Which PHP calendar will suit my needs? Or build my own?

There are so many web based calendars out there that I'm not sure which will best suit my purposes.

I want to create an events calendar, which I suppose looks and functions in much the same way as google calendar. But users shouldn't need to s开发者_JS百科ign up for a gmail account or a google account. Users of my social network website should be able to create events in the calendar and share it with other friends in their "friend network". In month, year or day views, you can mouse hover events to see a bubble dialog that lists events in detail. People need to pay a monthly fee to use my website (not sure if this prevents me from using google apps).

So is something like Google Calendar the way to go? Or are there other php/javascript calendars out there that already meet my needs? Or will it just save me more time to build my own?

Check out full calendar by arshaw.

This is a jQuery plugin that provides a full-sized, drag & drop calendar just like google calendar. one can also customize it easily.

Full Calenadar Link.

if you are going your own route then best to build on something already there and open. iCal is an open and available calendar spec and there are php implementations, but they would be extensible and you would following a standard.