#!/usr/bin/env python
"""
dogtail-detect session

This script checks for some main pieces of a running GNOME session, 
specifically gnome-panel and metacity. 

It checks to see that the gnome-panel node has at least some child nodes.
For example, the main gnome-panel node by default has two direct descendents:
the top panel, and the bottom panel.
Metacity's existence is also checked. However, metacity currently never has
any child nodes.

If a proper session is running, the scripts exits with a status of 0.
If no session is found, a non-zero exit code is returned.

Author: Zack Cerza <zcerza@redhat.com>
"""

__author__ = "Zack Cerza <zcerza@redhat.com>"

from dogtail.procedural import *
import sys


def GNOME():
    """
    "Is an accessibility-enabled GNOME session running?"
    """
    running = False
    try:
        assert focus.desktop
        assert focus.desktop.children

        focus.application('gnome-panel')
        assert focus.application.children

        focus.application('metacity')
        print focus.application.node
        assert focus.application.node
        running = True
        print "GNOME Session detected."
    except AttributeError or AssertionError or FocusError:
        print "ERROR: No session found."
    return running


def KDE():
    """
    "Is an accessibility-enabled KDE session running?"
    """
    running = False
    return running


def JustSomeApps():
    """
    "Is at least one accessibility-enabled application running?"
    """
    assert focus.desktop
    assert focus.desktop.children

if GNOME() or KDE() or JustSomeApps():
    sys.exit()
else:
    sys.exit(1)