Try to handle state replacements

src/models/roommodel.cpp

@@ -40,6 +40,9 @@ template <class T> auto eventUserId(const mtx::events::RoomEvent<T> &e) -> std::
 template <class T> auto eventTimestamp(const mtx::events::Event<T> &e) -> uint64_t { return 0; }
 template <class T> auto eventTimestamp(const mtx::events::RoomEvent<T> &e) -> uint64_t { return e.origin_server_ts; }
 
+template <class T> auto eventStateKey(const mtx::events::Event<T> &e) -> std::string { return ""; }
+template <class T> auto eventStateKey(const mtx::events::StateEvent<T> &e) -> std::string { return e.state_key; }
+
 template <class T>::EventType::Type toRoomEventType(const Event<T> &e) {
     using mtx::events::EventType;
     switch (e.type) {
@@ -138,19 +141,31 @@ void Room::addEvents(std::vector<mtx::events::collections::TimelineEvents> event
     using namespace mtx::events;
     if (this->prev_batch == next_batch) {
         qDebug() << "New events at beginning of timeline";
-        int i = 0;
-        for (const auto &event : this->events) {
-            if (boost::apply_visitor([](const auto &e) -> uint64_t { return eventTimestamp(e); }, event) != 0)
-                break;
-            i++;
+        for (const auto &event : events) {
+            std::string state_key =
+                boost::apply_visitor([](const auto &e) -> std::string { return eventStateKey(e); }, event);
+            if (!state_key.empty() && stateKeys.count(state_key)) {
+                for (int i = 0; i < (int)this->events.size(); i++) {
+                    if (boost::apply_visitor([](const auto &e) -> std::string { return eventStateKey(e); },
+                                             this->events[i]) == state_key) {
+                        beginRemoveRows(QModelIndex(), i, i);
+                        this->events.erase(this->events.begin() + i);
+                        endRemoveRows();
+                        break;
+                    }
+                }
+            }
         }
 
-        beginInsertRows(QModelIndex(), (int)i, (int)events.size() + i - 1);
-        this->events.insert(this->events.begin() + i, events.begin(), events.end());
+        beginInsertRows(QModelIndex(), (int)0, (int)events.size() - 1);
+        this->events.insert(this->events.begin(), events.begin(), events.end());
         this->prev_batch = prev_batch;
         endInsertRows();
     } else {
         for (const mtx::events::collections::TimelineEvents &e : events) {
+            this->stateKeys.insert(
+                boost::apply_visitor([](const auto &e) -> std::string { return eventStateKey(e); }, e));
+
             if (const auto ev = boost::get<StateEvent<state::Aliases>>(&e)) {
                 if (this->canonical_alias.empty() && !ev->content.aliases.empty())
                     this->canonical_alias = ev->content.aliases.front();

src/models/roommodel.h

@@ -130,6 +130,7 @@ struct Room : public QAbstractListModel {
     std::vector<std::string> tags;
 
     std::set<std::string> members;
+    std::set<std::string> stateKeys;
     std::map<std::string, MemberInfo> memberInfos;
 
     void applyEvents(const std::vector<mtx::events::collections::TimelineEvents> &events, std::string prev_batch,