Implement UI for migration errors

4 files changed, 113 insertions, 16 deletions

diff --git a/ios/MullvadVPN.xcodeproj/project.pbxproj b/ios/MullvadVPN.xcodeproj/project.pbxproj
index 4f7aaa8a3e..ccdeee7e73 100644
--- a/ios/MullvadVPN.xcodeproj/project.pbxproj
+++ b/ios/MullvadVPN.xcodeproj/project.pbxproj
@@ -293,6 +293,7 @@
 		58E0729F28814ACC008902F8 /* WireGuardLogLevel+Logging.swift in Sources */ = {isa = PBXBuildFile; fileRef = 58E0729E28814ACC008902F8 /* WireGuardLogLevel+Logging.swift */; };
 		58E072A128814B0E008902F8 /* MullvadEndpoint+WgEndpoint.swift in Sources */ = {isa = PBXBuildFile; fileRef = 58E072A028814B0E008902F8 /* MullvadEndpoint+WgEndpoint.swift */; };
 		58E0A98827C8F46300FE6BDD /* Tunnel.swift in Sources */ = {isa = PBXBuildFile; fileRef = 58E0A98727C8F46300FE6BDD /* Tunnel.swift */; };
+		58E11188292FA11F009FCA84 /* SettingsMigrationUIHandler.swift in Sources */ = {isa = PBXBuildFile; fileRef = 58E11187292FA11F009FCA84 /* SettingsMigrationUIHandler.swift */; };
 		58E20771274672CA00DE5D77 /* LaunchViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = 58E20770274672CA00DE5D77 /* LaunchViewController.swift */; };
 		58E25F812837BBBB002CFB2C /* SceneDelegate.swift in Sources */ = {isa = PBXBuildFile; fileRef = 58E25F802837BBBB002CFB2C /* SceneDelegate.swift */; };
 		58E511E628DDDEAC00B0BCDE /* CodingErrors+CustomErrorDescription.swift in Sources */ = {isa = PBXBuildFile; fileRef = 58E511E528DDDEAC00B0BCDE /* CodingErrors+CustomErrorDescription.swift */; };
@@ -788,6 +789,7 @@
 		58E072A028814B0E008902F8 /* MullvadEndpoint+WgEndpoint.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "MullvadEndpoint+WgEndpoint.swift"; sourceTree = "<group>"; };
 		58E072A428814C28008902F8 /* TunnelMonitorDelegate.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = TunnelMonitorDelegate.swift; sourceTree = "<group>"; };
 		58E0A98727C8F46300FE6BDD /* Tunnel.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Tunnel.swift; sourceTree = "<group>"; };
+		58E11187292FA11F009FCA84 /* SettingsMigrationUIHandler.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SettingsMigrationUIHandler.swift; sourceTree = "<group>"; };
 		58E20770274672CA00DE5D77 /* LaunchViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = LaunchViewController.swift; sourceTree = "<group>"; };
 		58E25F802837BBBB002CFB2C /* SceneDelegate.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SceneDelegate.swift; sourceTree = "<group>"; };
 		58E511E028DDB7F100B0BCDE /* WrappingError.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = WrappingError.swift; sourceTree = "<group>"; };
@@ -1410,6 +1412,7 @@
 				58CCA0152242560B004F3011 /* UIColor+Palette.swift */,
 				585CA70E25F8C44600B47C62 /* UIMetrics.swift */,
 				58F7CA872692E34000FC59FD /* WireguardKeysContentView.swift */,
+				58E11187292FA11F009FCA84 /* SettingsMigrationUIHandler.swift */,
 			);
 			path = MullvadVPN;
 			sourceTree = "<group>";
@@ -2261,6 +2264,7 @@
 				5888AD83227B11080051EB06 /* SelectLocationCell.swift in Sources */,
 				5891BF1C25E3E3EB006D6FB0 /* Bundle+ProductVersion.swift in Sources */,
 				5878A26F2907E7E00096FC88 /* ProblemReportInteractor.swift in Sources */,
+				58E11188292FA11F009FCA84 /* SettingsMigrationUIHandler.swift in Sources */,
 				5807E2C02432038B00F5FF30 /* String+Split.swift in Sources */,
 				58677712290976FB006F721F /* SettingsInteractor.swift in Sources */,
 				58CE5E66224146200008646E /* LoginViewController.swift in Sources */,
diff --git a/ios/MullvadVPN/AppDelegate.swift b/ios/MullvadVPN/AppDelegate.swift
index b11ada5f7c..1721f80261 100644
--- a/ios/MullvadVPN/AppDelegate.swift
+++ b/ios/MullvadVPN/AppDelegate.swift
@@ -110,28 +110,48 @@ class AppDelegate: UIResponder, UIApplicationDelegate, UNUserNotificationCenterD
         setupNotificationHandler()
         addApplicationNotifications(application: application)
 
-        let setupTunnelManagerOperation =
-            AsyncBlockOperation(dispatchQueue: .main) { operation in
-                SettingsManager.migrateStore(with: self.proxyFactory) { error in
-                    precondition(error == nil)
-
-                    self.tunnelManager.loadConfiguration { error in
-                        // TODO: avoid throwing fatal error and show the problem report UI instead.
-                        if let error = error {
-                            fatalError(error.localizedDescription)
-                        }
+        let migrateSettingsOperation = AsyncBlockOperation(dispatchQueue: .main) { operation in
+            SettingsManager.migrateStore(with: self.proxyFactory) { error in
+                guard let error = error else {
+                    operation.finish()
+                    return
+                }
 
-                        self.logger.debug("Finished initialization.")
+                guard let migrationUIHandler = application.connectedScenes.compactMap({ scene in
+                    return scene.delegate as? SettingsMigrationUIHandler
+                }).first else {
+                    operation.finish()
+                    return
+                }
 
-                        NotificationManager.shared.updateNotifications()
-                        self.storePaymentManager.startPaymentQueueMonitoring()
+                migrationUIHandler.showMigrationError(error) {
+                    operation.finish()
+                }
+            }
+        }
 
-                        operation.finish()
+        let loadTunnelConfigurationOperation =
+            AsyncBlockOperation(dispatchQueue: .main) { operation in
+                self.tunnelManager.loadConfiguration { error in
+                    // TODO: avoid throwing fatal error and show the problem report UI instead.
+                    if let error = error {
+                        fatalError(error.localizedDescription)
                     }
+
+                    self.logger.debug("Finished initialization.")
+
+                    NotificationManager.shared.updateNotifications()
+                    self.storePaymentManager.startPaymentQueueMonitoring()
+
+                    operation.finish()
                 }
             }
+        loadTunnelConfigurationOperation.addDependency(migrateSettingsOperation)
 
-        operationQueue.addOperation(setupTunnelManagerOperation)
+        operationQueue.addOperations(
+            [migrateSettingsOperation, loadTunnelConfigurationOperation],
+            waitUntilFinished: false
+        )
 
         return true
     }
diff --git a/ios/MullvadVPN/SceneDelegate.swift b/ios/MullvadVPN/SceneDelegate.swift
index 27fbfa7bf2..03f6bc3674 100644
--- a/ios/MullvadVPN/SceneDelegate.swift
+++ b/ios/MullvadVPN/SceneDelegate.swift
@@ -19,7 +19,7 @@ class SceneDelegate: UIResponder, UIWindowSceneDelegate, UISplitViewControllerDe
     SettingsNavigationControllerDelegate, ConnectViewControllerDelegate,
     OutOfTimeViewControllerDelegate, SelectLocationViewControllerDelegate,
     RevokedDeviceViewControllerDelegate, NotificationManagerDelegate, TunnelObserver,
-    RelayCacheTrackerObserver
+    RelayCacheTrackerObserver, SettingsMigrationUIHandler
 {
     private let logger = Logger(label: "SceneDelegate")
 
@@ -952,4 +952,64 @@ class SceneDelegate: UIResponder, UIWindowSceneDelegate, UISplitViewControllerDe
         }
         return nil
     }
+
+    // MARK: - SettingsMigrationUIHandler
+
+    func showMigrationError(_ error: Error, completionHandler: @escaping () -> Void) {
+        let alertController = UIAlertController(
+            title: NSLocalizedString(
+                "ALERT_TITLE",
+                tableName: "SettingsMigrationUI",
+                value: "Settings migration error",
+                comment: ""
+            ),
+            message: Self.migrationErrorReason(error),
+            preferredStyle: .alert
+        )
+        alertController.addAction(
+            UIAlertAction(
+                title: NSLocalizedString("OK", tableName: "SettingsMigrationUI", comment: ""),
+                style: .default,
+                handler: { _ in
+                    completionHandler()
+                }
+            )
+        )
+
+        if let rootViewController = window?.rootViewController {
+            rootViewController.present(alertController, animated: true)
+        } else {
+            completionHandler()
+        }
+    }
+
+    private static func migrationErrorReason(_ error: Error) -> String {
+        if error is UnsupportedSettingsVersionError {
+            return NSLocalizedString(
+                "NEWER_STORED_SETTINGS_ERROR",
+                tableName: "SettingsMigrationUI",
+                value: """
+                The version of settings stored on device is from a newer app than is currently \
+                running. Settings will be reset to defaults.
+                """,
+                comment: ""
+            )
+        } else if let error = error as? SettingsMigrationError,
+                  error.underlyingError is REST.Error
+        {
+            return NSLocalizedString(
+                "NETWORK_ERROR",
+                tableName: "SettingsMigrationUI",
+                value: "Network error occurred. Settings will be reset to defaults.",
+                comment: ""
+            )
+        } else {
+            return NSLocalizedString(
+                "INTERNAL_ERROR",
+                tableName: "SettingsMigrationUI",
+                value: "Internal error occurred. Settings will be reset to defaults.",
+                comment: ""
+            )
+        }
+    }
 }
diff --git a/ios/MullvadVPN/SettingsMigrationUIHandler.swift b/ios/MullvadVPN/SettingsMigrationUIHandler.swift
new file mode 100644
index 0000000000..949458e394
--- /dev/null
+++ b/ios/MullvadVPN/SettingsMigrationUIHandler.swift
@@ -0,0 +1,13 @@
+//
+//  SettingsMigrationUIHandler.swift
+//  MullvadVPN
+//
+//  Created by pronebird on 24/11/2022.
+//  Copyright © 2022 Mullvad VPN AB. All rights reserved.
+//
+
+import Foundation
+
+protocol SettingsMigrationUIHandler {
+    func showMigrationError(_ error: Error, completionHandler: @escaping () -> Void)
+}