"""
统一的外部请求超时控制工具

- install_default_requests_timeout: 给所有基于 requests 的外部请求
  （akshare、tushare、pywencai 等）注入默认超时，调用方未指定 timeout 时生效。
- call_with_timeout: 在独立线程中执行阻塞调用，超过时限立即放弃等待，
  防止个别环节长时间卡死整个程序。
"""

import os
import threading

# 默认连接超时 / 读取超时（单位：秒），可通过环境变量覆盖
DEFAULT_CONNECT_TIMEOUT = float(os.getenv("HTTP_CONNECT_TIMEOUT", "6"))
DEFAULT_READ_TIMEOUT = float(os.getenv("HTTP_READ_TIMEOUT", "20"))
DEFAULT_CALL_TIMEOUT = float(os.getenv("HTTP_CALL_TIMEOUT", "30"))

_installed = False
_install_lock = threading.Lock()


def install_default_requests_timeout(connect_timeout=None, read_timeout=None):
    """给 requests 库注入默认超时（仅当调用方未显式指定 timeout 时生效）。"""
    global _installed
    with _install_lock:
        if _installed:
            return

        connect = DEFAULT_CONNECT_TIMEOUT if connect_timeout is None else connect_timeout
        read = DEFAULT_READ_TIMEOUT if read_timeout is None else read_timeout

        try:
            import requests.sessions
            original_request = requests.sessions.Session.request

            def request_with_timeout(self, method, url, **kwargs):
                if kwargs.get("timeout") is None:
                    kwargs["timeout"] = (connect, read)
                return original_request(self, method, url, **kwargs)

            requests.sessions.Session.request = request_with_timeout
            _installed = True
            print(f"✅ 已为外部请求注入默认超时（连接 {connect}s / 读取 {read}s）")
        except Exception as e:
            print(f"⚠️ 注入 requests 默认超时失败: {e}")


def call_with_timeout(func, timeout=None, *args, **kwargs):
    """在线程中执行函数，超过 timeout 秒则放弃等待并抛出 TimeoutError。

    注意：超时后线程会继续在后台运行直至结束（守护线程），不会影响主程序。
    """
    if timeout is None:
        timeout = DEFAULT_CALL_TIMEOUT
    if timeout <= 0:
        return func(*args, **kwargs)

    result_box = {}

    def _run():
        try:
            result_box["ok"] = True
            result_box["value"] = func(*args, **kwargs)
        except BaseException as e:  # noqa: BLE001
            result_box["ok"] = False
            result_box["error"] = e

    worker = threading.Thread(target=_run, daemon=True)
    worker.start()
    worker.join(timeout)

    if worker.is_alive():
        func_name = getattr(func, "__name__", "function")
        raise TimeoutError(f"调用 {func_name} 超过 {timeout}s 未返回，已放弃等待")
    if result_box.get("ok"):
        return result_box["value"]
    raise result_box.get("error", RuntimeError("未知错误"))