import time
from contextlib import asynccontextmanager

from fastapi import FastAPI, Request
from fastapi.middleware.cors import CORSMiddleware
from fastapi.middleware.gzip import GZipMiddleware

from common.database.db_session_manager import DB_SESSION_MNG
from common.logger import LOG
from common.utils.gtime import GTime
from config.server_configs import web_server_config
import router.v1.auth.account
import router.v1.negotiation.session
import router.v1.chat.chat

API_SERVER_START_TIME = GTime.UTCStr()


@asynccontextmanager
async def lifespan(app: FastAPI):
    # startup
    yield
    # shutdown: DB 엔진 커넥션 풀 정리
    await DB_SESSION_MNG.dispose_all()


app = FastAPI(title="Negosium Api Server", lifespan=lifespan)

# CORS: config 의 cors_origins 가 있을 때만 적용(브라우저 프론트 호출 허용).
# 명시적 오리진을 쓰므로 allow_credentials=True 가능(쿠키/Authorization 헤더 허용).
if web_server_config.cors_origins:
    app.add_middleware(
        CORSMiddleware,
        allow_origins=web_server_config.cors_origins,
        allow_credentials=True,
        allow_methods=["*"],
        allow_headers=["*"],
    )

# Accept-Encoding: gzip 요청에 대해 1000 bytes 이상 응답을 압축.
app.add_middleware(GZipMiddleware, minimum_size=1000)


@app.middleware("http")
async def log_time(request: Request, call_next):
    start_time = time.time()
    response = await call_next(request)
    elapsed = time.time() - start_time
    LOG.d(f"took: {elapsed:.4f} - {request.url.path}")
    return response


@app.get(
    path="/healthz",
    summary="헬스체크",
    description="서버 기동 시각(API_SERVER_START_TIME)을 반환하는 헬스체크 엔드포인트.",
    responses={404: {"description": "Not found"}},
)
async def healthz():
    return API_SERVER_START_TIME


# 각 도메인 라우터를 등록한다. 새 기능 추가 시 router.v1.<domain>.<file> 를 import 후 include.
app.include_router(router.v1.auth.account.router)
app.include_router(router.v1.negotiation.session.router)
app.include_router(router.v1.chat.chat.router)