import logging
import os
import subprocess
import time
from collections.abc import Callable, Generator
from contextlib import contextmanager
from io import BytesIO
from threading import Thread

import psutil
import requests


def wait_for_worker_health(healthcheck_port: int) -> bool:
    worker_healthcheck_attempts = 0
    max_healthcheck_attempts = 25

    while True:
        if worker_healthcheck_attempts > max_healthcheck_attempts:
            raise Exception(
                f"Worker failed to start within {max_healthcheck_attempts} seconds"
            )

        try:
            requests.get(f"http://localhost:{healthcheck_port}/health", timeout=5)

            return True
        except Exception:
            time.sleep(1)

        worker_healthcheck_attempts += 1


def log_output(pipe: BytesIO, log_func: Callable[[str], None]) -> None:
    for line in iter(pipe.readline, b""):
        print(line.decode().strip())


@contextmanager
def hatchet_worker(
    command: list[str],
    healthcheck_port: int = 8001,
) -> Generator[subprocess.Popen[bytes], None, None]:
    logging.info(f"Starting background worker: {' '.join(command)}")

    os.environ["HATCHET_CLIENT_WORKER_HEALTHCHECK_PORT"] = str(healthcheck_port)
    env = os.environ.copy()

    proc = subprocess.Popen(
        command, stdout=subprocess.PIPE, stderr=subprocess.PIPE, env=env
    )

    # Check if the process is still running
    if proc.poll() is not None:
        raise Exception(f"Worker failed to start with return code {proc.returncode}")

    Thread(target=log_output, args=(proc.stdout, logging.info), daemon=True).start()
    Thread(target=log_output, args=(proc.stderr, logging.error), daemon=True).start()

    wait_for_worker_health(healthcheck_port=healthcheck_port)

    yield proc

    logging.info("Cleaning up background worker")

    parent = psutil.Process(proc.pid)
    children = parent.children(recursive=True)

    for child in children:
        try:
            child.terminate()
        except psutil.NoSuchProcess:
            pass

    try:
        parent.terminate()
    except psutil.NoSuchProcess:
        pass

    _, alive = psutil.wait_procs([parent] + children, timeout=5)

    for p in alive:
        logging.warning(f"Force killing process {p.pid}")
        try:
            p.kill()
        except psutil.NoSuchProcess:
            pass