I've been asked to develop a system wherein employees can mark on a form their availability on a given day of the week - for instance an employee could mark themselves as available on a given time on a given week, and unavailable on some other time. It looks a little like this:

Currently this works by rendering checkboxes within the table, picking up click events in each cell and marking the checkbox and hence the cell appropriately. I'm using the JQuery "click n drag checkbox" plugin from here. However, I've been informed that there could well be more than two states for a given cell (for instance available, unavailable, available in a given circumstance), in which case binding to a checkboxes checked value isnt going to be a lot of help.

I've never used javascript or asp.net before and am unsure as to the best way to approach this problem. Ideally I could stick a data structure behind each cell which I could update to a certain state and then get my cell colour by binding to this - however I'm at something as a loss as how to best achieve this.