Making classcolored bars -- how?

[Sojik]

I have begun work on a mod that does what kTargetHighlight does but for arena teammates and for arena enemies. If someone on either team targets someone on the opposite team the targeted unit will have a class colored bar of the person targeting them. If multiple people on the opposing team target the same unit the bar will fragment to show each enemy targeting that unit.

A picture will probably help illustrate what I'm trying to accomplish:

Image credit to Kryso. What we're looking at is an enemy druid targeting the priest and an enemy priest and mage targeting the paladin.

I have come up with some functions that can return when party#targets and arena#targets change but I'm at a block as to where to go from there. I'm new to this and I'm mostly learning as I go so I don't know how to handle feeding that information into other functions to draw the bar indicators or how to handle the fragmented bars.

I'm hoping for some help/advise/ideas. Thanks!

Oh here's the code I have so far if that helps (it all works in my tests so far):

http://www.pastey.net/136879

All the prints are for my testing. The final addon won't print a thing.