadRootEventID: String?)
     case displayRoom(roomID: String, via: [String])
     case displayMediaDetails(item: EventBasedMessageTimelineItemProtocol)
 }

ElementX/Sources/Screens/Timeline/TimelineViewModel.swift

@@ -495,7 +495,7 @@ class TimelineViewModel: TimelineViewModelType, TimelineViewModelProtocol {
                 case .showDebugInfo(let debugInfo):
                     state.bindings.debugInfo = debugInfo
                 case .viewInRoomTimeline(let eventID):
-                    actionsSubject.send(.viewInRoomTimeline(eventID: eventID))
+                    Task { await self.viewInRoomTimeline(eventID: eventID) }
                 case .displayThread(let itemID):
                     actionsSubject.send(.displayThread(itemID: itemID))
                 }
@@ -503,6 +503,20 @@ class TimelineViewModel: TimelineViewModelType, TimelineViewModelProtocol {
             .store(in: &cancellables)
     }
     
+    func viewInRoomTimeline(eventID: String) async {
+        switch await roomProxy.loadOrFetchEventDetails(for: eventID) {
+        case .success(let event):
+            let threadRootEventID: String? = if appSettings.threadsEnabled {
+                event.threadRootEventId()
+            } else {
+                nil
+            }
+            actionsSubject.send(.viewInRoomTimeline(eventID: eventID, threadRootEventID: threadRootEventID))
+        case .failure:
+            userIndicatorController.submitIndicator(.init(title: L10n.errorUnknown))
+        }
+    }
+    
     private func setupAppSettingsSubscriptions() {
         appSettings.$sharePresence
             .weakAssign(to: \.state.showReadReceipts, on: self)