If you are plan to use this special offered bus
( http://seasidekyoto.blogspot.jp/2014/01/special-bus-offer-in-march-2014-80off.html )
and want to visit Amanohashidate&Ine in a day, it won't work, I'm sure of that (Except you are going to do crazy rush asian way of sightseeing.).
I highly recommend you to stay overnight if you are intereted to visit both.