Multiuser web-based calendar based on php, mysql, javascript

I'm searching for a multiuser web-based calendar system that supports multiple users. I'm looking for these features:

• Multiple users
• Two user groups: First gro开发者_开发百科up is allowed to see events, the second group can create and edit events
• The events should be stored in a mysql database or a file
• The system has to be (very) easy to use. It will be used by non-technical users
• Ideally it should be integrated in wordpress, but thats a nice-to-have

If you know something like this please let me know.

edit (concerning the google apps comment): the calendar should be hosted on an existing website

I totally understand your issue with your client. I had the same issue explaining to my boss that Google docs were more secure then a shared excel spread sheet. This is what finally convinced her, I pointed her to the attacks against Google from China. --source http://www.wired.com/threatlevel/2010/01/operation-aurora/

I then explained that it would take billions of dollars in R&D to even come close to the level of security that Google provides.

If that doesn't work I would suggest using one of the many many OS calendars out there (http://arshaw.com/fullcalendar/ looks awesome) and go from there.

Google Calendar as you can embed it onto any site

http://www.google.com/support/calendar/bin/answer.py?hl=en&answer=41207

Wordpress plugin

http://wordpress.org/extend/plugins/google-calendar-plugin/

I did find another option

• http://arshaw.com/fullcalendar/

Please excuse the plug but it honestly matches the Q almost completely:

http://ican.openacalendar.org/

• Multiple users

Yes!

• Two user groups: First group is allowed to see events, the second group can create and edit events

Anyone can see the calendar including anonymous users. It can be configured so only certain users can write to calendar.

• The events should be stored in a mysql database or a file

Postgresql DB - MySQL wouldn't be hard for a programmer to do. Lots of export options (iCal, JSON, News feed) so you can do what you want with them.

• The system has to be (very) easy to use. It will be used by non-technical users

Everything is editable throught a web UI which has been battle-tested and received good feedback explicitly on being easy to use.

• Ideally it should be integrated in wordpress, but thats a nice-to-have

Not sure what you mean by integrated, but we have a Wordpress plugin that will display events on your blog.

The improvement we offer over Google Calendar is that many users can work on the same calendar and all edits are logged for safety - so you don't have to worry about one user's mistake trashing all the data, which sadly can happen with Google Calendar.

I have used http://www.k5n.us/webcalendar.php in the past. It hasn't been updated recently, but it does still work. It doesn't have wordpress integration out of the box, but does have the ability to be integrated with other CMS.