notification enhancements

[Havoc Pennington <hp redhat com>]

Hi,

Trying to figure out a couple of problems at once.

First a longstanding issue, which is the Mugshot notification popups 
colliding with the ones from notification-daemon. As will be obvious to 
anyone who's looked at both, there is no way imaginable to use libnotify 
to get the Mugshot UI, but the two popups should coordinate so only one 
is visible at a time, and also they should probably share the logic for 
detecting a fullscreen app or detecting user idleness.

Second is a simpler thing, in wanting to do Google calendar or mail 
notifications, Bryan made me a design that's roughly similar to 
libnotify but has a few little details that aren't implementable with 
the current protocol version.

Third, Big Board and Mugshot are supposed to work on the last year's 
worth of Linux distribution releases or so, which makes it hard to 
modify notification-daemon, at least in the short term.


Given those issues, there are obviously long-term and short-term approaches.

In the long term, Owen suggested that notification-daemon export more of 
a "coordination" API, that would allow multiple apps that want to pop 
something up to say "I am showing something now" and block the other 
cooperating apps during that time.

A simple extension of that API would also provide calls or signals to 
detect idleness and fullscreen app / screensaver. Or perhaps it's 
simpler than that - maybe when an app is fullscreen or the user is idle, 
the daemon claims "I am showing something" and thus blocks all other 
notifications.

In the short term, here are some hacks I can come up with:
 - use Xlib hacks to try and determine when a notification
   window is on the screen
 - take over the notification service from notification-daemon and
   provide the same D-Bus API

Suggestions are welcome.

Havoc