#!/usr/bin/env python
#
# GBackground v0.1
# (c) 2008 Adam Shamblin, adam@iratepublik.com
#
#   Inspired by Davyd's script:
#   http://oracle.bridgewayconsulting.com.au/~davyd/misc/change-background-py.html
#
#   This program is free software; you can redistribute it and/or modify
#   it under the terms of the GNU General Public License as published by
#   the Free Software Foundation; either version 2, or (at your option)
#   any later version.
#
#   This program is distributed in the hope that it will be useful,
#   but WITHOUT ANY WARRANTY; without even the implied warranty of
#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#   GNU General Public License for more details.
#
#   You should have received a copy of the GNU General Public License
#   along with this program; if not, write to the Free Software Foundation,
#   Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.

import gconf
import os
import random 
import time
from xml.dom.minidom import parse

class GBackground:

    def __init__ (self):
        
        self.backgroundsDB = '.gnome2/backgrounds.xml'

        self.__initGConfClient()
        self.__initDOM()

        self.__files = []

    def __initGConfClient (self):
        self.__gclient = gconf.client_get_default()

    def __initDOM (self):

        db = os.path.join( os.environ['HOME'], self.backgroundsDB )

        fh = open(db)
        self.__dom = parse(fh)
        fh.close()

    def loadBackgrounds (self):

        for wallpaper in self.__dom.getElementsByTagName('wallpaper'):

            if wallpaper.getAttribute('deleted') == 'true':
                continue

            filename = wallpaper.getElementsByTagName('filename')[0].firstChild.nodeValue
            self.__files.append(filename)

    def setRandomBackground (self):

        rnd = random.randint(0, len(self.__files) - 1)
        self.setBackground( self.__files[rnd] )

    def getBackground (self):
        return self.__gclient.get_string('/desktop/gnome/background/picture_filename')

    def setBackground (self, background):
        self.__gclient.set_string ("/desktop/gnome/background/picture_filename", background)


def main ():

    gb = GBackground()
    gb.loadBackgrounds()

    while (1):
        gb.setRandomBackground()
        time.sleep(900)


if __name__ == '__main__':
    main()