#!/usr/bin/python3

import atexit
import fcntl
import io
import os
import signal
import selectors
import subprocess
import sys
import sisyphus.checkenv
import sisyphus.getclr
import sisyphus.killemerge
import sisyphus.syncdb


def set_nonblocking(fd):
    flags = fcntl.fcntl(fd, fcntl.F_GETFL)
    fcntl.fcntl(fd, fcntl.F_SETFL, flags | os.O_NONBLOCK)


def spinner_animation():
    spinner = ['-', '\\', '|', '/']
    sel = selectors.DefaultSelector()
    sel.register(sys.stdin, selectors.EVENT_READ)

    for _ in range(10):
        for char in spinner:
            sys.stdout.write('\b' + char)
            sys.stdout.flush()
            events = sel.select(timeout=0.1)
            if events:
                return
    sys.stdout.write('\b')


def sigint_handler(signal, frame):
    sys.exit(0)


signal.signal(signal.SIGINT, sigint_handler)


def start(gfx_ui=False):
    args = ['--quiet', '--depclean']

    if sisyphus.checkenv.root() and not gfx_ui:
        print("\n" + sisyphus.getclr.bright_white + "Orphaned, no longer needed packages are slated for" + sisyphus.getclr.reset + " " +
              sisyphus.getclr.green + "'safe'" + sisyphus.getclr.reset + " " + sisyphus.getclr.bright_white + "removal." + sisyphus.getclr.reset + "\n")
        while True:
            user_input = input(sisyphus.getclr.bright_white + "Would you like to proceed?" + sisyphus.getclr.reset + " " +
                               "[" + sisyphus.getclr.bright_green + "Yes" + sisyphus.getclr.reset + "/" + sisyphus.getclr.bright_red + "No" + sisyphus.getclr.reset + "]" + " ")
            if user_input.lower() in ['yes', 'y', '']:
                p_exe = subprocess.Popen(['emerge'] + args)
                try:
                    set_nonblocking(sys.stdout.fileno())
                    spinner_animation()

                    sel = selectors.DefaultSelector()
                    sel.register(sys.stdin, selectors.EVENT_READ)

                    while True:
                        events = sel.select(timeout=0.1)
                        for key, mask in events:
                            if key.fileobj == sys.stdin:
                                line = sys.stdin.readline().strip()
                                if line.lower() == 'q':
                                    sys.exit()
                        if p_exe.poll() is not None:
                            break
                except KeyboardInterrupt:
                    p_exe.terminate()
                    try:
                        p_exe.wait(1)
                    except subprocess.TimeoutExpired:
                        p_exe.kill()
                    sys.exit()
                finally:
                    p_exe.wait()
                sisyphus.syncdb.lcl_tbl()
                break
            elif user_input.lower() in ['no', 'n']:
                break
            else:
                print("\nSorry, response" + " " + "'" +
                      user_input + "'" + " " + "not understood.\n")
                continue
    elif gfx_ui:
        p_exe = subprocess.Popen(
            ['emerge'] + args, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
        # kill portage if the program dies or it's terminated by the user
        atexit.register(sisyphus.killemerge.start, p_exe)

        for p_out in io.TextIOWrapper(p_exe.stdout, encoding="utf-8"):
            print(p_out.rstrip())

        p_exe.wait()
        sisyphus.syncdb.lcl_tbl()
    else:
        print(sisyphus.getclr.bright_red +
              "\nYou need root permissions to do this!\n" + sisyphus.getclr.reset)
        sys.exit()