calendar project

I'm looking for a script that can perform the following functions: I need to have a script that will have a MAIN calendar, where I put in the events.... but individual users on my site will get their own calendars, too. I'm going to have a lot of events on this site... so I need to have a main calendar with events, and members need to be able to fill in their details for certain events as registration is limited and this needs to be hands off. They should NOT be able to change existing details that I've already created, though. The events need to then be automatically bolded on their personal calendars, and they should get an email notification when the event is near. Calendars need a monthly, weekly, and detailed daily view mode.