Handle deleted statuses in status action account list

Tusker.xcodeproj/project.pbxproj

@@ -153,6 +153,8 @@
 		D65B4B6229771A3F00DABDFB /* FetchStatusService.swift in Sources */ = {isa = PBXBuildFile; fileRef = D65B4B6129771A3F00DABDFB /* FetchStatusService.swift */; };
 		D65B4B6429771EFF00DABDFB /* ConversationViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = D65B4B6329771EFF00DABDFB /* ConversationViewController.swift */; };
 		D65B4B6629773AE600DABDFB /* DeleteStatusService.swift in Sources */ = {isa = PBXBuildFile; fileRef = D65B4B6529773AE600DABDFB /* DeleteStatusService.swift */; };
+		D65B4B682977769E00DABDFB /* StatusActionAccountListViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = D65B4B672977769E00DABDFB /* StatusActionAccountListViewController.swift */; };
+		D65B4B6A297777D900DABDFB /* StatusNotFoundView.swift in Sources */ = {isa = PBXBuildFile; fileRef = D65B4B69297777D900DABDFB /* StatusNotFoundView.swift */; };
 		D65C6BF525478A9C00A6E89C /* BackgroundableViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = D65C6BF425478A9C00A6E89C /* BackgroundableViewController.swift */; };
 		D65F613423AEAB6600F3CFD3 /* OnboardingTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = D65F613323AEAB6600F3CFD3 /* OnboardingTests.swift */; };
 		D6620ACE2511A0ED00312CA0 /* StatusStateResolver.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6620ACD2511A0ED00312CA0 /* StatusStateResolver.swift */; };
@@ -300,7 +302,7 @@
 		D6CA8CDE296387310050C433 /* SaveToPhotosActivity.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6CA8CDD296387310050C433 /* SaveToPhotosActivity.swift */; };
 		D6D12B2F2925D66500D528E1 /* TimelineGapCollectionViewCell.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6D12B2E2925D66500D528E1 /* TimelineGapCollectionViewCell.swift */; };
 		D6D12B56292D57E800D528E1 /* AccountCollectionViewCell.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6D12B55292D57E800D528E1 /* AccountCollectionViewCell.swift */; };
-		D6D12B58292D5B2C00D528E1 /* StatusActionAccountListViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6D12B57292D5B2C00D528E1 /* StatusActionAccountListViewController.swift */; };
+		D6D12B58292D5B2C00D528E1 /* StatusActionAccountListCollectionViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6D12B57292D5B2C00D528E1 /* StatusActionAccountListCollectionViewController.swift */; };
 		D6D12B5A292D684600D528E1 /* AccountListViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6D12B59292D684600D528E1 /* AccountListViewController.swift */; };
 		D6D3F4C424FDB6B700EC4A6A /* View+ConditionalModifier.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6D3F4C324FDB6B700EC4A6A /* View+ConditionalModifier.swift */; };
 		D6D3FDE224F46A8D00FF50A5 /* ComposeUIState.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6D3FDE124F46A8D00FF50A5 /* ComposeUIState.swift */; };
@@ -543,6 +545,8 @@
 		D65B4B6129771A3F00DABDFB /* FetchStatusService.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = FetchStatusService.swift; sourceTree = "<group>"; };
 		D65B4B6329771EFF00DABDFB /* ConversationViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ConversationViewController.swift; sourceTree = "<group>"; };
 		D65B4B6529773AE600DABDFB /* DeleteStatusService.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = DeleteStatusService.swift; sourceTree = "<group>"; };
+		D65B4B672977769E00DABDFB /* StatusActionAccountListViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = StatusActionAccountListViewController.swift; sourceTree = "<group>"; };
+		D65B4B69297777D900DABDFB /* StatusNotFoundView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = StatusNotFoundView.swift; sourceTree = "<group>"; };
 		D65C6BF425478A9C00A6E89C /* BackgroundableViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = BackgroundableViewController.swift; sourceTree = "<group>"; };
 		D65F612D23AE990C00F3CFD3 /* Embassy.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; path = Embassy.framework; sourceTree = BUILT_PRODUCTS_DIR; };
 		D65F613023AE99E000F3CFD3 /* Ambassador.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; path = Ambassador.framework; sourceTree = BUILT_PRODUCTS_DIR; };
@@ -694,7 +698,7 @@
 		D6CA8CDD296387310050C433 /* SaveToPhotosActivity.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SaveToPhotosActivity.swift; sourceTree = "<group>"; };
 		D6D12B2E2925D66500D528E1 /* TimelineGapCollectionViewCell.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = TimelineGapCollectionViewCell.swift; sourceTree = "<group>"; };
 		D6D12B55292D57E800D528E1 /* AccountCollectionViewCell.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AccountCollectionViewCell.swift; sourceTree = "<group>"; };
-		D6D12B57292D5B2C00D528E1 /* StatusActionAccountListViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = StatusActionAccountListViewController.swift; sourceTree = "<group>"; };
+		D6D12B57292D5B2C00D528E1 /* StatusActionAccountListCollectionViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = StatusActionAccountListCollectionViewController.swift; sourceTree = "<group>"; };
 		D6D12B59292D684600D528E1 /* AccountListViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AccountListViewController.swift; sourceTree = "<group>"; };
 		D6D3F4C324FDB6B700EC4A6A /* View+ConditionalModifier.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "View+ConditionalModifier.swift"; sourceTree = "<group>"; };
 		D6D3FDE124F46A8D00FF50A5 /* ComposeUIState.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ComposeUIState.swift; sourceTree = "<group>"; };
@@ -1292,7 +1296,8 @@
 		D6A3BC8C2321FF9B00FD64D5 /* Status Action Account List */ = {
 			isa = PBXGroup;
 			children = (
-				D6D12B57292D5B2C00D528E1 /* StatusActionAccountListViewController.swift */,
+				D65B4B672977769E00DABDFB /* StatusActionAccountListViewController.swift */,
+				D6D12B57292D5B2C00D528E1 /* StatusActionAccountListCollectionViewController.swift */,
 			);
 			path = "Status Action Account List";
 			sourceTree = "<group>";
@@ -1382,6 +1387,7 @@
 				D6D7069F29466649000827ED /* ScrollingSegmentedControl.swift */,
 				D627943123A5466600D38C68 /* SelectableTableViewCell.swift */,
 				D620483723D38190008A63EF /* StatusContentTextView.swift */,
+				D65B4B69297777D900DABDFB /* StatusNotFoundView.swift */,
 				04ED00B021481ED800567C53 /* SteppedProgressView.swift */,
 				D6093FB625BE0CF3004811E6 /* TrendHistoryView.swift */,
 				D686BBE224FBF8110068E6AA /* WrappedProgressView.swift */,
@@ -1908,6 +1914,7 @@
 				D69693FA25859A8000F4E116 /* ComposeSceneDelegate.swift in Sources */,
 				D6A3BC8A2321F79B00FD64D5 /* AccountTableViewCell.swift in Sources */,
 				D66A77BB233838DC0058F1EC /* UIFont+Traits.swift in Sources */,
+				D65B4B682977769E00DABDFB /* StatusActionAccountListViewController.swift in Sources */,
 				D61F759B29384F9C00C0B37F /* FilterMO.swift in Sources */,
 				D68FEC4F232C5BC300C84F23 /* SegmentedPageViewController.swift in Sources */,
 				D64AAE9126C80DC600FC57FB /* ToastView.swift in Sources */,
@@ -2068,7 +2075,7 @@
 				D620483423D3801D008A63EF /* LinkTextView.swift in Sources */,
 				D61F75882932DB6000C0B37F /* StatusSwipeAction.swift in Sources */,
 				D68A76EA295285D0001DA1B3 /* AddHashtagPinnedTimelineView.swift in Sources */,
-				D6D12B58292D5B2C00D528E1 /* StatusActionAccountListViewController.swift in Sources */,
+				D6D12B58292D5B2C00D528E1 /* StatusActionAccountListCollectionViewController.swift in Sources */,
 				D6412B0D24B0D4CF00F5412E /* ProfileHeaderView.swift in Sources */,
 				D641C77F213DC78A004B4513 /* InlineTextAttachment.swift in Sources */,
 				D61A45E628DC0F2F002BE511 /* ConfirmLoadMoreCollectionViewCell.swift in Sources */,
@@ -2160,6 +2167,7 @@
 				D6E426B325337C7000C02E1C /* CustomEmojiImageView.swift in Sources */,
 				D6D4DDD0212518A000E1C4BB /* AppDelegate.swift in Sources */,
 				D61F75B3293BD89C00C0B37F /* UpdateFilterService.swift in Sources */,
+				D65B4B6A297777D900DABDFB /* StatusNotFoundView.swift in Sources */,
 				D6412B0924B0291E00F5412E /* MyProfileViewController.swift in Sources */,
 				D6D12B56292D57E800D528E1 /* AccountCollectionViewCell.swift in Sources */,
 				D6A6C10525B6138A00298D0F /* StatusTablePrefetching.swift in Sources */,

Tusker/Screens/Conversation/ConversationViewController.swift

@@ -142,7 +142,6 @@ class ConversationViewController: UIViewController {
                 return mastodonController.persistentContainer.addOrUpdateOnViewContext(status: status)
             case .notFound:
                 state = .notFound
-                showMainStatusNotFound()
                 return nil
             case .error(let error):
                 self.showMainStatusError(error)
@@ -209,41 +208,13 @@ class ConversationViewController: UIViewController {
     }
     
     private func showMainStatusNotFound() {
-        let emoji = UILabel()
+        let notFoundView = StatusNotFoundView(frame: .zero)
-        emoji.font = .systemFont(ofSize: 64)
+        notFoundView.translatesAutoresizingMaskIntoConstraints = false
-        emoji.text = "🤷"
+        view.addSubview(notFoundView)
-        
-        let title = UILabel()
-        title.textColor = .secondaryLabel
-        title.font = .preferredFont(forTextStyle: .title1).withTraits(.traitBold)!
-        title.adjustsFontForContentSizeCategory = true
-        title.text = "Not Found"
-        
-        let subtitle = UILabel()
-        subtitle.textColor = .secondaryLabel
-        subtitle.font = .preferredFont(forTextStyle: .body)
-        subtitle.adjustsFontForContentSizeCategory = true
-        subtitle.text = "The post you are looking for may have been deleted, or may not be visible to you."
-        subtitle.numberOfLines = 0
-        subtitle.textAlignment = .center
-        
-        let stack = UIStackView(arrangedSubviews: [
-            emoji,
-            title,
-            subtitle,
-        ])
-        stack.axis = .vertical
-        stack.alignment = .center
-        stack.spacing = 8
-        stack.isAccessibilityElement = true
-        stack.accessibilityLabel = "\(title.text!). \(subtitle.text!)"
-        
-        stack.translatesAutoresizingMaskIntoConstraints = false
-        view.addSubview(stack)
         NSLayoutConstraint.activate([
-            stack.leadingAnchor.constraint(equalToSystemSpacingAfter: view.safeAreaLayoutGuide.leadingAnchor, multiplier: 1),
+            notFoundView.leadingAnchor.constraint(equalToSystemSpacingAfter: view.safeAreaLayoutGuide.leadingAnchor, multiplier: 1),
-            view.safeAreaLayoutGuide.trailingAnchor.constraint(equalToSystemSpacingAfter: stack.trailingAnchor, multiplier: 1),
+            view.safeAreaLayoutGuide.trailingAnchor.constraint(equalToSystemSpacingAfter: notFoundView.trailingAnchor, multiplier: 1),
-            stack.centerYAnchor.constraint(equalTo: view.safeAreaLayoutGuide.centerYAnchor),
+            notFoundView.centerYAnchor.constraint(equalTo: view.safeAreaLayoutGuide.centerYAnchor),
         ])
     }
     
@@ -278,6 +249,13 @@ extension ConversationViewController {
 }
 
 extension ConversationViewController: ToastableViewController {
+    var toastScrollView: UIScrollView? {
+        if case .displaying(let vc) = state {
+            return vc.toastScrollView
+        } else {
+            return nil
+        }
+    }
 }
 
 extension ConversationViewController: StatusBarTappableViewController {

Tusker/Screens/Status Action Account List/StatusActionAccountListCollectionViewController.swift

@@ -0,0 +1,237 @@
+//
+//  StatusActionAccountListCollectionViewController.swift
+//  Tusker
+//
+//  Created by Shadowfacts on 9/5/19.
+//  Copyright © 2019 Shadowfacts. All rights reserved.
+//
+
+import UIKit
+import Pachyderm
+
+class StatusActionAccountListCollectionViewController: UIViewController, CollectionViewController {
+    
+    private let mastodonController: MastodonController
+    
+    /// If `true`, a warning will be shown below the account list describing that the total favs/reblogs may be innacurate.
+    var showInacurateCountWarning = false
+    
+    var collectionView: UICollectionView! {
+        view as? UICollectionView
+    }
+    private var dataSource: UICollectionViewDiffableDataSource<Section, Item>!
+    
+    /**
+     Creates a new view controller showing the accounts that performed the given action on the given status.
+     
+     - Parameter mastodonController The `MastodonController` instance this view controller uses.
+     */
+    init(mastodonController: MastodonController) {
+        self.mastodonController = mastodonController
+        
+        super.init(nibName: nil, bundle: nil)
+        
+    }
+    
+    required init?(coder: NSCoder) {
+        fatalError("init(coder:) has not been implemented")
+    }
+    
+    override func loadView() {
+        let layout = UICollectionViewCompositionalLayout { [unowned self] sectionIndex, environment in
+            switch dataSource.sectionIdentifier(for: sectionIndex)! {
+            case .status:
+                var config = UICollectionLayoutListConfiguration(appearance: .grouped)
+                config.footerMode = self.showInacurateCountWarning ? .supplementary : .none
+                config.leadingSwipeActionsConfigurationProvider = { [unowned self] in
+                    (collectionView.cellForItem(at: $0) as? TimelineStatusCollectionViewCell)?.leadingSwipeActions()
+                }
+                config.trailingSwipeActionsConfigurationProvider = { [unowned self] in
+                    (collectionView.cellForItem(at: $0) as? TimelineStatusCollectionViewCell)?.trailingSwipeActions()
+                }
+                return NSCollectionLayoutSection.list(using: config, layoutEnvironment: environment)
+            case .accounts:
+                return NSCollectionLayoutSection.list(using: .init(appearance: .grouped), layoutEnvironment: environment)
+            }
+        }
+        view = UICollectionView(frame: .zero, collectionViewLayout: layout)
+        collectionView.delegate = self
+        collectionView.dragDelegate = self
+        collectionView.allowsFocus = true
+        dataSource = createDataSource()
+    }
+    
+    private func createDataSource() -> UICollectionViewDiffableDataSource<Section, Item> {
+        let statusCell = UICollectionView.CellRegistration<TimelineStatusCollectionViewCell, (String, CollapseState)> { [unowned self] cell, indexPath, item in
+            cell.delegate = self
+            cell.updateUI(statusID: item.0, state: item.1, filterResult: .allow, precomputedContent: nil)
+        }
+        let accountCell = UICollectionView.CellRegistration<AccountCollectionViewCell, String> { [unowned self] cell, indexPath, item in
+            cell.delegate = self
+            cell.updateUI(accountID: item)
+        }
+        let dataSource = UICollectionViewDiffableDataSource<Section, Item>(collectionView: collectionView) { collectionView, indexPath, itemIdentifier in
+            switch itemIdentifier {
+            case .status(let id, let state):
+                return collectionView.dequeueConfiguredReusableCell(using: statusCell, for: indexPath, item: (id, state))
+            case .account(let id):
+                return collectionView.dequeueConfiguredReusableCell(using: accountCell, for: indexPath, item: id)
+            }
+        }
+        let sectionHeaderCell = UICollectionView.SupplementaryRegistration<UICollectionViewListCell>(elementKind: UICollectionView.elementKindSectionFooter) { (headerView, collectionView, indexPath) in
+            var config = headerView.defaultContentConfiguration()
+            config.text = NSLocalizedString("Favorite and reblog counts for posts originating from instances other than your own may not be accurate.", comment: "shown on lists of status total actions")
+            headerView.contentConfiguration = config
+        }
+        dataSource.supplementaryViewProvider = { collectionView, elementKind, indexPath in
+            return collectionView.dequeueConfiguredReusableSupplementary(using: sectionHeaderCell, for: indexPath)
+        }
+        return dataSource
+    }
+    
+    override func viewWillAppear(_ animated: Bool) {
+        super.viewWillAppear(animated)
+        
+        clearSelectionOnAppear(animated: animated)
+    }
+    
+    func addStatus(_ status: StatusMO, state: CollapseState) {
+        loadViewIfNeeded()
+        
+        var snapshot = NSDiffableDataSourceSnapshot<Section, Item>()
+        snapshot.appendSections([.status, .accounts])
+        snapshot.appendItems([.status(status.id, state)], toSection: .status)
+        dataSource.apply(snapshot, animatingDifferences: false)
+    }
+    
+    func addAccounts(_ accountIDs: [String], animated: Bool) {
+        var snapshot = dataSource.snapshot()
+        snapshot.appendItems(accountIDs.map { .account($0) }, toSection: .accounts)
+        dataSource.apply(snapshot, animatingDifferences: animated)
+    }
+    
+}
+
+extension StatusActionAccountListCollectionViewController {
+    enum Section {
+        case status
+        case accounts
+    }
+    enum Item: Hashable {
+        case status(String, CollapseState)
+        case account(String)
+        
+        static func ==(lhs: Item, rhs: Item) -> Bool {
+            switch (lhs, rhs) {
+            case (.status(let a, _), .status(let b, _)):
+                return a == b
+            case (.account(let a), .account(let b)):
+                return a == b
+            default:
+                return false
+            }
+        }
+        
+        func hash(into hasher: inout Hasher) {
+            switch self {
+            case .status(let id, _):
+                hasher.combine(0)
+                hasher.combine(id)
+            case .account(let id):
+                hasher.combine(1)
+                hasher.combine(id)
+            }
+        }
+    }
+}
+
+extension StatusActionAccountListCollectionViewController: UICollectionViewDelegate {
+    func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
+        switch dataSource.itemIdentifier(for: indexPath) {
+        case nil:
+            return
+        case .status(let id, let state):
+            selected(status: id, state: state.copy())
+        case .account(let id):
+            selected(account: id)
+        }
+    }
+    
+    func collectionView(_ collectionView: UICollectionView, contextMenuConfigurationForItemAt indexPath: IndexPath, point: CGPoint) -> UIContextMenuConfiguration? {
+        guard let item = dataSource.itemIdentifier(for: indexPath),
+              let cell = collectionView.cellForItem(at: indexPath) else {
+            return nil
+        }
+        switch item {
+        case .status:
+            return (cell as? TimelineStatusCollectionViewCell)?.contextMenuConfiguration()
+        case .account(let id):
+            return UIContextMenuConfiguration {
+                ProfileViewController(accountID: id, mastodonController: self.mastodonController)
+            } actionProvider: { _ in
+                UIMenu(children: self.actionsForProfile(accountID: id, source: .view(cell)))
+            }
+        }
+    }
+    
+    func collectionView(_ collectionView: UICollectionView, willPerformPreviewActionForMenuWith configuration: UIContextMenuConfiguration, animator: UIContextMenuInteractionCommitAnimating) {
+        MenuPreviewHelper.willPerformPreviewAction(animator: animator, presenter: self)
+    }
+}
+
+extension StatusActionAccountListCollectionViewController: UICollectionViewDragDelegate {
+    func collectionView(_ collectionView: UICollectionView, itemsForBeginning session: UIDragSession, at indexPath: IndexPath) -> [UIDragItem] {
+        guard let currentAccountID = mastodonController.accountInfo?.id,
+              let item = dataSource.itemIdentifier(for: indexPath) else {
+            return []
+        }
+        let provider: NSItemProvider
+        switch item {
+        case .status(let id, _):
+            guard let status = mastodonController.persistentContainer.status(for: id) else {
+                return []
+            }
+            provider = NSItemProvider(object: status.url! as NSURL)
+            let activity = UserActivityManager.showConversationActivity(mainStatusID: id, accountID: currentAccountID)
+            activity.displaysAuxiliaryScene = true
+            provider.registerObject(activity, visibility: .all)
+        case .account(let id):
+            guard let account = mastodonController.persistentContainer.account(for: id) else {
+                return []
+            }
+            provider = NSItemProvider(object: account.url as NSURL)
+            let activity = UserActivityManager.showProfileActivity(id: account.id, accountID: currentAccountID)
+            activity.displaysAuxiliaryScene = true
+            provider.registerObject(activity, visibility: .all)
+        }
+        return [UIDragItem(itemProvider: provider)]
+    }
+}
+
+extension StatusActionAccountListCollectionViewController: TuskerNavigationDelegate {
+    var apiController: MastodonController! { mastodonController }
+}
+
+extension StatusActionAccountListCollectionViewController: MenuActionProvider {
+}
+
+extension StatusActionAccountListCollectionViewController: StatusCollectionViewCellDelegate {
+    func statusCellNeedsReconfigure(_ cell: StatusCollectionViewCell, animated: Bool, completion: (() -> Void)?) {
+        if let indexPath = collectionView.indexPath(for: cell) {
+            var snapshot = dataSource.snapshot()
+            snapshot.reconfigureItems([dataSource.itemIdentifier(for: indexPath)!])
+            dataSource.apply(snapshot, animatingDifferences: animated, completion: completion)
+        }
+    }
+    
+    func statusCellShowFiltered(_ cell: StatusCollectionViewCell) {
+        fatalError()
+    }
+}
+
+extension StatusActionAccountListCollectionViewController: StatusBarTappableViewController {
+    func handleStatusBarTapped(xPosition: CGFloat) -> StatusBarTapActionResult {
+        collectionView.scrollToTop()
+        return .stop
+    }
+}

Tusker/Screens/Status Action Account List/StatusActionAccountListViewController.swift

@@ -2,28 +2,58 @@
 //  StatusActionAccountListViewController.swift
 //  Tusker
 //
-//  Created by Shadowfacts on 9/5/19.
+//  Created by Shadowfacts on 1/17/23.
-//  Copyright © 2019 Shadowfacts. All rights reserved.
+//  Copyright © 2023 Shadowfacts. All rights reserved.
 //
 
 import UIKit
 import Pachyderm
 
-class StatusActionAccountListViewController: UIViewController, CollectionViewController {
+class StatusActionAccountListViewController: UIViewController {
     
     private let mastodonController: MastodonController
-    private let actionType: ActionType
+    private let actionType: StatusActionAccountListViewController.ActionType
     private let statusID: String
     private let statusState: CollapseState
     private var accountIDs: [String]?
     
     /// If `true`, a warning will be shown below the account list describing that the total favs/reblogs may be innacurate.
-    var showInacurateCountWarning = false
+    var showInacurateCountWarning = false {
-    
+        didSet {
-    var collectionView: UICollectionView! {
+            if case .displaying(let vc) = state {
-        view as? UICollectionView
+                vc.showInacurateCountWarning = showInacurateCountWarning
+            }
+        }
+    }
+    
+    private var state: State = .unloaded {
+        didSet {
+            switch oldValue {
+            case .loading(let indicator):
+                indicator.removeFromSuperview()
+            case .displaying(let vc):
+                vc.removeViewAndController()
+            default:
+                break
+            }
+            
+            switch state {
+            case .unloaded:
+                break
+            case .loading(let indicator):
+                indicator.translatesAutoresizingMaskIntoConstraints = false
+                view.addSubview(indicator)
+                NSLayoutConstraint.activate([
+                    indicator.centerXAnchor.constraint(equalTo: view.safeAreaLayoutGuide.centerXAnchor),
+                    indicator.centerYAnchor.constraint(equalTo: view.safeAreaLayoutGuide.centerYAnchor),
+                ])
+            case .displaying(let vc):
+                embedChild(vc)
+            case .notFound:
+                showStatusNotFound()
+            }
+        }
     }
-    private var dataSource: UICollectionViewDiffableDataSource<Section, Item>!
     
     /**
      Creates a new view controller showing the accounts that performed the given action on the given status.
@@ -33,14 +63,22 @@ class StatusActionAccountListViewController: UIViewController, CollectionViewCon
      - Parameter accountIDs The accounts that will be shown. If `nil` is passed, a request will be performed to load the accounts.
      - Parameter mastodonController The `MastodonController` instance this view controller uses.
      */
-    init(actionType: ActionType, statusID: String, statusState: CollapseState, accountIDs: [String]?, mastodonController: MastodonController) {
+    init(actionType: StatusActionAccountListViewController.ActionType, statusID: String, statusState: CollapseState, accountIDs: [String]?, mastodonController: MastodonController) {
         self.mastodonController = mastodonController
         self.actionType = actionType
         self.statusID = statusID
         self.statusState = statusState
         self.accountIDs = accountIDs
-        
+
         super.init(nibName: nil, bundle: nil)
+    }
+    
+    required init?(coder: NSCoder) {
+        fatalError("init(coder:) has not been implemented")
+    }
+    
+    override func viewDidLoad() {
+        super.viewDidLoad()
         
         switch actionType {
         case .favorite:
@@ -48,89 +86,76 @@ class StatusActionAccountListViewController: UIViewController, CollectionViewCon
         case .reblog:
             title = NSLocalizedString("Reblogged By", comment: "status reblogged by accounts list title")
         }
-    }
-    
-    required init?(coder: NSCoder) {
-        fatalError("init(coder:) has not been implemented")
-    }
-    
-    override func loadView() {
-        let layout = UICollectionViewCompositionalLayout { [unowned self] sectionIndex, environment in
-            switch dataSource.sectionIdentifier(for: sectionIndex)! {
-            case .status:
-                var config = UICollectionLayoutListConfiguration(appearance: .grouped)
-                config.footerMode = self.showInacurateCountWarning ? .supplementary : .none
-                config.leadingSwipeActionsConfigurationProvider = { [unowned self] in
-                    (collectionView.cellForItem(at: $0) as? TimelineStatusCollectionViewCell)?.leadingSwipeActions()
-                }
-                config.trailingSwipeActionsConfigurationProvider = { [unowned self] in
-                    (collectionView.cellForItem(at: $0) as? TimelineStatusCollectionViewCell)?.trailingSwipeActions()
-                }
-                return NSCollectionLayoutSection.list(using: config, layoutEnvironment: environment)
-            case .accounts:
-                return NSCollectionLayoutSection.list(using: .init(appearance: .grouped), layoutEnvironment: environment)
-            }
-        }
-        view = UICollectionView(frame: .zero, collectionViewLayout: layout)
-        collectionView.delegate = self
-        collectionView.dragDelegate = self
-        collectionView.allowsFocus = true
-        dataSource = createDataSource()
-    }
-    
-    private func createDataSource() -> UICollectionViewDiffableDataSource<Section, Item> {
-        let statusCell = UICollectionView.CellRegistration<TimelineStatusCollectionViewCell, Void> { [unowned self] cell, indexPath, _ in
-            cell.delegate = self
-            cell.updateUI(statusID: self.statusID, state: self.statusState, filterResult: .allow, precomputedContent: nil)
-        }
-        let accountCell = UICollectionView.CellRegistration<AccountCollectionViewCell, String> { [unowned self] cell, indexPath, item in
-            cell.delegate = self
-            cell.updateUI(accountID: item)
-        }
-        let dataSource = UICollectionViewDiffableDataSource<Section, Item>(collectionView: collectionView) { collectionView, indexPath, itemIdentifier in
-            switch itemIdentifier {
-            case .status:
-                return collectionView.dequeueConfiguredReusableCell(using: statusCell, for: indexPath, item: ())
-            case .account(let id):
-                return collectionView.dequeueConfiguredReusableCell(using: accountCell, for: indexPath, item: id)
-            }
-        }
-        let sectionHeaderCell = UICollectionView.SupplementaryRegistration<UICollectionViewListCell>(elementKind: UICollectionView.elementKindSectionFooter) { (headerView, collectionView, indexPath) in
-            var config = headerView.defaultContentConfiguration()
-            config.text = NSLocalizedString("Favorite and reblog counts for posts originating from instances other than your own may not be accurate.", comment: "shown on lists of status total actions")
-            headerView.contentConfiguration = config
-        }
-        dataSource.supplementaryViewProvider = { collectionView, elementKind, indexPath in
-            return collectionView.dequeueConfiguredReusableSupplementary(using: sectionHeaderCell, for: indexPath)
-        }
-        return dataSource
-    }
-    
-    override func viewDidLoad() {
-        super.viewDidLoad()
 
-        var snapshot = NSDiffableDataSourceSnapshot<Section, Item>()
+        view.backgroundColor = .secondarySystemBackground
-        snapshot.appendSections([.status, .accounts])
+        
-        snapshot.appendItems([.status], toSection: .status)
+        NotificationCenter.default.addObserver(self, selector: #selector(handleStatusDeleted), name: .statusDeleted, object: nil)
-        if let accountIDs {
-            snapshot.appendItems(accountIDs.map { .account($0) }, toSection: .accounts)
-        }
-        dataSource.apply(snapshot, animatingDifferences: false)
     }
     
     override func viewWillAppear(_ animated: Bool) {
         super.viewWillAppear(animated)
         
-        clearSelectionOnAppear(animated: animated)
+        Task {
-        
+            await loadStatus()
-        if accountIDs == nil {
+        }
-            Task {
+    }
-                await loadAccounts()
+    
+    @objc private func handleStatusDeleted(_ notification: Foundation.Notification) {
+        guard let userInfo = notification.userInfo,
+              let accountID = mastodonController.accountInfo?.id,
+              userInfo["accountID"] as? String == accountID,
+              let statusIDs = userInfo["statusIDs"] as? [String] else {
+            return
+        }
+        if statusIDs.contains(statusID) {
+            state = .notFound
+        }
+    }
+    
+    // MARK: Loading
+    
+    private func loadStatus() async {
+        @MainActor
+        func doLoadStatus() async -> StatusMO? {
+            switch await FetchStatusService(statusID: statusID, mastodonController: mastodonController).run() {
+            case .loaded(let status):
+                return mastodonController.persistentContainer.addOrUpdateOnViewContext(status: status)
+            case .notFound:
+                state = .notFound
+                return nil
+            case .error(let error):
+                self.showStatusError(error)
+                return nil
+            }
+        }
+
+        if let cached = mastodonController.persistentContainer.status(for: statusID) {
+            await statusLoaded(cached)
+        } else {
+            let indicator = UIActivityIndicatorView(style: .medium)
+            indicator.startAnimating()
+            state = .loading(indicator)
+
+            if let status = await doLoadStatus() {
+                await statusLoaded(status)
             }
         }
     }
     
-    private func loadAccounts() async {
+    private func statusLoaded(_ status: StatusMO) async {
+        let vc = StatusActionAccountListCollectionViewController(mastodonController: mastodonController)
+        vc.addStatus(status, state: statusState)
+        vc.showInacurateCountWarning = showInacurateCountWarning
+        state = .displaying(vc)
+        
+        if let accountIDs {
+            vc.addAccounts(accountIDs, animated: false)
+        } else {
+            await loadAccounts(list: vc)
+        }
+    }
+    
+    private func loadAccounts(list: StatusActionAccountListCollectionViewController) async {
         let request: Request<[Account]>
         switch actionType {
         case .favorite:
@@ -148,20 +173,45 @@ class StatusActionAccountListViewController: UIViewController, CollectionViewCon
                 }
             }
             
-            accountIDs = accounts.map(\.id)
+            list.addAccounts(accounts.map(\.id), animated: true)
-            
-            var snapshot = dataSource.snapshot()
-            snapshot.appendItems(accounts.map { .account($0.id) }, toSection: .accounts)
-            dataSource.apply(snapshot, animatingDifferences: true) {}
             
         } catch {
             let config = ToastConfiguration(from: error, with: "Error Loading Accounts", in: self) { toast in
                 toast.dismissToast(animated: true)
-                await self.loadAccounts()
+                await self.loadAccounts(list: list)
             }
             self.showToast(configuration: config, animated: true)
         }
     }
+    
+    private func showStatusNotFound() {
+        let notFoundView = StatusNotFoundView(frame: .zero)
+        notFoundView.translatesAutoresizingMaskIntoConstraints = false
+        view.addSubview(notFoundView)
+        NSLayoutConstraint.activate([
+            notFoundView.leadingAnchor.constraint(equalToSystemSpacingAfter: view.safeAreaLayoutGuide.leadingAnchor, multiplier: 1),
+            view.safeAreaLayoutGuide.trailingAnchor.constraint(equalToSystemSpacingAfter: notFoundView.trailingAnchor, multiplier: 1),
+            notFoundView.centerYAnchor.constraint(equalTo: view.safeAreaLayoutGuide.centerYAnchor),
+        ])
+    }
+    
+    private func showStatusError(_ error: Client.Error) {
+        let config = ToastConfiguration(from: error, with: "Error Loading Status", in: self) { [weak self] toast in
+            toast.dismissToast(animated: true)
+            await self?.loadStatus()
+        }
+        self.showToast(configuration: config, animated: true)
+    }
+
+}
+
+extension StatusActionAccountListViewController {
+    enum State {
+        case unloaded
+        case loading(UIActivityIndicatorView)
+        case displaying(StatusActionAccountListCollectionViewController)
+        case notFound
+    }
 }
 
 extension StatusActionAccountListViewController {
@@ -170,104 +220,12 @@ extension StatusActionAccountListViewController {
     }
 }
 
-extension StatusActionAccountListViewController {
+extension StatusActionAccountListViewController: ToastableViewController {
-    enum Section {
+    var toastScrollView: UIScrollView? {
-        case status
+        if case .displaying(let vc) = state {
-        case accounts
+            return vc.toastScrollView
-    }
+        } else {
-    enum Item: Hashable {
-        case status
-        case account(String)
-    }
-}
-
-extension StatusActionAccountListViewController: UICollectionViewDelegate {
-    func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
-        switch dataSource.itemIdentifier(for: indexPath) {
-        case nil:
-            return
-        case .status:
-            selected(status: statusID, state: statusState.copy())
-        case .account(let id):
-            selected(account: id)
-        }
-    }
-    
-    func collectionView(_ collectionView: UICollectionView, contextMenuConfigurationForItemAt indexPath: IndexPath, point: CGPoint) -> UIContextMenuConfiguration? {
-        guard let item = dataSource.itemIdentifier(for: indexPath),
-              let cell = collectionView.cellForItem(at: indexPath) else {
             return nil
         }
-        switch item {
-        case .status:
-            return (cell as? TimelineStatusCollectionViewCell)?.contextMenuConfiguration()
-        case .account(let id):
-            return UIContextMenuConfiguration {
-                ProfileViewController(accountID: id, mastodonController: self.mastodonController)
-            } actionProvider: { _ in
-                UIMenu(children: self.actionsForProfile(accountID: id, source: .view(cell)))
-            }
-        }
-    }
-    
-    func collectionView(_ collectionView: UICollectionView, willPerformPreviewActionForMenuWith configuration: UIContextMenuConfiguration, animator: UIContextMenuInteractionCommitAnimating) {
-        MenuPreviewHelper.willPerformPreviewAction(animator: animator, presenter: self)
-    }
-}
-
-extension StatusActionAccountListViewController: UICollectionViewDragDelegate {
-    func collectionView(_ collectionView: UICollectionView, itemsForBeginning session: UIDragSession, at indexPath: IndexPath) -> [UIDragItem] {
-        guard let currentAccountID = mastodonController.accountInfo?.id,
-              let item = dataSource.itemIdentifier(for: indexPath) else {
-            return []
-        }
-        let provider: NSItemProvider
-        switch item {
-        case .status:
-            guard let status = mastodonController.persistentContainer.status(for: statusID) else {
-                return []
-            }
-            provider = NSItemProvider(object: status.url! as NSURL)
-            let activity = UserActivityManager.showConversationActivity(mainStatusID: statusID, accountID: currentAccountID)
-            activity.displaysAuxiliaryScene = true
-            provider.registerObject(activity, visibility: .all)
-        case .account(let id):
-            guard let account = mastodonController.persistentContainer.account(for: id) else {
-                return []
-            }
-            provider = NSItemProvider(object: account.url as NSURL)
-            let activity = UserActivityManager.showProfileActivity(id: account.id, accountID: currentAccountID)
-            activity.displaysAuxiliaryScene = true
-            provider.registerObject(activity, visibility: .all)
-        }
-        return [UIDragItem(itemProvider: provider)]
-    }
-}
-
-extension StatusActionAccountListViewController: TuskerNavigationDelegate {
-    var apiController: MastodonController! { mastodonController }
-}
-
-extension StatusActionAccountListViewController: MenuActionProvider {
-}
-
-extension StatusActionAccountListViewController: StatusCollectionViewCellDelegate {
-    func statusCellNeedsReconfigure(_ cell: StatusCollectionViewCell, animated: Bool, completion: (() -> Void)?) {
-        if let indexPath = collectionView.indexPath(for: cell) {
-            var snapshot = dataSource.snapshot()
-            snapshot.reconfigureItems([dataSource.itemIdentifier(for: indexPath)!])
-            dataSource.apply(snapshot, animatingDifferences: animated, completion: completion)
-        }
-    }
-    
-    func statusCellShowFiltered(_ cell: StatusCollectionViewCell) {
-        fatalError()
-    }
-}
-
-extension StatusActionAccountListViewController: StatusBarTappableViewController {
-    func handleStatusBarTapped(xPosition: CGFloat) -> StatusBarTapActionResult {
-        collectionView.scrollToTop()
-        return .stop
     }
 }

Tusker/Views/StatusNotFoundView.swift

@@ -0,0 +1,60 @@
+//
+//  StatusNotFoundView.swift
+//  Tusker
+//
+//  Created by Shadowfacts on 1/17/23.
+//  Copyright © 2023 Shadowfacts. All rights reserved.
+//
+
+import UIKit
+
+class StatusNotFoundView: UIView {
+
+    override init(frame: CGRect) {
+        super.init(frame: frame)
+        
+        let emoji = UILabel()
+        emoji.font = .systemFont(ofSize: 64)
+        emoji.text = "🤷"
+        
+        let title = UILabel()
+        title.textColor = .secondaryLabel
+        title.font = .preferredFont(forTextStyle: .title1).withTraits(.traitBold)!
+        title.adjustsFontForContentSizeCategory = true
+        title.text = "Not Found"
+        
+        let subtitle = UILabel()
+        subtitle.textColor = .secondaryLabel
+        subtitle.font = .preferredFont(forTextStyle: .body)
+        subtitle.adjustsFontForContentSizeCategory = true
+        subtitle.text = "The post you are looking for may have been deleted, or may not be visible to you."
+        subtitle.numberOfLines = 0
+        subtitle.textAlignment = .center
+        
+        let stack = UIStackView(arrangedSubviews: [
+            emoji,
+            title,
+            subtitle,
+        ])
+        stack.axis = .vertical
+        stack.alignment = .center
+        stack.spacing = 8
+        stack.isAccessibilityElement = true
+        stack.accessibilityLabel = "\(title.text!). \(subtitle.text!)"
+        
+        stack.translatesAutoresizingMaskIntoConstraints = false
+        addSubview(stack)
+        NSLayoutConstraint.activate([
+            stack.leadingAnchor.constraint(equalTo: leadingAnchor),
+            stack.trailingAnchor.constraint(equalTo: trailingAnchor),
+            stack.topAnchor.constraint(equalTo: topAnchor),
+            stack.bottomAnchor.constraint(equalTo: bottomAnchor),
+        ])
+    }
+    
+    required init?(coder: NSCoder) {
+        fatalError("init(coder:) has not been implemented")
+    }
+    
+
+}