What to reply when he says stuff like this?

This guys I really like (and who most likely likes me) always send me weird messages that I don't know how to reply to. A lot of times he sends "I love you" and "we're perfect for each other." I like him a lot but I don't want to say I love him or say I agree that we should date because I feel like it might all be a big joke. Usually I just make a joke or witty remark, but I want to let him know how I feel. What should I reply? Do you think he's just joking?