There are options of tent camping, chalets, a lodge, and hostel dorm rooms bookable through the park headquarters (do it in advance!). Staying in the park accommodations will give you the option to hike around and get in some very early morning wildlife viewing.
It will also give you the chance to do the evening nature walks led by a park guide (weather permitting).
Beware, especially if tent camping, of the monkeys. They can and will get into your tent, and even cabins to rifle through food and belongings. Monkeys have no manners, especially Macaques.