I think this is a combination of misunderstanding. I assume this dog is allowed to run "free" since sounds like a country setting. Your timing may have been "off" to come by for the visit. Next time wait for the dog to be further away from the house to make contact. Your more likely on less sacried ground there.
Where you walking straight toward the dog? NEVER walk toward a dog and into it's eyes at the same time!!!!!!! This is an aggressive move by you. They will bite and attack. Always walk backwards slowly and no eye contact when getting near an aggressive dog.
Always let the dog sniff you or your hand prior to petting. Let the dog know who you are. Next time your with your friend have the dog smell you in their presence. The dog will understand you are a friend to the owner.
You have every right to let your friend know about the bite. However, you most likely would not win a lawsuit since you were technically "trespassing" and not viewed as a welcome guest at the time of the visit.
You and this dog need to make friends. Slow things down a bit and learn each others behaviors. That way you can both pass eachother without harm.