ChatScene now properly react on aboutToRemoveRows(), which should improve stability...

[quassel.git] / src / qtui / chatscene.cpp

diff --git a/src/qtui/chatscene.cpp b/src/qtui/chatscene.cpp
index cb06e74..05d26c5 100644 (file)
--- a/src/qtui/chatscene.cpp
+++ b/src/qtui/chatscene.cpp
@@ -46,7 +46,7 @@ ChatScene::ChatScene(QAbstractItemModel *model, const QString &idString, QObject
     _selectingItem(0),
     _selectionStart(-1),
     _isSelecting(false),
-    _fetchingBacklog(false)
+    _lastBacklogSize(0)
 {
   MessageFilter *filter = qobject_cast<MessageFilter*>(model);
   if(filter) {
@@ -55,8 +55,11 @@ ChatScene::ChatScene(QAbstractItemModel *model, const QString &idString, QObject
 
   connect(this, SIGNAL(sceneRectChanged(const QRectF &)), this, SLOT(rectChanged(const QRectF &)));
 
-  connect(model, SIGNAL(rowsInserted(const QModelIndex &, int, int)), this, SLOT(rowsInserted(const QModelIndex &, int, int)));
-  connect(model, SIGNAL(modelAboutToBeReset()), this, SLOT(modelReset()));
+  connect(model, SIGNAL(rowsInserted(const QModelIndex &, int, int)),
+         this, SLOT(rowsInserted(const QModelIndex &, int, int)));
+  connect(model, SIGNAL(rowsAboutToBeRemoved(const QModelIndex &, int, int)),
+         this, SLOT(rowsAboutToBeRemoved(const QModelIndex &, int, int)));
+  
   for(int i = 0; i < model->rowCount(); i++) {
     ChatLine *line = new ChatLine(i, model);
     _lines.append(line);
@@ -87,7 +90,6 @@ ChatScene::ChatScene(QAbstractItemModel *model, const QString &idString, QObject
 }
 
 ChatScene::~ChatScene() {
-
 }
 
 void ChatScene::rowsInserted(const QModelIndex &index, int start, int end) {
@@ -97,7 +99,9 @@ void ChatScene::rowsInserted(const QModelIndex &index, int start, int end) {
   // TODO bulk inserts, iterators
   qreal h = 0;
   qreal y = 0;
-  if(_width && start > 0) y = _lines.value(start - 1)->y() + _lines.value(start - 1)->height();
+  if(_width && start > 0)
+    y = _lines.value(start - 1)->y() + _lines.value(start - 1)->height();
+
   for(int i = start; i <= end; i++) {
     ChatLine *line = new ChatLine(i, model());
     _lines.insert(i, line);
@@ -124,22 +128,56 @@ void ChatScene::rowsInserted(const QModelIndex &index, int start, int end) {
   if(h > 0) {
     _height += h;
     for(int i = end+1; i < _lines.count(); i++) {
-      _lines.value(i)->moveBy(0, h);
+      _lines.at(i)->moveBy(0, h);
     }
     setSceneRect(QRectF(0, 0, _width, _height));
     emit heightChanged(_height);
   }
-
-  requestBacklogIfNeeded();
 }
 
-void ChatScene::modelReset() {
-  foreach(ChatLine *line, _lines) {
-    removeItem(line);
-    delete line;
+void ChatScene::rowsAboutToBeRemoved(const QModelIndex &parent, int start, int end) {
+  Q_UNUSED(parent);
+
+  qreal h = 0; // total height of removed items;
+
+  // remove items from scene
+  QList<ChatLine *>::iterator lineIter = _lines.begin() + start;
+  int lineCount = start;
+  while(lineIter != _lines.end() && lineCount <= end) {
+    h += (*lineIter)->height();
+    delete *lineIter;
+    lineIter = _lines.erase(lineIter);
+    lineCount++;
+  }
+
+  // update rows of remaining chatlines
+  for(int i = start; i < _lines.count(); i++) {
+    _lines.at(i)->setRow(i);
+  }
+
+  // update selection
+  if(_selectionStart >= 0) {
+    int offset = end - start + 1;
+    if(_selectionStart >= start)
+      _selectionStart -= offset;
+    if(_selectionEnd >= start)
+      _selectionEnd -= offset;
+    if(_firstSelectionRow >= start)
+      _firstSelectionRow -= offset;
+    if(_lastSelectionRow >= start)
+      _lastSelectionRow -= offset;
+  }
+
+  // reposition remaining chatlines
+  if(h > 0) {
+    Q_ASSERT(_height >= h);
+    _height -= h;
+    for(int i = start; i < _lines.count(); i++) {
+      _lines.at(i)->moveBy(0, -h);
+    }
+    setSceneRect(QRectF(0, 0, _width, _height));
+    emit heightChanged(_height);
   }
-  _lines.clear();
-  setSceneRect(QRectF(0, 0, _width, 0));
 }
 
 void ChatScene::setWidth(qreal w) {
@@ -239,6 +277,8 @@ void ChatScene::updateSelection(const QPointF &pos) {
   if(newstart == newend && minColumn == ChatLineModel::ContentsColumn) {
     _lines[curRow]->setSelected(false);
     _isSelecting = false;
+    Q_ASSERT(_selectingItem); // this seems to not always be true, but I have no idea why
+                              // adding this assert to make sure the occasional segfault is caused by this
     _selectingItem->continueSelecting(_selectingItem->mapFromScene(pos));
   }
 }
@@ -305,27 +345,15 @@ QString ChatScene::selectionToString() const {
   return result;
 }
 
-void ChatScene::setIsFetchingBacklog(bool fetch) {
-  if(!isBacklogFetchingEnabled()) return;
-
-  if(!fetch) {
-    _fetchingBacklog = false;
-  } else {
-    _fetchingBacklog = true;
-    requestBacklogIfNeeded();
-  }
-}
-
-void ChatScene::requestBacklogIfNeeded() {
-  const int REQUEST_COUNT = 50;
-
-  if(!isBacklogFetchingEnabled() || !isFetchingBacklog() || !model()->rowCount()) return;
-
-  MsgId msgId = model()->data(model()->index(0, 0), ChatLineModel::MsgIdRole).value<MsgId>();
-  if(!_lastBacklogOffset.isValid() || (msgId < _lastBacklogOffset && _lastBacklogSize + REQUEST_COUNT <= model()->rowCount())) {
-    Client::backlogManager()->requestBacklog(bufferForBacklogFetching(), REQUEST_COUNT, msgId.toInt());
-    _lastBacklogOffset = msgId;
-    _lastBacklogSize = model()->rowCount();
+void ChatScene::requestBacklog() {
+  static const int REQUEST_COUNT = 50;
+  int backlogSize = model()->rowCount();
+  if(isSingleBufferScene() && backlogSize != 0 && _lastBacklogSize + REQUEST_COUNT <= backlogSize) {
+    QModelIndex msgIdx = model()->index(0, 0);
+    MsgId msgId = model()->data(msgIdx, ChatLineModel::MsgIdRole).value<MsgId>();
+    BufferId bufferId = model()->data(msgIdx, ChatLineModel::BufferIdRole).value<BufferId>();
+    _lastBacklogSize = backlogSize;
+    Client::backlogManager()->requestBacklog(bufferId, REQUEST_COUNT, msgId.toInt());
   }
 }