feat: show received notification status

Mastodon/Scene/MainTab/MainTabBarController.swift

@@ -167,6 +167,16 @@ extension MainTabBarController {
                 notificationViewController.navigationController?.tabBarItem.image = image
             }
             .store(in: &disposeBag)
+        
+        context.notificationService.requestRevealNotificationPublisher
+            .receive(on: DispatchQueue.main)
+            .sink { [weak self] notificationID in
+                guard let self = self else { return }
+                self.coordinator.switchToTabBar(tab: .notification)
+                let threadViewModel = RemoteThreadViewModel(context: self.context, notificationID: notificationID)
+                self.coordinator.present(scene: .thread(viewModel: threadViewModel), from: nil, transition: .show)
+            }
+            .store(in: &disposeBag)
     }
         
 }

Mastodon/Scene/Thread/RemoteThreadViewModel.swift

@@ -47,4 +47,43 @@ final class RemoteThreadViewModel: ThreadViewModel {
         }
         .store(in: &disposeBag)
     }
+    
+    // FIXME: multiple account supports
+    init(context: AppContext, notificationID: Mastodon.Entity.Notification.ID) {
+        super.init(context: context, optionalStatus: nil)
+        
+        guard let activeMastodonAuthenticationBox = context.authenticationService.activeMastodonAuthenticationBox.value else {
+            return
+        }
+        let domain = activeMastodonAuthenticationBox.domain
+        context.apiService.notification(
+            notificationID: notificationID,
+            mastodonAuthenticationBox: activeMastodonAuthenticationBox
+        )
+        .retry(3)
+        .sink { completion in
+            switch completion {
+            case .failure(let error):
+                // TODO: handle error
+                os_log(.info, log: .debug, "%{public}s[%{public}ld], %{public}s: remote notification %s fetch failed: %s", ((#file as NSString).lastPathComponent), #line, #function, notificationID, error.localizedDescription)
+            case .finished:
+                os_log(.info, log: .debug, "%{public}s[%{public}ld], %{public}s: remote notification %s fetched", ((#file as NSString).lastPathComponent), #line, #function, notificationID)
+            }
+        } receiveValue: { [weak self] response in
+            guard let self = self else { return }
+            guard let statusID = response.value.status?.id else { return }
+            
+            let managedObjectContext = context.managedObjectContext
+            let request = Status.sortedFetchRequest
+            request.fetchLimit = 1
+            request.predicate = Status.predicate(domain: domain, id: statusID)
+            guard let status = managedObjectContext.safeFetch(request).first else {
+                assertionFailure()
+                return
+            }
+            self.rootItem.value = .root(statusObjectID: status.objectID, attribute: Item.StatusAttribute())
+        }
+        .store(in: &disposeBag)
+    }
+    
 }

Mastodon/Service/APIService/APIService+Notification.swift

@@ -78,6 +78,34 @@ extension APIService {
             notificationID: notificationID,
             authorization: authorization
         )
+        .flatMap { response -> AnyPublisher<Mastodon.Response.Content<Mastodon.Entity.Notification>, Error> in
+            guard let status = response.value.status else {
+                return Just(response)
+                    .setFailureType(to: Error.self)
+                    .eraseToAnyPublisher()
+            }
+            
+            return APIService.Persist.persistStatus(
+                managedObjectContext: self.backgroundManagedObjectContext,
+                domain: domain,
+                query: nil,
+                response: response.map { _ in [status] },
+                persistType: .lookUp,
+                requestMastodonUserID: nil,
+                log: OSLog.api
+            )
+            .setFailureType(to: Error.self)
+            .tryMap { result -> Mastodon.Response.Content<Mastodon.Entity.Notification> in
+                switch result {
+                case .success:
+                    return response
+                case .failure(let error):
+                    throw error
+                }
+            }
+            .eraseToAnyPublisher()
+        }
+        .eraseToAnyPublisher()
     }
 
 }

Mastodon/Service/NotificationService.swift

@@ -29,6 +29,7 @@ final class NotificationService {
     /// [Token: UserID]
     let notificationSubscriptionDict: [String: NotificationViewModel] = [:]
     let hasUnreadPushNotification = CurrentValueSubject<Bool, Never>(false)
+    let requestRevealNotificationPublisher = PassthroughSubject<Mastodon.Entity.Notification.ID, Never>()
     
     init(
         apiService: APIService,

Mastodon/Supporting Files/AppDelegate.swift

@@ -61,6 +61,8 @@ extension AppDelegate {
 
 // MARK: - UNUserNotificationCenterDelegate
 extension AppDelegate: UNUserNotificationCenterDelegate {
+    
+    // notification present in the foreground
     func userNotificationCenter(
         _ center: UNUserNotificationCenter,
         willPresent notification: UNNotification,
@@ -78,6 +80,7 @@ extension AppDelegate: UNUserNotificationCenterDelegate {
         completionHandler([.sound])
     }
     
+    // response to user action for notification
     func userNotificationCenter(
         _ center: UNUserNotificationCenter,
         didReceive response: UNNotificationResponse,
@@ -93,7 +96,7 @@ extension AppDelegate: UNUserNotificationCenterDelegate {
         let notificationID = String(mastodonPushNotification.notificationID)
         os_log(.info, log: .debug, "%{public}s[%{public}ld], %{public}s: [Push Notification] notification %s", ((#file as NSString).lastPathComponent), #line, #function, notificationID)
         appContext.notificationService.handlePushNotification(notificationID: notificationID)
-        
+        appContext.notificationService.requestRevealNotificationPublisher.send(notificationID)
         completionHandler()
     }
     
@@ -105,6 +108,7 @@ extension AppDelegate: UNUserNotificationCenterDelegate {
         
         return mastodonPushNotification
     }
+    
 }
 
 extension AppContext {