#!/usr/bin/env python3
# This file is placed in the Public Domain.


"main"


import getpass
import os
import pwd
import readline
import sys
import termios
import time


sys.path.insert(0, os.getcwd()) # pylint: disable=C0413


from op.client  import Client, cmnd, parse_cmd
from op.default import Default
from op.errors  import debug, enable, errors
from op.event   import Event
from op.object  import cdir
from op.run     import broker, dte, init, scan
from op.workdir import Workdir, skel


from op import mod


Cfg             = Default()
Cfg.dis         = ""
Cfg.mod         = "cmd,mod"
Cfg.opts        = ""
Cfg.name        = __file__.rsplit(os.sep, maxsplit=1)[-1]
Cfg.version     = "1"
Cfg.wdr         = os.path.expanduser(f"~/.{Cfg.name}")
Cfg.pidfile     = os.path.join(Cfg.wdr, f"{Cfg.name}.pid")


Workdir.workdir = Cfg.wdr


class Console(Client):

    "Console"

    def __init__(self):
        Client.__init__(self)
        broker.add(self)

    def announce(self, txt):
        "disable announce."

    def callback(self, evt):
        "wait for callback."
        Client.callback(self, evt)
        evt.wait()

    def poll(self):
        "poll console and create event."
        evt = Event()
        evt.orig = object.__repr__(self)
        evt.txt = input("> ")
        evt.type = "command"
        return evt

    def say(self, _channel, txt):
        "print to console"
        txt = txt.encode('utf-8', 'replace').decode()
        print(txt)


def daemon(pidfile, verbose=False):
    "switch to background."
    # pylint: disable=W0212
    pid = os.fork()
    if pid != 0:
        os._exit(0)
    os.setsid()
    pid2 = os.fork()
    if pid2 != 0:
        os._exit(0)
    if not verbose:
        with open('/dev/null', 'r', encoding="utf-8") as sis:
            os.dup2(sis.fileno(), sys.stdin.fileno())
        with open('/dev/null', 'a+', encoding="utf-8") as sos:
            os.dup2(sos.fileno(), sys.stdout.fileno())
        with open('/dev/null', 'a+', encoding="utf-8") as ses:
            os.dup2(ses.fileno(), sys.stderr.fileno())
    os.umask(0)
    os.chdir("/")
    if os.path.exists(pidfile):
        os.unlink(pidfile)
    cdir(os.path.dirname(pidfile))
    with open(pidfile, "w", encoding="utf-8") as fds:
        fds.write(str(os.getpid()))


def privileges(username):
    "drop privileges."
    pwnam = pwd.getpwnam(username)
    os.setgid(pwnam.pw_gid)
    os.setuid(pwnam.pw_uid)


def wrap(func):
    "restore console."
    old2 = None
    try:
        old2 = termios.tcgetattr(sys.stdin.fileno())
    except termios.error:
        pass
    try:
        func()
    except (KeyboardInterrupt, EOFError):
        print("")
    finally:
        if old2:
            termios.tcsetattr(sys.stdin.fileno(), termios.TCSADRAIN, old2)


def main():
    "main"
    enable(print)
    skel()
    parse_cmd(Cfg, " ".join(sys.argv[1:]))
    if Cfg.sets.dis:
        Cfg.dis += "," + Cfg.sets.dis
    if "a" in Cfg.opts:
        Cfg.mod = ",".join(mod.__dir__())
    scan(mod, Cfg.mod, Cfg.dis)
    if "v" in Cfg.opts:
        debug(f"{Cfg.name.upper()} {Cfg.opts.upper()} started {dte}")
        debug(f"scanned {Cfg.mod}")
    if "h" in Cfg.opts:
        print(__doc__)
    elif "d" in Cfg.opts:
        Cfg.mod  = ",".join(mod.__dir__())
        Cfg.user = getpass.getuser()
        daemon(Cfg.pidfile, "v" in Cfg.opts)
        privileges(Cfg.user)
        init(mod, Cfg.mod, Cfg.dis)
        while 1:
            time.sleep(1.0)
    elif "c" in Cfg.opts:
        init(mod, Cfg.mod, Cfg.dis)
        csl = Console()
        csl.start()
        while 1:
            time.sleep(1.0)
    elif Cfg.otxt:
        cmnd(Cfg.otxt, print)


if __name__ == "__main__":
    readline.redisplay()
    wrap(main)
    errors()
