Notifications marker

ServiceLayer/Sources/ServiceLayer/Services/CollectionService.swift

@@ -14,6 +14,8 @@ public protocol CollectionService {
     var navigationService: NavigationService { get }
     var positionTimeline: Timeline? { get }
     func request(maxId: String?, minId: String?, search: Search?) -> AnyPublisher<Never, Error>
+    func requestMarkerLastReadId() -> AnyPublisher<CollectionItem.Id, Error>
+    func setMarkerLastReadId(_ id: CollectionItem.Id) -> AnyPublisher<CollectionItem.Id, Error>
 }
 
 extension CollectionService {
@@ -30,4 +32,10 @@ extension CollectionService {
     public var titleLocalizationComponents: AnyPublisher<[String], Never> { Empty().eraseToAnyPublisher() }
 
     public var positionTimeline: Timeline? { nil }
+
+    public func requestMarkerLastReadId() -> AnyPublisher<CollectionItem.Id, Error> { Empty().eraseToAnyPublisher() }
+
+    public func setMarkerLastReadId(_ id: CollectionItem.Id) -> AnyPublisher<CollectionItem.Id, Error> {
+        Empty().eraseToAnyPublisher()
+    }
 }

ServiceLayer/Sources/ServiceLayer/Services/IdentityService.swift

@@ -119,12 +119,6 @@ public extension IdentityService {
             .eraseToAnyPublisher()
     }
 
-    func getMarker(_ markerTimeline: Marker.Timeline) -> AnyPublisher<Marker, Error> {
-        mastodonAPIClient.request(MarkersEndpoint.get([markerTimeline]))
-            .compactMap { $0[markerTimeline.rawValue] }
-            .eraseToAnyPublisher()
-    }
-
     func getLocalLastReadId(timeline: Timeline) -> String? {
         contentDatabase.lastReadId(timelineId: timeline.id)
     }

ServiceLayer/Sources/ServiceLayer/Services/NotificationsService.swift

@@ -55,4 +55,16 @@ extension NotificationsService: CollectionService {
             .flatMap { contentDatabase.insert(notifications: $0.result) }
             .eraseToAnyPublisher()
     }
+
+    public func requestMarkerLastReadId() -> AnyPublisher<CollectionItem.Id, Error> {
+        mastodonAPIClient.request(MarkersEndpoint.get([.notifications]))
+            .compactMap { $0.values.first?.lastReadId }
+            .eraseToAnyPublisher()
+    }
+
+    public func setMarkerLastReadId(_ id: CollectionItem.Id) -> AnyPublisher<CollectionItem.Id, Error> {
+        mastodonAPIClient.request(MarkersEndpoint.post([.notifications: id]))
+            .compactMap { $0.values.first?.lastReadId }
+            .eraseToAnyPublisher()
+    }
 }

ViewModels/Sources/ViewModels/View Models/CollectionItemsViewModel.swift

@@ -21,10 +21,11 @@ public class CollectionItemsViewModel: ObservableObject {
     private var topVisibleIndexPath = IndexPath(item: 0, section: 0)
     private let lastReadId = CurrentValueSubject<String?, Never>(nil)
     private var lastSelectedLoadMore: LoadMore?
-    private var hasRequestedUsingMarker = false
+    private var localLastReadId: CollectionItem.Id?
-    private var markerScrollPositionItemId: CollectionItem.Id?
+    private var markerLastReadId: CollectionItem.Id?
     private var cancellables = Set<AnyCancellable>()
 
+    // swiftlint:disable:next function_body_length
     public init(collectionService: CollectionService, identityContext: IdentityContext) {
         self.collectionService = collectionService
         self.identityContext = identityContext
@@ -50,18 +51,32 @@ public class CollectionItemsViewModel: ObservableObject {
             .sink { _ in }
             .store(in: &cancellables)
 
+        let debouncedLastReadId = lastReadId
+            .compactMap { $0 }
+            .removeDuplicates()
+            .debounce(for: .seconds(Self.lastReadIdDebounceInterval), scheduler: DispatchQueue.global())
+            .share()
+
+        debouncedLastReadId
+            .filter { [weak self] in
+                guard let markerLastReadId = self?.markerLastReadId else { return false }
+
+                return $0 > markerLastReadId
+            }
+            .flatMap { collectionService.setMarkerLastReadId($0) }
+            .receive(on: DispatchQueue.main)
+            .sink { _ in } receiveValue: { [weak self] in self?.markerLastReadId = $0 }
+            .store(in: &cancellables)
+
         if let timeline = collectionService.positionTimeline {
             if identityContext.appPreferences.positionBehavior(timeline: timeline) == .localRememberPosition {
-                markerScrollPositionItemId = identityContext.service.getLocalLastReadId(timeline: timeline)
+                localLastReadId = identityContext.service.getLocalLastReadId(timeline: timeline)
             }
 
-            lastReadId
+            debouncedLastReadId
                 .filter { _ in
                     identityContext.appPreferences.positionBehavior(timeline: timeline) == .localRememberPosition
                 }
-                .compactMap { $0 }
-                .removeDuplicates()
-                .debounce(for: .seconds(Self.lastReadIdDebounceInterval), scheduler: DispatchQueue.global())
                 .flatMap { identityContext.service.setLocalLastReadId($0, timeline: timeline) }
                 .sink { _ in } receiveValue: { _ in }
                 .store(in: &cancellables)
@@ -119,6 +134,10 @@ extension CollectionItemsViewModel: CollectionViewModel {
                 receiveCompletion: { [weak self] _ in self?.loadingSubject.send(false) })
             .sink { _ in }
             .store(in: &cancellables)
+        collectionService.requestMarkerLastReadId()
+            .sink { _ in } receiveValue: { [weak self] in self?.markerLastReadId = $0 }
+            .store(in: &cancellables)
+
     }
 
     public func select(indexPath: IndexPath) {
@@ -375,9 +394,9 @@ private extension CollectionItemsViewModel {
         let items = lastUpdate.sections.map(\.items).reduce([], +)
         let newItems = newSections.map(\.items).reduce([], +)
 
-        if let itemId = markerScrollPositionItemId,
+        if let itemId = localLastReadId,
            newItems.contains(where: { $0.itemId == itemId }) {
-            markerScrollPositionItemId = nil
+            localLastReadId = nil
 
             return itemId
         }