# -*- python -*-
'''
xpybar – xmobar replacement written in python
Copyright © 2014, 2015, 2016, 2017, 2018  Mattias Andrée (maandree@kth.se)

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 3 of the License, 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, see <http://www.gnu.org/licenses/>.
'''

import os

import Xlib.Xatom

from x import *


class XDisplay:
    '''
    Retrieve information about the used X display as specified by the DISPLAY environment variable
    
    @variable  connection:str?  The full X display information, `None` if X is not running
    @variable  host:str?        The host, often `None` one local conncetions and "localhost" on remote oonnection
    @variable  display:int?     The display number
    @variable  screen:int?      The screen number, often `None` (default screen)
    @varaible  vt:int           The VT the X display is allocated to
    
    host, dispay and screen is None if connection is None, which means that when
    you started, xpybar's DISPLAY environment variable is not set, and that a
    display was configured in the settings.
    '''
    
    
    def __init__(self):
        '''
        Constructor
        '''
        self.connection = os.environ['DISPLAY'] if 'DISPLAY' in os.environ else None
        if self.connection is None:
            self.host = None
            self.display = None
            self.screen = None
        else:
            self.host = ':'.join(self.connection.split(':')[:-1])
            if self.host.startswith('[') and self.host.endswith(']'):
                self.host = self.host[1 : -1]
            if self.host == '':
                self.host = None
            self.display, self.screen = (self.connection.split(':')[-1] + '.').split('.')[:2]
            self.display = int(self.display)
            self.screen = None if self.screen == '' else int(self.screen)
        r = get_screen().root
        d = get_display()
        self.vt = r.get_full_property(d.get_atom('XFree86_VT'), Xlib.Xatom.INTEGER).value.decode('utf-8', 'replace')[0]