How to determine the user's activity status?

Question

System administration

Collective intelligence, tell me, please, what are the solutions or how to properly organize the tracking of the activity status of the windows system user?
By analogy with how the status change works when there is no activity to "out of office" in Skype or other im-clients. The ultimate task is to change the status in a corporate web application, so the solution must be able to send messages to the server when the status changes.

Answer 1

With such applications, you spoil the karma for yourself and the life of others, run away from there.
Get info when was the last event from user GetLastInputInfo
see
msdn.microsoft.com/en-us/library/ms646302%28VS.85%...

Answer 2

The first thing that comes to mind is to set a timer for n minutes, if there is an input interrupt (keyboard / mouse), then restart the timer, otherwise there is a signal of inactivity.

Answer 3

Lync.