Lab setting to load rooms at first unread message

Change-Id: I781e5a32d8557939c51387eadf1387cba0d3b149

matrix-sdk-android/src/main/java/org/matrix/android/sdk/api/session/room/timeline/Timeline.kt

@@ -66,6 +66,16 @@ interface Timeline {
      */
     fun setInitialEventId(eventId: String?)
 
+    /**
+     * Offset for the initial event, e.g. if we want to load the event just below said id
+     */
+    fun getInitialEventIdOffset(): Int
+
+    /**
+     * Set the offset for the initial event, e.g. if we want to load the event just below said id
+     */
+    fun setInitialEventIdOffset(offset: Int)
+
     /**
      * Check if the timeline can be enriched by paginating.
      * @param direction the direction to check in

matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/room/timeline/DefaultTimeline.kt

@@ -61,6 +61,7 @@ private const val MIN_FETCHING_COUNT = 30
 internal class DefaultTimeline(
         private val roomId: String,
         private var initialEventId: String? = null,
+        private var initialEventIdOffset: Int = 0,
         private val realmConfiguration: RealmConfiguration,
         private val taskExecutor: TaskExecutor,
         private val contextOfEventTask: GetContextOfEventTask,
@@ -145,7 +146,7 @@ internal class DefaultTimeline(
 
     override fun start() {
         if (isStarted.compareAndSet(false, true)) {
-            Timber.v("Start timeline for roomId: $roomId and eventId: $initialEventId")
+            Timber.v("Start timeline for roomId: $roomId and eventId: $initialEventId (offset $initialEventIdOffset)")
             timelineInput.listeners.add(this)
             BACKGROUND_HANDLER.post {
                 eventDecryptor.start()
@@ -195,7 +196,7 @@ internal class DefaultTimeline(
         if (isStarted.compareAndSet(true, false)) {
             isReady.set(false)
             timelineInput.listeners.remove(this)
-            Timber.v("Dispose timeline for roomId: $roomId and eventId: $initialEventId")
+            Timber.v("Dispose timeline for roomId: $roomId and eventId: $initialEventId (offset $initialEventIdOffset)")
             cancelableBag.cancel()
             BACKGROUND_HANDLER.removeCallbacksAndMessages(null)
             BACKGROUND_HANDLER.post {
@@ -217,6 +218,7 @@ internal class DefaultTimeline(
     override fun restartWithEventId(eventId: String?) {
         dispose()
         initialEventId = eventId
+        initialEventIdOffset = 0
         start()
         postSnapshot()
     }
@@ -229,6 +231,14 @@ internal class DefaultTimeline(
         initialEventId = eventId
     }
 
+    override fun getInitialEventIdOffset(): Int {
+        return initialEventIdOffset
+    }
+
+    override fun setInitialEventIdOffset(offset: Int) {
+        initialEventIdOffset = offset
+    }
+
     override fun getTimelineEventAtIndex(index: Int): TimelineEvent? {
         return builtEvents.getOrNull(index)
     }

vector/src/main/java/im/vector/app/features/home/room/detail/RoomDetailViewModel.kt

@@ -131,11 +131,16 @@ class RoomDetailViewModel @AssistedInject constructor(
         Timeline.Listener, ChatEffectManager.Delegate, CallProtocolsChecker.Listener {
 
     private val room = session.getRoom(initialState.roomId)!!
-    private val eventId = initialState.eventId
+    private val eventId = initialState.eventId ?: if (vectorPreferences.loadRoomAtFirstUnread()) room.roomSummary()?.readMarkerId else null
     private val invisibleEventsObservable = BehaviorRelay.create<RoomDetailAction.TimelineEventTurnsInvisible>()
     private val visibleEventsObservable = BehaviorRelay.create<RoomDetailAction.TimelineEventTurnsVisible>()
     private var timelineEvents = PublishRelay.create<List<TimelineEvent>>()
-    val timeline = timelineFactory.createTimeline(viewModelScope, room, eventId)
+    val timeline = timelineFactory.createTimeline(viewModelScope, room, eventId).apply {
+        // Target the event just below $eventId in case that it is the readMarkerId
+        if (initialState.eventId == null && eventId != null) {
+            setInitialEventIdOffset(-1)
+        }
+    }
 
     // Same lifecycle than the ViewModel (survive to screen rotation)
     val previewUrlRetriever = PreviewUrlRetriever(session, viewModelScope)
@@ -184,8 +189,10 @@ class RoomDetailViewModel @AssistedInject constructor(
         observeActiveRoomWidgets()
         observePowerLevel()
         room.getRoomSummaryLive()
-        viewModelScope.launch(Dispatchers.IO) {
+        if (!vectorPreferences.loadRoomAtFirstUnread()) {
-            tryOrNull { room.markAsRead(ReadService.MarkAsReadParams.READ_RECEIPT) }
+            viewModelScope.launch(Dispatchers.IO) {
+                tryOrNull { room.markAsRead(ReadService.MarkAsReadParams.READ_RECEIPT) }
+            }
         }
         // Inform the SDK that the room is displayed
         viewModelScope.launch(Dispatchers.IO) {
@@ -507,6 +514,9 @@ class RoomDetailViewModel @AssistedInject constructor(
             mostRecentDisplayedEvent?.root?.eventId?.also {
                 session.coroutineScope.launch(NonCancellable) {
                     tryOrNull { room.setReadMarker(it) }
+                    if (vectorPreferences.loadRoomAtFirstUnread()) {
+                        tryOrNull { room.setReadReceipt(it) }
+                    }
                 }
             }
             mostRecentDisplayedEvent = null
@@ -1312,10 +1322,10 @@ class RoomDetailViewModel @AssistedInject constructor(
     }
 
     private fun observeEventDisplayedActions() {
-        // We are buffering scroll events for one second
+        // We are buffering scroll events for half a second
         // and keep the most recent one to set the read receipt on.
         visibleEventsObservable
-                .buffer(1, TimeUnit.SECONDS)
+                .buffer(500, TimeUnit.MILLISECONDS)
                 .filter { it.isNotEmpty() }
                 .subscribeBy(onNext = { actions ->
                     val bufferedMostRecentDisplayedEvent = actions.maxByOrNull { it.event.displayIndex }?.event ?: return@subscribeBy

vector/src/main/java/im/vector/app/features/home/room/detail/ScrollOnNewMessageCallback.kt

@@ -23,6 +23,7 @@ import im.vector.app.features.home.room.detail.timeline.TimelineEventController
 import im.vector.app.features.home.room.detail.timeline.item.ItemWithEvents
 import org.matrix.android.sdk.api.extensions.tryOrNull
 import java.util.concurrent.CopyOnWriteArrayList
+import kotlin.math.max
 
 class ScrollOnNewMessageCallback(private val layoutManager: LinearLayoutManager,
                                  private val timelineEventController: TimelineEventController,
@@ -32,7 +33,6 @@ class ScrollOnNewMessageCallback(private val layoutManager: LinearLayoutManager,
     private var forceScroll = false
     var initialForceScroll = false
     var initialForceScrollEventId: String? = null
-        get() = field ?: timelineEventController.timeline?.getInitialEventId()
 
     fun addNewTimelineEventIds(eventIds: List<String>) {
         // Disable initial force scroll
@@ -57,8 +57,10 @@ class ScrollOnNewMessageCallback(private val layoutManager: LinearLayoutManager,
     override fun onInserted(position: Int, count: Int) {
         if (initialForceScroll) {
             var scrollToEvent = initialForceScrollEventId
+            var scrollOffset = 0
             if (initialForceScrollEventId == null) {
                 scrollToEvent = timelineEventController.timeline?.getInitialEventId()
+                scrollOffset = timelineEventController.timeline?.getInitialEventIdOffset() ?: 0
             }
             if (scrollToEvent == null) {
                 layoutManager.scrollToPositionWithOffset(0, 0)
@@ -67,7 +69,8 @@ class ScrollOnNewMessageCallback(private val layoutManager: LinearLayoutManager,
                     // Scroll such that the scrolled-to event is moved down 1/3 of the screen.
                     // To do that, we actually scroll the view above out by 2/3 (since we can only control the distance
                     // from the bottom of the view, not the top).
-                    layoutManager.scrollToPositionWithOffset(it + 1, parentView.measuredHeight * 2 / 3)
+                    val scrollToPosition = max(it + scrollOffset + 1, 0)
+                    layoutManager.scrollToPositionWithOffset(scrollToPosition, parentView.measuredHeight * 2 / 3)
                 }
             }
             return

vector/src/main/java/im/vector/app/features/settings/VectorPreferences.kt

@@ -203,6 +203,7 @@ class VectorPreferences @Inject constructor(private val context: Context) {
         private const val SETTINGS_USER_COLOR_MODE_DM = "SETTINGS_USER_COLOR_MODE_DM"
         private const val SETTINGS_USER_COLOR_MODE_DEFAULT = "SETTINGS_USER_COLOR_MODE_DEFAULT"
         private const val SETTINGS_USER_COLOR_MODE_PUBLIC_ROOM = "SETTINGS_USER_COLOR_MODE_PUBLIC_ROOM"
+        private const val SETTINGS_OPEN_CHATS_AT_FIRST_UNREAD = "SETTINGS_OPEN_CHATS_AT_FIRST_UNREAD"
 
         private const val DID_ASK_TO_ENABLE_SESSION_PUSH = "DID_ASK_TO_ENABLE_SESSION_PUSH"
 
@@ -997,6 +998,11 @@ class VectorPreferences @Inject constructor(private val context: Context) {
         }, MatrixItemColorProvider.USER_COLORING_DEFAULT) ?: MatrixItemColorProvider.USER_COLORING_DEFAULT
     }
 
+    // SC addition
+    fun loadRoomAtFirstUnread(): Boolean {
+        return defaultPrefs.getBoolean(SETTINGS_OPEN_CHATS_AT_FIRST_UNREAD, false)
+    }
+
     /**
      * The user enable protecting app access with pin code.
      * Currently we use the pin code store to know if the pin is enabled, so this is not used

vector/src/main/res/values/strings_sc.xml

@@ -84,6 +84,9 @@
     <string name="setting_sc_accent_color_dark">Accent color for dark themes</string>
     <string name="settings_sc_accent_disclaimer">Note that these color settings only apply to SC themes, and not Element themes.</string>
 
+    <string name="settings_open_chats_at_first_unread">Open at first unread</string>
+    <string name="settings_open_chats_at_first_unread_summary">Open chats at the first unread message instead of at the bottom.</string>
+
     <!-- Accent colors -->
     <string name="sc_accent_greenlight">Light green</string>
     <string name="sc_accent_greendark">Dark green</string>

vector/src/main/res/xml/vector_settings_labs.xml

@@ -34,6 +34,12 @@
     <!--android:summary="@string/settings_labs_enable_send_voice_summary"-->
     <!--android:title="@string/settings_labs_enable_send_voice" />-->
 
+    <im.vector.app.core.preference.VectorSwitchPreference
+        android:defaultValue="false"
+        android:key="SETTINGS_OPEN_CHATS_AT_FIRST_UNREAD"
+        android:title="@string/settings_open_chats_at_first_unread"
+        android:summary="@string/settings_open_chats_at_first_unread_summary" />
+
     <im.vector.app.core.preference.VectorSwitchPreference
         android:defaultValue="false"
         android:key="SYSTEM_DARK_THEME_PRE_TEN"