Script for forfeiting a Pokémon after losing a specific battle?

[jsawicki]

I'm trying to write a script where Team Rocket actually steals one of your pokemon when you lose a battle.
Has anyone done this / seen a script that works in this way that could be a base?

Fire Red Hack, using Hexmaniac Advance. I'm not much of a coder, but I'm learning a lot by doing this.

Thanks for any help!