Don't run into an endless loop if no followers exist

See also 3fc2793

Mastodon/Scene/Profile/Follower/FollowerListViewController.swift

@@ -50,7 +50,7 @@ final class FollowerListViewController: UIViewController, NeedsDependency {
         view.addSubview(tableView)
         tableView.pinToParent()
         tableView.delegate = self
-        tableView.refreshControl?.addTarget(self, action: #selector(FollowingListViewController.refresh(_:)), for: .valueChanged)
+        tableView.refreshControl?.addTarget(self, action: #selector(FollowerListViewController.refresh(_:)), for: .valueChanged)
 
         viewModel.tableView = tableView
 
@@ -65,23 +65,13 @@ extension FollowerListViewController {
     override func viewDidLoad() {
         super.viewDidLoad()
         
-        title = L10n.Scene.Follower.title
-        
-        view.backgroundColor = .secondarySystemBackground
-        
-        tableView.translatesAutoresizingMaskIntoConstraints = false
-        view.addSubview(tableView)
-        tableView.pinToParent()
-        
-        tableView.delegate = self
         viewModel.setupDiffableDataSource(
             tableView: tableView,
             userTableViewCellDelegate: self
         )
         
         // setup batch fetch
-        viewModel.listBatchFetchViewModel.setup(scrollView: tableView)
-        viewModel.listBatchFetchViewModel.shouldFetch
+        viewModel.shouldFetch
             .receive(on: DispatchQueue.main)
             .sink { [weak self] _ in
                 guard let self = self else { return }
@@ -100,6 +90,8 @@ extension FollowerListViewController {
             self.viewModel.stateMachine.enter(FollowerListViewModel.State.Reloading.self)
         }
         .store(in: &disposeBag)
+
+        tableView.refreshControl = UIRefreshControl()
     }
     
     override func viewWillAppear(_ animated: Bool) {
@@ -166,3 +158,24 @@ extension FollowerListViewController: DataSourceProvider {
         return tableView.indexPath(for: cell)
     }
 }
+
+//MARK: - UIScrollViewDelegate
+
+extension FollowerListViewController: UIScrollViewDelegate {
+    func scrollViewDidScroll(_ scrollView: UIScrollView) {
+
+        if scrollView.isDragging || scrollView.isTracking { return }
+
+        let frame = scrollView.frame
+        let contentOffset = scrollView.contentOffset
+        let contentSize = scrollView.contentSize
+
+        let visibleBottomY = contentOffset.y + frame.height
+        let offset = 2 * frame.height
+        let fetchThrottleOffsetY = contentSize.height - offset
+
+        if visibleBottomY > fetchThrottleOffsetY {
+            viewModel.shouldFetch.send()
+        }
+    }
+}

Mastodon/Scene/Profile/Follower/FollowerListViewModel+State.swift

@@ -144,6 +144,14 @@ extension FollowerListViewModel.State {
                         authenticationBox: viewModel.authContext.mastodonAuthenticationBox
                     )
 
+                    if accountResponse.value.isEmpty {
+                        await enter(state: NoMore.self)
+
+                        viewModel.accounts = []
+                        viewModel.relationships = []
+                        return
+                    }
+
                     var hasNewAppend = false
 
                     let newRelationships = try await viewModel.context.apiService.relationship(forAccounts: accountResponse.value, authenticationBox: viewModel.authContext.mastodonAuthenticationBox)

Mastodon/Scene/Profile/Follower/FollowerListViewModel.swift

@@ -22,11 +22,11 @@ final class FollowerListViewModel {
     @Published var accounts: [Mastodon.Entity.Account]
     @Published var relationships: [Mastodon.Entity.Relationship]
     
-    let listBatchFetchViewModel: ListBatchFetchViewModel
-    
     @Published var domain: String?
     @Published var userID: String?
-    
+
+    let shouldFetch = PassthroughSubject<Void, Never>()
+
     var tableView: UITableView?
     
     // output
@@ -56,6 +56,5 @@ final class FollowerListViewModel {
         self.userID = userID
         self.accounts = []
         self.relationships = []
-        self.listBatchFetchViewModel = ListBatchFetchViewModel()
     }
 }

Mastodon/Scene/Profile/Following/FollowingListViewController.swift

@@ -173,7 +173,6 @@ extension FollowingListViewController: UIScrollViewDelegate {
         if visibleBottomY > fetchThrottleOffsetY {
             viewModel.shouldFetch.send()
         }
-
     }
 }