"""FastAPI 应用入口。"""
from __future__ import annotations

import asyncio
import logging
from contextlib import asynccontextmanager
from typing import AsyncIterator

from fastapi import FastAPI

from app.exception_handlers import register_exception_handlers
from app.response import ApiResponse
from app.routers import search
from app.schemas import CacheRefreshResult, CacheStatus
from app.services.cache import faq_cache, scheduler_loop

logging.basicConfig(
    level=logging.INFO,
    format="%(asctime)s | %(levelname)s | %(name)s | %(message)s",
)
logger = logging.getLogger(__name__)


@asynccontextmanager
async def lifespan(app: FastAPI) -> AsyncIterator[None]:
    """启动时初始化缓存 + 启动定时器；关闭时优雅取消。"""
    logger.info("启动：首次加载 FAQ 缓存…")
    await faq_cache.refresh()

    task = asyncio.create_task(scheduler_loop(), name="faq-scheduler")
    logger.info("启动：定时刷新任务已运行")

    try:
        yield
    finally:
        logger.info("关闭：取消定时任务…")
        task.cancel()
        try:
            await task
        except asyncio.CancelledError:
            pass


app = FastAPI(
    title="Zendesk FAQ Keyword Search",
    description="封装 Zendesk Help Center 搜索；FAQ sec_ids 每日 0 点刷新缓存。",
    version="1.0.0",
    lifespan=lifespan,
)

# 注册全局异常处理器（统一错误响应格式 {code, data, msg}）
register_exception_handlers(app)

# 路由
app.include_router(search.router)


@app.get(
    "/health",
    response_model=ApiResponse[dict[str, str]],
    tags=["meta"],
)
async def health() -> ApiResponse[dict[str, str]]:
    """健康检查。"""
    return ApiResponse.ok(data={"status": "ok"})


@app.get(
    "/health/cache",
    response_model=ApiResponse[CacheStatus],
    tags=["meta"],
)
async def cache_status() -> ApiResponse[CacheStatus]:
    """缓存状态查看。"""
    snap = faq_cache.snapshot()
    return ApiResponse.ok(
        data=CacheStatus(
            sec_ids_count=len(snap["sec_ids"]),
            last_updated_at=snap["last_updated_at"],
            next_refresh_at=snap["next_refresh_at"],
        )
    )


@app.post(
    "/admin/cache/refresh",
    response_model=ApiResponse[CacheRefreshResult],
    tags=["meta"],
)
async def refresh_cache_now() -> ApiResponse[CacheRefreshResult]:
    """手动触发刷新（运维 / 测试用途）。"""
    await faq_cache.refresh()
    snap = faq_cache.snapshot()
    return ApiResponse.ok(
        data=CacheRefreshResult(
            sec_ids_count=len(snap["sec_ids"]),
            last_updated_at=snap["last_updated_at"],
        ),
        msg="缓存刷新成功",
    )