Show an alert when entering an account provider that requires Element Pro. (#4326)

ElementX.xcodeproj/project.pbxproj

@@ -869,12 +869,14 @@
 		A4C29D373986AFE4559696D5 /* SecureBackupKeyBackupScreenViewModelProtocol.swift in Sources */ = {isa = PBXBuildFile; fileRef = 4525E8C0FBDD27D1ACE90952 /* SecureBackupKeyBackupScreenViewModelProtocol.swift */; };
 		A4E885358D7DD5A072A06824 /* PostHog in Frameworks */ = {isa = PBXBuildFile; productRef = CCE5BF78B125320CBF3BB834 /* PostHog */; };
 		A51C65E5A3C9F2464A91A380 /* AuthenticationClientBuilderFactoryMock.swift in Sources */ = {isa = PBXBuildFile; fileRef = 0554FEA301486A8CFA475D5A /* AuthenticationClientBuilderFactoryMock.swift */; };
+		A52090A4FE0DB826578DFC03 /* Client.swift in Sources */ = {isa = PBXBuildFile; fileRef = 0724EBDFE8BB4C9E5547C57D /* Client.swift */; };
 		A583B70939707197B0B21DFC /* DeferredFulfillmentTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = DEBB74427E24AF30CDB131B7 /* DeferredFulfillmentTests.swift */; };
 		A588572ED0EB18D947B32A5E /* SendInviteConfirmationView.swift in Sources */ = {isa = PBXBuildFile; fileRef = F276F31C1AEC19E52B951B62 /* SendInviteConfirmationView.swift */; };
 		A5B455D1A6DADF7476F7B417 /* EmojiProviderProtocol.swift in Sources */ = {isa = PBXBuildFile; fileRef = 8BCCE3D12B0A9C6E559B5B5A /* EmojiProviderProtocol.swift */; };
 		A5B9EF45C7B8ACEB4954AE36 /* LoginScreenViewModelProtocol.swift in Sources */ = {isa = PBXBuildFile; fileRef = 9780389F8A53E4D26E23DD03 /* LoginScreenViewModelProtocol.swift */; };
 		A5D551E5691749066E0E0C44 /* RoomDetailsScreenViewModel.swift in Sources */ = {isa = PBXBuildFile; fileRef = 837B440C4705E4B899BCB899 /* RoomDetailsScreenViewModel.swift */; };
 		A5FD8284744E2FECFC842FC1 /* TraceLogPack.swift in Sources */ = {isa = PBXBuildFile; fileRef = D7149BDDE47F8AD104E644E2 /* TraceLogPack.swift */; };
+		A63DA8A6D229889273A53D99 /* ElementWellKnownHook.swift in Sources */ = {isa = PBXBuildFile; fileRef = 0142FAE169CC4619D8A30262 /* ElementWellKnownHook.swift */; };
 		A64B52D9F73F9A6B95AF24FE /* UserDetailsEditScreenCoordinator.swift in Sources */ = {isa = PBXBuildFile; fileRef = C4CD503F5E0938FE53C7C6E7 /* UserDetailsEditScreenCoordinator.swift */; };
 		A6B83EB78F025D21B6EBA90C /* CompoundIcon.swift in Sources */ = {isa = PBXBuildFile; fileRef = 044E501B8331B339874D1B96 /* CompoundIcon.swift */; };
 		A6D4C5EEA85A6A0ABA1559D6 /* RoomDetailsEditScreenModels.swift in Sources */ = {isa = PBXBuildFile; fileRef = 16D09C79746BDCD9173EB3A7 /* RoomDetailsEditScreenModels.swift */; };
@@ -1399,6 +1401,7 @@
 		00E5B2CBEF8F96424F095508 /* RoomDetailsEditScreenViewModelTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = RoomDetailsEditScreenViewModelTests.swift; sourceTree = "<group>"; };
 		011AFA4990C585D157829679 /* DeclineAndBlockScreenViewModel.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = DeclineAndBlockScreenViewModel.swift; sourceTree = "<group>"; };
 		012A284622B32052015F1F89 /* ReadMarkerRoomTimelineView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ReadMarkerRoomTimelineView.swift; sourceTree = "<group>"; };
+		0142FAE169CC4619D8A30262 /* ElementWellKnownHook.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ElementWellKnownHook.swift; sourceTree = "<group>"; };
 		018194CAFBE80720FECCEDEE /* ZoomTransition.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ZoomTransition.swift; sourceTree = "<group>"; };
 		01B795AAAB7B8747FE2FF311 /* LogViewerScreenModels.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = LogViewerScreenModels.swift; sourceTree = "<group>"; };
 		01C4C7DB37597D7D8379511A /* Assets.xcassets */ = {isa = PBXFileReference; lastKnownFileType = folder.assetcatalog; path = Assets.xcassets; sourceTree = "<group>"; };
@@ -1435,6 +1438,7 @@
 		06B098A612DCB5A7358EECD5 /* DeveloperOptionsScreenModels.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = DeveloperOptionsScreenModels.swift; sourceTree = "<group>"; };
 		06F27F588F9059128E17C669 /* WindowManagerProtocol.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = WindowManagerProtocol.swift; sourceTree = "<group>"; };
 		06FAE373A7F20780BA84B59C /* MessageForwardingScreenCoordinator.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MessageForwardingScreenCoordinator.swift; sourceTree = "<group>"; };
+		0724EBDFE8BB4C9E5547C57D /* Client.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Client.swift; sourceTree = "<group>"; };
 		07579F9C29001E40715F3014 /* NotificationSettingsChatType.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = NotificationSettingsChatType.swift; sourceTree = "<group>"; };
 		077B01C13BBA2996272C5FB5 /* ProcessInfo.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ProcessInfo.swift; sourceTree = "<group>"; };
 		077D7C3BE199B6E5DDEC07EC /* AppCoordinatorStateMachine.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AppCoordinatorStateMachine.swift; sourceTree = "<group>"; };
@@ -3271,6 +3275,7 @@
 				3865AD7B7249C939D7C69C33 /* CertificateValidatorHook.swift */,
 				7AC0CD1CAFD3F8B057F9AEA5 /* ClientBuilderHook.swift */,
 				8B89D6C760E8CAE29CA28FB1 /* CompoundHook.swift */,
+				0142FAE169CC4619D8A30262 /* ElementWellKnownHook.swift */,
 				B343C5255FB408DDE853CFDF /* RoomScreenHook.swift */,
 			);
 			path = Hooks;
@@ -4674,6 +4679,7 @@
 		8039515BAA53B7C3275AC64A /* Client */ = {
 			isa = PBXGroup;
 			children = (
+				0724EBDFE8BB4C9E5547C57D /* Client.swift */,
 				18F2958E6D247AE2516BEEE8 /* ClientProxy.swift */,
 				6033779EB37259F27F938937 /* ClientProxyProtocol.swift */,
 			);
@@ -7261,6 +7267,7 @@
 				E14E469CD97550D0FC58F3CA /* CancellableTask.swift in Sources */,
 				DF8F1211F2B0B56F0FCCA5C2 /* CertificateValidatorHook.swift in Sources */,
 				D885B783B95AD7832D4EF5DD /* CharacterSet.swift in Sources */,
+				A52090A4FE0DB826578DFC03 /* Client.swift in Sources */,
 				C80E06ED97CE52704A46C148 /* ClientBuilder.swift in Sources */,
 				87CEA3E07B602705BC2D2A20 /* ClientBuilderHook.swift in Sources */,
 				1950A80CD198BED283DFC2CE /* ClientProxy.swift in Sources */,
@@ -7336,6 +7343,7 @@
 				07CC13C5729C24255348CBBD /* ElementCallWidgetDriver.swift in Sources */,
 				370AF5BFCD4384DD455479B6 /* ElementCallWidgetDriverProtocol.swift in Sources */,
 				A87DC550659C5176AC1829DE /* ElementTextFieldStyle.swift in Sources */,
+				A63DA8A6D229889273A53D99 /* ElementWellKnownHook.swift in Sources */,
 				7C1A7B594B2F8143F0DD0005 /* ElementXAttributeScope.swift in Sources */,
 				3A08584ECDD4A4541DBF21F8 /* EmojiLoaderProtocol.swift in Sources */,
 				340D39DB87F3800D53A6A621 /* EmojiPickerScreen.swift in Sources */,

ElementX/Resources/Localizations/en.lproj/Localizable.strings

@@ -659,6 +659,9 @@
 "screen_change_account_provider_other" = "Other";
 "screen_change_account_provider_subtitle" = "Use a different account provider, such as your own private server or a work account.";
 "screen_change_account_provider_title" = "Change account provider";
+"screen_change_server_error_element_pro_required_action_ios" = "App Store";
+"screen_change_server_error_element_pro_required_message" = "The Element Pro app is required on %1$@. Please download it from the store.";
+"screen_change_server_error_element_pro_required_title" = "Element Pro required";
 "screen_change_server_error_invalid_homeserver" = "We couldn't reach this homeserver. Please check that you have entered the homeserver URL correctly. If the URL is correct, contact your homeserver administrator for further help.";
 "screen_change_server_error_invalid_well_known" = "Server isn't available due to an issue in the .well-known file:\n%1$@";
 "screen_change_server_error_no_sliding_sync_message" = "The selected account provider does not support sliding sync. An upgrade to the server is needed to use %1$@.";

ElementX/Sources/AppHooks/AppHooks.swift

@@ -33,6 +33,11 @@ class AppHooks: AppHooksProtocol {
         certificateValidatorHook = hook
     }
     
+    private(set) var elementWellKnownHook: ElementWellKnownHookProtocol = DefaultElementWellKnownHook()
+    func registerElementWellKnownHook(_ hook: ElementWellKnownHookProtocol) {
+        elementWellKnownHook = hook
+    }
+    
     private(set) var roomScreenHook: RoomScreenHookProtocol = DefaultRoomScreenHook()
     func registerRoomScreenHook(_ hook: RoomScreenHookProtocol) {
         roomScreenHook = hook

ElementX/Sources/AppHooks/Hooks/ElementWellKnownHook.swift

@@ -0,0 +1,53 @@
+//
+// Copyright 2025 New Vector Ltd.
+//
+// SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+// Please see LICENSE files in the repository root for full details.
+//
+
+import Foundation
+import MatrixRustSDK
+
+protocol ElementWellKnownHookProtocol {
+    func validate(using client: ClientProtocol) async -> Result<Void, ElementWellKnownError>
+}
+
+struct DefaultElementWellKnownHook: ElementWellKnownHookProtocol {
+    /// A best effort implementation to let Element X advertise to users when they should be using
+    /// Element Pro. In an ideal world the backend would be able to validate the client's requests
+    /// instead of relying on it to check a well-known file for this.
+    func validate(using client: ClientProtocol) async -> Result<Void, ElementWellKnownError> {
+        guard case let .success(wellKnownData) = await client.elementWellKnown() else {
+            // Nothing to check, carry on as normal.
+            return .success(())
+        }
+        
+        do {
+            let wellKnown = try JSONDecoder().decode(ElementWellKnown.self, from: wellKnownData)
+            if wellKnown.enforceElementPro == true {
+                let serverName = client.server() ?? client.homeserver()
+                let displayableServerName = LoginHomeserver(address: serverName, loginMode: .unknown).address
+                return .failure(.elementProRequired(serverName: displayableServerName))
+            } else {
+                return .success(())
+            }
+        } catch {
+            // If it doesn't decode we have to assume it's a 404 page or similar.
+            return .success(())
+        }
+    }
+}
+
+private struct ElementWellKnown: Decodable {
+    var version: Int
+    var enforceElementPro: Bool?
+    
+    enum CodingKeys: String, CodingKey {
+        case version
+        case enforceElementPro = "enforce_element_pro"
+    }
+}
+
+enum ElementWellKnownError: Error {
+    case elementProRequired(serverName: String)
+}

ElementX/Sources/Application/AppSettings.swift

@@ -189,6 +189,9 @@ final class AppSettings {
     private(set) var elementWebHosts = ["app.element.io", "staging.element.io", "develop.element.io"]
     /// The domain that account provisioning links will be hosted on - used for handling the links.
     private(set) var accountProvisioningHost = "mobile.element.io"
+    /// The App Store URL for Element Pro, shown to the user when a homeserver requires that app.
+    /// **Note:** This property isn't overridable as it in unexpected for forks to come across the error (or to even have a "Pro" app).
+    let elementProAppStoreURL: URL = "https://apps.apple.com/app/element-pro-for-work/id6502951615"
     
     @UserPreference(key: UserDefaultsKeys.appAppearance, defaultValue: .system, storageType: .userDefaults(store))
     var appAppearance: AppAppearance

ElementX/Sources/FlowCoordinators/AuthenticationFlowCoordinator.swift

@@ -363,6 +363,7 @@ class AuthenticationFlowCoordinator: FlowCoordinatorProtocol {
         
         let parameters = ServerSelectionScreenCoordinatorParameters(authenticationService: authenticationService,
                                                                     authenticationFlow: authenticationFlow,
+                                                                    appSettings: appSettings,
                                                                     userIndicatorController: userIndicatorController)
         let coordinator = ServerSelectionScreenCoordinator(parameters: parameters)
         
@@ -408,6 +409,7 @@ class AuthenticationFlowCoordinator: FlowCoordinatorProtocol {
         let parameters = LoginScreenCoordinatorParameters(authenticationService: authenticationService,
                                                           loginHint: loginHint,
                                                           userIndicatorController: userIndicatorController,
+                                                          appSettings: appSettings,
                                                           analytics: analytics)
         let coordinator = LoginScreenCoordinator(parameters: parameters)
         

ElementX/Sources/Generated/Strings.swift

@@ -1258,6 +1258,14 @@ internal enum L10n {
   internal static var screenChangeAccountProviderSubtitle: String { return L10n.tr("Localizable", "screen_change_account_provider_subtitle") }
   /// Change account provider
   internal static var screenChangeAccountProviderTitle: String { return L10n.tr("Localizable", "screen_change_account_provider_title") }
+  /// App Store
+  internal static var screenChangeServerErrorElementProRequiredActionIos: String { return L10n.tr("Localizable", "screen_change_server_error_element_pro_required_action_ios") }
+  /// The Element Pro app is required on %1$@. Please download it from the store.
+  internal static func screenChangeServerErrorElementProRequiredMessage(_ p1: Any) -> String {
+    return L10n.tr("Localizable", "screen_change_server_error_element_pro_required_message", String(describing: p1))
+  }
+  /// Element Pro required
+  internal static var screenChangeServerErrorElementProRequiredTitle: String { return L10n.tr("Localizable", "screen_change_server_error_element_pro_required_title") }
   /// We couldn't reach this homeserver. Please check that you have entered the homeserver URL correctly. If the URL is correct, contact your homeserver administrator for further help.
   internal static var screenChangeServerErrorInvalidHomeserver: String { return L10n.tr("Localizable", "screen_change_server_error_invalid_homeserver") }
   /// Server isn't available due to an issue in the .well-known file:

ElementX/Sources/Mocks/AuthenticationClientBuilderFactoryMock.swift

@@ -25,11 +25,18 @@ extension AuthenticationClientFactoryMock {
                                                               supportsOIDCCreatePrompt: false,
                                                               supportsPasswordLogin: false)),
             "server.net": ClientSDKMock(configuration: .init(serverAddress: "server.net",
-                                                             homeserverURL: "https://matrix.example.com",
+                                                             homeserverURL: "https://matrix.server.net",
                                                              slidingSyncVersion: .native,
                                                              oidcLoginURL: nil,
                                                              supportsOIDCCreatePrompt: false,
-                                                             supportsPasswordLogin: false))
+                                                             supportsPasswordLogin: false)),
+            "secure.gov": ClientSDKMock(configuration: .init(serverAddress: "secure.gov",
+                                                             homeserverURL: "https://ess.secure.gov",
+                                                             slidingSyncVersion: .native,
+                                                             oidcLoginURL: "https://auth.secure.gov/oidc",
+                                                             supportsOIDCCreatePrompt: false,
+                                                             supportsPasswordLogin: false,
+                                                             elementWellKnown: "{\"version\":1,\"enforce_element_pro\":true}"))
         ]
     }
     

ElementX/Sources/Mocks/SDK/ClientSDKMock.swift

@@ -18,6 +18,7 @@ extension ClientSDKMock {
         var oidcLoginURL: String? = "https://account.matrix.org/authorize"
         var supportsOIDCCreatePrompt = true
         var supportsPasswordLogin = true
+        var elementWellKnown: String?
         var validCredentials = (username: "alice", password: "12345678")
         
         // MARK: Session
@@ -51,6 +52,14 @@ extension ClientSDKMock {
         
         userIdReturnValue = configuration.userID
         sessionReturnValue = configuration.session
+        getUrlUrlClosure = { url in
+            guard url.contains(".well-known/element/element.json") else { throw MockError.generic }
+            if let elementWellKnown = configuration.elementWellKnown {
+                return elementWellKnown
+            } else {
+                throw MockError.generic
+            }
+        }
     }
 }
 

ElementX/Sources/Screens/Authentication/LoginScreen/LoginScreenCoordinator.swift

@@ -14,6 +14,7 @@ struct LoginScreenCoordinatorParameters {
     /// An optional hint that can be used to pre-fill the form.
     let loginHint: String?
     let userIndicatorController: UserIndicatorControllerProtocol
+    let appSettings: AppSettings
     let analytics: AnalyticsService
 }
 
@@ -46,6 +47,7 @@ final class LoginScreenCoordinator: CoordinatorProtocol {
         viewModel = LoginScreenViewModel(authenticationService: parameters.authenticationService,
                                          loginHint: parameters.loginHint,
                                          userIndicatorController: parameters.userIndicatorController,
+                                         appSettings: parameters.appSettings,
                                          analytics: parameters.analytics)
     }
     

ElementX/Sources/Screens/Authentication/LoginScreen/LoginScreenModels.swift

@@ -70,6 +70,8 @@ enum LoginScreenErrorType: Hashable {
     case invalidWellKnownAlert(String)
     /// An alert that allows the user to learn about sliding sync.
     case slidingSyncAlert
+    /// An alert that informs the user that Element Pro should be used for a particular server.
+    case elementProAlert
     /// An alert that informs the user that login failed due to a refresh token being returned.
     case refreshTokenAlert
     /// The response from the homeserver was unexpected.

ElementX/Sources/Screens/Authentication/LoginScreen/LoginScreenViewModel.swift

@@ -13,6 +13,7 @@ typealias LoginScreenViewModelType = StateStoreViewModelV2<LoginScreenViewState,
 class LoginScreenViewModel: LoginScreenViewModelType, LoginScreenViewModelProtocol {
     private let authenticationService: AuthenticationServiceProtocol
     private let userIndicatorController: UserIndicatorControllerProtocol
+    private let appSettings: AppSettings
     private let analytics: AnalyticsService
     
     private var actionsSubject: PassthroughSubject<LoginScreenViewModelAction, Never> = .init()
@@ -23,9 +24,11 @@ class LoginScreenViewModel: LoginScreenViewModelType, LoginScreenViewModelProtoc
     init(authenticationService: AuthenticationServiceProtocol,
          loginHint: String?,
          userIndicatorController: UserIndicatorControllerProtocol,
+         appSettings: AppSettings,
          analytics: AnalyticsService) {
         self.authenticationService = authenticationService
         self.userIndicatorController = userIndicatorController
+        self.appSettings = appSettings
         self.analytics = analytics
         
         let username = switch loginHint {
@@ -146,6 +149,16 @@ class LoginScreenViewModel: LoginScreenViewModelType, LoginScreenViewModelProtoc
             
             // Clear out the invalid username to avoid an attempted login to matrix.org
             state.bindings.username = ""
+        case .elementProRequired(let serverName):
+            state.bindings.alertInfo = AlertInfo(id: .elementProAlert,
+                                                 title: L10n.screenChangeServerErrorElementProRequiredTitle,
+                                                 message: L10n.screenChangeServerErrorElementProRequiredMessage(serverName),
+                                                 primaryButton: .init(title: L10n.screenChangeServerErrorElementProRequiredActionIos) {
+                                                     UIApplication.shared.open(self.appSettings.elementProAppStoreURL)
+                                                 },
+                                                 secondaryButton: .init(title: L10n.actionCancel, role: .cancel, action: nil))
+            // Clear out the invalid username to avoid an attempted login to matrix.org
+            state.bindings.username = ""
         case .sessionTokenRefreshNotSupported:
             state.bindings.alertInfo = AlertInfo(id: .refreshTokenAlert,
                                                  title: L10n.commonServerNotSupported,

ElementX/Sources/Screens/Authentication/LoginScreen/View/LoginScreen.swift

@@ -159,6 +159,7 @@ struct LoginScreen_Previews: PreviewProvider, TestablePreview {
         let viewModel = LoginScreenViewModel(authenticationService: authenticationService,
                                              loginHint: nil,
                                              userIndicatorController: UserIndicatorControllerMock(),
+                                             appSettings: ServiceLocator.shared.settings,
                                              analytics: ServiceLocator.shared.analytics)
         
         if withCredentials {

ElementX/Sources/Screens/Authentication/ServerConfirmationScreen/ServerConfirmationScreenCoordinator.swift

@@ -40,6 +40,7 @@ final class ServerConfirmationScreenCoordinator: CoordinatorProtocol {
         viewModel = ServerConfirmationScreenViewModel(authenticationService: parameters.authenticationService,
                                                       mode: mode,
                                                       authenticationFlow: parameters.authenticationFlow,
+                                                      appSettings: parameters.appSettings,
                                                       userIndicatorController: parameters.userIndicatorController)
     }
     

ElementX/Sources/Screens/Authentication/ServerConfirmationScreen/ServerConfirmationScreenModels.swift

@@ -94,6 +94,8 @@ enum ServerConfirmationScreenAlert: Hashable {
     case login
     /// An alert that informs the user that registration isn't supported.
     case registration
+    /// An alert that informs the user that Element Pro should be used for a particular server.
+    case elementProRequired(serverName: String)
     /// An unknown error has occurred.
     case unknownError
 }

ElementX/Sources/Screens/Authentication/ServerConfirmationScreen/ServerConfirmationScreenViewModel.swift

@@ -13,6 +13,7 @@ typealias ServerConfirmationScreenViewModelType = StateStoreViewModelV2<ServerCo
 class ServerConfirmationScreenViewModel: ServerConfirmationScreenViewModelType, ServerConfirmationScreenViewModelProtocol {
     let authenticationService: AuthenticationServiceProtocol
     let authenticationFlow: AuthenticationFlow
+    let appSettings: AppSettings
     let userIndicatorController: UserIndicatorControllerProtocol
     
     private var actionsSubject: PassthroughSubject<ServerConfirmationScreenViewModelAction, Never> = .init()
@@ -24,9 +25,11 @@ class ServerConfirmationScreenViewModel: ServerConfirmationScreenViewModelType,
     init(authenticationService: AuthenticationServiceProtocol,
          mode: ServerConfirmationScreenMode,
          authenticationFlow: AuthenticationFlow,
+         appSettings: AppSettings,
          userIndicatorController: UserIndicatorControllerProtocol) {
         self.authenticationService = authenticationService
         self.authenticationFlow = authenticationFlow
+        self.appSettings = appSettings
         self.userIndicatorController = userIndicatorController
         
         let pickerSelection: String? = switch mode {
@@ -94,6 +97,8 @@ class ServerConfirmationScreenViewModel: ServerConfirmationScreenViewModelType,
                 displayError(.login)
             case .registrationNotSupported:
                 displayError(.registration)
+            case .elementProRequired(let serverName):
+                displayError(.elementProRequired(serverName: serverName))
             default:
                 displayError(.unknownError)
             }
@@ -184,6 +189,14 @@ class ServerConfirmationScreenViewModel: ServerConfirmationScreenViewModelType,
             state.bindings.alertInfo = AlertInfo(id: .registration,
                                                  title: L10n.commonServerNotSupported,
                                                  message: L10n.errorAccountCreationNotPossible)
+        case .elementProRequired(let serverName):
+            state.bindings.alertInfo = AlertInfo(id: .elementProRequired(serverName: serverName),
+                                                 title: L10n.screenChangeServerErrorElementProRequiredTitle,
+                                                 message: L10n.screenChangeServerErrorElementProRequiredMessage(serverName),
+                                                 primaryButton: .init(title: L10n.screenChangeServerErrorElementProRequiredActionIos) {
+                                                     UIApplication.shared.open(self.appSettings.elementProAppStoreURL)
+                                                 },
+                                                 secondaryButton: .init(title: L10n.actionCancel, role: .cancel, action: nil))
         case .unknownError:
             state.bindings.alertInfo = AlertInfo(id: .unknownError)
         }

ElementX/Sources/Screens/Authentication/ServerConfirmationScreen/View/ServerConfirmationScreen.swift

@@ -162,6 +162,7 @@ struct ServerConfirmationScreen_Previews: PreviewProvider, TestablePreview {
         ServerConfirmationScreenViewModel(authenticationService: AuthenticationService.mock,
                                           mode: mode,
                                           authenticationFlow: flow,
+                                          appSettings: ServiceLocator.shared.settings,
                                           userIndicatorController: UserIndicatorControllerMock())
     }
 }

ElementX/Sources/Screens/Authentication/ServerSelectionScreen/ServerSelectionScreenCoordinator.swift

@@ -12,6 +12,7 @@ struct ServerSelectionScreenCoordinatorParameters {
     /// The service used to authenticate the user.
     let authenticationService: AuthenticationServiceProtocol
     let authenticationFlow: AuthenticationFlow
+    let appSettings: AppSettings
     let userIndicatorController: UserIndicatorControllerProtocol
 }
 
@@ -38,6 +39,7 @@ final class ServerSelectionScreenCoordinator: CoordinatorProtocol {
         self.parameters = parameters
         viewModel = ServerSelectionScreenViewModel(authenticationService: parameters.authenticationService,
                                                    authenticationFlow: parameters.authenticationFlow,
+                                                   appSettings: parameters.appSettings,
                                                    userIndicatorController: parameters.userIndicatorController)
         userIndicatorController = parameters.userIndicatorController
     }

ElementX/Sources/Screens/Authentication/ServerSelectionScreen/ServerSelectionScreenModels.swift

@@ -66,4 +66,6 @@ enum ServerSelectionScreenErrorType: Hashable {
     case loginAlert
     /// An alert that informs the user that registration isn't supported.
     case registrationAlert
+    /// An alert that informs the user that Element Pro should be used for a particular server.
+    case elementProAlert
 }

ElementX/Sources/Screens/Authentication/ServerSelectionScreen/ServerSelectionScreenViewModel.swift

@@ -13,6 +13,7 @@ typealias ServerSelectionScreenViewModelType = StateStoreViewModelV2<ServerSelec
 class ServerSelectionScreenViewModel: ServerSelectionScreenViewModelType, ServerSelectionScreenViewModelProtocol {
     private let authenticationService: AuthenticationServiceProtocol
     private let authenticationFlow: AuthenticationFlow
+    private let appSettings: AppSettings
     private let userIndicatorController: UserIndicatorControllerProtocol
     
     private var actionsSubject: PassthroughSubject<ServerSelectionScreenViewModelAction, Never> = .init()
@@ -23,9 +24,11 @@ class ServerSelectionScreenViewModel: ServerSelectionScreenViewModelType, Server
 
     init(authenticationService: AuthenticationServiceProtocol,
          authenticationFlow: AuthenticationFlow,
+         appSettings: AppSettings,
          userIndicatorController: UserIndicatorControllerProtocol) {
         self.authenticationService = authenticationService
         self.authenticationFlow = authenticationFlow
+        self.appSettings = appSettings
         self.userIndicatorController = userIndicatorController
         
         let bindings = ServerSelectionScreenBindings(homeserverAddress: authenticationService.homeserver.value.address)
@@ -96,6 +99,14 @@ class ServerSelectionScreenViewModel: ServerSelectionScreenViewModelType, Server
             state.bindings.alertInfo = AlertInfo(id: .registrationAlert,
                                                  title: L10n.commonServerNotSupported,
                                                  message: L10n.errorAccountCreationNotPossible)
+        case .elementProRequired(let serverName):
+            state.bindings.alertInfo = AlertInfo(id: .elementProAlert,
+                                                 title: L10n.screenChangeServerErrorElementProRequiredTitle,
+                                                 message: L10n.screenChangeServerErrorElementProRequiredMessage(serverName),
+                                                 primaryButton: .init(title: L10n.screenChangeServerErrorElementProRequiredActionIos) {
+                                                     UIApplication.shared.open(self.appSettings.elementProAppStoreURL)
+                                                 },
+                                                 secondaryButton: .init(title: L10n.actionCancel, role: .cancel, action: nil))
         default:
             showFooterMessage(L10n.errorUnknown)
         }

ElementX/Sources/Screens/Authentication/ServerSelectionScreen/View/ServerSelectionScreen.swift

@@ -115,6 +115,7 @@ struct ServerSelection_Previews: PreviewProvider, TestablePreview {
         
         let viewModel = ServerSelectionScreenViewModel(authenticationService: authenticationService,
                                                        authenticationFlow: .login,
+                                                       appSettings: ServiceLocator.shared.settings,
                                                        userIndicatorController: UserIndicatorControllerMock())
         viewModel.context.homeserverAddress = homeserverAddress
         if homeserverAddress == "thisisbad" {

ElementX/Sources/Services/Authentication/AuthenticationService.swift

@@ -52,6 +52,7 @@ class AuthenticationService: AuthenticationServiceProtocol {
             var homeserver = LoginHomeserver(address: homeserverAddress, loginMode: .unknown)
             
             let client = try await makeClient(homeserverAddress: homeserverAddress)
+            try await appHooks.elementWellKnownHook.validate(using: client).get()
             let loginDetails = await client.homeserverLoginDetails()
             
             MXLog.info("Sliding sync: \(client.slidingSyncVersion())")
@@ -81,6 +82,8 @@ class AuthenticationService: AuthenticationServiceProtocol {
         } catch ClientBuildError.SlidingSyncVersion(let error) {
             MXLog.info("User entered a homeserver that isn't configured for sliding sync: \(error)")
             return .failure(.slidingSyncNotAvailable)
+        } catch ElementWellKnownError.elementProRequired(let serverName) {
+            return .failure(.elementProRequired(serverName: serverName))
         } catch {
             MXLog.error("Failed configuring a server: \(error)")
             return .failure(.invalidHomeserverAddress)
@@ -176,6 +179,7 @@ class AuthenticationService: AuthenticationServiceProtocol {
         
         do {
             let client = try await makeClient(homeserverAddress: scannedServerName)
+            try await appHooks.elementWellKnownHook.validate(using: client).get()
             try await client.loginWithQrCode(qrCodeData: qrData,
                                              oidcConfiguration: appSettings.oidcConfiguration.rustValue,
                                              progressListener: listener)
@@ -184,6 +188,8 @@ class AuthenticationService: AuthenticationServiceProtocol {
         } catch let error as HumanQrLoginError {
             MXLog.error("QRCode login error: \(error)")
             return .failure(error.serviceError)
+        } catch ElementWellKnownError.elementProRequired(let serverName) {
+            return .failure(.elementProRequired(serverName: serverName))
         } catch {
             MXLog.error("QRCode login unknown error: \(error)")
             return .failure(.qrCodeError(.unknown))

ElementX/Sources/Services/Authentication/AuthenticationServiceProtocol.swift

@@ -30,6 +30,7 @@ enum AuthenticationServiceError: Error, Equatable {
     case slidingSyncNotAvailable
     case loginNotSupported
     case registrationNotSupported
+    case elementProRequired(serverName: String)
     case accountDeactivated
     case failedLoggingIn
     case sessionTokenRefreshNotSupported

ElementX/Sources/Services/Client/Client.swift

@@ -0,0 +1,35 @@
+//
+// Copyright 2025 New Vector Ltd.
+//
+// SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+// Please see LICENSE files in the repository root for full details.
+//
+
+import Foundation
+import MatrixRustSDK
+
+extension ClientProtocol {
+    func elementWellKnown() async -> Result<Data, ClientProxyError> {
+        let serverNameURLString = if let userIDServerName = try? userIdServerName() {
+            "https://\(userIDServerName)"
+        } else {
+            server() ?? homeserver()
+        }
+        
+        do {
+            guard let url = URL(string: serverNameURLString)?.appending(path: "/.well-known/element/element.json") else {
+                return .failure(.invalidServerName)
+            }
+            
+            let response = try await getUrl(url: url.absoluteString)
+            
+            guard let data = response.data(using: .utf8) else {
+                return .failure(.invalidResponse)
+            }
+            
+            return .success(data)
+        } catch {
+            return .failure(.sdkError(error))
+        }
+    }
+}

ElementX/Sources/Services/Client/ClientProxyProtocol.swift

@@ -34,6 +34,7 @@ enum ClientProxyError: Error {
     
     case invalidMedia
     case invalidServerName
+    case invalidResponse
     case failedUploadingMedia(ErrorKind)
     case roomPreviewIsPrivate
     case failedRetrievingUserIdentity

ElementX/Sources/UITests/UITestsAppCoordinator.swift

@@ -117,6 +117,7 @@ class MockScreen: Identifiable {
             let navigationStackCoordinator = NavigationStackCoordinator()
             let coordinator = ServerSelectionScreenCoordinator(parameters: .init(authenticationService: AuthenticationService.mock,
                                                                                  authenticationFlow: .login,
+                                                                                 appSettings: ServiceLocator.shared.settings,
                                                                                  userIndicatorController: ServiceLocator.shared.userIndicatorController))
             navigationStackCoordinator.setRootCoordinator(coordinator)
             return navigationStackCoordinator

UnitTests/Sources/LoginScreenViewModelTests.swift

@@ -143,6 +143,21 @@ class LoginScreenViewModelTests: XCTestCase {
         XCTAssertEqual(context.alertInfo?.id, .unknown, "An alert should be shown to the user.")
     }
     
+    func testElementProRequired() async throws {
+        // Given the screen configured for matrix.org
+        await setupViewModel()
+        XCTAssertNil(context.alertInfo, "There shouldn't be an alert when the screen loads.")
+        
+        // When entering a username for an unsupported homeserver.
+        let deferred = deferFulfillment(context.observe(\.viewState.bindings.alertInfo)) { $0 != nil }
+        context.username = "@bob:secure.gov"
+        context.send(viewAction: .parseUsername)
+        try await deferred.fulfill()
+
+        // Then the view state should be updated to show an alert.
+        XCTAssertEqual(context.alertInfo?.id, .elementProAlert, "An alert should be shown to the user.")
+    }
+    
     func testLoginHint() async throws {
         await setupViewModel(loginHint: "")
         XCTAssertEqual(context.username, "")
@@ -172,6 +187,7 @@ class LoginScreenViewModelTests: XCTestCase {
         viewModel = LoginScreenViewModel(authenticationService: service,
                                          loginHint: loginHint,
                                          userIndicatorController: UserIndicatorControllerMock(),
+                                         appSettings: ServiceLocator.shared.settings,
                                          analytics: ServiceLocator.shared.analytics)
     }
 }

UnitTests/Sources/ServerConfirmationScreenViewModelTests.swift

@@ -196,6 +196,23 @@ class ServerConfirmationScreenViewModelTests: XCTestCase {
         XCTAssertEqual(context.alertInfo?.id, .login)
     }
     
+    func testElementProRequired() async throws {
+        // Given a view model for login using a service that hasn't been configured and the default server requires Element Pro.
+        setupViewModel(authenticationFlow: .login, supportsOIDC: false, supportsOIDCCreatePrompt: false, supportsPasswordLogin: false, requiresElementPro: true)
+        XCTAssertEqual(service.homeserver.value.loginMode, .unknown)
+        XCTAssertEqual(clientFactory.makeClientHomeserverAddressSessionDirectoriesPassphraseClientSessionDelegateAppSettingsAppHooksCallsCount, 0)
+        XCTAssertNil(context.alertInfo)
+        
+        // When continuing from the confirmation screen.
+        let deferred = deferFulfillment(context.observe(\.alertInfo)) { $0 != nil }
+        context.send(viewAction: .confirm)
+        try await deferred.fulfill()
+        
+        // Then the configuration should fail with an alert telling the user to download Element Pro.
+        XCTAssertEqual(clientFactory.makeClientHomeserverAddressSessionDirectoriesPassphraseClientSessionDelegateAppSettingsAppHooksCallsCount, 1)
+        XCTAssertEqual(context.alertInfo?.id, .elementProRequired(serverName: "matrix.org"))
+    }
+    
     // MARK: - Picker mode
     
     func testPickerWithoutConfiguration() async throws {
@@ -288,7 +305,8 @@ class ServerConfirmationScreenViewModelTests: XCTestCase {
                                 supportsOIDC: Bool = true,
                                 supportsOIDCCreatePrompt: Bool = true,
                                 supportsPasswordLogin: Bool = true,
-                                restrictedFlow: Bool = false) {
+                                restrictedFlow: Bool = false,
+                                requiresElementPro: Bool = false) {
         var mode = ServerConfirmationScreenMode.confirmation("matrix.org")
         if restrictedFlow {
             appSettings.override(accountProviders: ["matrix.org", "beta.matrix.org"],
@@ -315,7 +333,8 @@ class ServerConfirmationScreenViewModelTests: XCTestCase {
         // Manually create a configuration as the default homeserver address setting is immutable.
         client = ClientSDKMock(configuration: .init(oidcLoginURL: supportsOIDC ? "https://account.matrix.org/authorize" : nil,
                                                     supportsOIDCCreatePrompt: supportsOIDCCreatePrompt,
-                                                    supportsPasswordLogin: supportsPasswordLogin))
+                                                    supportsPasswordLogin: supportsPasswordLogin,
+                                                    elementWellKnown: requiresElementPro ? "{\"version\":1,\"enforce_element_pro\":true}" : nil))
         let configuration = AuthenticationClientFactoryMock.Configuration(homeserverClients: ["matrix.org": client])
         
         clientFactory = AuthenticationClientFactoryMock(configuration: configuration)
@@ -328,6 +347,7 @@ class ServerConfirmationScreenViewModelTests: XCTestCase {
         viewModel = ServerConfirmationScreenViewModel(authenticationService: service,
                                                       mode: mode,
                                                       authenticationFlow: authenticationFlow,
+                                                      appSettings: ServiceLocator.shared.settings,
                                                       userIndicatorController: UserIndicatorControllerMock())
         
         // Add a fake window in order for the OIDC flow to continue

UnitTests/Sources/ServerSelectionScreenViewModelTests.swift

@@ -87,6 +87,24 @@ class ServerSelectionScreenViewModelTests: XCTestCase {
         XCTAssertEqual(context.alertInfo?.id, .registrationAlert)
     }
     
+    func testElementProRequiredAlert() async throws {
+        // Given a view model for login.
+        setupViewModel(authenticationFlow: .login)
+        XCTAssertEqual(service.homeserver.value.loginMode, .unknown)
+        XCTAssertEqual(clientFactory.makeClientHomeserverAddressSessionDirectoriesPassphraseClientSessionDelegateAppSettingsAppHooksCallsCount, 0)
+        XCTAssertNil(context.alertInfo)
+        
+        // When selecting a server that requires Element Pro
+        context.homeserverAddress = "secure.gov"
+        let deferred = deferFulfillment(context.observe(\.alertInfo)) { $0 != nil }
+        context.send(viewAction: .confirm)
+        try await deferred.fulfill()
+        
+        // Then selection should fail with an alert telling the user to download Element Pro.
+        XCTAssertEqual(clientFactory.makeClientHomeserverAddressSessionDirectoriesPassphraseClientSessionDelegateAppSettingsAppHooksCallsCount, 1)
+        XCTAssertEqual(context.alertInfo?.id, .elementProAlert)
+    }
+    
     func testInvalidServer() async throws {
         // Given a new instance of the view model.
         setupViewModel(authenticationFlow: .login)
@@ -131,6 +149,7 @@ class ServerSelectionScreenViewModelTests: XCTestCase {
         
         viewModel = ServerSelectionScreenViewModel(authenticationService: service,
                                                    authenticationFlow: authenticationFlow,
+                                                   appSettings: ServiceLocator.shared.settings,
                                                    userIndicatorController: UserIndicatorControllerMock())
     }
 }