import threading
import time
from datetime import datetime


class Clock:
    def __init__(self, value: int, increment: int) -> None:
        self.millis = value * 1000
        self.increment = increment * 1000

        self._run_event = threading.Event()
        self._terminate_event = threading.Event()
        self._lock = threading.Lock()

        self.thread = threading.Thread(target=self._update_clock, daemon=True)

    # ---------- time computation ----------

    def _compute_seconds(self) -> int:
        return (self.millis // 1000) % 60

    def _compute_minutes(self) -> int:
        return self.millis // 60000

    def _add_increment(self) -> None:
        self.millis += self.increment

    # ---------- thread logic ----------

    def _update_clock(self):
        while not self._terminate_event.is_set():
            self._run_event.wait()

            with self._lock:
                if self.millis <= 0:
                    self.millis = 0
                    self._run_event.clear()
                    break

                self.millis -= 1

            time.sleep(0.001)
    # ---------- public API ----------
    def is_running(self) -> bool:
        return self._run_event.is_set()

    def start(self) -> None:
        self._run_event.set()
        if not self.thread.is_alive():
            self.thread = threading.Thread(target=self._update_clock, daemon=True)
            self.thread.start()

    def stop(self) -> None:
        if self._run_event.is_set():
            with self._lock:
                self._add_increment()
            self._run_event.clear()

    def terminate(self) -> None:
        self._terminate_event.set()
        self._run_event.set()
        self.thread.join()

    def clock_to_str(self) -> str:
        with self._lock:
            minutes = self._compute_minutes()
            seconds = self._compute_seconds()
        return f"{minutes:02d}:{seconds:02d}"


if __name__ == "__main__":
    clock = Clock(600, 0)
    clock.start()
    while True:
        time.sleep(1)
        print(clock.clock_to_str())