I wasn't invited to a baby shower but was asked for a large present?

My friend of almost 3 years asked me to buy a large present costing around $270 dollars. I was not invited to the baby shower. I don't know what to do I am pretty upset about not being invited. She said it kind of jokingly asking me and I made a joke back and asked where the registration was and price but I only assumed the details on the invitation. This friend and I are not close but see each other around others I have no plans of being in the childs life and dont know any other details about the baby. So I don't want her to expect that but I dont know what situation to give the present in. So I dont know what to do.