State restoration for presented and edited drafts

Closes #270

Packages/Duckable/Sources/Duckable/API.swift

@@ -29,11 +29,11 @@ public protocol DuckableViewControllerDelegate: AnyObject {
 
 extension UIViewController {
     @available(iOS 16.0, *)
-    public func presentDuckable(_ viewController: DuckableViewController) -> Bool {
+    public func presentDuckable(_ viewController: DuckableViewController, animated: Bool, isDucked: Bool = false) -> Bool {
         var cur: UIViewController? = self
         while let vc = cur {
             if let container = vc as? DuckableContainerViewController {
-                container.presentDuckable(viewController, animated: true, completion: nil)
+                container.presentDuckable(viewController, animated: animated, isDucked: isDucked, completion: nil)
                 return true
             } else {
                 cur = vc.parent

Packages/Duckable/Sources/Duckable/DuckableContainerViewController.swift

@@ -17,6 +17,14 @@ public class DuckableContainerViewController: UIViewController, DuckableViewCont
     private var bottomConstraint: NSLayoutConstraint!
     private(set) var state = State.idle
     
+    public var duckedViewController: DuckableViewController? {
+        if case .ducked(let vc, placeholder: _) = state {
+            return vc
+        } else {
+            return nil
+        }
+    }
+    
     public init(child: UIViewController) {
         self.child = child
         
@@ -50,7 +58,7 @@ public class DuckableContainerViewController: UIViewController, DuckableViewCont
         ])
     }
     
-    func presentDuckable(_ viewController: DuckableViewController, animated: Bool, completion: (() -> Void)?) {
+    func presentDuckable(_ viewController: DuckableViewController, animated: Bool, isDucked: Bool, completion: (() -> Void)?) {
         guard case .idle = state else {
             if animated,
                case .ducked(_, placeholder: let placeholder) = state {
@@ -69,8 +77,13 @@ public class DuckableContainerViewController: UIViewController, DuckableViewCont
             }
             return
         }
-        state = .presentingDucked(viewController, isFirstPresentation: true)
+        if isDucked {
-        doPresentDuckable(viewController, animated: animated, completion: completion)
+            state = .ducked(viewController, placeholder: createPlaceholderForDuckedViewController(viewController))
+            configureChildForDuckedPlaceholder()
+        } else {
+            state = .presentingDucked(viewController, isFirstPresentation: true)
+            doPresentDuckable(viewController, animated: animated, completion: completion)
+        }
     }
     
     private func doPresentDuckable(_ viewController: DuckableViewController, animated: Bool, completion: (() -> Void)?) {
@@ -79,9 +92,7 @@ public class DuckableContainerViewController: UIViewController, DuckableViewCont
         nav.modalPresentationStyle = .custom
         nav.transitioningDelegate = self
         present(nav, animated: animated) {
-            self.bottomConstraint.isActive = false
+            self.configureChildForDuckedPlaceholder()
-            self.bottomConstraint = self.child.view.bottomAnchor.constraint(equalTo: self.view.safeAreaLayoutGuide.bottomAnchor, constant: -detentHeight - 4)
-            self.bottomConstraint.isActive = true
             completion?()
         }
     }
@@ -127,10 +138,18 @@ public class DuckableContainerViewController: UIViewController, DuckableViewCont
         }
         let placeholder = createPlaceholderForDuckedViewController(viewController)
         state = .ducked(viewController, placeholder: placeholder)
+        configureChildForDuckedPlaceholder()
+        dismiss(animated: true)
+    }
+    
+    private func configureChildForDuckedPlaceholder() {
+        bottomConstraint.isActive = false
+        bottomConstraint = child.view.bottomAnchor.constraint(equalTo: view.safeAreaLayoutGuide.bottomAnchor, constant: -detentHeight - 4)
+        bottomConstraint.isActive = true
+        
         child.view.layer.cornerRadius = duckedCornerRadius
         child.view.layer.maskedCorners = [.layerMinXMaxYCorner, .layerMaxXMaxYCorner]
         child.view.layer.masksToBounds = true
-        dismiss(animated: true)
     }
     
     @objc func unduckViewController() {
@@ -191,7 +210,10 @@ extension DuckableContainerViewController: UIViewControllerTransitioningDelegate
 @available(iOS 16.0, *)
 extension DuckableContainerViewController: UISheetPresentationControllerDelegate {
     public func presentationController(_ presentationController: UIPresentationController, willPresentWithAdaptiveStyle style: UIModalPresentationStyle, transitionCoordinator: UIViewControllerTransitionCoordinator?) {
-        let snapshot = child.view.snapshotView(afterScreenUpdates: false)!
+        guard let snapshot = child.view.snapshotView(afterScreenUpdates: false) else {
+            setOverrideTraitCollection(UITraitCollection(userInterfaceLevel: .elevated), forChild: child)
+            return
+        }
         snapshot.translatesAutoresizingMaskIntoConstraints = false
         self.view.addSubview(snapshot)
         NSLayoutConstraint.activate([

Tusker/Screens/Compose/ComposeHostingController.swift

@@ -43,11 +43,11 @@ class ComposeHostingController: UIHostingController<ComposeHostingController.Wra
         super.init(rootView: wrapper)
         
         self.uiState.delegate = self
-        
         pasteConfiguration = UIPasteConfiguration(forAccepting: CompositionAttachment.self)
-        
         userActivity = UserActivityManager.newPostActivity(accountID: mastodonController.accountInfo!.id)
         
+        updateNavigationTitle(draft: uiState.draft)
+        
         self.uiState.$draft
             .flatMap(\.objectWillChange)
             .debounce(for: .milliseconds(250), scheduler: DispatchQueue.global(qos: .utility))
@@ -55,12 +55,27 @@ class ComposeHostingController: UIHostingController<ComposeHostingController.Wra
                 DraftsManager.save()
             }
             .store(in: &cancellables)
+        
+        self.uiState.$draft
+            .sink { [unowned self] draft in
+                self.updateNavigationTitle(draft: draft)
+            }
+            .store(in: &cancellables)
     }
     
     required init?(coder aDecoder: NSCoder) {
         fatalError("init(coder:) has not been implemented")
     }
     
+    private func updateNavigationTitle(draft: Draft) {
+        if let id = draft.inReplyToID,
+           let status = mastodonController.persistentContainer.status(for: id) {
+            navigationItem.title = "Reply to @\(status.account.acct)"
+        } else {
+            navigationItem.title = "New Post"
+        }
+    }
+    
     override func viewWillDisappear(_ animated: Bool) {
         super.viewWillDisappear(animated)
         

Tusker/Screens/Compose/ComposeView.swift

@@ -107,7 +107,6 @@ struct ComposeView: View {
                     globalFrameOutsideList = frame
                 }
         })
-        .navigationTitle(navTitle)
         .sheet(isPresented: $uiState.isShowingDraftsList) {
             DraftsView(currentDraft: draft, mastodonController: mastodonController)
         }
@@ -211,15 +210,6 @@ struct ComposeView: View {
         }.frame(height: 50)
     }
     
-    private var navTitle: Text {
-        if let id = draft.inReplyToID,
-           let status = mastodonController.persistentContainer.status(for: id) {
-            return Text("Reply to @\(status.account.acct)")
-        } else {
-            return Text("New Post")
-        }
-    }
-    
     private var cancelButton: some View {
         Button(action: self.cancel) {
             Text("Cancel")

Tusker/Screens/Main/Duckable+Root.swift

@@ -12,10 +12,21 @@ import Duckable
 @available(iOS 16.0, *)
 extension DuckableContainerViewController: TuskerRootViewController {
     func stateRestorationActivity() -> NSUserActivity? {
-        (child as? TuskerRootViewController)?.stateRestorationActivity()
+        var activity = (child as? TuskerRootViewController)?.stateRestorationActivity()
+        if let compose = duckedViewController as? ComposeHostingController,
+           compose.draft.hasContent {
+            activity = UserActivityManager.addDuckedDraft(to: activity, draft: compose.draft)
+        }
+        return activity
     }
     
     func restoreActivity(_ activity: NSUserActivity) {
+        if let draft = UserActivityManager.getDraft(from: activity),
+           let account = UserActivityManager.getAccount(from: activity) {
+            let mastodonController = MastodonController.getForAccount(account)
+            let compose = ComposeHostingController(draft: draft, mastodonController: mastodonController)
+            _ = presentDuckable(compose, animated: false, isDucked: true)
+        }
         (child as? TuskerRootViewController)?.restoreActivity(activity)
     }
     

Tusker/Screens/Main/MainTabBarViewController.swift

@@ -13,11 +13,14 @@ class MainTabBarViewController: UITabBarController, UITabBarControllerDelegate {
     weak var mastodonController: MastodonController!
     
     private var composePlaceholder: UIViewController!
-    private var fastAccountSwitcher: FastAccountSwitcherViewController!
     
+    private var fastAccountSwitcher: FastAccountSwitcherViewController!
     private var fastSwitcherIndicator: FastAccountSwitcherIndicatorView!
     private var fastSwitcherConstraints: [NSLayoutConstraint] = []
     
+    @available(iOS, obsoleted: 16.0)
+    private var draftToPresentOnAppear: Draft?
+    
     var selectedTab: Tab {
         return Tab(rawValue: selectedIndex)!
     }
@@ -85,6 +88,11 @@ class MainTabBarViewController: UITabBarController, UITabBarControllerDelegate {
     override func viewDidAppear(_ animated: Bool) {
         super.viewDidAppear(animated)
         stateRestorationLogger.info("MainTabBarViewController: viewDidAppear, selectedIndex=\(self.selectedIndex, privacy: .public)")
+        
+        if let draftToPresentOnAppear {
+            self.draftToPresentOnAppear = nil
+            compose(editing: draftToPresentOnAppear, animated: true)
+        }
     }
     
     override func viewDidLayoutSubviews() {
@@ -235,15 +243,29 @@ extension MainTabBarViewController: TuskerNavigationDelegate {
 extension MainTabBarViewController: TuskerRootViewController {
     func stateRestorationActivity() -> NSUserActivity? {
         let nav = viewController(for: .timelines) as! UINavigationController
-        guard let timelinePages = nav.viewControllers.first as? TimelinesPageViewController,
+        var activity: NSUserActivity?
-              let timelineVC = timelinePages.pageControllers[timelinePages.currentIndex] as? TimelineViewController else {
+        if let timelinePages = nav.viewControllers.first as? TimelinesPageViewController,
-            stateRestorationLogger.fault("MainTabBarViewController: Unable to create state restoration actiivty, couldn't find timeline/page VC")
+           let timelineVC = timelinePages.pageControllers[timelinePages.currentIndex] as? TimelineViewController {
-            return nil
+            activity = timelineVC.stateRestorationActivity()
+        } else {
+            stateRestorationLogger.fault("MainTabBarViewController: Unable to create state restoration activity, couldn't find timeline/page VC")
         }
-        return timelineVC.stateRestorationActivity()
+        if let presentedNav = presentedViewController as? UINavigationController,
+           let compose = presentedNav.viewControllers.first as? ComposeHostingController {
+            activity = UserActivityManager.addEditedDraft(to: activity, draft: compose.draft)
+        }
+        return activity
     }
     
     func restoreActivity(_ activity: NSUserActivity) {
+        func restoreEditedDraft() {
+            // on iOS 16+, this is handled by the duckable container
+            if #unavailable(iOS 16.0),
+               let draft = UserActivityManager.getDraft(from: activity) {
+                draftToPresentOnAppear = draft
+            }
+        }
+        
         if activity.activityType == UserActivityType.showTimeline.rawValue {
             let nav = viewController(for: .timelines) as! UINavigationController
             guard let timelinePages = nav.viewControllers.first as? TimelinesPageViewController,
@@ -252,6 +274,10 @@ extension MainTabBarViewController: TuskerRootViewController {
                 return
             }
             timelineVC.restoreActivity(activity)
+            restoreEditedDraft()
+        } else if activity.activityType == UserActivityType.newPost.rawValue {
+            restoreEditedDraft()
+            return
         } else {
             stateRestorationLogger.fault("MainTabBarViewController: Unable to restore activity of unexpected type \(activity.activityType, privacy: .public)")
         }

Tusker/Shortcuts/UserActivityManager.swift

@@ -91,10 +91,37 @@ class UserActivityManager {
         return activity
     }
     
+    static func addDuckedDraft(to activity: NSUserActivity?, draft: Draft) -> NSUserActivity {
+        if let activity {
+            activity.addUserInfoEntries(from: [
+                "duckedDraftID": draft.id.uuidString
+            ])
+            return activity
+        } else {
+            return editDraftActivity(id: draft.id, accountID: draft.accountID)
+        }
+    }
+    
+    static func addEditedDraft(to activity: NSUserActivity?, draft: Draft) -> NSUserActivity {
+        if let activity {
+            activity.addUserInfoEntries(from: [
+                "editedDraftID": draft.id.uuidString
+            ])
+            return activity
+        } else {
+            return editDraftActivity(id: draft.id, accountID: draft.accountID)
+        }
+    }
+    
     static func getDraft(from activity: NSUserActivity) -> Draft? {
-        guard activity.activityType == UserActivityType.newPost.rawValue,
+        let idStr: String?
-              let str = activity.userInfo?["draftID"] as? String,
+        if activity.activityType == UserActivityType.newPost.rawValue {
-              let uuid = UUID(uuidString: str) else {
+            idStr = activity.userInfo?["draftID"] as? String
+        } else {
+            idStr = activity.userInfo?["duckedDraftID"] as? String ?? activity.userInfo?["editedDraftID"] as? String
+        }
+        guard let idStr,
+              let uuid = UUID(uuidString: idStr) else {
             return nil
         }
         return DraftsManager.shared.getBy(id: uuid)

Tusker/TuskerNavigationDelegate.swift

@@ -88,7 +88,7 @@ extension TuskerNavigationDelegate {
         show(conversation(mainStatusID: statusID, state: state), sender: self)
     }
     
-    func compose(editing draft: Draft) {
+    func compose(editing draft: Draft, animated: Bool = true) {
         if UIDevice.current.userInterfaceIdiom == .pad || UIDevice.current.userInterfaceIdiom == .mac {
             let compose = UserActivityManager.editDraftActivity(id: draft.id, accountID: apiController.accountInfo!.id)
             let options = UIWindowScene.ActivationRequestOptions()
@@ -97,20 +97,20 @@ extension TuskerNavigationDelegate {
         } else {
             let compose = ComposeHostingController(draft: draft, mastodonController: apiController)
             if #available(iOS 16.0, *),
-               presentDuckable(compose) {
+               presentDuckable(compose, animated: animated) {
                 return
             } else {
                 let compose = ComposeHostingController(draft: draft, mastodonController: apiController)
                 let nav = UINavigationController(rootViewController: compose)
                 nav.presentationController?.delegate = compose
-                present(nav, animated: true)
+                present(nav, animated: animated)
             }
         }
     }
     
-    func compose(inReplyToID: String? = nil, mentioningAcct: String? = nil) {
+    func compose(inReplyToID: String? = nil, mentioningAcct: String? = nil, animated: Bool = true) {
         let draft = apiController.createDraft(inReplyToID: inReplyToID, mentioningAcct: mentioningAcct)
-        compose(editing: draft)
+        compose(editing: draft, animated: animated)
     }
     
     func loadingLargeImage(url: URL, cache: ImageCache, description: String?, animatingFrom sourceView: UIImageView) -> LoadingLargeImageViewController {