"""上传/转码链路（IngestJob + Asset）孤儿清理核心逻辑。

#1714：generation 链路有 cleanup_stale_running/pending 兜底，但上传链路
（ingest_jobs + assets）没有。worker 容器重启/进程 OOM 时，已 prefetch 的
celery 消息会丢失（transcode 队列 worker_prefetch_multiplier=1，消息预取后
宕机即丢失，Redis 队列里也不再存在），导致：

- ingest_jobs.status 永久卡 pending/processing
- assets.status 永久卡 processing/uploading（complete 阶段预建的占位）

本模块提供纯核心（session 注入，便于单测）：超时阈值内无更新的记录
批量标终态（job→failed、asset→error），并返回 (job_id, celery_task_id)
列表供调用方 revoke + purge 残留队列消息。
"""

from __future__ import annotations

import logging
from collections.abc import Callable
from datetime import UTC, datetime, timedelta
from typing import Any

logger = logging.getLogger(__name__)

# ingest_job PROCESSING 超时阈值：ingest 任务包含下载 + ffprobe + HEVC 转码
# （1GB 视频约 10-20 分钟）+ 回传 OSS，正常任务可能跑 20-30 分钟；
# 60 分钟阈值覆盖大文件转码 + 抖动，绝不误杀正常任务。
INGEST_PROCESSING_TIMEOUT_MINUTES = 60

# ingest_job PENDING 超时阈值：transcode 队列 concurrency=1，队列积压时
# 正常排队可能较久；90 分钟覆盖 worker 短暂停消费 + 排队。
INGEST_PENDING_TIMEOUT_MINUTES = 90

# Asset 占位超时阈值：无关联 ingest_job 的孤儿占位（complete 预建后派单失败等），
# 阈值放宽到 120 分钟，避免与 ingest_job 生命周期错杀。
ASSET_ORPHAN_TIMEOUT_MINUTES = 120

_TERMINAL_JOB_STATUSES = ("failed", "completed")
_TERMINAL_ASSET_STATUSES = ("ready", "error", "deleted")


def _now() -> datetime:
    return datetime.now(UTC)


def cleanup_stale_ingest_jobs(
    session: Any,
    *,
    processing_timeout_minutes: int = INGEST_PROCESSING_TIMEOUT_MINUTES,
    pending_timeout_minutes: int = INGEST_PENDING_TIMEOUT_MINUTES,
    commit: bool = True,
) -> tuple[list[tuple[str, str]], list[str]]:
    """清理超时卡 pending/processing 的 ingest_jobs，并联动关联 asset。

    Args:
        session: SQLAlchemy session（或提供 query/commit 的鸭子类型）
        processing_timeout_minutes: processing 状态超时阈值
        pending_timeout_minutes: pending 状态超时阈值
        commit: 是否提交事务

    Returns:
        (job_items, asset_ids)
        - job_items: [(job_id, celery_task_id), ...] 供 revoke/purge
        - asset_ids: 被联动标记为 error 的 asset id 列表
    """
    from packages.adapters.sqlalchemy_impl.models import AssetModel, IngestJobModel

    now = _now()
    processing_cutoff = now - timedelta(minutes=processing_timeout_minutes)
    pending_cutoff = now - timedelta(minutes=pending_timeout_minutes)

    stale_jobs = (
        session.query(IngestJobModel)
        .filter(
            IngestJobModel.status.in_(["pending", "processing"]),
            (
                (IngestJobModel.status == "processing") & (IngestJobModel.updated_at < processing_cutoff)
                | (IngestJobModel.status == "pending") & (IngestJobModel.created_at < pending_cutoff)
            ),
        )
        .all()
    )

    job_items: list[tuple[str, str]] = []
    asset_ids: list[str] = []
    stale_asset_models: list[Any] = []
    for job_model in stale_jobs:
        ref_time = job_model.updated_at or job_model.created_at
        if ref_time.tzinfo is None:  # SQLite 读回 naive datetime 的防御
            ref_time = ref_time.replace(tzinfo=UTC)
        stale_minutes = int((now - ref_time).total_seconds() // 60)
        job_model.status = "failed"
        job_model.error_message = (
            f"转码任务执行中断（超过超时阈值未更新，疑似 worker 重启/进程退出，已卡死 {stale_minutes} 分钟）"
        )
        job_model.updated_at = now
        job_items.append((job_model.id, getattr(job_model, "celery_task_id", "") or ""))
        if job_model.asset_id:
            asset_ids.append(job_model.asset_id)

    if asset_ids:
        stale_asset_models = (
            session.query(AssetModel)
            .filter(
                AssetModel.id.in_(asset_ids),
                AssetModel.status.in_(["processing", "uploading"]),
            )
            .all()
        )
        for asset_model in stale_asset_models:
            asset_model.status = "error"
            asset_model.updated_at = now

    if commit and (job_items or stale_asset_models):
        session.commit()

    if job_items:
        logger.warning(
            "[ingest-cleanup] 清理 %d 个超时 ingest_job（processing>%dm / pending>%dm），联动 %d 个 asset 标 error",
            len(job_items),
            processing_timeout_minutes,
            pending_timeout_minutes,
            len(stale_asset_models),
        )
    return job_items, [a.id for a in stale_asset_models]


def cleanup_orphan_processing_assets(
    session: Any,
    *,
    timeout_minutes: int = ASSET_ORPHAN_TIMEOUT_MINUTES,
    commit: bool = True,
) -> list[str]:
    """清理无 ingest_job 关联、超时卡 processing/uploading 的孤儿 asset 占位。

    complete 阶段预建 asset 后若派单失败（或 direct 上传 complete 后
    未触发 ingest），占位会永久卡住。这类 asset 没有对应 ingest_job，
    只能按 created_at 超时兜底标 error。
    """
    from packages.adapters.sqlalchemy_impl.models import AssetModel, IngestJobModel

    cutoff = _now() - timedelta(minutes=timeout_minutes)
    orphan_assets = (
        session.query(AssetModel)
        .outerjoin(IngestJobModel, IngestJobModel.asset_id == AssetModel.id)
        .filter(
            AssetModel.status.in_(["processing", "uploading"]),
            AssetModel.created_at < cutoff,
            IngestJobModel.id.is_(None),
        )
        .all()
    )
    for asset_model in orphan_assets:
        asset_model.status = "error"
        asset_model.updated_at = _now()
    if commit and orphan_assets:
        session.commit()
        logger.warning("[ingest-cleanup] 清理 %d 个无 job 关联的超时孤儿 asset 占位", len(orphan_assets))
    return [a.id for a in orphan_assets]


def revoke_stale_ingest_messages(
    job_items: list[tuple[str, str]],
    *,
    celery_app_factory: Callable[[], Any] | None = None,
    broker_url_factory: Callable[[], str] | None = None,
) -> int:
    """revoke + 物理清理 ingest 作废消息（transcode/celery 队列）。

    消息可能已在 worker 宕机时丢失（队列里查不到），那也无害；
    若消息还在（极端重复投递），物理清除防止重投执行。
    失败不阻断清理（ingest_asset 的执行前状态守卫是第二道防线）。
    """
    biz_ids = [jid for jid, _ in job_items if jid]
    celery_ids = [cid for _, cid in job_items if cid]
    if not biz_ids and not celery_ids:
        return 0
    try:
        from packages.shared.celery_orphan_guard import revoke_and_purge

        app = celery_app_factory() if celery_app_factory else None
        broker_url = broker_url_factory() if broker_url_factory else ""
        if app is None or not broker_url:
            from worker_app.celery_app import celery_app as _app
            from worker_app.core.config import get_settings

            app = _app
            broker_url = get_settings().broker_url
        return revoke_and_purge(
            app,
            broker_url,
            business_task_ids=biz_ids,
            celery_task_ids=celery_ids,
            queue_names=("transcode", "celery"),
        )
    except Exception as e:  # noqa: BLE001
        logger.error("撤销作废 ingest 队列消息失败（执行前守卫仍会兜底）: %s", e, exc_info=True)
        return 0


# ── worker 启动恢复（#1714）──────────────────────────────────────────────
#
# task_acks_late=True 下，worker 崩溃/容器重启时未 ack 的消息理论上会在
# visibility_timeout 到期后重新投递；但 prefork 进程异常、部署窗口跨
# visibility 配置边界等场景仍可能留下卡在 processing 的 ingest_job
# （staging 实证：03:16 派单、03:45 置 processing 后 worker 重启，
# unacked 消息未重投，任务永久卡死）。启动时做一次显式恢复扫描兜底。
#
# 恢复策略：processing 超过 stuck_minutes（默认 10 分钟，部署中跨进程
# 交接的正常窗口 < 10 分钟，不会误抢别的 worker 正在执行的任务）的 job，
# CAS 重置为 pending 并重新 send_task；旧消息若后来重投，ingest_asset
# 的执行前守卫会把状态不匹配的旧 celery 消息丢弃。


def recover_stuck_ingest_jobs_on_startup(
    session: Any,
    *,
    send_task: Callable[..., Any] | None = None,
    update_celery_task_id: Callable[[str, str], None] | None = None,
    lock_acquire: Callable[[], bool] | None = None,
    stuck_minutes: int = 10,
    commit: bool = True,
) -> int:
    """worker 启动时把卡在 processing 超时的 ingest_job 重新派单。

    Args:
        session: SQLAlchemy session
        send_task: celery send_task 可调用（注入便于测试）；不传则用 worker celery_app
        update_celery_task_id: 回写新 celery task id 的回调（job_id, new_task_id）
        lock_acquire: 分布式锁获取回调（多 worker 进程同时启动时只允许一个恢复）；
            返回 False 表示未抢到锁，本次跳过
        stuck_minutes: processing 超过该分钟数视为卡死

    Returns:
        重新派单的 job 数
    """
    if lock_acquire is not None and not lock_acquire():
        logger.info("[ingest-recover] 未抢到恢复锁，跳过（另一进程正在恢复）")
        return 0

    from packages.adapters.sqlalchemy_impl.models import IngestJobModel

    cutoff = _now() - timedelta(minutes=stuck_minutes)
    stuck_jobs = (
        session.query(IngestJobModel)
        .filter(IngestJobModel.status == "processing", IngestJobModel.updated_at < cutoff)
        .order_by(IngestJobModel.updated_at.asc())
        .all()
    )

    if not stuck_jobs:
        logger.info("[ingest-recover] 无卡死 processing ingest_job 需要恢复")
        return 0

    if send_task is None:
        from worker_app.celery_app import celery_app as _app

        send_task = _app.send_task

    recovered = 0
    for job_model in stuck_jobs:
        # CAS：只有仍是 processing 才重置（并发/旧消息已回写终态时不碰）
        updated = (
            session.query(IngestJobModel)
            .filter(IngestJobModel.id == job_model.id, IngestJobModel.status == "processing")
            .update({"status": "pending", "error_message": "", "updated_at": _now()})
        )
        if not updated:
            continue
        try:
            result = send_task("worker.ingest_asset", args=[job_model.id])
            new_task_id = getattr(result, "id", "") or ""
        except Exception as e:  # noqa: BLE001
            logger.error("[ingest-recover] 重新派单失败 job_id=%s: %s", job_model.id, e)
            continue
        if new_task_id:
            job_model.celery_task_id = new_task_id
            if update_celery_task_id is not None:
                update_celery_task_id(job_model.id, new_task_id)
        logger.warning(
            "[ingest-recover] 卡死 ingest_job %s 已重置 pending 并重新派单 (new celery task=%s)",
            job_model.id,
            new_task_id,
        )
        recovered += 1

    if commit and recovered:
        session.commit()
    logger.warning("[ingest-recover] 启动恢复完成，共重新派单 %d 个卡死 ingest_job", recovered)
    return recovered


def make_redis_recovery_lock(lock_key: str = "ingest:recover:startup", ttl_seconds: int = 300):
    """构造基于 Redis SET NX 的恢复锁工厂（多 worker 进程互斥）。

    返回一个无参 callable，调用时尝试抢锁：抢到返回 True，未抢到返回 False。
    Redis 不可用时不阻断启动恢复（返回 True，恢复逻辑自身有 CAS 幂等保护）。
    """

    def _acquire() -> bool:
        try:
            import redis as redis_lib
            from worker_app.core.config import get_settings

            client = redis_lib.Redis.from_url(get_settings().broker_url)
            return bool(client.set(lock_key, "1", nx=True, ex=ttl_seconds))
        except Exception as e:  # noqa: BLE001
            logger.warning("[ingest-recover] Redis 锁不可用，降级为无锁执行（CAS 兜底）: %s", e)
            return True

    return _acquire