tailight for motorcycle

I have a LED tail light on my bike with two rows of bulbs (approx 10 bulbs on each row). I want to segment it in such way so that i can use the bulbs on the ends of the tail light as my turn signals. In a perfect world, i'd like for all bulbs to light up red when i press the brakes, and if i am pressing the brake plus using the turn signals, then the selected end bulbs would start flashing while the remainder of the bulbs remain lit. This is what the light looks like.

Sorry, forgot to ask my question. How would I go about doing this??...relays??

Anyone??