Line to indicate first unread message (#1147)

* First draft of unread line feature.

* Minor visual fix.

* Removed unnecessary ternary operator.

* Extended unread line functionality to work on minimised window or focusing another window.

* Fix for unread line not showing when last read message is hidden.

* Minor performance improvement. Fix for misbehaving event2order DB at application start.

* Fix for possible performance issues when user has joined a large number of rooms.

* Fix for breaking macos and clazy builds.

* Changed on windows focus function to refresh unread line if room is unread.

* Unread line is removed when user sends a message.

* Linting.

* Fixed unread line to work in standalone room windows.

* Switch isRoomUnread for index 0.

* Merged try/catch blocks.

* Fix for crash on opening a room invite.

* Call fullyReadEventId function when used instead of storing it and passing it through.

* Function that was meant to sync the unread line was relying on an async function, oops.

* Linting again.

* More linting...

* Minor changes.

1 files changed, 47 insertions, 0 deletions

diff --git a/src/timeline/TimelineModel.cpp b/src/timeline/TimelineModel.cpp

index b7122db1..eaf85b2a 100644
--- a/src/timeline/TimelineModel.cpp
+++ b/src/timeline/TimelineModel.cpp
@@ -427,6 +427,7 @@ TimelineModel::TimelineModel(TimelineViewManager *manager, QString room_id, QObj
         setPaginationInProgress(false);
         updateLastMessage();
     });
+    connect(&events, &EventStore::fetchedMore, this, &TimelineModel::checkAfterFetch);
     connect(&events,
             &EventStore::startDMVerification,
             this,
@@ -977,6 +978,7 @@ TimelineModel::addEvents(const mtx::responses::Timeline &timeline)
             emit encryptionChanged();
         }
     }
+
     updateLastMessage();
 }
 
@@ -1370,6 +1372,48 @@ TimelineModel::markEventsAsRead(const std::vector<QString> &event_ids)
     }
 }
 
+void
+TimelineModel::updateLastReadId(QString currentRoomId)
+{
+    if (currentRoomId == room_id_) {
+        last_event_id = cache::getFullyReadEventId(room_id_.toStdString());
+        auto lastVisibleEventIndexAndId =
+          cache::lastVisibleEvent(room_id_.toStdString(), last_event_id);
+        if (lastVisibleEventIndexAndId) {
+            fullyReadEventId_ = lastVisibleEventIndexAndId->second;
+            emit fullyReadEventIdChanged();
+        }
+    }
+}
+
+void
+TimelineModel::lastReadIdOnWindowFocus()
+{
+    /* this stops it from removing the line when focusing another window
+     * and from removing the line when refocusing nheko */
+    if (ChatPage::instance()->isRoomActive(room_id_) &&
+        cache::calculateRoomReadStatus(room_id_.toStdString())) {
+        updateLastReadId(room_id_);
+    }
+}
+
+/*
+ * if the event2order db didn't have the messages we needed when the room was opened
+ * try again after these new messages were fetched
+ */
+void
+TimelineModel::checkAfterFetch()
+{
+    if (fullyReadEventId_.empty()) {
+        auto lastVisibleEventIndexAndId =
+          cache::lastVisibleEvent(room_id_.toStdString(), last_event_id);
+        if (lastVisibleEventIndexAndId) {
+            fullyReadEventId_ = lastVisibleEventIndexAndId->second;
+            emit fullyReadEventIdChanged();
+        }
+    }
+}
+
 template<typename T>
 void
 TimelineModel::sendEncryptedMessage(mtx::events::RoomEvent<T> msg, mtx::events::EventType eventType)
@@ -1550,6 +1594,9 @@ TimelineModel::addPendingMessage(mtx::events::collections::TimelineEvents event)
       event);
 
     std::visit(SendMessageVisitor{this}, event);
+
+    fullyReadEventId_ = this->EventId;
+    emit fullyReadEventIdChanged();
 }
 
 void