#!/usr/bin/env python3


# Copyright (c) 2012, Matthias Schiffer <mschiffer@universe-factory.net>
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
#
#   1. Redistributions of source code must retain the above copyright notice,
#      this list of conditions and the following disclaimer.
#   2. Redistributions in binary form must reproduce the above copyright notice,
#      this list of conditions and the following disclaimer in the documentation
#      and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.


import signal
import sys
import os
import pwd
import locale
import argparse

from gi.repository import Gtk, Gdk, Gio

from Locker import Locker
from LockWindow import LockWindow
import Message
import pam


_ = locale.gettext


def get_username():
    return pwd.getpwuid(os.getuid())[0]


theme = 'UzL-login'


parser = argparse.ArgumentParser(prog='pylock', description=_('GTK-based screen locker.'))
parser.add_argument('-t', '--timeout', type=int, default=0, help=_('Start in daemon mode that will automatically activate after a given time of inactivity.'))
parser.add_argument('-l', '--logout', type=int, default=0, help=_('Allow to logout the current user after a given time.'))
parser.add_argument('-c', '--logout-command', help=_('Specifies the command to be called to log out a user.'))
parser.add_argument('-u', '--username', default=get_username(), help=_('Set the name of the user that is able to unlock the screen.'))

args = parser.parse_args()


def handler(signum, frame):
    Gtk.main_quit()


signal.signal(signal.SIGINT, handler)
signal.signal(signal.SIGTERM, handler)
signal.signal(signal.SIGQUIT, handler)


locale.setlocale(locale.LC_ALL, '')
locale.textdomain('pylock')

Gtk.Settings.get_default().set_property('gtk-theme-name', theme)


if Message.getSelection() != 0:
    if args.timeout == 0:
        Message.sendLockMessage()
        exit(0)
    else:
        print('There seems to be a Pylock instance already running.', file=sys.stderr)
        exit(1)


window = LockWindow()

if not Message.acquireSelection(window):
    print('Unable to register for lock messages', file=sys.stderr)


def lock(timeLeft):
    window.updateLockMessage(args.username, timeLeft)
    return window.lock()

def logout():
    try:
        os.system(args.logout_command)
    except:
        pass

    window.reset(False)

def updateTimeout(timeLeft):
    window.updateLockMessage(args.username, timeLeft)

if args.logout_command is None:
    locker = Locker(args.timeout, lock, window.unlock)
else:
    locker = Locker(args.timeout, lock, window.unlock, args.logout, logout, updateTimeout)


def _triggerLock(w, e):
    locker.lock()

window.connect('map-event', _triggerLock)


pamAuth = pam.pam()

def tryUnlock(w, password):
    if pamAuth.authenticate(args.username, password):
        locker.unlock()

        if args.timeout == 0:
            Gtk.main_quit()
    else:
        window.reset()
        window.setAuthMessage(pamAuth.reason)

    return True

window.connect('logout', lambda w: locker.logout())
window.connect('tryUnlock', tryUnlock)

Gtk.main()