I have wanted to build a "good" automated lighting controller and finally have constructed one that's almost confusing enough! No- really once it's set up you don't have to do anything to it other than let it control the lights and save the battery if you make a mistake. I've installed 3 of these, 2 in cars whose drivers are completely non-technical. They love the auto lights!

Automotive Lighting Control Module Instructions

The program code was written in PBP. The MCU used in this setup is a Microchip PIC16F628
(Other Microcontroller projects.)

These pictures are pretty poor. The flash on the camera made the interior look dirty but youget the idea.
The blue dot in the defroster is the cadmium sulfide cell. The LCM reads resistance of this to determine if lights are necessary.

With the headlights switch in this position the lights are ready to operate automatically when needed.

http://home.hiwaay.net/~davida1