vector-im/element-x-ios/issues/31 - Implement simple SaS sesson verification

* vector-im/element-x-ios/issues/31 - Session verification unit and UI tests
* Fix ImageAnonymizer tests when running on Apple Silicon
* Rename SessionVerification to SessionVerificationScreen

ElementX/Sources/Screens/HomeScreen/HomeScreenCoordinator.swift

@@ -26,6 +26,7 @@ struct HomeScreenCoordinatorParameters {
 enum HomeScreenCoordinatorAction {
     case presentRoom(roomIdentifier: String)
     case presentSettings
+    case verifySession
 }
 
 final class HomeScreenCoordinator: Coordinator, Presentable {
@@ -66,19 +67,31 @@ final class HomeScreenCoordinator: Coordinator, Presentable {
                 self.callback?(.presentRoom(roomIdentifier: roomIdentifier))
             case .tapUserAvatar:
                 self.callback?(.presentSettings)
+            case .verifySession:
+                self.callback?(.verifySession)
             }
         }
         
         parameters.userSession.clientProxy
             .callbacks
             .receive(on: DispatchQueue.main)
-            .sink { [weak self] action in
-                switch action {
-                case .updatedRoomsList:
+            .sink { [weak self] callback in
+                if case .updatedRoomsList = callback {
                     self?.updateRoomsList()
                 }
             }.store(in: &cancellables)
         
+        parameters.userSession.callbacks
+            .receive(on: DispatchQueue.main)
+            .sink { [weak self] callback in
+                switch callback {
+                case .sessionVerificationNeeded:
+                    self?.viewModel.showSessionVerificationBanner()
+                case .didVerifySession:
+                    self?.viewModel.hideSessionVerificationBanner()
+                }
+            }.store(in: &cancellables)
+        
         updateRoomsList()
         
         Task {

ElementX/Sources/Screens/HomeScreen/HomeScreenModels.swift

@@ -20,18 +20,22 @@ import UIKit
 enum HomeScreenViewModelAction {
     case selectRoom(roomIdentifier: String)
     case tapUserAvatar
+    case verifySession
 }
 
 enum HomeScreenViewAction {
     case loadRoomData(roomIdentifier: String)
     case selectRoom(roomIdentifier: String)
     case tapUserAvatar
+    case verifySession
 }
 
 struct HomeScreenViewState: BindableState {
     var userDisplayName: String?
     var userAvatar: UIImage?
     
+    var showSessionVerificationBanner: Bool = false
+    
     var rooms: [HomeScreenRoom] = []
     
     var isLoadingRooms: Bool = false

ElementX/Sources/Screens/HomeScreen/HomeScreenViewModel.swift

@@ -27,7 +27,7 @@ class HomeScreenViewModel: HomeScreenViewModelType, HomeScreenViewModelProtocol
 
     private var roomSummaries: [RoomSummaryProtocol]? {
         didSet {
-            self.state.isLoadingRooms = (roomSummaries?.count ?? 0 == 0)
+            state.isLoadingRooms = (roomSummaries?.count ?? 0 == 0)
         }
     }
     
@@ -51,6 +51,8 @@ class HomeScreenViewModel: HomeScreenViewModelType, HomeScreenViewModelProtocol
             callback?(.selectRoom(roomIdentifier: roomIdentifier))
         case .tapUserAvatar:
             callback?(.tapUserAvatar)
+        case .verifySession:
+            callback?(.verifySession)
         }
     }
     
@@ -84,11 +86,19 @@ class HomeScreenViewModel: HomeScreenViewModelType, HomeScreenViewModelProtocol
     }
     
     func updateWithUserAvatar(_ avatar: UIImage) {
-        self.state.userAvatar = avatar
+        state.userAvatar = avatar
     }
     
     func updateWithUserDisplayName(_ displayName: String) {
-        self.state.userDisplayName = displayName
+        state.userDisplayName = displayName
+    }
+    
+    func showSessionVerificationBanner() {
+        state.showSessionVerificationBanner = true
+    }
+    
+    func hideSessionVerificationBanner() {
+        state.showSessionVerificationBanner = false
     }
     
     // MARK: - Private
@@ -105,7 +115,7 @@ class HomeScreenViewModel: HomeScreenViewModelType, HomeScreenViewModelProtocol
     private func buildOrUpdateRoomFromSummary(_ roomSummary: RoomSummaryProtocol) -> HomeScreenRoom {
         let lastMessage = lastMessageFromEventBrief(roomSummary.lastMessage)
         
-        guard var room = self.state.rooms.first(where: { $0.id == roomSummary.id }) else {
+        guard var room = state.rooms.first(where: { $0.id == roomSummary.id }) else {
             return HomeScreenRoom(id: roomSummary.id,
                                   displayName: roomSummary.displayName,
                                   topic: roomSummary.topic,

ElementX/Sources/Screens/HomeScreen/HomeScreenViewModelProtocol.swift

@@ -26,4 +26,7 @@ protocol HomeScreenViewModelProtocol {
     func updateWithUserAvatar(_ avatar: UIImage)
     func updateWithUserDisplayName(_ displayName: String)
     func updateWithRoomSummaries(_ roomSummaries: [RoomSummaryProtocol])
+    
+    func showSessionVerificationBanner()
+    func hideSessionVerificationBanner()
 }

ElementX/Sources/Screens/HomeScreen/View/HomeScreen.swift

@@ -23,13 +23,27 @@ struct HomeScreen: View {
     // MARK: Views
     
     var body: some View {
-        VStack(spacing: 16.0) {
+        VStack(spacing: 0.0) {
             if context.viewState.isLoadingRooms {
                 VStack {
                     Text(ElementL10n.loading)
                     ProgressView()
                 }
             } else {
+                
+                if context.viewState.showSessionVerificationBanner {
+                    HStack {
+                        Text(ElementL10n.verificationVerifyDevice)
+                        Spacer()
+                        Button(ElementL10n.startVerification) {
+                            context.send(viewAction: .verifySession)
+                        }
+                    }
+                    .padding()
+                    .background(Color.element.quaternaryContent)
+                    .padding(.top, 1)
+                }
+                
                 List {
                     Section(ElementL10n.rooms) {
                         ForEach(context.viewState.visibleRooms) { room in
@@ -52,6 +66,8 @@ struct HomeScreen: View {
             Spacer()
         }
         .background(Color.element.background)
+        .transition(.slide)
+        .animation(.default, value: context.viewState.showSessionVerificationBanner)
         .ignoresSafeArea(.all, edges: .bottom)
         .navigationBarTitleDisplayMode(.inline)
         .toolbar {
@@ -100,6 +116,8 @@ struct HomeScreen: View {
 
 struct RoomCell: View {
     
+    @ScaledMetric private var avatarSize = 32.0
+    
     let room: HomeScreenRoom
     let context: HomeScreenViewModel.Context
     
@@ -112,12 +130,12 @@ struct RoomCell: View {
                     Image(uiImage: avatar)
                         .resizable()
                         .scaledToFill()
-                        .frame(width: 40, height: 40)
+                        .frame(width: avatarSize, height: avatarSize)
                         .clipShape(Circle())
                 } else {
                     PlaceholderAvatarImage(text: room.displayName ?? room.id)
                         .clipShape(Circle())
-                        .frame(width: 40, height: 40)
+                        .frame(width: avatarSize, height: avatarSize)
                 }
                 
                 VStack(alignment: .leading, spacing: 2.0) {
@@ -182,6 +200,8 @@ struct HomeScreen_Previews: PreviewProvider {
             viewModel.updateWithUserAvatar(avatarImage)
         }
         
+        viewModel.showSessionVerificationBanner()
+        
         return NavigationView {
             HomeScreen(context: viewModel.context)
         }