# Инициализация Celery-приложения и периодических задач.

import logging

from celery import Celery
from celery.signals import worker_process_init, worker_ready, setup_logging as celery_setup_logging
from redis import Redis

from ..core.config import settings
from ..core.logs import setup_logging

logger = logging.getLogger("iaai_scraper.worker.celery_app")
STARTUP_SYNC_DISPATCH_KEY = "iaai:state:startup_sync_dispatched"


@celery_setup_logging.connect
def _configure_logging(loglevel=None, **kwargs):
    # Перехватываем логирование Celery и пишем только в stderr (Docker logs).
    level = settings.log_level if settings.log_level else "INFO"
    setup_logging(level, None)


@worker_process_init.connect
def _on_worker_process_init(**kwargs):
    # Повторно настраиваем логирование в каждом дочернем prefork-процессе,
    # чтобы StreamHandler(stderr) корректно работал после fork.
    level = settings.log_level if settings.log_level else "INFO"
    setup_logging(level, None)

    # Сбрасываем cached engine/redis после fork — иначе child наследует
    # коннекты родителя, что небезопасно (особенно с psycopg2).
    from . import tasks as _tasks
    _tasks._CACHED_PERSISTENCE = None
    _tasks._CACHED_REDIS = None


def _broker_url() -> str:
    return settings.celery.broker_url or settings.redis.url


def _result_backend() -> str:
    return settings.celery.result_backend or settings.redis.url


celery_app = Celery(
    "iaai_scraper",
    broker=_broker_url(),
    backend=_result_backend(),
)

# Auto-clamp: если hard limit слишком далёк от soft (> soft + 120),
# ограничиваем, чтобы зависший worker не жил вечно.
_soft = settings.celery.task_soft_time_limit
_hard = settings.celery.task_time_limit
_max_hard = _soft + 120 if _soft else _hard
if _hard > _max_hard:
    logger.warning(
        "CELERY_TASK_TIME_LIMIT=%d too far from CELERY_TASK_SOFT_TIME_LIMIT=%d; "
        "clamping hard limit to %d",
        _hard, _soft, _max_hard,
    )
    _hard = _max_hard

celery_app.conf.update(
    task_serializer="json",
    accept_content=["json"],
    result_serializer="json",
    timezone="UTC",
    enable_utc=True,
    task_soft_time_limit=_soft,
    task_time_limit=_hard,
    task_acks_late=True,
    task_reject_on_worker_lost=True,
    task_track_started=True,
    task_ignore_result=True,
    worker_concurrency=settings.celery.worker_concurrency,
    worker_max_tasks_per_child=settings.celery.worker_max_tasks_per_child,
    worker_max_memory_per_child=settings.celery.worker_max_memory_per_child_kb,
    worker_pool="prefork",
    worker_prefetch_multiplier=1,
    broker_connection_retry_on_startup=True,
    broker_transport_options={
        "visibility_timeout": settings.celery.broker_visibility_timeout,
    },
    result_expires=3600,
    worker_redirect_stdouts=False,
    worker_hijack_root_logger=False,
    beat_schedule={
        "periodic-sync-listing": {
            "task": "iaai_scraper.worker.tasks.sync_listing_task",
            "schedule": settings.celery.beat_sync_interval_minutes * 60.0,
            "args": (),
            "kwargs": {"limit": settings.celery.beat_sync_limit, "only_new": False},
            "options": {"queue": "scraping"},
        }
    },
    task_routes={
        "iaai_scraper.worker.tasks.*": {"queue": "scraping"}
    },
)

celery_app.autodiscover_tasks(["iaai_scraper.worker"])


@worker_ready.connect
def _on_worker_ready(**kwargs):
    """Сразу при старте worker отправляем первую задачу sync_listing,
    чтобы не ждать час до первого beat-цикла."""
    try:
        redis_client = Redis.from_url(
            settings.redis.url,
            decode_responses=True,
            socket_connect_timeout=settings.redis.socket_connect_timeout_seconds,
            socket_timeout=settings.redis.socket_timeout_seconds,
            health_check_interval=settings.redis.health_check_interval_seconds,
            retry_on_timeout=True,
        )
        # Дедуп TTL = интервал beat (по умолчанию 1ч), чтобы не плодить дубликаты
        # при flapping-рестартах контейнера.
        dedupe_ttl = max(600, settings.celery.beat_sync_interval_minutes * 60)
        should_dispatch = bool(redis_client.set(STARTUP_SYNC_DISPATCH_KEY, "1", nx=True, ex=dedupe_ttl))
    except Exception:
        logger.warning("Worker ready startup sync dedupe check failed; skipping immediate dispatch", exc_info=True)
        return

    if not should_dispatch:
        logger.info("Worker ready immediate sync already dispatched recently; skipping duplicate enqueue")
        return

    logger.info("Worker ready — dispatching initial sync_listing task")
    celery_app.send_task(
        "iaai_scraper.worker.tasks.sync_listing_task",
        kwargs={"limit": settings.celery.beat_sync_limit, "only_new": False},
        queue="scraping",
    )