from contextlib import asynccontextmanager
from time import perf_counter

from fastapi import FastAPI, Request
from fastapi.responses import JSONResponse
from fastapi.middleware.cors import CORSMiddleware

from app.api.routes import router
from app.core.config import get_settings
from app.core.logging import configure_logging, logger
from app.db.base import Base
from app.db.session import engine
from app.services.rag.lightrag_adapter import LightRAGAdapter
from app.services.runtime_state import get_ingest_queue, get_match_queue, get_traffic_guard


settings = get_settings()
configure_logging(settings.log_level)


@asynccontextmanager
async def lifespan(_: FastAPI):
    Base.metadata.create_all(bind=engine)
    get_ingest_queue().start()
    get_match_queue().start()
    try:
        LightRAGAdapter(settings).ensure_ready()
    except Exception:
        logger.exception("Qdrant initialization skipped during startup")
    yield
    get_ingest_queue().stop()
    get_match_queue().stop()


app = FastAPI(
    title=settings.app_name,
    description=(
        "Gig POC 接口文档。\n\n"
        "接口分组：系统、抽取、入库、匹配、查询。\n"
        "完整业务说明请参考项目文档 `docs/API.md`。"
    ),
    openapi_tags=[
        {"name": "系统", "description": "服务与依赖组件状态检查接口"},
        {"name": "抽取", "description": "自然语言文本抽取为结构化卡片"},
        {"name": "入库", "description": "结构化岗位/工人数据写入与初始化"},
        {"name": "匹配", "description": "岗位与工人双向匹配及结果解释"},
        {"name": "查询", "description": "岗位/工人列表与详情查询"},
    ],
    lifespan=lifespan,
)
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)


@app.middleware("http")
async def traffic_guard_middleware(request: Request, call_next):
    guard = get_traffic_guard()
    allowed, reason = guard.allow(request.url.path)
    if not allowed:
        status_code = 429 if reason == "rate_limited" else 503
        return JSONResponse(status_code=status_code, content={"detail": reason})
    start = perf_counter()
    try:
        response = await call_next(request)
    except Exception:
        guard.record(500, (perf_counter() - start) * 1000)
        raise
    guard.record(response.status_code, (perf_counter() - start) * 1000)
    return response


app.include_router(router)