from fastapi import FastAPI, Request

app = FastAPI()

@app.get("/")
async def read_root(request: Request):
    ip = request.client.host
    print("访问者 IP:", ip)
    return {"ip": ip}

# save as app_fastapi.py
from fastapi import FastAPI, Request
from pydantic import BaseModel
import httpx  # pip install fastapi uvicorn httpx

app = FastAPI()

class WhoamiResp(BaseModel):
    client_ip: str
    user_agent: str | None
    accept_language: str | None
    headers: dict
    geo: dict | None = None

def get_client_ip_from_request(req: Request) -> str:
    headers = req.headers
    xff = headers.get("x-forwarded-for")
    if xff:
        return xff.split(",")[0].strip()
    xr = headers.get("x-real-ip")
    if xr:
        return xr
    # starlette Request.scope 中有 client tuple
    client = req.client
    return client.host if client else ""

async def ip_geolocate_async(ip: str):
    if not ip:
        return None
    try:
        async with httpx.AsyncClient(timeout=2.0) as client:
            r = await client.get(f"http://ip-api.com/json/{ip}")
            if r.status_code == 200:
                data = r.json()
                if data.get("status") == "success":
                    return {
                        "country": data.get("country"),
                        "region": data.get("regionName"),
                        "city": data.get("city"),
                        "lat": data.get("lat"),
                        "lon": data.get("lon"),
                        "isp": data.get("isp"),
                    }
    except Exception:
        pass
    return None

@app.get("/whoami", response_model=WhoamiResp)
async def whoami(request: Request):
    ip = get_client_ip_from_request(request)
    ua = request.headers.get("user-agent")
    accept_lang = request.headers.get("accept-language")
    headers = dict(request.headers)
    geo = await ip_geolocate_async(ip)  # 可选
    return WhoamiResp(client_ip=ip, user_agent=ua, accept_language=accept_lang, headers=headers, geo=geo)

# 启动： uvicorn app_fastapi:app --host 0.0.0.0 --port 8000 --reload