"""Отложенный старт фоновых задач после create_app — разгрузка SD при boot."""

from __future__ import annotations

import logging
import platform
import threading
import time
from typing import Callable, Optional

_log = logging.getLogger(__name__)


def _is_arm() -> bool:
    machine = platform.machine().lower()
    return any(part in machine for part in ("arm", "aarch64"))


def default_startup_delay_sec(env_name: str, *, arm_default: float, other_default: float) -> float:
    import os

    raw = os.getenv(env_name, "").strip()
    if raw:
        try:
            return max(0.0, float(raw))
        except ValueError:
            pass
    return arm_default if _is_arm() else other_default


def schedule_deferred(
    fn: Callable[[], None],
    *,
    delay_sec: float,
    thread_name: str,
    log_label: str = "",
) -> None:
    sec = max(0.0, float(delay_sec))
    label = log_label or thread_name

    def _run() -> None:
        if sec > 0:
            _log.info("Отложенный старт через %.1f с: %s", sec, label)
            time.sleep(sec)
        try:
            fn()
        except Exception:
            _log.exception("Отложенный старт: сбой (%s)", label)

    threading.Thread(target=_run, daemon=True, name=thread_name).start()


def schedule_mdns_after_boot(app, *, delay_sec: Optional[float] = None) -> None:
    if delay_sec is None:
        delay_sec = default_startup_delay_sec(
            "WESP_STARTUP_MDNS_DELAY_SEC", arm_default=10.0, other_default=2.0
        )

    def _start() -> None:
        from app.services.mdns_service import ensure_mdns_running, schedule_mdns_retry_if_needed

        if not ensure_mdns_running(app, source="boot"):
            schedule_mdns_retry_if_needed(app)

    schedule_deferred(_start, delay_sec=delay_sec, thread_name="wesp-mdns-defer", log_label="mDNS")


def schedule_sync_requeue_after_boot(app, *, delay_sec: Optional[float] = None) -> None:
    if delay_sec is None:
        delay_sec = default_startup_delay_sec(
            "WESP_STARTUP_REQUEUE_DELAY_SEC", arm_default=45.0, other_default=15.0
        )

    def _start() -> None:
        from app import _start_sync_requeue_worker

        _start_sync_requeue_worker(app)

    schedule_deferred(
        _start, delay_sec=delay_sec, thread_name="wesp-requeue-defer", log_label="sync requeue"
    )


def schedule_bootstrap_update_env(app, *, delay_sec: Optional[float] = None) -> None:
    if delay_sec is None:
        delay_sec = default_startup_delay_sec(
            "WESP_STARTUP_BOOTSTRAP_DELAY_SEC", arm_default=2.0, other_default=0.0
        )

    def _run() -> None:
        with app.app_context():
            from app.services.auto_update_settings_service import bootstrap_update_environment

            bootstrap_update_environment(app)

    schedule_deferred(
        _run, delay_sec=delay_sec, thread_name="wesp-bootstrap-defer", log_label="OTA bootstrap"
    )