 }
 
 class MessagesPresenter: MessagesSceneDelegate {
+    
+    // MARK: Properties
 
     private let scene: MessagesScene
     private let privateMessagesService: PrivateMessagesService

    private let showMessageAction: ShowMessageAction
    private let delegate: MessagesPresenterDelegate
    private var presentedMessages = [Message]()

    init(scene: MessagesScene,
         authService: AuthService,

        scene.delegate = self
        authService.determineAuthState(completionHandler: authStateResolved)
    }
    
    // MARK: MessagesSceneDelegate

    func messagesSceneDidSelectMessage(at indexPath: IndexPath) {
        let message = presentedMessages[indexPath[1]]
        showMessageAction.show(message: message)
    }
    
    // MARK: Private

    private func authStateResolved(_ state: AuthState) {
        switch state {
