import asyncio
from collections.abc import AsyncGenerator
from typing import Annotated, Any

from fastapi import APIRouter, Depends, Request
from fastapi.responses import JSONResponse
from fastapi.sse import EventSourceResponse, ServerSentEvent
from fastapi_limiter.decorators import skip_limiter

from app.common.response import ResponseSchema, SuccessResponse
from app.config.setting import Settings, get_settings
from app.core.logger import logger
from app.core.router_class import OperationLogRoute

from .schema import ServiceInfoOut
from .service import HealthService

HealthRouter = APIRouter(route_class=OperationLogRoute, prefix="/health", tags=["健康检查"])


@HealthRouter.get("/check", summary="健康检查", response_model=ResponseSchema[ServiceInfoOut])
@skip_limiter  # 监控探针高频调用，豁免全局限流
async def health_check(request: Request, settings: Annotated[Settings, Depends(get_settings)]) -> JSONResponse:
    """健康检查：实时探测 DB / Redis 网络连通状态。"""
    redis: Any | None = getattr(request.app.state, "redis", None)
    info = await HealthService.collect(redis)
    ok = info.db_status == 1 and info.redis_status == 1
    return SuccessResponse(data=info, msg=f"系统健康-{settings.VERSION}" if ok else f"服务异常-{settings.VERSION}")



@HealthRouter.get("/stream", summary="健康检查实时流(SSE)", response_class=EventSourceResponse)
@skip_limiter
async def health_stream_controller(
    request: Request,
) -> AsyncGenerator[ServerSentEvent, None]:
    """健康检查实时流（SSE）：每 30s 实时探测 DB / Redis 后推送一帧。"""
    redis: Any | None = getattr(request.app.state, "redis", None)
    while True:
        info = await HealthService.collect(redis)
        # raw_data 原样发送；用 data= 会被 fastapi.sse 再 JSON 编码一次，前端需二次解析
        logger.debug(
            "健康检查 SSE 推送: DB={} Redis={}",
            "正常" if info.db_status == 1 else "异常",
            "正常" if info.redis_status == 1 else "异常",
        )
        yield ServerSentEvent(raw_data=info.model_dump_json())
        await asyncio.sleep(30) # SSE 推送间隔（秒）