Unfortunately dc voltage can be very harmful when the polarity is reversed. I would try to disconnect the battery for a few minutes to see if it will reset. Your computer may have suffered a short from the power being reversed. The next question would be does the alternator appear to be charging because it is also controlled by the computer witch could explain why it was being jumped off to begin with. it is not uncommon for the computers
section responsible for controlling the alternator to burn out .