employee schedule

okay, I am a restaurant manager. I am looking for a way to simplify my employee schedule by putting in each employees availability and which positions they can work. Then I need it to automatically schedule 1 person for each position that I need. so... say for example I need 3 cooks - 2 bussers - 1 host - and 8 servers - I want it to automatically schedule the desired number of people who can work and only the people that can work the needed positions. Also, I want it to have an easy way for employees to request off certain days. Anyone able to help me figure this entire maze out? Ive started it several times but then I just get lost in this weird formula maze