A quick discussion board，no word limit

Can you help me understand this Law question?

On the way home from major dental surgery, Robert Nee stopped by his local car dealership. Because of the surgery, he was still groggy from the anesthesia. Mr. Nee’s dentist had also given him some powerful pain medication to minimize the pain in the mouth and jaw for the twenty-four hour period following the procedure.

While at the dealership, Mr. Nee negotiates with a salesperson for the purchase and sale of a well-equipped Jaguar. Mr. Nee mentions the surgery to the salesperson, but the salesperson does not notice anything out of the ordinary about this customer. The Jaguar Mr. Nee ultimately decided upon is a top of the line vehicle and the cost is $97,000.00. Mr. Nee puts a $30,000.00 down payment on the car by personal check and finances the rest. The transaction is reflected in appropriate contract documents and invoices and complies with all federal, state, and local regulations regarding the sale of a vehicle. All documentation is signed by both parties. The next day, Mr. Nee receives a phone call from the dealership stating his new car is ready for pick up. Mr. Nee does not really remember purchasing the car, although he has always wanted a Jaguar and dreamed about buying one the night before. Is this contract valid, enforceable, void or voidable? Fully explain your answer.