Adopt the UIScene life cycle

WordPress/Classes/System/UITesting/UITestConfigurator.swift

@@ -7,7 +7,10 @@ struct UITestConfigurator {
         CommandLine.arguments.contains("-ui-testing")
     }
 
-    static func prepareApplicationForUITests(in app: UIApplication, window: UIWindow) {
+    /// Applies the process-scoped part of the UI-test setup: flag parsing and, when
+    /// requested, wiping persistent state. Must run at the very start of the launch
+    /// sequence, before anything reads the flags or touches Core Data and user defaults.
+    static func prepareApplicationForUITests() {
         let arguments = CommandLine.arguments
         if arguments.contains("-ui-testing") {
             flags.insert(.disableLogging)
@@ -23,7 +26,7 @@ struct UITestConfigurator {
         }
         if arguments.contains("-ui-test-disable-animations") {
             flags.insert(.disableAnimations)
-            disableAnimations(in: app, window: window)
+            UIView.setAnimationsEnabled(false)
         }
         if arguments.contains("-ui-test-use-mock-data") {
             flags.insert(.useMockData)
@@ -37,11 +40,13 @@ struct UITestConfigurator {
         }
     }
 
-    /// This method will disable animations and speed-up keyboad input if command-line arguments includes "NoAnimations"
-    /// It was designed to be used in UI test suites. To enable it just pass a launch argument into XCUIApplicaton.
-    private static func disableAnimations(in app: UIApplication, window: UIWindow) {
-        UIView.setAnimationsEnabled(false)
-        window.layer.speed = MAXFLOAT
+    /// Applies the window-scoped part of the UI-test setup. Runs whenever the main
+    /// window is created, which (under the scene life cycle) happens at scene connect,
+    /// after `prepareApplicationForUITests()` already parsed the flags.
+    static func prepareWindowForUITests(_ window: UIWindow) {
+        if isEnabled(.disableAnimations) {
+            window.layer.speed = MAXFLOAT
+        }
     }
 
     private static func resetEverything() {

WordPress/Classes/System/WordPressAppDelegate+openURL.swift

@@ -4,16 +4,8 @@ import WordPressData
 import WordPressShared
 
 @objc extension WordPressAppDelegate {
-    public func application(
-        _ app: UIApplication,
-        open url: URL,
-        options: [UIApplication.OpenURLOptionsKey: Any] = [:]
-    ) -> Bool {
-        handle(url: url)
-    }
-
     /// Routes an inbound URL (custom scheme deep links, magic-login, migration, OAuth).
-    /// Reused by both the legacy app-lifecycle path and `WordPressSceneDelegate`.
+    /// Called by `WordPressSceneDelegate` for inbound URLs.
     @discardableResult
     func handle(url: URL) -> Bool {
         let redactedURL = LoggingURLRedactor.redactedURL(url)

WordPress/Classes/System/WordPressAppDelegate.swift

@@ -35,9 +35,15 @@ public class WordPressAppDelegate: UIResponder, UIApplicationDelegate {
 
     @objc
     lazy var windowManager: WindowManager = {
-        guard let window else {
-            fatalError("The App cannot run without a window.")
-        }
+        if window == nil {
+            // Reachable only when a code path builds UI before any scene has connected
+            // (e.g. during a background launch); such paths should be guarded instead.
+            // Recover by creating the window now: `WordPressSceneDelegate` attaches it to
+            // the scene once one connects.
+            assertionFailure("windowManager accessed before any scene connected")
+            window = UIWindow(frame: UIScreen.main.bounds)
+        }
+        let window = window!
         return switch BuildSettings.current.brand {
         case .wordpress: WindowManager(window: window)
         case .jetpack: JetpackWindowManager(window: window)
@@ -94,18 +100,14 @@ public class WordPressAppDelegate: UIResponder, UIApplicationDelegate {
             ])
         }
 
-        let window = UIWindow(frame: UIScreen.main.bounds)
-        self.window = window
-
         WordPressAPIInternal.setupLogger(appId: Bundle.main.bundleIdentifier!)
         DesignSystem.FontManager.registerCustomFonts()
         AssertionLoggerDependencyContainer.logger = AssertionLogger()
-        UITestConfigurator.prepareApplicationForUITests(in: application, window: window)
+        UITestConfigurator.prepareApplicationForUITests()
 
         // The following extensive logging configuration detects if extensive logging is enabled internally.
         wpkURLSessionNotifyingDelegate = PulseNetworkLogger()
 
-        AppAppearance.overrideAppearance()
         MemoryCache.shared.register()
         MediaImageService.migrateCacheIfNeeded()
         PostCoordinator.shared.delegate = self
@@ -116,27 +118,98 @@ public class WordPressAppDelegate: UIResponder, UIApplicationDelegate {
         // Configure WPCom API overrides
         configureWordPressComApi()
 
-        configureWordPressAuthenticator()
-
         ReachabilityUtils.configure()
 
         configureSelfHostedChallengeHandler()
         updateFeatureFlags()
         updateRemoteConfig()
 
-        window.makeKeyAndVisible()
-
         // Restore a disassociated account prior to fixing tokens.
         AccountService(coreDataStack: ContextManager.shared).restoreDisassociatedAccountIfNecessary()
 
-        customizeAppearance()
         configureAnalytics()
 
-        runStartupSequence(with: launchOptions ?? [:])
+        runStartupSequence()
 
         return true
     }
 
+    /// Opts the app into the UIScene life cycle and names the scene delegate. Doing
+    /// this in code (instead of a UIApplicationSceneManifest in each Info.plist)
+    /// keeps the configuration in one place for all three app targets. The unit test
+    /// host runs TestingAppDelegate, which doesn't implement this method, so tests
+    /// keep the legacy life cycle.
+    public func application(
+        _ application: UIApplication,
+        configurationForConnecting connectingSceneSession: UISceneSession,
+        options: UIScene.ConnectionOptions
+    ) -> UISceneConfiguration {
+        let configuration = UISceneConfiguration(name: nil, sessionRole: connectingSceneSession.role)
+        configuration.delegateClass = WordPressSceneDelegate.self
+        return configuration
+    }
+
+    /// Whether `showInitialUI(in:)` has already built the UI. The scene can disconnect
+    /// and reconnect while the process stays alive, so the build must run exactly once.
+    private(set) var hasConfiguredInitialUI = false
+
+    /// Set during the first scene connect, because `sceneWillEnterForeground` also
+    /// fires right after it. The legacy `applicationWillEnterForeground` did not fire
+    /// during a cold launch, and `handleWillEnterForeground` keeps those semantics.
+    private var isInitialSceneConnect = false
+
+    /// Builds and shows the app's UI in the given window scene. Runs when the main
+    /// scene connects, which (under the scene life cycle) is after `didFinishLaunching`
+    /// and can happen multiple times per process: the system may disconnect the scene
+    /// in the background and reconnect it later. After the first connect, the existing
+    /// window (with all its UI state) is simply reattached to the new scene.
+    func showInitialUI(in windowScene: UIWindowScene) {
+        if hasConfiguredInitialUI {
+            window?.windowScene = windowScene
+            window?.makeKeyAndVisible()
+            return
+        }
+        hasConfiguredInitialUI = true
+        isInitialSceneConnect = true
+
+        let window: UIWindow
+        if let existingWindow = self.window {
+            // Created by the `windowManager` emergency fallback before any scene
+            // connected; adopt it instead of orphaning the UI already built in it.
+            existingWindow.windowScene = windowScene
+            window = existingWindow
+        } else {
+            window = UIWindow(windowScene: windowScene)
+            self.window = window
+        }
+
+        UITestConfigurator.prepareWindowForUITests(window)
+
+        // Must run here (not in willFinishLaunching): it accesses `windowManager`,
+        // which requires `window`. startObservingAppleIDCredentialRevoked also
+        // requires the authenticator to be initialized first. A background-only
+        // launch therefore runs without the revocation observer; the
+        // `checkAppleIDCredentialState` call in `handleDidBecomeActive` covers the
+        // gap at the next foreground.
+        configureWordPressAuthenticator()
+        startObservingAppleIDCredentialRevoked()
+        customizeAppearance()
+        // Reapplies the user's saved light/dark override; reads the app's window, so it
+        // can only take effect once the window exists.
+        AppAppearance.overrideAppearance()
+
+        window.makeKeyAndVisible()
+
+        // The 3D Touch / Home Screen quick actions probe the trait collection of
+        // `UIApplication.shared.mainWindow`, which only exists once the window above is key.
+        shortcutCreator.createShortcutsIf3DTouchAvailable(AccountHelper.isLoggedIn)
+
+        windowManager.showUI()
+        restoreAppState()
+
+        DebugMenuViewController.configure(in: window)
+    }
+
     public func application(
         _ application: UIApplication,
         didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]? = nil
@@ -154,7 +227,6 @@ public class WordPressAppDelegate: UIResponder, UIApplicationDelegate {
         // (e.g. the share extension's background URL session) post notices that it
         // delivers as local notifications, with no UI visible.
         setupNoticePresenter()
-        DebugMenuViewController.configure(in: window)
         AppTips.initialize()
 
         // This was necessary to properly load fonts for the Stories editor. I believe external libraries may require this call to access fonts.
@@ -164,8 +236,6 @@ public class WordPressAppDelegate: UIResponder, UIApplicationDelegate {
                 CTFontManagerRegisterFontsForURL(url as CFURL, .process, nil)
             })
 
-        startObservingAppleIDCredentialRevoked()
-
         NotificationCenter.default.post(name: .applicationLaunchCompleted, object: nil)
         DispatchQueue.main.asyncAfter(deadline: .now() + .seconds(2)) {
             WKWebView.warmup()
@@ -183,22 +253,6 @@ public class WordPressAppDelegate: UIResponder, UIApplicationDelegate {
         Loggers.app.info("\(self) \(#function)")
     }
 
-    public func applicationDidEnterBackground(_ application: UIApplication) {
-        handleDidEnterBackground()
-    }
-
-    public func applicationWillEnterForeground(_ application: UIApplication) {
-        handleWillEnterForeground()
-    }
-
-    public func applicationWillResignActive(_ application: UIApplication) {
-        handleWillResignActive()
-    }
-
-    public func applicationDidBecomeActive(_ application: UIApplication) {
-        handleDidBecomeActive()
-    }
-
     // MARK: - Activation handlers (shared by app- and scene-lifecycle)
 
     func handleDidEnterBackground() {
@@ -232,9 +286,21 @@ public class WordPressAppDelegate: UIResponder, UIApplicationDelegate {
     func handleWillEnterForeground() {
         Loggers.app.info("\(self) \(#function)")
 
+        // Refresh on every foreground, including the one right after the initial
+        // scene connect: a background-launched process may sit for hours between
+        // the launch-time refresh and the user opening the app.
         updateFeatureFlags()
         updateRemoteConfig()
 
+        // Skip the migration check on the call that follows the initial scene
+        // connect: the window phase already ran it via `windowManager.showUI()`,
+        // and running it twice emits its analytics event twice per launch. Scene
+        // reconnects are a real return from the background and fall through.
+        if isInitialSceneConnect {
+            isInitialSceneConnect = false
+            return
+        }
+
         // JetpackWindowManager is only available in the Jetpack target.
         if let windowManager = windowManager as? JetpackWindowManager {
             windowManager.startMigrationFlowIfNeeded()
@@ -256,15 +322,6 @@ public class WordPressAppDelegate: UIResponder, UIApplicationDelegate {
         GutenbergSettings().performGutenbergPhase2MigrationIfNeeded()
     }
 
-    public func application(
-        _ application: UIApplication,
-        performActionFor shortcutItem: UIApplicationShortcutItem,
-        completionHandler: @escaping (Bool) -> Void
-    ) {
-        let handler = WP3DTouchShortcutHandler()
-        completionHandler(handler.handleShortcutItem(shortcutItem))
-    }
-
     public func application(
         _ application: UIApplication,
         handleEventsForBackgroundURLSession identifier: String,
@@ -280,15 +337,6 @@ public class WordPressAppDelegate: UIResponder, UIApplicationDelegate {
         }
     }
 
-    public func application(
-        _ application: UIApplication,
-        continue userActivity: NSUserActivity,
-        restorationHandler: @escaping ([UIUserActivityRestoring]?) -> Void
-    ) -> Bool {
-        handle(userActivity: userActivity)
-        return true
-    }
-
     /// Routes an inbound `NSUserActivity` (universal links via web browsing, Spotlight, Handoff).
     func handle(userActivity: NSUserActivity) {
         if userActivity.activityType == NSUserActivityTypeBrowsingWeb {
@@ -316,7 +364,7 @@ public class WordPressAppDelegate: UIResponder, UIApplicationDelegate {
 
     // MARK: - Setup
 
-    func runStartupSequence(with launchOptions: [UIApplication.LaunchOptionsKey: Any] = [:]) {
+    func runStartupSequence() {
         // Local notifications
         addNotificationObservers()
 
@@ -329,7 +377,7 @@ public class WordPressAppDelegate: UIResponder, UIApplicationDelegate {
             TracksLogging.delegate = libraryLogger
             WPKitSetLoggingDelegate(libraryLogger)
             WPSetLoggingDelegate(libraryLogger)
-            printDebugLaunchInfoWithLaunchOptions(launchOptions)
+            printDebugLaunchInfo()
             toggleExtraDebuggingIfNeeded()
         }
 
@@ -366,12 +414,7 @@ public class WordPressAppDelegate: UIResponder, UIApplicationDelegate {
 
         setupWordPressExtensions()
 
-        shortcutCreator.createShortcutsIf3DTouchAvailable(AccountHelper.isLoggedIn)
-
         AccountService.loadDefaultAccountCookies()
-
-        windowManager.showUI()
-        restoreAppState()
     }
 
     private func mergeDuplicateAccountsIfNeeded() {
@@ -630,7 +673,7 @@ extension WordPressAppDelegate {
 // MARK: - Debugging
 
 extension WordPressAppDelegate {
-    func printDebugLaunchInfoWithLaunchOptions(_ launchOptions: [UIApplication.LaunchOptionsKey: Any]? = nil) {
+    func printDebugLaunchInfo() {
         let unknown = "Unknown"
 
         let device = UIDevice.current
@@ -665,7 +708,6 @@ extension WordPressAppDelegate {
         Loggers.app.info("Language:  \(currentLanguage)")
         Loggers.app.info("UDID:      \(udid)")
         Loggers.app.info("APN token: \(PushNotificationsManager.shared.deviceToken ?? "None")")
-        Loggers.app.info("Launch options: \(String(describing: launchOptions ?? [:]))")
 
         AccountHelper.logBlogsAndAccounts(context: mainContext)
         Loggers.app.info("===========================================================================")
@@ -745,14 +787,26 @@ extension WordPressAppDelegate {
         // If the notification object is not nil, then it's a login
         if notification.object != nil {
             setupWordPressExtensions()
-            startObservingAppleIDCredentialRevoked()
+            // Pre-UI logins (the observer requires the authenticator, which is
+            // configured at first scene connect) are covered by `showInitialUI`,
+            // which registers the observer itself.
+            if hasConfiguredInitialUI {
+                startObservingAppleIDCredentialRevoked()
+            }
             AccountService.loadDefaultAccountCookies()
         } else {
             trackLogoutIfNeeded()
             removeShareExtensionConfiguration()
             removeNotificationExtensionConfiguration()
-            windowManager.showFullscreenSignIn()
-            stopObservingAppleIDCredentialRevoked()
+            // Skip when the UI was never built (e.g. the account is removed during a
+            // background launch): there is no UI to show sign-in in, `showInitialUI`
+            // shows it anyway once a scene connects and finds no account, and the
+            // Apple ID observer was never registered (stopping it would hit
+            // `WordPressAuthenticator.shared` before the authenticator exists).
+            if hasConfiguredInitialUI {
+                windowManager.showFullscreenSignIn()
+                stopObservingAppleIDCredentialRevoked()
+            }
             clearReaderStuff()
         }