import os
import sys
import socket
import time
import subprocess

CHECK_USERS_CMD = ["/root/mcrcon/mcrcon", "-H", "192.168.0.21", "-p", "password", "list"]
CHECK_INTERVAL = 60
WASTED_LIMIT = 20 * 60

def are_users_there():
    try:
        output = subprocess.check_output(CHECK_USERS_CMD)
    # Maybe, server isn't running?
    except subprocess.CalledProcessError as err:
        print(f"Cannot access mcrcon: {err}", flush=True)
        return True
    header = output.decode().split("\n")[0]
    if header.startswith("There are 0 of"):
        return False
    return True

def server_shutdown():
    subprocess.run("service minecraft stop".split(" "))

def server_startup():
    subprocess.run("service minecraft start".split(" "))

def main():
    wasted_cnt_seconds = 0
    while True:
        if are_users_there():
            wasted_cnt_seconds = 0
            print("Users ok", flush=True)
            time.sleep(CHECK_INTERVAL)
            continue

        wasted_cnt_seconds += CHECK_INTERVAL
        print(f"No users ({wasted_cnt_seconds})", flush=True)
        if wasted_cnt_seconds > WASTED_LIMIT:
            print("Wasted limit", flush=True)
            server_shutdown()
            wait_client()
            server_startup()
            print("Server started", flush=True)
            wasted_cnt_seconds = 0

        time.sleep(CHECK_INTERVAL)

def wait_client():
    sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    sock.bind(("0.0.0.0", 25565))
    print("Listening...", flush=True)
    sock.listen(0)
    connection, address = sock.accept()
    print(f"Connection from: {address}", flush=True)
    connection.close()
    sock.close()

if __name__ == '__main__':
    main()