#! /usr/bin/env python

import os
import sys
from subprocess import Popen, PIPE, call
import time
import signal


def find_open_terminals():
    """Search for open terminals with pattern /bin/login."""
    open_terminals = []
    process = Popen(["ps", "aux"], stdout=PIPE, stderr=PIPE)
    process.wait()
    process1 = Popen(["grep", "/bin/login"], stdin=process.stdout,
        stdout=PIPE, stderr=PIPE)
    process1.wait()
    stdout, stderr = process1.communicate()
    if len(stderr) > 0:
        return []
    tmp = stdout.decode("utf-8")
    for i in tmp.split("\n"):
        pid = " ".join(i.split()).split()
        if len(pid) == 0:
            continue
        open_terminals.append(int(pid[1]))
    return open_terminals

def lock_terminals(open_terminals):
    for pid in open_terminals:
        try:
            os.kill(pid, signal.SIGQUIT)
        except OSError as error:
            call(["logger", error])

def get_users():
    """Search for users with a display."""
    users = {}
    process = Popen(["pinky", "-fw"], stdout=PIPE, stderr=PIPE)
    process.wait()
    stdout, error = process.communicate()
    if len(error) != 0:
        call(["logger", "Could not found user logged in on X"])
        return
    tmp = stdout.decode("utf-8").split("\n")
    for i in range(len(tmp)):
        if len(tmp[i]) == 0:
            continue
        tmp_users = " ".join(tmp[i].split()).split()
        if tmp_users[1].startswith("?"):
            users[i] = {
                "name": tmp_users[0],
                "display": tmp_users[1].replace("?", "")
            }           
    return users

def lock_screens(x_users):
    for user in x_users.values():
        call(["logger", "Lock X screen for: %s" % user["name"]])
        cmd = "export DISPLAY=%s; " % user["display"]
        if user["name"] == "root":
            cmd += 'mate-screensaver-command -l'
        else:
            cmd += 'su %s -c "mate-screensaver-command -l"' % (user["name"])
        call(cmd, shell=True)
        time.sleep(1)


def main():
    lock_screens(get_users())
    lock_terminals(find_open_terminals())
    call("pm-suspend")


if __name__ == '__main__':
    main()