private void addNodeToTree(
JTree.DropLocation dropLocation,
LayerTreeModel model,
INode node,
boolean alreadyInTree,
int offset) {
TreePath p = dropLocation.getPath();
boolean noparent = p == null;
INode parent = null;
int index = 0;
if (!noparent) {
parent = (INode) p.getLastPathComponent();
index = dropLocation.getChildIndex();
if (index < 0) index = parent.getChildCount();
else index += offset;
}
if (alreadyInTree) {
if (!noparent) {
if (node == parent || nodeAncestorOf(node, parent)) return;
if (node.getParent() == parent && index > model.getIndexOfChild(parent, node)) index--;
}
model.removeNodeFromParent(node, false);
}
if (noparent) model.addToRoot(node, true);
else model.insertNodeInto(node, parent, index, true);
}