"""Worker 进程模块

基于 Redis 队列的任务 Worker，支持分布式锁和全局并发控制。
"""

import asyncio
import logging
import signal
import sys
from typing import Optional

from .config import settings
from .core.job_manager import JobManager
from .core.logging import setup_logging
from .core.tracing import set_request_id

logger = logging.getLogger(__name__)


class JobWorker:
    """任务 Worker

    从 Redis 队列获取任务并执行，支持：
    - 分布式锁防止重复执行
    - 全局并发控制
    - 任务重试机制
    - 优雅关闭
    """

    def __init__(self):
        self._job_manager: Optional[JobManager] = None
        self._running: bool = False
        self._current_job_id: Optional[str] = None

    async def initialize(self) -> None:
        """初始化 Worker"""
        self._job_manager = JobManager()
        await self._job_manager.initialize()
        logger.info("Worker 初始化完成")

    async def shutdown(self) -> None:
        """关闭 Worker"""
        logger.info("Worker 正在关闭...")
        self._running = False

        # 等待当前任务完成
        if self._current_job_id:
            logger.info(f"等待当前任务完成: {self._current_job_id}")

        if self._job_manager:
            await self._job_manager.shutdown()

        logger.info("Worker 已关闭")

    async def run(self) -> None:
        """运行 Worker 主循环"""
        self._running = True
        logger.info(
            f"Worker 启动，轮询间隔: {settings.worker_poll_interval}s，"
            f"最大并发: {settings.max_concurrent_jobs}"
        )

        while self._running:
            try:
                await self._process_next_job()
            except Exception as e:
                logger.error(f"Worker 循环异常: {e}", exc_info=True)
                await asyncio.sleep(settings.worker_poll_interval)

    async def _process_next_job(self) -> None:
        """处理下一个任务"""
        if not self._job_manager:
            logger.error("JobManager 未初始化")
            await asyncio.sleep(settings.worker_poll_interval)
            return

        # 从队列获取任务
        job_id = await self._job_manager.dequeue_job(timeout=int(settings.worker_poll_interval))

        if not job_id:
            return

        # 获取任务信息以提取 request_id
        job_data = await self._job_manager.get_job(job_id)
        if job_data:
            request_id = job_data.get("request_id") or job_id
            set_request_id(request_id)
        else:
            set_request_id(job_id)

        logger.info(f"从队列获取任务: {job_id}")

        # 尝试获取分布式锁
        if not await self._job_manager.acquire_job_lock(job_id):
            logger.warning(f"无法获取任务锁，任务可能正在被其他 Worker 执行: {job_id}")
            return

        try:
            # 检查全局并发限制
            if not await self._job_manager.can_execute():
                logger.info(f"达到并发限制，任务重新入队: {job_id}")
                await self._job_manager.enqueue_job(job_id)
                return

            # 增加并发计数
            await self._job_manager.increment_concurrency()
            self._current_job_id = job_id

            try:
                # 执行任务
                await self._execute_with_retry(job_id)
            finally:
                # 减少并发计数
                await self._job_manager.decrement_concurrency()
                self._current_job_id = None

        finally:
            # 释放分布式锁
            await self._job_manager.release_job_lock(job_id)

    async def _execute_with_retry(self, job_id: str) -> None:
        """执行任务（带重试机制）"""
        if not self._job_manager:
            return

        try:
            # 执行任务
            await asyncio.wait_for(
                self._job_manager.execute_job(job_id),
                timeout=settings.job_execution_timeout,
            )
        except asyncio.TimeoutError:
            logger.error(f"任务执行超时: {job_id}")
            await self._handle_job_failure(job_id, "任务执行超时")
        except Exception as e:
            logger.error(f"任务执行异常: {job_id}, error={e}", exc_info=True)
            await self._handle_job_failure(job_id, str(e))

    async def _handle_job_failure(self, job_id: str, error: str) -> None:
        """处理任务失败"""
        if not self._job_manager:
            return

        retry_count = await self._job_manager.increment_job_retry(job_id)

        if retry_count < settings.job_max_retries:
            logger.info(f"任务将重试 ({retry_count}/{settings.job_max_retries}): {job_id}")
            # 重新入队
            await self._job_manager.enqueue_job(job_id)
        else:
            logger.error(f"任务达到最大重试次数，标记为失败: {job_id}")
            # 更新任务状态为失败
            if self._job_manager._redis_client:
                key = f"job:{job_id}"
                await self._job_manager._redis_client.hset(
                    key,
                    mapping={
                        "status": "failed",
                        "error": f"达到最大重试次数 ({settings.job_max_retries}): {error}",
                    },
                )


def setup_signal_handlers(worker: JobWorker, loop: asyncio.AbstractEventLoop) -> None:
    """设置信号处理器"""

    def signal_handler(sig: signal.Signals) -> None:
        logger.info(f"收到信号 {sig.name}，准备关闭...")
        loop.create_task(worker.shutdown())

    for sig in (signal.SIGTERM, signal.SIGINT):
        loop.add_signal_handler(sig, signal_handler, sig)


async def main() -> None:
    """Worker 入口函数"""
    # 设置日志
    setup_logging(level=settings.log_level, format_type=settings.log_format)

    worker = JobWorker()

    # 设置信号处理
    loop = asyncio.get_running_loop()
    setup_signal_handlers(worker, loop)

    try:
        await worker.initialize()
        await worker.run()
    except Exception as e:
        logger.error(f"Worker 异常退出: {e}", exc_info=True)
        sys.exit(1)
    finally:
        await worker.shutdown()


if __name__ == "__main__":
    asyncio.run(main())