trim chat to last 30 blocks on initial load and session switch

gui/chatblockmodel.cpp

@@ -73,6 +73,17 @@ void ChatBlockModel::reset()
     emit countChanged();
 }
 
+void ChatBlockModel::trimFront(int keepCount)
+{
+    if (m_blocks.size() <= keepCount)
+        return;
+    int removeCount = m_blocks.size() - keepCount;
+    beginRemoveRows(QModelIndex(), 0, removeCount - 1);
+    m_blocks.remove(0, removeCount);
+    endRemoveRows();
+    emit countChanged();
+}
+
 void ChatBlockModel::processLine(const QString &line)
 {
     QRegularExpressionMatch m = s_headerRe.match(line);

gui/chatblockmodel.h

@@ -43,6 +43,7 @@ public:
 
     Q_INVOKABLE void appendData(const QString &text);
     Q_INVOKABLE void reset();
+    Q_INVOKABLE void trimFront(int keepCount);
 
 signals:
     void countChanged();

gui/main.qml

@@ -61,7 +61,10 @@ ApplicationWindow {
 
     Component.onCompleted: {
         var log = ollie.readLog()
-        if (log) chatModel.appendData(log)
+        if (log) {
+            chatModel.appendData(log)
+            chatModel.trimFront(30)
+        }
     }
 
     Connections {
@@ -69,7 +72,10 @@ ApplicationWindow {
         function onActiveSessionIdChanged() {
             chatModel.reset()
             var log = ollie.readLog()
-            if (log) chatModel.appendData(log)
+            if (log) {
+                chatModel.appendData(log)
+                chatModel.trimFront(30)
+            }
         }
         function onStreamingDone() {
             chatModel.appendData("\n[info]\nsession ended\n")