2 files changed, 32 insertions, 21 deletions

diff --git a/room.cpp b/room.cpp
index 85ab1720..366073c7 100644
--- a/room.cpp
+++ b/room.cpp
@@ -170,13 +170,14 @@ void Room::setLastReadEvent(User* user, QString eventId)
     emit lastReadEventChanged(user);
 }
 
-bool Room::promoteReadMarker(QString newLastReadEventId)
+Room::Timeline::const_iterator Room::promoteReadMarker(QString eventId)
 {
     User* localUser = connection()->user();
     QString prevLastReadId = lastReadEvent(localUser);
     int stillUnreadMessagesCount = 0;
+    auto it = d->messageEvents.end();
     // Older Qt doesn't provide rbegin()/rend() for Qt containers
-    for (auto it = messageEvents().end(); it != messageEvents().begin();)
+    while (it != d->messageEvents.begin())
     {
         --it;
         // Check that the new read event is not before the previously set - only
@@ -186,9 +187,10 @@ bool Room::promoteReadMarker(QString newLastReadEventId)
 
         // Found the message to mark as read; for the local user,
         // if we don't have other notable events below this one, reset unreadMessages
-        if (newLastReadEventId == (*it)->id())
+        if (eventId == (*it)->id())
         {
-            setLastReadEvent(localUser, newLastReadEventId);
+            setLastReadEvent(localUser, eventId);
+            emit readMarkerPromoted();
             break;
         }
 
@@ -205,15 +207,17 @@ bool Room::promoteReadMarker(QString newLastReadEventId)
     if (stillUnreadMessagesCount > 0)
         qDebug() << "Room" << displayName()
                  << ": still" << stillUnreadMessagesCount << "unread message(s)";
-    return newLastReadEventId.isEmpty() || lastReadEvent(localUser) == newLastReadEventId;
+    return it;
 }
 
-void Room::markMessagesAsRead(Timeline::const_iterator last)
+void Room::markMessagesAsRead(QString uptoEventId)
 {
-    QString prevLastReadId = lastReadEvent(connection()->user());
-    if ( !promoteReadMarker( (*last)->id()) )
+    if (d->messageEvents.empty())
         return;
 
+    QString prevLastReadId = lastReadEvent(connection()->user());
+    auto last = promoteReadMarker(uptoEventId);
+
     // We shouldn't send read receipts for messages from the local user - so
     // shift back (if necessary) to the nearest message not from the local user
     // or the so far last read message, whichever comes first.
@@ -221,7 +225,7 @@ void Room::markMessagesAsRead(Timeline::const_iterator last)
     {
         if ((*last)->senderId() != connection()->userId())
         {
-            d->connection->postReceipt(this, (*last));
+            d->connection->postReceipt(this, *last);
             break;
         }
         if (last == messageEvents().begin())
@@ -232,7 +236,7 @@ void Room::markMessagesAsRead(Timeline::const_iterator last)
 void Room::markMessagesAsRead()
 {
     if (!messageEvents().empty())
-        markMessagesAsRead(messageEvents().end() - 1);
+        markMessagesAsRead(messageEvents().back()->id());
 }
 
 bool Room::hasUnreadMessages()
@@ -240,11 +244,16 @@ bool Room::hasUnreadMessages()
     return d->unreadMessages;
 }
 
-QString Room::lastReadEvent(User* user)
+QString Room::lastReadEvent(User* user) const
 {
     return d->lastReadEvent.value(user);
 }
 
+QString Room::readMarkerEventId() const
+{
+    return lastReadEvent(d->connection->user());
+}
+
 int Room::notificationCount() const
 {
     return d->notificationCount;
diff --git a/room.h b/room.h
index 79c765ba..a518ae42 100644
--- a/room.h
+++ b/room.h
@@ -37,6 +37,7 @@ namespace QMatrixClient
     class Room: public QObject
     {
             Q_OBJECT
+            Q_PROPERTY(QString readMarkerEventId READ readMarkerEventId WRITE markMessagesAsRead NOTIFY readMarkerPromoted)
         public:
             using Timeline = Owning<Events>;
 
@@ -70,19 +71,19 @@ namespace QMatrixClient
             Q_INVOKABLE void updateData(SyncRoomData& data );
             Q_INVOKABLE void setJoinState( JoinState state );
 
-            Q_INVOKABLE QString lastReadEvent(User* user);
+            Q_INVOKABLE QString lastReadEvent(User* user) const;
+            QString readMarkerEventId() const;
             /**
-             * @brief Mark the message at the iterator as read
+             * @brief Mark the event with uptoEventId as read
              *
-             * Marks the message at the iterator as read; also posts a read
-             * receipt to the server either for this message or, if it's from
-             * the local user, for the nearest non-local message before.
+             * Finds in the timeline and marks as read the event with
+             * the specified id; also posts a read receipt to the server either
+             * for this message or, if it's from the local user, for
+             * the nearest non-local message before.
              */
-            Q_INVOKABLE void markMessagesAsRead(Timeline::const_iterator last);
+            Q_INVOKABLE void markMessagesAsRead(QString uptoEventId);
             /**
-             * @brief Mark the most recent message in the timeline as read
-             *
-             * This effectively marks everything in the room as read.
+             * @brief Mark the whole room timeline as read
              */
             Q_INVOKABLE void markMessagesAsRead();
 
@@ -121,6 +122,7 @@ namespace QMatrixClient
             void highlightCountChanged(Room* room);
             void notificationCountChanged(Room* room);
             void lastReadEventChanged(User* user);
+            void readMarkerPromoted();
             void unreadMessagesChanged(Room* room);
 
         protected:
@@ -130,7 +132,7 @@ namespace QMatrixClient
             virtual void processStateEvents(const Events& events);
             virtual void processEphemeralEvent(Event* event);
 
-            bool promoteReadMarker(QString newLastReadEventId);
+            Timeline::const_iterator promoteReadMarker(QString eventId);
 
         private:
             class Private;