Add a banner to encrypted rooms with visible history. (#4738)

* feat: Add history visible alert.

- Adds a dismissable alert that is displayed whenever the user
  opens a room with `history_visibility` != `joined`. When cleared,
  this is recorded in the app's data store.
- When opening a room with `history_visibility` = `joined`, this
  flag is cleared.

Issue: element-hq/element-meta#2875

* tests: Add unit tests for history sharing in `RoomScreenFooterView`.

* feat: Rename flag to `hasSeenHistoryVisibleBannerRooms`, document.

* refactor: Merge enum variants, use function for banner description.

* feat: Use `AppSettings.historyVisibleDetailsURL` over hard-coded value.

* tests: Correct potential race condition with deferred assertion.

* chore: Use Localazy translation string over project-defined.

* fix: Final tweaks and review comments.

* chore: Checkout `Enterprise` submodule.

* tests: Final fixes.

ElementX/Sources/Application/Settings/AppSettings.swift

@@ -32,6 +32,7 @@ final class AppSettings {
         case seenInvites
         case hasSeenSpacesAnnouncement
         case hasSeenNewSoundBanner
+        case acknowledgedHistoryVisibleRooms
         case appLockNumberOfPINAttempts
         case appLockNumberOfBiometricAttempts
         case timelineStyle
@@ -125,6 +126,7 @@ final class AppSettings {
                   deviceVerificationURL: URL,
                   chatBackupDetailsURL: URL,
                   identityPinningViolationDetailsURL: URL,
+                  historyVisibleDetailsURL: URL,
                   elementWebHosts: [String],
                   accountProvisioningHost: String,
                   bugReportApplicationID: String,
@@ -144,6 +146,7 @@ final class AppSettings {
         self.deviceVerificationURL = deviceVerificationURL
         self.chatBackupDetailsURL = chatBackupDetailsURL
         self.identityPinningViolationDetailsURL = identityPinningViolationDetailsURL
+        self.historyVisibleDetailsURL = historyVisibleDetailsURL
         self.elementWebHosts = elementWebHosts
         self.accountProvisioningHost = accountProvisioningHost
         self.bugReportApplicationID = bugReportApplicationID
@@ -171,6 +174,10 @@ final class AppSettings {
     @UserPreference(key: UserDefaultsKeys.hasSeenNewSoundBanner, defaultValue: true, storageType: .userDefaults(store))
     var hasSeenNewSoundBanner
     
+    /// The Set of room identifiers that the user has acknowledged have visible history.
+    @UserPreference(key: UserDefaultsKeys.acknowledgedHistoryVisibleRooms, defaultValue: [], storageType: .userDefaults(store))
+    var acknowledgedHistoryVisibleRooms: Set<String>
+    
     /// The initial set of account providers shown to the user in the authentication flow.
     ///
     /// Account provider is the friendly term for the server name. It should not contain an `https` prefix and should
@@ -202,6 +209,8 @@ final class AppSettings {
     private(set) var chatBackupDetailsURL: URL = "https://element.io/help#encryption5"
     /// A URL where users can go read more about identity pinning violations
     private(set) var identityPinningViolationDetailsURL: URL = "https://element.io/help#encryption18"
+    /// A URL where users can go to read more about room history sharing.
+    private(set) var historyVisibleDetailsURL: URL = "https://element.io/en/help#e2ee-history-sharing"
     /// Any domains that Element web may be hosted on - used for handling links.
     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.

ElementX/Sources/Screens/RoomScreen/RoomScreenModels.swift

@@ -93,11 +93,13 @@ struct RoomScreenViewStateBindings {
 enum RoomScreenFooterViewAction {
     case resolvePinViolation(userID: String)
     case resolveVerificationViolation(userID: String)
+    case dismissHistoryVisibleAlert
 }
 
 enum RoomScreenFooterViewDetails {
     case pinViolation(member: RoomMemberProxyProtocol, learnMoreURL: URL)
     case verificationViolation(member: RoomMemberProxyProtocol, learnMoreURL: URL)
+    case historyVisible(learnMoreURL: URL)
 }
 
 enum PinnedEventsBannerState: Equatable {

ElementX/Sources/Screens/RoomScreen/RoomScreenViewModel.swift

@@ -101,6 +101,9 @@ class RoomScreenViewModel: RoomScreenViewModelType, RoomScreenViewModelProtocol
                 Task { await resolveIdentityPinningViolation(userID) }
             case .resolveVerificationViolation(let userID):
                 Task { await resolveIdentityVerificationViolation(userID) }
+            case .dismissHistoryVisibleAlert:
+                appSettings.acknowledgedHistoryVisibleRooms.insert(roomProxy.id)
+                state.footerDetails = nil
             }
         case .acceptKnock(let eventID):
             Task { await acceptKnock(eventID: eventID) }
@@ -342,6 +345,16 @@ class RoomScreenViewModel: RoomScreenViewModelType, RoomScreenViewModelProtocol
             state.canDeclineKnocks = powerLevels.canOwnUserKick()
             state.canBan = powerLevels.canOwnUserBan()
         }
+        
+        // Whever the user opens a room with joined history visibility, we clear the dismiss flag to ensure that the banner is displayed again if the history is made visible in the future.
+        if roomInfo.historyVisibility == RoomHistoryVisibility.joined {
+            appSettings.acknowledgedHistoryVisibleRooms.remove(roomInfo.id)
+            state.footerDetails = nil
+        }
+        // Whenever the user opens an encrypted room with non-join history visbility, we show them a warning banner if they have not already dismissed it.
+        else if roomInfo.isEncrypted, !appSettings.acknowledgedHistoryVisibleRooms.contains(roomInfo.id) {
+            state.footerDetails = .historyVisible(learnMoreURL: appSettings.historyVisibleDetailsURL)
+        }
     }
     
     private func setupPinnedEventsTimelineItemProviderIfNeeded() {

ElementX/Sources/Screens/RoomScreen/View/RoomScreenFooterView.swift

@@ -16,7 +16,7 @@ struct RoomScreenFooterView: View {
     
     private var borderColor: Color {
         switch details {
-        case .pinViolation:
+        case .pinViolation, .historyVisible:
             .compound.borderInfoSubtle
         case .verificationViolation:
             .compound.borderCriticalSubtle
@@ -27,7 +27,7 @@ struct RoomScreenFooterView: View {
     
     private var gradient: Gradient {
         switch details {
-        case .pinViolation:
+        case .pinViolation, .historyVisible:
             .compound.info
         case .verificationViolation:
             Gradient(colors: [.compound.bgCriticalSubtle, .clear])
@@ -54,6 +54,8 @@ struct RoomScreenFooterView: View {
             pinViolation(member: member, learnMoreURL: learnMoreURL)
         case .verificationViolation(member: let member, learnMoreURL: let learnMoreURL):
             verificationViolation(member: member, learnMoreURL: learnMoreURL)
+        case .historyVisible(learnMoreURL: let learnMoreURL):
+            historyVisibleAlert(learnMoreURL: learnMoreURL)
         }
     }
     
@@ -151,10 +153,43 @@ struct RoomScreenFooterView: View {
         return description
     }
     
+    private func historyVisibleAlertDescriptionWithLearnMoreLink(learnMoreURL: URL) -> AttributedString {
+        let linkPlaceholder = "{link}"
+        var description = AttributedString(L10n.cryptoHistoryVisible(linkPlaceholder))
+        var linkString = AttributedString(L10n.actionLearnMore)
+        linkString.link = learnMoreURL
+        linkString.bold()
+        description.replace(linkPlaceholder, with: linkString)
+        return description
+    }
+    
     private func fallbackDisplayName(_ userID: String) -> String {
         guard let localpart = userID.components(separatedBy: ":").first else { return userID }
         return String(localpart.trimmingPrefix("@"))
     }
+    
+    private func historyVisibleAlert(learnMoreURL: URL) -> some View {
+        let description = historyVisibleAlertDescriptionWithLearnMoreLink(learnMoreURL: learnMoreURL)
+        
+        return VStack(spacing: 16) {
+            HStack(spacing: 16) {
+                CompoundIcon(\.info).foregroundColor(.compound.iconInfoPrimary)
+                Text(description)
+                    .font(.compound.bodyMD)
+                    .foregroundColor(.compound.textInfoPrimary)
+            }
+            Button {
+                callback(.dismissHistoryVisibleAlert)
+            } label: {
+                Text(L10n.actionDismiss)
+                    .frame(maxWidth: .infinity)
+            }
+            .buttonStyle(.compound(.primary, size: .medium))
+        }
+        .padding(.top, 16)
+        .padding(.horizontal, 16)
+        .padding(.bottom, 8)
+    }
 }
 
 struct RoomScreenFooterView_Previews: PreviewProvider, TestablePreview {
@@ -166,6 +201,8 @@ struct RoomScreenFooterView_Previews: PreviewProvider, TestablePreview {
     static let verificationViolationDetails: RoomScreenFooterViewDetails = .verificationViolation(member: RoomMemberProxyMock.mockBob,
                                                                                                   learnMoreURL: "https://element.io/")
     
+    static let historyVisibleDetails: RoomScreenFooterViewDetails = .historyVisible(learnMoreURL: "https://element.io")
+    
     static var previews: some View {
         RoomScreenFooterView(details: bobDetails, mediaProvider: MediaProviderMock(configuration: .init())) { _ in }
             .previewDisplayName("With displayname")
@@ -173,5 +210,6 @@ struct RoomScreenFooterView_Previews: PreviewProvider, TestablePreview {
             .previewDisplayName("Without displayname")
         RoomScreenFooterView(details: verificationViolationDetails, mediaProvider: MediaProviderMock(configuration: .init())) { _ in }
             .previewDisplayName("Verification Violation")
+        RoomScreenFooterView(details: historyVisibleDetails, mediaProvider: MediaProviderMock(configuration: .init())) { _ in }.previewDisplayName("History Visible")
     }
 }

ElementX/Sources/UITests/UITestsAppCoordinator.swift

@@ -140,6 +140,7 @@ class MockScreen: Identifiable {
                                      deviceVerificationURL: appSettings.deviceVerificationURL,
                                      chatBackupDetailsURL: appSettings.chatBackupDetailsURL,
                                      identityPinningViolationDetailsURL: appSettings.identityPinningViolationDetailsURL,
+                                     historyVisibleDetailsURL: appSettings.historyVisibleDetailsURL,
                                      elementWebHosts: appSettings.elementWebHosts,
                                      accountProvisioningHost: appSettings.accountProvisioningHost,
                                      bugReportApplicationID: appSettings.bugReportApplicationID,

UnitTests/Sources/AuthenticationStartScreenViewModelTests.swift

@@ -172,6 +172,7 @@ class AuthenticationStartScreenViewModelTests: XCTestCase {
                              deviceVerificationURL: appSettings.deviceVerificationURL,
                              chatBackupDetailsURL: appSettings.chatBackupDetailsURL,
                              identityPinningViolationDetailsURL: appSettings.identityPinningViolationDetailsURL,
+                             historyVisibleDetailsURL: appSettings.historyVisibleDetailsURL,
                              elementWebHosts: appSettings.elementWebHosts,
                              accountProvisioningHost: appSettings.accountProvisioningHost,
                              bugReportApplicationID: appSettings.bugReportApplicationID,

UnitTests/Sources/RoomScreenViewModelTests.swift

@@ -438,4 +438,118 @@ class RoomScreenViewModelTests: XCTestCase {
         }
         try await deferred.fulfill()
     }
+
+    // MARK: History Sharing
+
+    func testHistoryVisibleBannerDoesNotAppearIfNotEncrypted() async throws {
+        let roomProxyMock = JoinedRoomProxyMock(.init(isEncrypted: false))
+
+        let viewModel = RoomScreenViewModel(userSession: UserSessionMock(.init()),
+                                            roomProxy: roomProxyMock,
+                                            initialSelectedPinnedEventID: nil,
+                                            ongoingCallRoomIDPublisher: .init(.init(nil)),
+                                            appSettings: ServiceLocator.shared.settings,
+                                            appHooks: AppHooks(),
+                                            analyticsService: ServiceLocator.shared.analytics,
+                                            userIndicatorController: ServiceLocator.shared.userIndicatorController)
+
+        self.viewModel = viewModel
+
+        let deferred = deferFulfillment(viewModel.context.$viewState) { state in
+            state.footerDetails == nil
+        }
+        try await deferred.fulfill()
+    }
+
+    func testHistoryVisibleBannerDoesNotAppearIfJoined() async throws {
+        let configuration = JoinedRoomProxyMockConfiguration(isEncrypted: false)
+        let roomProxyMock = JoinedRoomProxyMock(configuration)
+
+        let roomInfoProxyMock = RoomInfoProxyMock(configuration)
+        roomInfoProxyMock.historyVisibility = .joined
+
+        let infoSubject = CurrentValueSubject<RoomInfoProxyProtocol, Never>(roomInfoProxyMock)
+        roomProxyMock.underlyingInfoPublisher = infoSubject.asCurrentValuePublisher()
+
+        let viewModel = RoomScreenViewModel(userSession: UserSessionMock(.init()),
+                                            roomProxy: roomProxyMock,
+                                            initialSelectedPinnedEventID: nil,
+                                            ongoingCallRoomIDPublisher: .init(.init(nil)),
+                                            appSettings: ServiceLocator.shared.settings,
+                                            appHooks: AppHooks(),
+                                            analyticsService: ServiceLocator.shared.analytics,
+                                            userIndicatorController: ServiceLocator.shared.userIndicatorController)
+
+        self.viewModel = viewModel
+
+        let deferred = deferFulfillment(viewModel.context.$viewState) { state in
+            state.footerDetails == nil
+        }
+        try await deferred.fulfill()
+    }
+
+    func testHistoryVisibleBannerDoesNotAppearIfAcknowledged() async throws {
+        ServiceLocator.shared.settings.acknowledgedHistoryVisibleRooms.insert("$room:example.com")
+
+        let configuration = JoinedRoomProxyMockConfiguration(id: "$room:example.com", isEncrypted: false)
+        let roomProxyMock = JoinedRoomProxyMock(configuration)
+
+        let roomInfoProxyMock = RoomInfoProxyMock(configuration)
+        roomInfoProxyMock.historyVisibility = .shared
+
+        let infoSubject = CurrentValueSubject<RoomInfoProxyProtocol, Never>(roomInfoProxyMock)
+        roomProxyMock.underlyingInfoPublisher = infoSubject.asCurrentValuePublisher()
+
+        let viewModel = RoomScreenViewModel(userSession: UserSessionMock(.init()),
+                                            roomProxy: roomProxyMock,
+                                            initialSelectedPinnedEventID: nil,
+                                            ongoingCallRoomIDPublisher: .init(.init(nil)),
+                                            appSettings: ServiceLocator.shared.settings,
+                                            appHooks: AppHooks(),
+                                            analyticsService: ServiceLocator.shared.analytics,
+                                            userIndicatorController: ServiceLocator.shared.userIndicatorController)
+
+        self.viewModel = viewModel
+
+        let deferred = deferFulfillment(viewModel.context.$viewState) { state in
+            state.footerDetails == nil
+        }
+        try await deferred.fulfill()
+    }
+
+    func testHistoryVisibleBannerAppearsThenDisappearsOnAcknowledge() async throws {
+        let configuration = JoinedRoomProxyMockConfiguration(id: "$room:example.com", isEncrypted: true)
+        let roomProxyMock = JoinedRoomProxyMock(configuration)
+
+        let roomInfoProxyMock = RoomInfoProxyMock(configuration)
+        roomInfoProxyMock.historyVisibility = .shared
+
+        let infoSubject = CurrentValueSubject<RoomInfoProxyProtocol, Never>(roomInfoProxyMock)
+        roomProxyMock.underlyingInfoPublisher = infoSubject.asCurrentValuePublisher()
+
+        let viewModel = RoomScreenViewModel(userSession: UserSessionMock(.init()),
+                                            roomProxy: roomProxyMock,
+                                            initialSelectedPinnedEventID: nil,
+                                            ongoingCallRoomIDPublisher: .init(.init(nil)),
+                                            appSettings: ServiceLocator.shared.settings,
+                                            appHooks: AppHooks(),
+                                            analyticsService: ServiceLocator.shared.analytics,
+                                            userIndicatorController: ServiceLocator.shared.userIndicatorController)
+
+        self.viewModel = viewModel
+
+        var deferred = deferFulfillment(viewModel.context.$viewState) { state in
+            state.footerDetails != nil
+        }
+        try await deferred.fulfill()
+
+        deferred = deferFulfillment(viewModel.context.$viewState) { state in
+            state.footerDetails == nil
+        }
+        
+        ServiceLocator.shared.settings.acknowledgedHistoryVisibleRooms.insert("$room:example.com")
+        viewModel.context.send(viewAction: .footerViewAction(RoomScreenFooterViewAction.dismissHistoryVisibleAlert))
+        
+        try await deferred.fulfill()
+    }
 }

UnitTests/Sources/ServerConfirmationScreenViewModelTests.swift

@@ -324,6 +324,7 @@ class ServerConfirmationScreenViewModelTests: XCTestCase {
                                  deviceVerificationURL: appSettings.deviceVerificationURL,
                                  chatBackupDetailsURL: appSettings.chatBackupDetailsURL,
                                  identityPinningViolationDetailsURL: appSettings.identityPinningViolationDetailsURL,
+                                 historyVisibleDetailsURL: appSettings.historyVisibleDetailsURL,
                                  elementWebHosts: appSettings.elementWebHosts,
                                  accountProvisioningHost: appSettings.accountProvisioningHost,
                                  bugReportApplicationID: appSettings.bugReportApplicationID,