As nobody else has answered: I am not aware of any such implementation.
It might be doable, but might require some effort. For the layout, you could consider using a HorizontalLayout which contains VerticalLayouts, or some other suitable arrangement. Also a GridLayout could be enough depending on the layout options you want, or you might want to go for ultimate flexibility (at the cost of complexity and possible component overlaps etc.) with AbsoluteLayout.
So: create your “portlet panel” class with the mode selection and some kind of view management, instantiate or inherit it for actual “portlets” and create a top-level component that takes care of the layout of such “portlet panels”. I believe others would be interested if you develop such an add-on and can publish it in
the Directory
.
For drag and drop support (this is the tricky bit), the
DragDropLayouts add-on
might make it possible to support dragging such “portlet panels” to a layout “slot”. The
Visual Editor
does something like this using the add-on, but with several additional layers of complexity.