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/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")
     }
 }