Add support for Account Provisioning links. (#4108)

* Add support for account provisioning links and route them to the authentication flow.

* Use the provisioning parameters to configure the authentication flow.

* Add UI tests for the provisioned authentication flow.

* Record new preview snapshots.

* Add unit tests.

* Make the domain configurable in the app settings.

* Use the loginHint in the login screen too.

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

@@ -11,6 +11,8 @@ import SwiftUI
 struct LoginScreenCoordinatorParameters {
     /// The service used to authenticate the user.
     let authenticationService: AuthenticationServiceProtocol
+    /// An optional hint that can be used to pre-fill the form.
+    let loginHint: String?
     let userIndicatorController: UserIndicatorControllerProtocol
     let analytics: AnalyticsService
 }
@@ -42,6 +44,7 @@ final class LoginScreenCoordinator: CoordinatorProtocol {
         self.parameters = parameters
         
         viewModel = LoginScreenViewModel(authenticationService: parameters.authenticationService,
+                                         loginHint: parameters.loginHint,
                                          userIndicatorController: parameters.userIndicatorController,
                                          analytics: parameters.analytics)
     }

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

@@ -21,13 +21,21 @@ class LoginScreenViewModel: LoginScreenViewModelType, LoginScreenViewModelProtoc
     }
 
     init(authenticationService: AuthenticationServiceProtocol,
+         loginHint: String?,
          userIndicatorController: UserIndicatorControllerProtocol,
          analytics: AnalyticsService) {
         self.authenticationService = authenticationService
         self.userIndicatorController = userIndicatorController
         self.analytics = analytics
         
-        let viewState = LoginScreenViewState(homeserver: authenticationService.homeserver.value)
+        let username = switch loginHint {
+        case .some(let hint) where hint.hasPrefix("mxid:"): String(hint.dropFirst(5)) // MSC4198
+        case .some(let hint): hint
+        case .none: ""
+        }
+        
+        let viewState = LoginScreenViewState(homeserver: authenticationService.homeserver.value,
+                                             bindings: LoginScreenBindings(username: username))
         
         super.init(initialViewState: viewState)
         

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

@@ -161,6 +161,7 @@ struct LoginScreen_Previews: PreviewProvider, TestablePreview {
         Task { await authenticationService.configure(for: homeserverAddress, flow: .login) }
         
         let viewModel = LoginScreenViewModel(authenticationService: authenticationService,
+                                             loginHint: nil,
                                              userIndicatorController: UserIndicatorControllerMock(),
                                              analytics: ServiceLocator.shared.analytics)
         

ElementX/Sources/Screens/Authentication/OIDCAuthenticationPresenter.swift

@@ -15,6 +15,8 @@ class OIDCAuthenticationPresenter: NSObject {
     private let presentationAnchor: UIWindow
     private let userIndicatorController: UserIndicatorControllerProtocol
     
+    private var activeSession: ASWebAuthenticationSession?
+    
     init(authenticationService: AuthenticationServiceProtocol,
          oidcRedirectURL: URL,
          presentationAnchor: UIWindow,
@@ -36,9 +38,12 @@ class OIDCAuthenticationPresenter: NSObject {
             session.prefersEphemeralWebBrowserSession = false
             session.presentationContextProvider = self
             
+            activeSession = session
             session.start()
         }
         
+        activeSession = nil
+        
         guard let url else {
             // Check for user cancellation to avoid showing an alert in that instance.
             if let nsError = error as? NSError,
@@ -76,6 +81,10 @@ class OIDCAuthenticationPresenter: NSObject {
         }
     }
     
+    func cancel() {
+        activeSession?.cancel()
+    }
+    
     private static let loadingIndicatorID = "\(OIDCAuthenticationPresenter.self)-Loading"
     
     private func startLoading(delay: Duration? = nil) {

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

@@ -101,7 +101,7 @@ class ServerConfirmationScreenViewModel: ServerConfirmationScreenViewModelType,
         startLoading() // Uses the same ID, so no need to worry if the indicator already exists
         defer { stopLoading() }
         
-        switch await authenticationService.urlForOIDCLogin() {
+        switch await authenticationService.urlForOIDCLogin(loginHint: nil) {
         case .success(let oidcData):
             actionsSubject.send(.continueWithOIDC(data: oidcData, window: window))
         case .failure:

ElementX/Sources/Screens/Authentication/SoftLogoutScreen/SoftLogoutScreenCoordinator.swift

@@ -134,7 +134,7 @@ final class SoftLogoutScreenCoordinator: CoordinatorProtocol {
         startLoading()
         
         Task {
-            switch await authenticationService.urlForOIDCLogin() {
+            switch await authenticationService.urlForOIDCLogin(loginHint: nil) {
             case .failure(let error):
                 stopLoading()
                 handleError(error)