work on labels management in feed fetch loop, there was hidden bug before, now possibly still broken, but atleast i found it and know what todo

src/librssguard/core/feeddownloader.cpp

@@ -331,16 +331,28 @@ void FeedDownloader::updateOneFeed(ServiceRoot* acc,
         }
 
         // Process changed labels.
+        //
+        // NOTE: We do not need to to this for
+        // feeds which do not use online synchronised
+        // labels, because those synchronized feeds
+        // replace all labels later in the method.
+        // const bool uses_online_labels =
+        //  (feed->getParentServiceRoot()->supportedLabelOperations() & ServiceRoot::LabelOperation::Synchronised) ==
+        //  ServiceRoot::LabelOperation::Synchronised;
+
+        // if (!uses_online_labels) {
+
+        // NOTE: We only remember what labels were added/removed in filters
+        // and store the fact to server (of synchronized) and local DB later.
+        // This is mainly because articles might not even be in DB yet.
+        // So first insert articles, then update their label assignments etc.
         for (Label* lbl : qAsConst(msg_original.m_assignedLabels)) {
           if (!msg_tweaked_by_filter->m_assignedLabels.contains(lbl)) {
             QMutexLocker lck(&m_mutexDb);
 
             // Label is not there anymore, it was deassigned.
-            lbl->deassignFromMessage(*msg_tweaked_by_filter);
+            msg_tweaked_by_filter->m_deassignedLabelsByFilter << lbl;
-
+            msg_tweaked_by_filter->m_assignedLabels << lbl;
-            qDebugNN << LOGSEC_FEEDDOWNLOADER << "It was detected that label" << QUOTE_W_SPACE(lbl->customId())
-                     << "was DEASSIGNED from message" << QUOTE_W_SPACE(msg_tweaked_by_filter->m_customId)
-                     << "by message filter(s).";
           }
         }
 
@@ -350,13 +362,11 @@ void FeedDownloader::updateOneFeed(ServiceRoot* acc,
 
             // Label is in new message, but is not in old message, it
             // was newly assigned.
-            lbl->assignToMessage(*msg_tweaked_by_filter);
+            msg_tweaked_by_filter->m_assignedLabelsByFilter << lbl;
-
+            msg_tweaked_by_filter->m_assignedLabels << lbl;
-            qDebugNN << LOGSEC_FEEDDOWNLOADER << "It was detected that label" << QUOTE_W_SPACE(lbl->customId())
-                     << "was ASSIGNED to message" << QUOTE_W_SPACE(msg_tweaked_by_filter->m_customId)
-                     << "by message filter(s).";
           }
         }
+        //}
 
         if (remove_msg) {
           msgs.removeAt(i--);

src/librssguard/core/message.cpp

@@ -67,6 +67,8 @@ Message::Message() {
   m_score = 0.0;
   m_isRead = m_isImportant = m_isDeleted = false;
   m_assignedLabels = QList<Label*>();
+  m_assignedLabelsByFilter = QList<Label*>();
+  m_deassignedLabelsByFilter = QList<Label*>();
 }
 
 void Message::sanitize(const Feed* feed, bool fix_future_datetimes) {

src/librssguard/core/message.h

@@ -67,6 +67,9 @@ class RSSGUARD_DLLSPEC Message {
     // List of custom IDs of labels assigned to this message.
     QList<Label*> m_assignedLabels;
 
+    QList<Label*> m_assignedLabelsByFilter;
+    QList<Label*> m_deassignedLabelsByFilter;
+
     // Is true if "created" date was obtained directly
     // from the feed, otherwise is false
     bool m_createdFromFeed = false;

src/librssguard/database/databasequeries.cpp

@@ -38,7 +38,7 @@ QMap<int, QString> DatabaseQueries::messageTableAttributes(bool only_msg_table)
                                            "ELSE 'false' "
                                            "END AS has_enclosures");
   field_names[MSG_DB_LABELS] =
-    QSL("(SELECT GROUP_CONCAT(Labels.name) FROM Labels WHERE Labels.id IN (SELECT "
+    QSL("(SELECT GROUP_CONCAT(Labels.name) FROM Labels WHERE Labels.custom_id IN (SELECT "
         "LabelsInMessages.label FROM LabelsInMessages WHERE LabelsInMessages.account_id = "
         "Messages.account_id AND LabelsInMessages.message = Messages.custom_id)) as msg_labels");
 
@@ -1439,19 +1439,33 @@ QPair<int, int> DatabaseQueries::updateMessages(QSqlDatabase db,
     }
   }
 
-  // Update labels assigned to message.
+  const bool uses_online_labels =
+    (feed->getParentServiceRoot()->supportedLabelOperations() & ServiceRoot::LabelOperation::Synchronised) ==
+    ServiceRoot::LabelOperation::Synchronised;
+
   for (Message& message : messages) {
-    if (!message.m_assignedLabels.isEmpty()) {
     if (!message.m_customId.isEmpty() || message.m_id > 0) {
       QMutexLocker lck(db_mutex);
+
+      if (uses_online_labels) {
+        // Store all labels obtained from server.
         setLabelsForMessage(db, message.m_assignedLabels, message);
       }
+
+      // Adjust labels tweaked by filters.
+      for (Label* assigned_by_filter : message.m_assignedLabelsByFilter) {
+        assigned_by_filter->assignToMessage(message);
+      }
+
+      for (Label* removed_by_filter : message.m_deassignedLabelsByFilter) {
+        removed_by_filter->deassignFromMessage(message);
+      }
+    }
     else {
       qCriticalNN << LOGSEC_DB << "Cannot set labels for message" << QUOTE_W_SPACE(message.m_title)
                   << "because we don't have ID or custom ID.";
     }
   }
-  }
 
   // Now, fixup custom IDS for messages which initially did not have them,
   // just to keep the data consistent.