Switch everything to new profile view controller

Tusker.xcodeproj/project.pbxproj

@@ -36,12 +36,15 @@
 		D61A45E828DF477D002BE511 /* LoadingCollectionViewCell.swift in Sources */ = {isa = PBXBuildFile; fileRef = D61A45E728DF477D002BE511 /* LoadingCollectionViewCell.swift */; };
 		D61A45EA28DF51EE002BE511 /* TimelineLikeCollectionViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = D61A45E928DF51EE002BE511 /* TimelineLikeCollectionViewController.swift */; };
 		D61ABEF628EE74D400B29151 /* StatusCollectionViewCell.swift in Sources */ = {isa = PBXBuildFile; fileRef = D61ABEF528EE74D400B29151 /* StatusCollectionViewCell.swift */; };
+		D61ABEF828EFC3F900B29151 /* ProfileStatusesViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = D61ABEF728EFC3F900B29151 /* ProfileStatusesViewController.swift */; };
 		D61ABEFC28F105DE00B29151 /* Pachyderm in Frameworks */ = {isa = PBXBuildFile; productRef = D61ABEFB28F105DE00B29151 /* Pachyderm */; };
 		D61ABEFE28F1C92600B29151 /* FavoriteService.swift in Sources */ = {isa = PBXBuildFile; fileRef = D61ABEFD28F1C92600B29151 /* FavoriteService.swift */; };
 		D61AC1D5232E9FA600C54D2D /* InstanceSelectorTableViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = D61AC1D4232E9FA600C54D2D /* InstanceSelectorTableViewController.swift */; };
 		D61AC1D8232EA42D00C54D2D /* InstanceTableViewCell.swift in Sources */ = {isa = PBXBuildFile; fileRef = D61AC1D6232EA42D00C54D2D /* InstanceTableViewCell.swift */; };
 		D61AC1D9232EA42D00C54D2D /* InstanceTableViewCell.xib in Resources */ = {isa = PBXBuildFile; fileRef = D61AC1D7232EA42D00C54D2D /* InstanceTableViewCell.xib */; };
 		D61DC84628F498F200B82C6E /* Logging.swift in Sources */ = {isa = PBXBuildFile; fileRef = D61DC84528F498F200B82C6E /* Logging.swift */; };
+		D61DC84B28F4FD2000B82C6E /* ProfileHeaderCollectionViewCell.swift in Sources */ = {isa = PBXBuildFile; fileRef = D61DC84A28F4FD2000B82C6E /* ProfileHeaderCollectionViewCell.swift */; };
+		D61DC84D28F500D200B82C6E /* ProfileViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = D61DC84C28F500D200B82C6E /* ProfileViewController.swift */; };
 		D620483423D3801D008A63EF /* LinkTextView.swift in Sources */ = {isa = PBXBuildFile; fileRef = D620483323D3801D008A63EF /* LinkTextView.swift */; };
 		D620483623D38075008A63EF /* ContentTextView.swift in Sources */ = {isa = PBXBuildFile; fileRef = D620483523D38075008A63EF /* ContentTextView.swift */; };
 		D620483823D38190008A63EF /* StatusContentTextView.swift in Sources */ = {isa = PBXBuildFile; fileRef = D620483723D38190008A63EF /* StatusContentTextView.swift */; };
@@ -92,13 +95,11 @@
 		D6333B792139AEFD00CE884A /* Date+TimeAgo.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6333B782139AEFD00CE884A /* Date+TimeAgo.swift */; };
 		D63661C02381C144004B9E16 /* PreferencesNavigationController.swift in Sources */ = {isa = PBXBuildFile; fileRef = D63661BF2381C144004B9E16 /* PreferencesNavigationController.swift */; };
 		D6370B9C24421FF30092A7FF /* Tusker.xcdatamodeld in Sources */ = {isa = PBXBuildFile; fileRef = D6370B9A24421FF30092A7FF /* Tusker.xcdatamodeld */; };
-		D63A8D0B2561C27F00D9DFFF /* ProfileStatusesViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = D63A8D0A2561C27F00D9DFFF /* ProfileStatusesViewController.swift */; };
 		D63D8DF42850FE7A008D95E1 /* ViewTags.swift in Sources */ = {isa = PBXBuildFile; fileRef = D63D8DF32850FE7A008D95E1 /* ViewTags.swift */; };
 		D63F9C6E241D2D85004C03CF /* CompositionAttachment.swift in Sources */ = {isa = PBXBuildFile; fileRef = D63F9C6D241D2D85004C03CF /* CompositionAttachment.swift */; };
 		D6403CC224A6B72D00E81C55 /* VisualEffectImageButton.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6403CC124A6B72D00E81C55 /* VisualEffectImageButton.swift */; };
 		D640D76922BAF5E6004FBE69 /* DomainBlocks.plist in Resources */ = {isa = PBXBuildFile; fileRef = D640D76822BAF5E6004FBE69 /* DomainBlocks.plist */; };
 		D6412B0324AFF6A600F5412E /* TabBarScrollableViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6412B0224AFF6A600F5412E /* TabBarScrollableViewController.swift */; };
-		D6412B0524B0227D00F5412E /* ProfileViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6412B0424B0227D00F5412E /* ProfileViewController.swift */; };
 		D6412B0924B0291E00F5412E /* MyProfileViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6412B0824B0291E00F5412E /* MyProfileViewController.swift */; };
 		D6412B0B24B0D4C600F5412E /* ProfileHeaderView.xib in Resources */ = {isa = PBXBuildFile; fileRef = D6412B0A24B0D4C600F5412E /* ProfileHeaderView.xib */; };
 		D6412B0D24B0D4CF00F5412E /* ProfileHeaderView.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6412B0C24B0D4CF00F5412E /* ProfileHeaderView.swift */; };
@@ -389,11 +390,14 @@
 		D61A45E728DF477D002BE511 /* LoadingCollectionViewCell.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = LoadingCollectionViewCell.swift; sourceTree = "<group>"; };
 		D61A45E928DF51EE002BE511 /* TimelineLikeCollectionViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = TimelineLikeCollectionViewController.swift; sourceTree = "<group>"; };
 		D61ABEF528EE74D400B29151 /* StatusCollectionViewCell.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = StatusCollectionViewCell.swift; sourceTree = "<group>"; };
+		D61ABEF728EFC3F900B29151 /* ProfileStatusesViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ProfileStatusesViewController.swift; sourceTree = "<group>"; };
 		D61ABEFD28F1C92600B29151 /* FavoriteService.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = FavoriteService.swift; sourceTree = "<group>"; };
 		D61AC1D4232E9FA600C54D2D /* InstanceSelectorTableViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = InstanceSelectorTableViewController.swift; sourceTree = "<group>"; };
 		D61AC1D6232EA42D00C54D2D /* InstanceTableViewCell.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = InstanceTableViewCell.swift; sourceTree = "<group>"; };
 		D61AC1D7232EA42D00C54D2D /* InstanceTableViewCell.xib */ = {isa = PBXFileReference; lastKnownFileType = file.xib; path = InstanceTableViewCell.xib; sourceTree = "<group>"; };
 		D61DC84528F498F200B82C6E /* Logging.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Logging.swift; sourceTree = "<group>"; };
+		D61DC84A28F4FD2000B82C6E /* ProfileHeaderCollectionViewCell.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ProfileHeaderCollectionViewCell.swift; sourceTree = "<group>"; };
+		D61DC84C28F500D200B82C6E /* ProfileViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ProfileViewController.swift; sourceTree = "<group>"; };
 		D620483323D3801D008A63EF /* LinkTextView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = LinkTextView.swift; sourceTree = "<group>"; };
 		D620483523D38075008A63EF /* ContentTextView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ContentTextView.swift; sourceTree = "<group>"; };
 		D620483723D38190008A63EF /* StatusContentTextView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = StatusContentTextView.swift; sourceTree = "<group>"; };
@@ -444,13 +448,11 @@
 		D6333B782139AEFD00CE884A /* Date+TimeAgo.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "Date+TimeAgo.swift"; sourceTree = "<group>"; };
 		D63661BF2381C144004B9E16 /* PreferencesNavigationController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PreferencesNavigationController.swift; sourceTree = "<group>"; };
 		D6370B9B24421FF30092A7FF /* Tusker.xcdatamodel */ = {isa = PBXFileReference; lastKnownFileType = wrapper.xcdatamodel; path = Tusker.xcdatamodel; sourceTree = "<group>"; };
-		D63A8D0A2561C27F00D9DFFF /* ProfileStatusesViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ProfileStatusesViewController.swift; sourceTree = "<group>"; };
 		D63D8DF32850FE7A008D95E1 /* ViewTags.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ViewTags.swift; sourceTree = "<group>"; };
 		D63F9C6D241D2D85004C03CF /* CompositionAttachment.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = CompositionAttachment.swift; sourceTree = "<group>"; };
 		D6403CC124A6B72D00E81C55 /* VisualEffectImageButton.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = VisualEffectImageButton.swift; sourceTree = "<group>"; };
 		D640D76822BAF5E6004FBE69 /* DomainBlocks.plist */ = {isa = PBXFileReference; lastKnownFileType = text.plist.xml; path = DomainBlocks.plist; sourceTree = "<group>"; };
 		D6412B0224AFF6A600F5412E /* TabBarScrollableViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = TabBarScrollableViewController.swift; sourceTree = "<group>"; };
-		D6412B0424B0227D00F5412E /* ProfileViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ProfileViewController.swift; sourceTree = "<group>"; };
 		D6412B0824B0291E00F5412E /* MyProfileViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MyProfileViewController.swift; sourceTree = "<group>"; };
 		D6412B0A24B0D4C600F5412E /* ProfileHeaderView.xib */ = {isa = PBXFileReference; lastKnownFileType = file.xib; path = ProfileHeaderView.xib; sourceTree = "<group>"; };
 		D6412B0C24B0D4CF00F5412E /* ProfileHeaderView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ProfileHeaderView.swift; sourceTree = "<group>"; };
@@ -941,9 +943,10 @@
 		D641C784213DD819004B4513 /* Profile */ = {
 			isa = PBXGroup;
 			children = (
-				D6412B0424B0227D00F5412E /* ProfileViewController.swift */,
-				D63A8D0A2561C27F00D9DFFF /* ProfileStatusesViewController.swift */,
 				D6412B0824B0291E00F5412E /* MyProfileViewController.swift */,
+				D61DC84C28F500D200B82C6E /* ProfileViewController.swift */,
+				D61ABEF728EFC3F900B29151 /* ProfileStatusesViewController.swift */,
+				D61DC84A28F4FD2000B82C6E /* ProfileHeaderCollectionViewCell.swift */,
 			);
 			path = Profile;
 			sourceTree = "<group>";
@@ -1808,7 +1811,6 @@
 				D62D2422217AA7E1005076CC /* UserActivityManager.swift in Sources */,
 				D6CA6A92249FAD8900AD45C1 /* AudioSessionHelper.swift in Sources */,
 				D60D2B8223844C71001B87A3 /* BaseStatusTableViewCell.swift in Sources */,
-				D63A8D0B2561C27F00D9DFFF /* ProfileStatusesViewController.swift in Sources */,
 				D6B9366F2828452F00237D0E /* SavedHashtag.swift in Sources */,
 				D6B9366D2828445000237D0E /* SavedInstance.swift in Sources */,
 				D60E2F272442372B005F8713 /* StatusMO.swift in Sources */,
@@ -1829,6 +1831,7 @@
 				D681E4D5246E2BC30053414F /* UnmuteConversationActivity.swift in Sources */,
 				D6B4A4FF2506B81A000C81C1 /* AccountDisplayNameLabel.swift in Sources */,
 				D63D8DF42850FE7A008D95E1 /* ViewTags.swift in Sources */,
+				D61DC84B28F4FD2000B82C6E /* ProfileHeaderCollectionViewCell.swift in Sources */,
 				D6B053A623BD2D0C00A066FA /* AssetCollectionViewController.swift in Sources */,
 				D61A45E828DF477D002BE511 /* LoadingCollectionViewCell.swift in Sources */,
 				D67B506D250B291200FAECFB /* BlurHashDecode.swift in Sources */,
@@ -1855,6 +1858,7 @@
 				D623A5412635FB3C0095BD04 /* PollOptionView.swift in Sources */,
 				D65C6BF525478A9C00A6E89C /* BackgroundableViewController.swift in Sources */,
 				D6AEBB4A23216F0400E5038B /* UnfollowAccountActivity.swift in Sources */,
+				D61DC84D28F500D200B82C6E /* ProfileViewController.swift in Sources */,
 				D663626421360D2300C9CBA2 /* AvatarStyle.swift in Sources */,
 				D6D3FDE024F41B8400FF50A5 /* ComposeContainerView.swift in Sources */,
 				D693A72A25CF8C1E003A14E2 /* ProfileDirectoryViewController.swift in Sources */,
@@ -1950,6 +1954,7 @@
 				D66362752137068A00C9CBA2 /* Visibility+Helpers.swift in Sources */,
 				D6DFC6A0242C4CCC00ACC392 /* WeakArray.swift in Sources */,
 				D6C693FC2162FE6F007D6A6D /* LoadingViewController.swift in Sources */,
+				D61ABEF828EFC3F900B29151 /* ProfileStatusesViewController.swift in Sources */,
 				D6ADB6EA28E91C30009924AB /* TimelineStatusCollectionViewCell.swift in Sources */,
 				D681E4D7246E32290053414F /* StatusActivityItemSource.swift in Sources */,
 				D646C95A213B5D0500269FB5 /* LargeImageInteractionController.swift in Sources */,
@@ -1969,7 +1974,6 @@
 				D62E9987279D094F00C26176 /* StatusMetaIndicatorsView.swift in Sources */,
 				04D14BB022B34A2800642648 /* GalleryViewController.swift in Sources */,
 				D6C1B2082545D1EC00DAAA66 /* StatusCardView.swift in Sources */,
-				D6412B0524B0227D00F5412E /* ProfileViewController.swift in Sources */,
 				D64BC18A23C16487000D0238 /* UnpinStatusActivity.swift in Sources */,
 				D64D8CA92463B494006B0BAA /* MultiThreadDictionary.swift in Sources */,
 				D65234D325618EFA001AF9CF /* TimelineTableViewController.swift in Sources */,

Tusker/CoreData/MastodonCachePersistentStore.swift

@@ -35,6 +35,9 @@ class MastodonCachePersistentStore: NSPersistentContainer {
         return context
     }()
     
+    // TODO: consider sending managed objects through this to avoid re-fetching things unnecessarily
+    // would need to audit existing uses to make sure everything happens on the main thread
+    // and when updating things on the background context would need to switch to main, refetch, and then publish
     let statusSubject = PassthroughSubject<String, Never>()
     let accountSubject = PassthroughSubject<String, Never>()
     let relationshipSubject = PassthroughSubject<String, Never>()

Tusker/Screens/Profile/ProfileHeaderCollectionViewCell.swift

@@ -0,0 +1,62 @@
+//
+//  ProfileHeaderCollectionViewCell.swift
+//  Tusker
+//
+//  Created by Shadowfacts on 10/10/22.
+//  Copyright © 2022 Shadowfacts. All rights reserved.
+//
+
+import UIKit
+
+class ProfileHeaderCollectionViewCell: UICollectionViewCell {
+    
+    private var state: State = .unloaded
+    
+    override init(frame: CGRect) {
+        super.init(frame: frame)
+        
+        contentView.backgroundColor = .systemBackground
+        isOpaque = true
+        contentView.isOpaque = true
+    }
+    
+    required init?(coder: NSCoder) {
+        fatalError("init(coder:) has not been implemented")
+    }
+    
+    func addHeader(_ header: ProfileHeaderView) {
+        switch state {
+        case .unloaded, .placeholder(heightConstraint: _):
+            header.translatesAutoresizingMaskIntoConstraints = false
+            contentView.embedSubview(header)
+            self.state = .view(header)
+        case .view(_):
+            fatalError("profile header collection view cell already has view")
+        }
+    }
+    
+    func addConstraint(height: CGFloat) -> ProfileHeaderView? {
+        switch state {
+        case .unloaded:
+            let constraint = contentView.heightAnchor.constraint(equalToConstant: height)
+            constraint.isActive = true
+            state = .placeholder(heightConstraint: constraint)
+            return nil
+        case .placeholder(let heightConstraint):
+            heightConstraint.constant = height
+            return nil
+        case .view(let header):
+            let constraint = contentView.heightAnchor.constraint(equalToConstant: height)
+            constraint.isActive = true
+            state = .placeholder(heightConstraint: constraint)
+            return header
+        }
+    }
+    
+    enum State {
+        case unloaded
+        case placeholder(heightConstraint: NSLayoutConstraint)
+        case view(ProfileHeaderView)
+    }
+    
+}

Tusker/Screens/Profile/ProfileStatusesViewController.swift

@@ -2,234 +2,222 @@
 //  ProfileStatusesViewController.swift
 //  Tusker
 //
-//  Created by Shadowfacts on 7/3/20.
+//  Created by Shadowfacts on 10/6/22.
-//  Copyright © 2020 Shadowfacts. All rights reserved.
+//  Copyright © 2022 Shadowfacts. All rights reserved.
 //
 
 import UIKit
 import Pachyderm
+import Combine
 
-class ProfileStatusesViewController: DiffableTimelineLikeTableViewController<ProfileStatusesViewController.Section, ProfileStatusesViewController.Item> {
+class ProfileStatusesViewController: UIViewController, TimelineLikeCollectionViewController {
-    
-    weak var mastodonController: MastodonController!
-    
-    private(set) var headerView: ProfileHeaderView!
-    
-    var accountID: String!
     
+    unowned var owner: ProfileViewController
+    var mastodonController: MastodonController { owner.mastodonController }
+    private(set) var accountID: String!
     let kind: Kind
+    var initialHeaderMode: HeaderMode?
+    weak var profileHeaderDelegate: ProfileHeaderViewDelegate?
     
-    private var older: RequestRange?
+    private(set) var controller: TimelineLikeController<TimelineItem>!
+    let confirmLoadMore = PassthroughSubject<Void, Never>()
     private var newer: RequestRange?
+    private var older: RequestRange?
+    private var cancellables = Set<AnyCancellable>()
     
-    init(accountID: String?, kind: Kind, mastodonController: MastodonController) {
+    var collectionView: UICollectionView {
+        view as! UICollectionView
+    }
+    private(set) var dataSource: UICollectionViewDiffableDataSource<Section, Item>!
+    
+    private(set) var headerCell: ProfileHeaderCollectionViewCell?
+    
+    init(accountID: String?, kind: Kind, owner: ProfileViewController) {
         self.accountID = accountID
         self.kind = kind
-        self.mastodonController = mastodonController
+        self.owner = owner
         
-        super.init()
+        super.init(nibName: nil, bundle: nil)
         
-        dragEnabled = true
+        self.controller = TimelineLikeController(delegate: self)
+        
+        mastodonController.persistentContainer.accountSubject
+            .receive(on: DispatchQueue.main)
+            .filter { [unowned self] in $0 == self.accountID }
+            .sink { [unowned self] id in
+                var snapshot = dataSource.snapshot()
+                snapshot.reconfigureItems([.header(id)])
+                dataSource.apply(snapshot, animatingDifferences: true)
+            }
+            .store(in: &cancellables)
+        
+        addKeyCommand(MenuController.refreshCommand(discoverabilityTitle: "Refresh Profile"))
     }
     
     required init?(coder: NSCoder) {
         fatalError("init(coder:) has not been implemented")
     }
     
+    override func loadView() {
+        var config = UICollectionLayoutListConfiguration(appearance: .plain)
+        config.leadingSwipeActionsConfigurationProvider = { [unowned self] in
+            (collectionView.cellForItem(at: $0) as? TimelineStatusCollectionViewCell)?.leadingSwipeActions()
+        }
+        config.trailingSwipeActionsConfigurationProvider = { [unowned self] in
+            (collectionView.cellForItem(at: $0) as? TimelineStatusCollectionViewCell)?.trailingSwipeActions()
+        }
+        config.itemSeparatorHandler = { [unowned self] indexPath, sectionSeparatorConfiguration in
+            guard let item = self.dataSource.itemIdentifier(for: indexPath) else {
+                return sectionSeparatorConfiguration
+            }
+            var config = sectionSeparatorConfiguration
+            if item.hideSeparators {
+                config.topSeparatorVisibility = .hidden
+                config.bottomSeparatorVisibility = .hidden
+            }
+            if case .status(_, _, _) = item {
+                config.topSeparatorInsets = TimelineStatusCollectionViewCell.separatorInsets
+                config.bottomSeparatorInsets = TimelineStatusCollectionViewCell.separatorInsets
+            }
+            return config
+        }
+        let layout = UICollectionViewCompositionalLayout.list(using: config)
+        view = UICollectionView(frame: .zero, collectionViewLayout: layout)
+        collectionView.delegate = self
+        collectionView.dragDelegate = self
+        
+        registerTimelineLikeCells()
+        dataSource = createDataSource()
+        
+        #if !targetEnvironment(macCatalyst)
+        collectionView.refreshControl = UIRefreshControl()
+        collectionView.refreshControl!.addTarget(self, action: #selector(refresh), for: .valueChanged)
+        #endif
+    }
+    
     override func viewDidLoad() {
         super.viewDidLoad()
         
-        tableView.register(UINib(nibName: "TimelineStatusTableViewCell", bundle: .main), forCellReuseIdentifier: "statusCell")
-        
-        // setup the initial snapshot with the sections in the right order, so we don't have to worry about order later
-        var snapshot = Snapshot()
-        snapshot.appendSections([.pinned, .statuses])
-        dataSource.apply(snapshot, animatingDifferences: false)
     }
     
-    func updateUI(account: AccountMO) {
+    private func createDataSource() -> UICollectionViewDiffableDataSource<Section, Item> {
-        if isViewLoaded {
+        collectionView.register(ProfileHeaderCollectionViewCell.self, forCellWithReuseIdentifier: "headerCell")
-            reloadInitial()
+        let statusCell = UICollectionView.CellRegistration<TimelineStatusCollectionViewCell, (String, StatusState, Bool)> { [unowned self] cell, indexPath, item in
-        }
-    }
-    
-    override class func refreshCommandTitle() -> String {
-        return NSLocalizedString("Refresh Statuses", comment: "refresh statuses command discoverability title")
-    }
-    
-    // MARK: - DiffableTimelineLikeTableViewController
-    
-    override func cellProvider(_ tableView: UITableView, _ indexPath: IndexPath, _ item: Item) -> UITableViewCell? {
-        switch item {
-        case .loadingIndicator:
-            return self.loadingIndicatorCell(indexPath: indexPath)
-            
-        case let .status(id: id, state: state, pinned: pinned):
-            let cell = tableView.dequeueReusableCell(withIdentifier: "statusCell", for: indexPath) as! TimelineStatusTableViewCell
             cell.delegate = self
-            cell.showPinned = pinned
+            cell.showPinned = item.2
-            cell.updateUI(statusID: id, state: state)
+            cell.updateUI(statusID: item.0, state: item.1)
-            return cell
+        }
+        return UICollectionViewDiffableDataSource(collectionView: collectionView) { [unowned self] collectionView, indexPath, itemIdentifier in
+            switch itemIdentifier {
+            case .header(let id):
+                if let headerCell = self.headerCell {
+                    return headerCell
+                } else {
+                    let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "headerCell", for: indexPath) as! ProfileHeaderCollectionViewCell
+                    switch self.initialHeaderMode {
+                    case nil:
+                        fatalError("missing initialHeaderMode")
+                    case .createView:
+                        let view = ProfileHeaderView.create()
+                        view.delegate = self.profileHeaderDelegate
+                        view.updateUI(for: id)
+                        view.pagesSegmentedControl.selectedSegmentIndex = self.owner.currentIndex ?? 0
+                        cell.addHeader(view)
+                    case .placeholder(height: let height):
+                        _ = cell.addConstraint(height: height)
+                    }
+                    self.headerCell = cell
+                    return cell
+                }
+            case .status(id: let id, state: let state, pinned: let pinned):
+                return collectionView.dequeueConfiguredReusableCell(using: statusCell, for: indexPath, item: (id, state, pinned))
+            case .loadingIndicator:
+                return loadingIndicatorCell(for: indexPath)
+            case .confirmLoadMore:
+                return confirmLoadMoreCell(for: indexPath)
+            }
         }
     }
     
-    override func loadInitialItems(completion: @escaping (LoadResult) -> Void) {
+    override func viewWillAppear(_ animated: Bool) {
-        guard accountID != nil else {
+        super.viewWillAppear(animated)
-            completion(.failure(.noClient))
+        
+        collectionView.indexPathsForSelectedItems?.forEach {
+            collectionView.deselectItem(at: $0, animated: true)
+        }
+        
+        Task {
+            await load()
+        }
+    }
+    
+    func setAccountID(_ id: String) {
+        self.accountID = id
+        // TODO: maybe this function should be async?
+        Task {
+            await load()
+        }
+    }
+    
+    private func load() async {
+        guard accountID != nil,
+              await controller.state == .notLoadedInitial,
+              isViewLoaded else {
             return
         }
         
-        getStatuses { (response) in
+        var snapshot = NSDiffableDataSourceSnapshot<Section, Item>()
-            guard self.state == .loadingInitial else {
+        snapshot.appendSections([.header, .pinned, .statuses])
-                return
+        snapshot.appendItems([.header(accountID)], toSection: .header)
-            }
+        await apply(snapshot, animatingDifferences: false)
-            
+        print("added header item")
-            switch response {
+        
-            case let .failure(error):
+        await controller.loadInitial()
-                completion(.failure(.client(error)))
+        await tryLoadPinned()
-                
+    }
-            case let .success(statuses, _):
+    
-                if !statuses.isEmpty {
+    private func tryLoadPinned() async {
-                    self.newer = .after(id: statuses.first!.id, count: nil)
+        do {
-                    self.older = .before(id: statuses.last!.id, count: nil)
+            try await loadPinned()
-                }
+        } catch {
-                
+            let config = ToastConfiguration(from: error, with: "Loading Pinned", in: self) { toast in
-                self.mastodonController.persistentContainer.addAll(statuses: statuses) {
+                toast.dismissToast(animated: true)
-                    DispatchQueue.main.async {
+                await self.tryLoadPinned()
-                        var snapshot = self.dataSource.snapshot()
-                        snapshot.appendItems(statuses.map { .status(id: $0.id, state: .unknown, pinned: false) }, toSection: .statuses)
-                        if self.kind == .statuses {
-                            self.loadPinnedStatuses(snapshot: { snapshot }, completion: completion)
-                        } else {
-                            completion(.success(snapshot))
-                        }
-                    }
-                }
             }
+            self.showToast(configuration: config, animated: true)
         }
     }
     
-    private func loadPinnedStatuses(snapshot: @escaping () -> Snapshot, completion: @escaping (LoadResult) -> Void) {
+    private func loadPinned() async throws {
-        guard kind == .statuses,
+        guard case .statuses = kind,
               mastodonController.instanceFeatures.profilePinnedStatuses else {
-            completion(.success(snapshot()))
-            return
-        }
-        getPinnedStatuses { (response) in
-            switch response {
-            case let .failure(error):
-                completion(.failure(.client(error)))
-                
-            case let .success(statuses, _):
-                self.mastodonController.persistentContainer.addAll(statuses: statuses) {
-                    DispatchQueue.main.async {
-                        var snapshot = snapshot()
-                        snapshot.deleteItems(snapshot.itemIdentifiers(inSection: .pinned))
-                        snapshot.appendItems(statuses.map { .status(id: $0.id, state: .unknown, pinned: true) }, toSection: .pinned)
-                        completion(.success(snapshot))
-                    }
-                }
-            }
-        }
-    }
-    
-    override func loadOlderItems(currentSnapshot: @escaping () -> Snapshot, completion: @escaping (LoadResult) -> Void) {
-        guard let older = older else {
-            completion(.failure(.noOlder))
             return
         }
         
-        getStatuses(for: older) { (response) in
-            switch response {
-            case let .failure(error):
-                completion(.failure(.client(error)))
-                
-            case let .success(statuses, _):
-                guard !statuses.isEmpty else {
-                    completion(.failure(.noOlder))
-                    return
-                }
-                
-                self.older = .before(id: statuses.last!.id, count: nil)
-                
-                self.mastodonController.persistentContainer.addAll(statuses: statuses) {
-                    var snapshot = currentSnapshot()
-                    snapshot.appendItems(statuses.map { .status(id: $0.id, state: .unknown, pinned: false) }, toSection: .statuses)
-                    completion(.success(snapshot))
-                }
-            }
-        }
-    }
-   
-    
-    override func loadNewerItems(currentSnapshot: @escaping () -> Snapshot, completion: @escaping (LoadResult) -> Void) {
-        guard let newer = newer else {
-            completion(.failure(.noNewer))
-            return
-        }
-
-        getStatuses(for: newer) { (response) in
-            switch response {
-            case let .failure(error):
-                completion(.failure(.client(error)))
-                
-            case let .success(statuses, _):
-                guard !statuses.isEmpty else {
-                    completion(.failure(.allCaughtUp))
-                    return
-                }
-                
-                self.newer = .after(id: statuses.first!.id, count: nil)
-                
-                self.mastodonController.persistentContainer.addAll(statuses: statuses) {
-                    var snapshot = currentSnapshot()
-                    let items = statuses.map { Item.status(id: $0.id, state: .unknown, pinned: false) }
-                    if let first = snapshot.itemIdentifiers(inSection: .statuses).first {
-                        snapshot.insertItems(items, beforeItem: first)
-                    } else {
-                        snapshot.appendItems(items, toSection: .statuses)
-                    }
-                    completion(.success(snapshot))
-                }
-            }
-        }
-    }
-    
-    private func getStatuses(for range: RequestRange = .default, completion: @escaping Client.Callback<[Status]>) {
-        let request: Request<[Status]>
-        switch kind {
-        case .statuses:
-            request = Account.getStatuses(accountID, range: range, onlyMedia: false, pinned: false, excludeReplies: true)
-        case .withReplies:
-            request = Account.getStatuses(accountID, range: range, onlyMedia: false, pinned: false, excludeReplies: false)
-        case .onlyMedia:
-            request = Account.getStatuses(accountID, range: range, onlyMedia: true, pinned: false, excludeReplies: false)
-        }
-        mastodonController.run(request, completion: completion)
-    }
-    
-    private func getPinnedStatuses(completion: @escaping Client.Callback<[Status]>) {
         let request = Account.getStatuses(accountID, range: .default, onlyMedia: false, pinned: true, excludeReplies: false)
-        mastodonController.run(request, completion: completion)
+        let (statuses, _) = try await mastodonController.run(request)
+        
+        await withCheckedContinuation { continuation in
+            mastodonController.persistentContainer.addAll(statuses: statuses) {
+                continuation.resume()
+            }
+        }
+        
+        var snapshot = dataSource.snapshot()
+        let items = statuses.map { Item.status(id: $0.id, state: .unknown, pinned: true) }
+        snapshot.appendItems(items, toSection: .pinned)
+        await apply(snapshot, animatingDifferences: true)
     }
     
-    override func refresh() {
+    @objc func refresh() {
-        super.refresh()
+        Task {
-        
+            // TODO: coalesce these data source updates
-        // only refresh pinned if the super call actually succeded (put the state into .loadingNewer)
+            // TODO: refresh profile
-        if state == .loadingNewer,
+            await controller.loadNewer()
-           kind == .statuses {
+            await tryLoadPinned()
-            loadPinnedStatuses(snapshot: dataSource.snapshot) { (result) in
+            #if !targetEnvironment(macCatalyst)
-                switch result {
+            collectionView.refreshControl?.endRefreshing()
-                case .failure(_):
+            #endif
-                    break
-                    
-                case let .success(snapshot):
-                    DispatchQueue.main.async {
-                        self.dataSource.apply(snapshot)
-                    }
-                }
-            }
         }
     }
     
@@ -239,26 +227,200 @@ extension ProfileStatusesViewController {
     enum Kind {
         case statuses, withReplies, onlyMedia
     }
+    enum HeaderMode {
+        case createView, placeholder(height: CGFloat)
+    }
 }
 
 extension ProfileStatusesViewController {
-    enum Section: DiffableTimelineLikeSection {
+    enum Section: TimelineLikeCollectionViewSection {
-        case loadingIndicator
+        case header
         case pinned
         case statuses
-    }
+        case footer
-    enum Item: DiffableTimelineLikeItem {
-        case loadingIndicator
-        case status(id: String, state: StatusState, pinned: Bool)
         
-        var id: String? {
+        static var entries: Self { .statuses }
-            switch self {
+    }
-            case .loadingIndicator:
+    enum Item: TimelineLikeCollectionViewItem {
-                return nil
+        typealias TimelineItem = String
-            case .status(id: let id, state: _, pinned: _):
+        
-                return id
+        case header(String)
+        case status(id: String, state: StatusState, pinned: Bool)
+        case loadingIndicator
+        case confirmLoadMore
+        
+        static func fromTimelineItem(_ item: String) -> Self {
+            return .status(id: item, state: .unknown, pinned: false)
+        }
+        
+        static func ==(lhs: Item, rhs: Item) -> Bool {
+            switch (lhs, rhs) {
+            case let (.header(a), .header(b)):
+                return a == b
+            case let (.status(id: a, state: _, pinned: ap), .status(id: b, state: _, pinned: bp)):
+                return a == b && ap == bp
+            case (.loadingIndicator, .loadingIndicator):
+                return true
+            case (.confirmLoadMore, .confirmLoadMore):
+                return true
+            default:
+                return false
             }
         }
+        
+        func hash(into hasher: inout Hasher) {
+            switch self {
+            case .header(let id):
+                hasher.combine(0)
+                hasher.combine(id)
+            case .status(id: let id, state: _, pinned: let pinned):
+                hasher.combine(1)
+                hasher.combine(id)
+                hasher.combine(pinned)
+            case .loadingIndicator:
+                hasher.combine(2)
+            case .confirmLoadMore:
+                hasher.combine(3)
+            }
+        }
+        
+        var hideSeparators: Bool {
+            switch self {
+            case .loadingIndicator, .confirmLoadMore:
+                return true
+            default:
+                return false
+            }
+        }
+        
+        var isSelectable: Bool {
+            switch self {
+            case .status(id: _, state: _, pinned: _):
+                return true
+            default:
+                return false
+            }
+        }
+    }
+}
+
+extension ProfileStatusesViewController: TimelineLikeControllerDelegate {
+    typealias TimelineItem = String // status ID
+    
+    private func request(for range: RequestRange = .default) -> Request<[Status]> {
+        switch kind {
+        case .statuses:
+            return Account.getStatuses(accountID, range: range, onlyMedia: false, pinned: false, excludeReplies: true)
+        case .withReplies:
+            return Account.getStatuses(accountID, range: range, onlyMedia: false, pinned: false, excludeReplies: false)
+        case .onlyMedia:
+            return Account.getStatuses(accountID, range: range, onlyMedia: true, pinned: false, excludeReplies: false)
+        }
+    }
+    
+    func loadInitial() async throws -> [String] {
+        let request = request()
+        let (statuses, _) = try await mastodonController.run(request)
+        
+        if !statuses.isEmpty {
+            newer = .after(id: statuses.first!.id, count: nil)
+            older = .before(id: statuses.last!.id, count: nil)
+        }
+        
+        return await withCheckedContinuation { continuation in
+            mastodonController.persistentContainer.addAll(statuses: statuses) {
+                continuation.resume(returning: statuses.map(\.id))
+            }
+        }
+    }
+    
+    func loadNewer() async throws -> [String] {
+        guard let newer else {
+            throw Error.noNewer
+        }
+        
+        let request = request(for: newer)
+        let (statuses, _) = try await mastodonController.run(request)
+        
+        guard !statuses.isEmpty else {
+            throw Error.allCaughtUp
+        }
+        
+        self.newer = .after(id: statuses.first!.id, count: nil)
+        
+        return await withCheckedContinuation { continuation in
+            mastodonController.persistentContainer.addAll(statuses: statuses) {
+                continuation.resume(returning: statuses.map(\.id))
+            }
+        }
+    }
+    
+    func loadOlder() async throws -> [String] {
+        guard let older else {
+            throw Error.noOlder
+        }
+        
+        let request = request(for: older)
+        let (statuses, _) = try await mastodonController.run(request)
+        
+        guard !statuses.isEmpty else {
+            return []
+        }
+        
+        self.older = .before(id: statuses.last!.id, count: nil)
+        
+        return await withCheckedContinuation { continuation in
+            mastodonController.persistentContainer.addAll(statuses: statuses) {
+                continuation.resume(returning: statuses.map(\.id))
+            }
+        }
+    }
+    
+    enum Error: TimelineLikeCollectionViewError {
+        case noNewer
+        case noOlder
+        case allCaughtUp
+    }
+}
+
+extension ProfileStatusesViewController: UICollectionViewDelegate {
+    func collectionView(_ collectionView: UICollectionView, willDisplay cell: UICollectionViewCell, forItemAt indexPath: IndexPath) {
+        guard case .statuses = dataSource.sectionIdentifier(for: indexPath.section) else {
+            return
+        }
+        
+        let itemsInSection = collectionView.numberOfItems(inSection: indexPath.section)
+        if indexPath.row == itemsInSection - 1 {
+            Task {
+                await controller.loadOlder()
+            }
+        }
+    }
+    
+    func collectionView(_ collectionView: UICollectionView, shouldSelectItemAt indexPath: IndexPath) -> Bool {
+        return dataSource.itemIdentifier(for: indexPath)?.isSelectable ?? false
+    }
+    
+    func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
+        guard case .status(id: let id, state: let state, pinned: _) = dataSource.itemIdentifier(for: indexPath) else {
+            return
+        }
+        let status = mastodonController.persistentContainer.status(for: id)!
+        selected(status: status.reblog?.id ?? id, state: state.copy())
+    }
+    
+    func collectionView(_ collectionView: UICollectionView, contextMenuConfigurationForItemAt indexPath: IndexPath, point: CGPoint) -> UIContextMenuConfiguration? {
+        return (collectionView.cellForItem(at: indexPath) as? TimelineStatusCollectionViewCell)?.contextMenuConfiguration()
+    }
+    
+    func collectionView(_ collectionView: UICollectionView, willPerformPreviewActionForMenuWith configuration: UIContextMenuConfiguration, animator: UIContextMenuInteractionCommitAnimating) {
+        MenuPreviewHelper.willPerformPreviewAction(animator: animator, presenter: self)
+    }
+}
+
+extension ProfileStatusesViewController: UICollectionViewDragDelegate {
+    func collectionView(_ collectionView: UICollectionView, itemsForBeginning session: UIDragSession, at indexPath: IndexPath) -> [UIDragItem] {
+        (collectionView.cellForItem(at: indexPath) as? TimelineStatusCollectionViewCell)?.dragItemsForBeginning(session: session) ?? []
     }
 }
 
@@ -266,23 +428,15 @@ extension ProfileStatusesViewController: TuskerNavigationDelegate {
     var apiController: MastodonController { mastodonController }
 }
 
-extension ProfileStatusesViewController: StatusTableViewCellDelegate {
+extension ProfileStatusesViewController: MenuActionProvider {
-    func statusCellCollapsedStateChanged(_ cell: BaseStatusTableViewCell) {
+}
-        if #available(iOS 16.0, *) {
+
-        } else {
+extension ProfileStatusesViewController: StatusCollectionViewCellDelegate {
-            cellHeightChanged()
+    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: false, completion: completion)
         }
     }
 }
-
-extension ProfileStatusesViewController: UITableViewDataSourcePrefetching, StatusTablePrefetching {
-    func tableView(_ tableView: UITableView, prefetchRowsAt indexPaths: [IndexPath]) {
-        let ids = indexPaths.compactMap { dataSource.itemIdentifier(for: $0)?.id }
-        prefetchStatuses(with: ids)
-    }
-    
-    func tableView(_ tableView: UITableView, cancelPrefetchingForRowsAt indexPaths: [IndexPath]) {
-        let ids = indexPaths.compactMap { dataSource.itemIdentifier(for: $0)?.id }
-        cancelPrefetchingStatuses(with: ids)
-    }
-}

Tusker/Screens/Profile/ProfileViewController.swift

@@ -2,8 +2,8 @@
 //  ProfileViewController.swift
 //  Tusker
 //
-//  Created by Shadowfacts on 7/3/20.
+//  Created by Shadowfacts on 10/10/22.
-//  Copyright © 2020 Shadowfacts. All rights reserved.
+//  Copyright © 2022 Shadowfacts. All rights reserved.
 //
 
 import UIKit
@@ -18,39 +18,43 @@ class ProfileViewController: UIPageViewController {
     // when first constructed. It should never be set to nil.
     var accountID: String? {
         willSet {
-            if newValue == nil {
+            precondition(newValue != nil, "Do not set ProfileViewController.accountID to nil")
-                fatalError("Do not set ProfileViewController.accountID to nil")
-            }
         }
         didSet {
-            pageControllers.forEach { $0.accountID = accountID }
+            pageControllers.forEach { $0.setAccountID(accountID!) }
-            loadAccount()
+            Task {
+                await loadAccount()
+            }
         }
     }
 
-    private var accountUpdater: Cancellable?
-    
     private(set) var currentIndex: Int!
-    let pageControllers: [ProfileStatusesViewController]
+    private var pageControllers: [ProfileStatusesViewController]!
     var currentViewController: ProfileStatusesViewController {
         pageControllers[currentIndex]
     }
     
-    private var headerView: ProfileHeaderView!
+    private var state: State = .idle
     
-    private var hasAppeared = false
+    private var cancellables = Set<AnyCancellable>()
     
     init(accountID: String?, mastodonController: MastodonController) {
         self.accountID = accountID
         self.mastodonController = mastodonController
         
+        super.init(transitionStyle: .scroll, navigationOrientation: .horizontal, options: nil)
+        
         self.pageControllers = [
-            ProfileStatusesViewController(accountID: accountID, kind: .statuses, mastodonController: mastodonController),
+            .init(accountID: accountID, kind: .statuses, owner: self),
-            ProfileStatusesViewController(accountID: accountID, kind: .withReplies, mastodonController: mastodonController),
+            .init(accountID: accountID, kind: .withReplies, owner: self),
-            ProfileStatusesViewController(accountID: accountID, kind: .onlyMedia, mastodonController: mastodonController)
+            .init(accountID: accountID, kind: .onlyMedia, owner: self),
         ]
         
-        super.init(transitionStyle: .scroll, navigationOrientation: .horizontal, options: nil)
+        // try to update the account UI immediately if possible, to avoid the navigation title popping in later
+        if let accountID,
+           let account = mastodonController.persistentContainer.account(for: accountID) {
+            updateAccountUI(account: account)
+        }
     }
     
     required init?(coder: NSCoder) {
@@ -62,35 +66,36 @@ class ProfileViewController: UIPageViewController {
 
         view.backgroundColor = .systemBackground
         
+        for pageController in pageControllers {
+            pageController.profileHeaderDelegate = self
+        }
+        
+        selectPage(at: 0, animated: false)
+        
         let composeButton = UIBarButtonItem(barButtonSystemItem: .compose, target: self, action: #selector(composeMentioning))
-        composeButton.menu = UIMenu(title: "", image: nil, identifier: nil, options: [], children: [
+        composeButton.menu = UIMenu(children: [
-            UIAction(title: "Direct Message", image: UIImage(systemName: Status.Visibility.direct.unfilledImageName), identifier: nil, discoverabilityTitle: nil, attributes: [], state: .off, handler: { [weak self] (_) in
+            UIAction(title: "Direct Message", image: UIImage(systemName: Status.Visibility.direct.unfilledImageName), handler: { [unowned self] _ in
-                self?.composeDirectMentioning()
+                self.composeDirectMentioning()
             })
         ])
         composeButton.isEnabled = mastodonController.loggedIn
         navigationItem.rightBarButtonItem = composeButton
         
-        headerView = ProfileHeaderView.create()
-        headerView.delegate = self
-
-        selectPage(at: 0, animated: false)
-        
-        currentViewController.tableView.tableHeaderView = headerView
-        
-        NSLayoutConstraint.activate([
-            headerView.widthAnchor.constraint(equalTo: view.widthAnchor),
-        ])
-        
         addKeyCommand(MenuController.prevSubTabCommand)
         addKeyCommand(MenuController.nextSubTabCommand)
         
-        accountUpdater = mastodonController.persistentContainer.accountSubject
+        mastodonController.persistentContainer.accountSubject
             .receive(on: DispatchQueue.main)
-            .filter { [weak self] in $0 == self?.accountID }
+            .filter { [unowned self] in $0 == self.accountID }
-            .sink { [weak self] (_) in self?.updateAccountUI() }
+            .sink { [unowned self] id in
+                let account = self.mastodonController.persistentContainer.account(for: id)!
+                self.updateAccountUI(account: account)
+            }
+            .store(in: &cancellables)
         
-        loadAccount()
+        Task {
+            await loadAccount()
+        }
         
         // disable the transparent nav bar because it gets messy with multiple pages at different scroll positions
         if let nav = navigationController {
@@ -100,168 +105,192 @@ class ProfileViewController: UIPageViewController {
         }
     }
     
-    override func viewDidAppear(_ animated: Bool) {
+    private func loadAccount() async {
-        super.viewDidAppear(animated)
+        guard let accountID else {
-        
-        hasAppeared = true
-    }
-    
-    private func loadAccount() {
-        guard let accountID = accountID else { return }
-        if mastodonController.persistentContainer.account(for: accountID) != nil {
-            updateAccountUI()
-        } else {
-            let req = Client.getAccount(id: accountID)
-            mastodonController.run(req) { [weak self] (response) in
-                guard let self = self else { return }
-                switch response {
-                case .success(let account, _):
-                    self.mastodonController.persistentContainer.addOrUpdate(account: account) { (account) in
-                        DispatchQueue.main.async {
-                            self.updateAccountUI()
-                        }
-                    }
-                    
-                case .failure(let error):
-                    DispatchQueue.main.async {
-                        let config = ToastConfiguration(from: error, with: "Loading", in: self) { [unowned self] (toast) in
-                            toast.dismissToast(animated: true)
-                            self.loadAccount()
-                        }
-                        self.showToast(configuration: config, animated: true)
-                    }
-                }
-            }
-        }
-    }
-    
-    private func updateAccountUI() {
-        guard let accountID = accountID,
-              let account = mastodonController.persistentContainer.account(for: accountID) else {
             return
         }
-        
+        if let account = mastodonController.persistentContainer.account(for: accountID) {
-        if let currentAccountID = mastodonController.accountInfo?.id {
+            updateAccountUI(account: account)
-            userActivity = UserActivityManager.showProfileActivity(id: accountID, accountID: currentAccountID)
+        } else {
-        }
+            do {
-        
+                let req = Client.getAccount(id: accountID)
-        // Optionally invoke updateUI on headerView because viewDidLoad may not have been called yet
+                let (account, _) = try await mastodonController.run(req)
-        headerView?.updateUI(for: accountID)
+                let mo = await withCheckedContinuation { continuation in
-        navigationItem.title = account.displayNameWithoutCustomEmoji
+                    mastodonController.persistentContainer.addOrUpdate(account: account) { (mo) in
-        
+                        continuation.resume(returning: mo)
-        // Only call updateUI on the individual page controllers if the account is loaded after the profile VC has appeared on screen.
+                    }
-        // Otherwise, fi the page view controllers do something with the table view before they appear, the table view doesn't load
+                }
-        // its cells until the user begins to scroll.
+                self.updateAccountUI(account: mo)
-        if hasAppeared {
+            } catch {
-            pageControllers.forEach {
+                let config = ToastConfiguration(from: error, with: "Loading Account", in: self) { [unowned self] toast in
-                $0.updateUI(account: account)
+                    toast.dismissToast(animated: true)
+                    await self.loadAccount()
+                }
+                self.showToast(configuration: config, animated: true)
             }
         }
     }
     
+    private func updateAccountUI(account: AccountMO) {
+        if let currentAccountID = mastodonController.accountInfo?.id {
+            userActivity = UserActivityManager.showProfileActivity(id: account.id, accountID: currentAccountID)
+        }
+        
+        navigationItem.title = account.displayNameWithoutCustomEmoji
+    }
+    
     private func selectPage(at index: Int, animated: Bool, completion: ((Bool) -> Void)? = nil) {
-        let direction: UIPageViewController.NavigationDirection = currentIndex == nil || index - currentIndex > 0 ? .forward : .reverse
+        guard case .idle = state else {
-        currentIndex = index
+            return
+        }
         
-        headerView.pagesSegmentedControl.selectedSegmentIndex = index
+        state = .animating
+        
+        let direction: UIPageViewController.NavigationDirection
+        if currentIndex == nil || index - currentIndex > 0 {
+            direction = .forward
+        } else {
+            direction = .reverse
+        }
         
         guard let old = viewControllers?.first as? ProfileStatusesViewController else {
             // if old doesn't exist, we're selecting the initial view controller, so moving the header around isn't necessary
-            // since it will be added in viewDidLoad
+            pageControllers[index].initialHeaderMode = .createView
-            setViewControllers([pageControllers[index]], direction: direction, animated: animated, completion: completion)
+            setViewControllers([pageControllers[index]], direction: direction, animated: animated) { finished in
+                self.state = .idle
+                completion?(finished)
+            }
+            currentIndex = index
             return
         }
         let new = pageControllers[index]
         
-        let headerHeight = self.headerView.bounds.height
+        currentIndex = index
         
-        // Store old's content offset so it can be transferred to new
+        // TODO: old.headerCell could be nil if scrolled down and key command used
-        let prevOldContentOffset = old.tableView.contentOffset
+        let oldHeaderCell = old.headerCell!
-        // Remove the header, inset the table content by the same amount, and adjust the offset so the cells don't move
-        old.tableView.tableHeaderView = nil
-        old.tableView.contentInset = UIEdgeInsets(top: headerHeight, left: 0, bottom: 0, right: 0)
-        old.tableView.contentOffset.y -= headerHeight
         
-        // Add the header to ourself temporarily, and constrain it to the same position it was in
+        // old header cell must have the header view
-        self.view.addSubview(self.headerView)
+        let headerView = oldHeaderCell.addConstraint(height: oldHeaderCell.bounds.height)!
-        let tempTopConstraint = self.headerView.topAnchor.constraint(equalTo: self.view.topAnchor, constant: -(prevOldContentOffset.y + old.tableView.safeAreaInsets.top))
+        
+        if new.isViewLoaded {
+            _ = new.headerCell!.addConstraint(height: oldHeaderCell.bounds.height)
+        } else {
+            new.initialHeaderMode = .placeholder(height: oldHeaderCell.bounds.height)
+        }
+        
+        // disable user interaction during animation, to avoid any potential weird race conditions
+        headerView.isUserInteractionEnabled = false
+        headerView.layer.zPosition = 100
+        view.addSubview(headerView)
+        let oldHeaderCellTop = oldHeaderCell.convert(CGPoint.zero, to: view).y
+        // TODO: use safe area layout guide instead of manually adjusting this?
+        let headerTopOffset = oldHeaderCellTop - view.safeAreaInsets.top
         NSLayoutConstraint.activate([
-            self.headerView.widthAnchor.constraint(equalTo: self.view.widthAnchor),
+            headerView.topAnchor.constraint(equalTo: view.topAnchor, constant: headerTopOffset),
-            tempTopConstraint
+            headerView.leadingAnchor.constraint(equalTo: view.safeAreaLayoutGuide.leadingAnchor),
+            headerView.trailingAnchor.constraint(equalTo: view.safeAreaLayoutGuide.trailingAnchor),
         ])
         
-        // Setup the inset in new, in case it hasn't been already
+        // hide scroll indicators during the transition because otherwise the show through the
-        new.tableView.contentInset = UIEdgeInsets(top: headerHeight, left: 0, bottom: 0, right: 0)
+        // profile header, even though it has an opaque background
-        // Match the scroll positions
+        old.collectionView.showsVerticalScrollIndicator = false
-        new.tableView.contentOffset = old.tableView.contentOffset
+        if new.isViewLoaded {
+            new.collectionView.showsVerticalScrollIndicator = false
+        }
         
-        // Actually switch pages
+        // if the new view isn't loaded or it isn't tall enough to match content offsets, animate scrolling old back to top to match new
-        setViewControllers([pageControllers[index]], direction: direction, animated: animated) { (finished) in
+        if animated,
-            // Defer everything one run-loop iteration, otherwise altering the tableView's contentInset/Offset causes it to jump around during the animation
+           !new.isViewLoaded || new.collectionView.contentSize.height - new.collectionView.bounds.height < old.collectionView.contentOffset.y {
-            DispatchQueue.main.async {
+            // We need to display a snapshot over the old view because setting the content offset to the top w/o animating
-                // Move the header to the new table view
+            // results in the collection view immediately removing cells that will be offscreen.
-                new.tableView.tableHeaderView = self.headerView
+            // And we can't just call setContentOffset(_:animated:) because its animation curve does not match ours/the page views
-                // Remove the inset, and set the offset back to old's original one, prior to removing the header
+            // So, we capture a snapshot before the content offset is changed, so those cells can be shown during the animation,
-                new.tableView.contentInset = .zero
+            // rather than a gap appearing during it.
-                new.tableView.contentOffset = prevOldContentOffset
+            let snapshot = old.collectionView.snapshotView(afterScreenUpdates: true)!
+            let origOldContentOffset = old.collectionView.contentOffset
+            old.collectionView.contentOffset = CGPoint(x: 0, y: view.safeAreaInsets.top)
             
-                // Deactivate the top constraint, otherwise it sticks around
+            snapshot.frame = old.collectionView.bounds
-                tempTopConstraint.isActive = false
+            snapshot.frame.origin.y = 0
-                // Re-add the width constraint since it was removed by re-parenting the view
+            snapshot.layer.zPosition = 99
-                // Why was the width constraint removed, but the top one not? Good question, I have no idea.
+            view.addSubview(snapshot)
-                NSLayoutConstraint.activate([
-                    self.headerView.widthAnchor.constraint(equalTo: self.view.widthAnchor)
-                ])
             
-                // Layout and update the table view, otherwise the content jumps around when first scrolling it,
+            // empirically, 0.3s seems to match the UIPageViewController animation
-                // if old was not scrolled all the way to the top
+            UIView.animate(withDuration: 0.3, delay: 0, options: .curveEaseInOut) {
-                new.tableView.layoutIfNeeded()
+                // animate the snapshot offscreen in the same direction as the old view
-                let snapshot = new.dataSource.snapshot()
+                snapshot.frame.origin.x = direction == .forward ? -self.view.bounds.width : self.view.bounds.width
-                new.dataSource.apply(snapshot, animatingDifferences: false)
+                // animate the snapshot to be "scrolled" to top
-                
+                snapshot.frame.origin.y = self.view.safeAreaInsets.top + origOldContentOffset.y
-                completion?(finished)
+                // if scrolling because the new collection view's content isn't tall enough, make sure to scroll it to top as well
+                if new.isViewLoaded {
+                    new.collectionView.contentOffset = CGPoint(x: 0, y: -self.view.safeAreaInsets.top)
+                }
+                headerView.transform = CGAffineTransform(translationX: 0, y: -headerTopOffset)
+            } completion: { _ in
+                snapshot.removeFromSuperview()
             }
+        } else if new.isViewLoaded {
+            new.collectionView.contentOffset = old.collectionView.contentOffset
+        }
+        
+        setViewControllers([pageControllers[index]], direction: direction, animated: animated) { finished in
+            // reenable scroll indicators after the switching animation is done
+            old.collectionView.showsVerticalScrollIndicator = true
+            new.collectionView.showsVerticalScrollIndicator = true
+            
+            headerView.isUserInteractionEnabled = true
+            
+            headerView.transform = .identity
+            headerView.layer.zPosition = 0
+            // move the header view into the new page controller's cell
+            // new's headerCell should always be non-nil, because the account must be loaded (in order to have triggered this switch), and so new should add the cell immediately on load
+            new.headerCell!.addHeader(headerView)
+            
+            self.state = .idle
+            completion?(finished)
         }
     }
     
     // MARK: Interaction
     
     @objc private func composeMentioning() {
-        if let accountID = accountID,
+        if let accountID,
            let account = mastodonController.persistentContainer.account(for: accountID) {
             compose(mentioningAcct: account.acct)
         }
     }
     
     private func composeDirectMentioning() {
-        if let accountID = accountID,
+        if let accountID,
            let account = mastodonController.persistentContainer.account(for: accountID) {
             let draft = mastodonController.createDraft(mentioningAcct: account.acct)
             draft.visibility = .direct
             compose(editing: draft)
         }
     }
+}
 
+extension ProfileViewController {
+    enum State {
+        case idle
+        case animating
+    }
 }
 
 extension ProfileViewController: TuskerNavigationDelegate {
     var apiController: MastodonController { mastodonController }
 }
 
-extension ProfileViewController: ProfileHeaderViewDelegate {
+extension ProfileViewController: ToastableViewController {
-    func profileHeader(_ view: ProfileHeaderView, selectedPostsIndexChangedTo newIndex: Int) {
-        // disable user interaction on segmented control while switching pages to prevent
-        // race condition from trying to switch to multiple pages simultaneously
-        view.pagesSegmentedControl.isUserInteractionEnabled = false
-        selectPage(at: newIndex, animated: true) { (finished) in
-            view.pagesSegmentedControl.isUserInteractionEnabled = true
-        }
-    }
 }
 
-extension ProfileViewController: TabBarScrollableViewController {
+extension ProfileViewController: ProfileHeaderViewDelegate {
-    func tabBarScrollToTop() {
+    func profileHeader(_ headerView: ProfileHeaderView, selectedPostsIndexChangedTo newIndex: Int) {
-        pageControllers[currentIndex].tabBarScrollToTop()
+        guard case .idle = state else {
+            return
+        }
+        selectPage(at: newIndex, animated: true)
     }
 }
 
@@ -276,6 +305,3 @@ extension ProfileViewController: TabbedPageViewController {
         selectPage(at: currentIndex - 1, animated: true)
     }
 }
-
-extension ProfileViewController: ToastableViewController {
-}

Tusker/Screens/Timeline/TimelineViewController.swift

@@ -61,8 +61,8 @@ class TimelineViewController: UIViewController, TimelineLikeCollectionViewContro
                 config.bottomSeparatorVisibility = .hidden
             }
             if case .status(_, _) = item {
-                config.topSeparatorInsets = NSDirectionalEdgeInsets(top: 0, leading: 16, bottom: 0, trailing: 0)
+                config.topSeparatorInsets = TimelineStatusCollectionViewCell.separatorInsets
-                config.bottomSeparatorInsets = NSDirectionalEdgeInsets(top: 0, leading: 16, bottom: 0, trailing: 0)
+                config.bottomSeparatorInsets = TimelineStatusCollectionViewCell.separatorInsets
             }
             return config
         }
@@ -87,14 +87,9 @@ class TimelineViewController: UIViewController, TimelineLikeCollectionViewContro
     }
     
     private func createDataSource() -> UICollectionViewDiffableDataSource<Section, Item> {
-        let statusCell = UICollectionView.CellRegistration<TimelineStatusCollectionViewCell, Item> { [unowned self] cell, indexPath, item in
+        let statusCell = UICollectionView.CellRegistration<TimelineStatusCollectionViewCell, (String, StatusState)> { [unowned self] cell, indexPath, item in
-            guard case .status(id: let id, state: let state) = item,
-                  let status = mastodonController.persistentContainer.status(for: id) else {
-                fatalError()
-            }
-            cell.mastodonController = mastodonController
             cell.delegate = self
-            cell.updateUI(statusID: id, state: state)
+            cell.updateUI(statusID: item.0, state: item.1)
         }
         let timelineDescriptionCell = UICollectionView.CellRegistration<PublicTimelineDescriptionCollectionViewCell, Item> { [unowned self] cell, indexPath, item in
             guard case .public(let local) = timeline else {
@@ -108,8 +103,8 @@ class TimelineViewController: UIViewController, TimelineLikeCollectionViewContro
         }
         return UICollectionViewDiffableDataSource(collectionView: collectionView) { [unowned self] collectionView, indexPath, itemIdentifier in
             switch itemIdentifier {
-            case .status(_, _):
+            case .status(id: let id, state: let state):
-                return collectionView.dequeueConfiguredReusableCell(using: statusCell, for: indexPath, item: itemIdentifier)
+                return collectionView.dequeueConfiguredReusableCell(using: statusCell, for: indexPath, item: (id, state))
             case .loadingIndicator:
                 return loadingIndicatorCell(for: indexPath)
             case .confirmLoadMore:
@@ -255,7 +250,7 @@ extension TimelineViewController {
         
         var hideSeparators: Bool {
             switch self {
-            case .loadingIndicator, .publicTimelineDescription:
+            case .loadingIndicator, .publicTimelineDescription, .confirmLoadMore:
                 return true
             default:
                 return false
@@ -326,10 +321,12 @@ extension TimelineViewController {
         let request = Client.getStatuses(timeline: timeline, range: older)
         let (statuses, _) = try await mastodonController.run(request)
         
-        if !statuses.isEmpty {
+        guard !statuses.isEmpty else {
-            self.older = .before(id: statuses.last!.id, count: nil)
+            return []
         }
         
+        self.older = .before(id: statuses.last!.id, count: nil)
+        
         return await withCheckedContinuation { continuation in
             mastodonController.persistentContainer.addAll(statuses: statuses) {
                 continuation.resume(returning: statuses.map(\.id))
@@ -347,8 +344,7 @@ extension TimelineViewController {
 
 extension TimelineViewController: UICollectionViewDelegate {
     func collectionView(_ collectionView: UICollectionView, willDisplay cell: UICollectionViewCell, forItemAt indexPath: IndexPath) {
-        guard case .statuses = dataSource.sectionIdentifier(for: indexPath.section),
+        guard case .statuses = dataSource.sectionIdentifier(for: indexPath.section) else {
-              case .status(_, _) = dataSource.itemIdentifier(for: indexPath) else {
             return
         }
         

Tusker/Screens/Utilities/SplitNavigationController.swift

@@ -271,7 +271,8 @@ private class SplitSecondaryNavigationController: EnhancedNavigationViewControll
     override var next: UIResponder? {
         // ordinarily, the next responder in the chain would be the SplitNavigationController's view
         // but that would bypass the VC in the root nav, so we reroute the repsonder chain to include it
-        owner.viewControllers.first!.view
+        // first seems to be nil when using the view debugger for some reason, so in that case, defer to super
+        owner.viewControllers.first?.view ?? super.next
     }
     
     private func configureSecondarySplitCloseButton(for viewController: UIViewController) {

Tusker/TuskerNavigationDelegate.swift

@@ -28,7 +28,7 @@ extension TuskerNavigationDelegate {
     
     func selected(account accountID: String) {
         // don't open if the account is the same as the current one
-        if let profileController = self as? ProfileViewController,
+        if let profileController = self as? ProfileStatusesViewController,
             profileController.accountID == accountID {
             return
         }

Tusker/Views/Status/StatusCollectionViewCell.swift

@@ -29,8 +29,6 @@ protocol StatusCollectionViewCell: UICollectionViewCell, AttachmentViewDelegate
     var reblogButton: UIButton { get }
     var moreButton: UIButton { get }
     
-    // TODO: why is one of these ! and the other ?
-    var mastodonController: MastodonController! { get }
     var delegate: StatusCollectionViewCellDelegate? { get }
     
     var showStatusAutomatically: Bool { get }
@@ -50,6 +48,8 @@ protocol StatusCollectionViewCell: UICollectionViewCell, AttachmentViewDelegate
 extension StatusCollectionViewCell {
     static var avatarImageViewSize: CGFloat { 50 }
     
+    var mastodonController: MastodonController! { delegate?.apiController }
+    
     func baseCreateObservers() {
         mastodonController.persistentContainer.statusSubject
             .receive(on: DispatchQueue.main)

Tusker/Views/Status/TimelineStatusCollectionViewCell.swift

@@ -12,6 +12,8 @@ import Combine
 
 class TimelineStatusCollectionViewCell: UICollectionViewListCell, StatusCollectionViewCell {
     
+    static let separatorInsets = NSDirectionalEdgeInsets(top: 0, leading: 16, bottom: 0, trailing: 0)
+    
     // MARK: Subviews
     
     private lazy var reblogLabel = EmojiLabel().configure {
@@ -216,7 +218,6 @@ class TimelineStatusCollectionViewCell: UICollectionViewListCell, StatusCollecti
     private var mainContainerBottomToActionsConstraint: NSLayoutConstraint!
     private var mainContainerBottomToSelfConstraint: NSLayoutConstraint!
     
-    weak var mastodonController: MastodonController!
     weak var delegate: StatusCollectionViewCellDelegate?
     var showStatusAutomatically: Bool {
         // TODO: needed once conversation controller refactored
@@ -226,10 +227,7 @@ class TimelineStatusCollectionViewCell: UICollectionViewListCell, StatusCollecti
         // TODO: needed once conversation controller refactored
         true
     }
-    var showPinned: Bool {
+    var showPinned: Bool = false
-        // TODO: needed once profile controller refactored
-        false
-    }
     
     // alas these need to be internal so they're accessible from the protocol extensions
     var statusID: String!