I am looking for advice or examples of how to create a timetable widget as shown in the image below;

I need the user to be able to drag the rectangles to move or resize them up and down each column of the timetable.
It’s quite simple when you look at it but I imagine the JavaScript involved is quite tricky and I just don’t know where to start.
I’m thinking of using a table and overlaying div’s but that’s about as far as I’ve got.
Instead of reinventing the wheel, how about using the jQuery Fullcalendar plugin? Just use the week view.