Show an icon in the room header for shared history (#6090)

Add a decoration to the header for encrypted rooms with `history_visibility:
{shared|public}`.

Fixes: #6070

---------

Co-authored-by: ElementBot <android@element.io>
Co-authored-by: Jorge Martín <jorgem@element.io>

features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/MessagesPresenter.kt

@@ -75,6 +75,7 @@ import io.element.android.libraries.matrix.api.permalink.PermalinkParser
 import io.element.android.libraries.matrix.api.room.JoinedRoom
 import io.element.android.libraries.matrix.api.room.RoomInfo
 import io.element.android.libraries.matrix.api.room.RoomMembersState
+import io.element.android.libraries.matrix.api.room.history.RoomHistoryVisibility
 import io.element.android.libraries.matrix.api.room.isDm
 import io.element.android.libraries.matrix.api.room.powerlevels.permissionsAsState
 import io.element.android.libraries.matrix.api.timeline.item.event.EventOrTransactionId
@@ -207,6 +208,16 @@ class MessagesPresenter(
         val dmRoomMember by room.getDirectRoomMember(membersState)
         val roomMemberIdentityStateChanges = identityChangeState.roomMemberIdentityStateChanges
 
+        val isKeyShareOnInviteEnabled by featureFlagService.isFeatureEnabledFlow(FeatureFlags.EnableKeyShareOnInvite).collectAsState(initial = false)
+        // The top bar should show a "history" icon if:
+        //   * History sharing is enabled,
+        //   * The room is encrypted, and:
+        //   * The room's history_visibility allows future users to see content.
+        val showSharedHistoryIcon = isKeyShareOnInviteEnabled &&
+            roomInfo.isEncrypted == true &&
+            (roomInfo.historyVisibility == RoomHistoryVisibility.Shared ||
+                roomInfo.historyVisibility == RoomHistoryVisibility.WorldReadable)
+
         LifecycleResumeEffect(dmRoomMember, roomInfo.isEncrypted) {
             if (roomInfo.isEncrypted == true) {
                 val dmRoomMemberId = dmRoomMember?.userId
@@ -290,6 +301,7 @@ class MessagesPresenter(
             pinnedMessagesBannerState = pinnedMessagesBannerState,
             dmUserVerificationState = dmUserVerificationState,
             roomMemberModerationState = roomMemberModerationState,
+            showSharedHistoryIcon = showSharedHistoryIcon,
             successorRoom = roomInfo.successorRoom,
             eventSink = ::handleEvent,
         )

features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/MessagesState.kt

@@ -56,6 +56,8 @@ data class MessagesState(
     val pinnedMessagesBannerState: PinnedMessagesBannerState,
     val dmUserVerificationState: IdentityState?,
     val roomMemberModerationState: RoomMemberModerationState,
+    /** Should the top bar include the "history" icon? */
+    val showSharedHistoryIcon: Boolean,
     val successorRoom: SuccessorRoom?,
     val eventSink: (MessagesEvent) -> Unit
 ) {

features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/MessagesStateProvider.kt

@@ -132,6 +132,7 @@ fun aMessagesState(
     pinnedMessagesBannerState: PinnedMessagesBannerState = aLoadedPinnedMessagesBannerState(),
     dmUserVerificationState: IdentityState? = null,
     roomMemberModerationState: RoomMemberModerationState = aRoomMemberModerationState(),
+    showSharedHistoryIcon: Boolean = false,
     successorRoom: SuccessorRoom? = null,
     eventSink: (MessagesEvent) -> Unit = {},
 ) = MessagesState(
@@ -160,6 +161,7 @@ fun aMessagesState(
     pinnedMessagesBannerState = pinnedMessagesBannerState,
     dmUserVerificationState = dmUserVerificationState,
     roomMemberModerationState = roomMemberModerationState,
+    showSharedHistoryIcon = showSharedHistoryIcon,
     successorRoom = successorRoom,
     eventSink = eventSink,
 )

features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/MessagesView.kt

@@ -226,6 +226,7 @@ fun MessagesView(
                             heroes = state.heroes,
                             roomCallState = state.roomCallState,
                             dmUserIdentityState = state.dmUserVerificationState,
+                            showSharedHistoryIcon = state.showSharedHistoryIcon,
                             onBackClick = { hidingKeyboard { onBackClick() } },
                             onRoomDetailsClick = { hidingKeyboard { onRoomDetailsClick() } },
                             onJoinCallClick = onJoinCallClick,

features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/topbars/MessagesViewTopBar.kt

@@ -63,6 +63,7 @@ internal fun MessagesViewTopBar(
     heroes: ImmutableList<AvatarData>,
     roomCallState: RoomCallState,
     dmUserIdentityState: IdentityState?,
+    showSharedHistoryIcon: Boolean,
     onRoomDetailsClick: () -> Unit,
     onJoinCallClick: () -> Unit,
     onBackClick: () -> Unit,
@@ -108,6 +109,14 @@ internal fun MessagesViewTopBar(
                     }
                     else -> Unit
                 }
+
+                if (showSharedHistoryIcon) {
+                    Icon(
+                        imageVector = CompoundIcons.History(),
+                        tint = ElementTheme.colors.iconInfoPrimary,
+                        contentDescription = stringResource(CommonStrings.common_shared_history),
+                    )
+                }
             }
         },
         actions = {
@@ -169,6 +178,7 @@ internal fun MessagesViewTopBarPreview() = ElementPreview {
         heroes: ImmutableList<AvatarData> = persistentListOf(),
         roomCallState: RoomCallState = RoomCallState.Unavailable,
         dmUserIdentityState: IdentityState? = null,
+        showSharedHistoryIcon: Boolean = false,
     ) = MessagesViewTopBar(
         roomName = roomName,
         roomAvatar = roomAvatar,
@@ -176,6 +186,7 @@ internal fun MessagesViewTopBarPreview() = ElementPreview {
         heroes = heroes,
         roomCallState = roomCallState,
         dmUserIdentityState = dmUserIdentityState,
+        showSharedHistoryIcon = showSharedHistoryIcon,
         onRoomDetailsClick = {},
         onJoinCallClick = {},
         onBackClick = {},
@@ -208,5 +219,11 @@ internal fun MessagesViewTopBarPreview() = ElementPreview {
             isTombstoned = true,
             dmUserIdentityState = IdentityState.VerificationViolation
         )
+        HorizontalDivider()
+        AMessagesViewTopBar(
+            roomName = "A DM with shared history",
+            dmUserIdentityState = IdentityState.Verified,
+            showSharedHistoryIcon = true,
+        )
     }
 }

features/messages/impl/src/test/kotlin/io/element/android/features/messages/impl/MessagesPresenterTest.kt

@@ -65,6 +65,7 @@ import io.element.android.libraries.matrix.api.room.MessageEventType
 import io.element.android.libraries.matrix.api.room.RoomMembersState
 import io.element.android.libraries.matrix.api.room.RoomMembershipState
 import io.element.android.libraries.matrix.api.room.StateEventType
+import io.element.android.libraries.matrix.api.room.history.RoomHistoryVisibility
 import io.element.android.libraries.matrix.api.room.tombstone.SuccessorRoom
 import io.element.android.libraries.matrix.api.timeline.Timeline
 import io.element.android.libraries.matrix.api.timeline.item.TimelineItemDebugInfo
@@ -1216,6 +1217,27 @@ class MessagesPresenterTest {
         }
     }
 
+    @Test
+    fun `present - shows a "history" icon if the room is encrypted and history is shared`() = runTest {
+        val presenter = createMessagesPresenter(
+            joinedRoom = FakeJoinedRoom(
+                baseRoom = FakeBaseRoom(
+                    roomPermissions = roomPermissions(),
+                    initialRoomInfo = aRoomInfo(isEncrypted = true, historyVisibility = RoomHistoryVisibility.Shared),
+                ),
+            ),
+            featureFlagService = FakeFeatureFlagService(
+                initialState = mapOf(FeatureFlags.EnableKeyShareOnInvite.key to true)
+            )
+        )
+        presenter.testWithLifecycleOwner {
+            awaitItem()
+            runCurrent()
+            val state = awaitItem()
+            assertThat(state.showSharedHistoryIcon).isTrue()
+        }
+    }
+
     private fun roomPermissions(
         canStartCall: Boolean = true,
         canRedactOther: Boolean = true,

libraries/ui-strings/src/main/res/values/localazy.xml

@@ -334,6 +334,7 @@ Reason: %1$s."</string>
   <string name="common_server_url">"Server URL"</string>
   <string name="common_settings">"Settings"</string>
   <string name="common_share_space">"Share space"</string>
+  <string name="common_shared_history">"New members see history"</string>
   <string name="common_shared_location">"Shared location"</string>
   <string name="common_shared_space">"Shared space"</string>
   <string name="common_signing_out">"Signing out"</string>