Fixes for multi-window support. (#5528)

* Correctly handle the re-opening of the main window.

Add an additional safe-guard to ensure only one main window exists.
Make sure all secondary windows use the correct tint colour.

* Fix a bug where the settings screen isn't shown on macOS when the AppLock feature is enabled.

ElementX/Sources/Application/Windowing/SceneDelegate.swift

@@ -14,8 +14,18 @@ import SwiftUI
 class SceneDelegate: NSObject, UIWindowSceneDelegate {
     weak static var windowManager: SecureWindowManagerProtocol!
     
+    /// The app's main window scene identifier.
+    static let mainSceneID = "Main"
+    /// The user info key used by SwiftUI for a `WindowGroup`s `id` parameter.
+    static let sceneIDKey = "com.apple.SwiftUI.sceneID"
+    
     func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {
         guard let windowScene = scene as? UIWindowScene else { return }
         Self.windowManager.configure(withScene: windowScene, session: session)
     }
+    
+    func sceneDidDisconnect(_ scene: UIScene) {
+        guard let windowScene = scene as? UIWindowScene else { return }
+        Self.windowManager.handleSceneDisconnection(windowScene)
+    }
 }

ElementX/Sources/Application/Windowing/WindowManager.swift

@@ -48,15 +48,28 @@ class WindowManager: SecureWindowManagerProtocol {
     }
     
     func configure(withScene scene: UIWindowScene, session: UISceneSession) {
-        // This gets called for all opened windows, we're only interested in the
-        // first call, for the main window (works with state restoration too).
-        guard mainWindow == nil else {
+        // This gets called for all opened windows, we're only interested in the main window.
+        guard let userInfo = session.userInfo, userInfo[SceneDelegate.sceneIDKey] as? String == SceneDelegate.mainSceneID else {
+            scene.windows.forEach { $0.tintColor = .compound.textActionPrimary } // SecondaryWindow tinting.
+            return
+        }
+        
+        // Don't allow more than 1 main window to be presented.
+        if mainScene != nil {
+            // The window will be presented momentarily, so lets leave it blank.
+            scene.keyWindow?.rootViewController = UIHostingController(rootView: Color.clear)
+            UIApplication.shared.requestSceneSessionDestruction(session, options: nil)
             return
         }
         
         mainScene = scene
         mainSession = session
         
+        // Restore the previous window size on macOS as this isn't automatic.
+        if let previousSize = mainWindow?.frame.size {
+            scene.resizeWindowOnMac(to: previousSize)
+        }
+        
         mainWindow = scene.keyWindow
         mainWindow.tintColor = .compound.textActionPrimary
         
@@ -76,12 +89,20 @@ class WindowManager: SecureWindowManagerProtocol {
         delegate?.windowManagerDidConfigureWindows(self)
     }
     
-    func configure(withOpenWinddowAction openWindowAction: OpenWindowAction,
+    func configure(withOpenWindowAction openWindowAction: OpenWindowAction,
                    dismissWindowAction: DismissWindowAction) {
         self.openWindowAction = openWindowAction
         self.dismissWindowAction = dismissWindowAction
     }
     
+    func handleSceneDisconnection(_ scene: UIWindowScene) {
+        if scene == mainScene {
+            mainScene = nil
+            mainSession = nil
+            // Leave the mainWindow so we can reapply it's size on macOS.
+        }
+    }
+    
     func handleRoute(_ appRoute: AppRoute, windowType: SecondaryWindowType) {
         MXLog.info("Handling app route: \(appRoute) for window type: \(windowType)")
         
@@ -258,3 +279,19 @@ private struct InstantlyDismissingWindow: View {
             }
     }
 }
+
+private extension UIWindowScene {
+    func resizeWindowOnMac(to size: CGSize) {
+        // Hackity hack 🔨
+        guard ProcessInfo.processInfo.isiOSAppOnMac, let sizeRestrictions else { return }
+        
+        self.sizeRestrictions?.minimumSize = size
+        self.sizeRestrictions?.maximumSize = size
+        
+        Task {
+            try await Task.sleep(for: .milliseconds(100))
+            self.sizeRestrictions?.minimumSize = sizeRestrictions.minimumSize
+            self.sizeRestrictions?.maximumSize = sizeRestrictions.maximumSize
+        }
+    }
+}

ElementX/Sources/Application/Windowing/WindowManagerProtocol.swift

@@ -25,7 +25,9 @@ protocol SecureWindowManagerProtocol: WindowManagerProtocol {
     /// Configures the window manager to operate on the supplied scene.
     func configure(withScene scene: UIWindowScene, session: UISceneSession)
     
-    func configure(withOpenWinddowAction openWindowAction: OpenWindowAction, dismissWindowAction: DismissWindowAction)
+    func configure(withOpenWindowAction openWindowAction: OpenWindowAction, dismissWindowAction: DismissWindowAction)
+    
+    func handleSceneDisconnection(_ scene: UIWindowScene)
     
     func handleRoute(_ appRoute: AppRoute, windowType: SecondaryWindowType)