Request - Availability Scheduler

Looking for an add-on that could handle simple employee scheduling that can take advantage of EE’s flexibility with user management. Employees could log in and set their availability on a weekly basis, then add manual vacation dates. Employers/admins could then schedule an event and clearly see (through color coding…etc) who is available for selected times. Handles iCal schedules for individuals as well as a global schedule. Can have multiple global schedules (if that’s not a contradiction…)

I use a system like this at my job to schedule student employees to either concert recordings, crew or ushers. It is a stand-alone PHP app, but is in need of updating and we are debating on a commercial solution or having the student who wrote it to perform an update. I’m curious if there is a need for this out in the EE land.