import logging
from typing import List
import httpx
from fastapi import FastAPI, Request, Response, HTTPException
from starlette.status import HTTP_502_BAD_GATEWAY
from alien_gateway.config import settings

app = FastAPI(
    title=f"{settings.PROJECT_NAME} - Gateway & Auth Service",
    version="1.0.0"
)

logger = logging.getLogger("alien_gateway")

@app.get("/health")
async def health():
    return {"service": "alien_gateway", "status": "ok"}

# 此模块未来将承担 JWT 签发、权限校验中间件、路由聚合等核心功能
@app.post("/auth/login")
async def login():
    return {"message": "Auth logic here"}


HOP_BY_HOP_HEADERS: List[str] = [
    "connection",
    "keep-alive",
    "proxy-authenticate",
    "proxy-authorization",
    "te",
    "trailers",
    "transfer-encoding",
    "upgrade",
]


def _clean_headers(headers):
    """移除 hop-by-hop 头，避免转发问题。"""
    return {k: v for k, v in headers.items() if k.lower() not in HOP_BY_HOP_HEADERS}


@app.api_route("/api/store/{full_path:path}", methods=["GET", "POST", "PUT", "PATCH", "DELETE", "OPTIONS"])
async def proxy_to_store(full_path: str, request: Request):
    """
    简易网关：监听 33333 端口，将 /api/store/* 转发到 alien_store 服务。
    """
    target_url = f"{settings.STORE_BASE_URL}/api/store/{full_path}"
    client_ip = request.client.host if request.client else "-"

    # 读取请求体
    body = await request.body()

    # 过滤头部
    headers = _clean_headers(dict(request.headers))

    try:
        async with httpx.AsyncClient(timeout=30.0) as client:
            resp = await client.request(
                request.method,
                target_url,
                content=body,
                headers=headers,
                params=request.query_params,
            )
    except Exception as exc:
        logger.error("proxy to store failed ip=%s url=%s err=%s", client_ip, target_url, exc)
        raise HTTPException(status_code=HTTP_502_BAD_GATEWAY, detail="Upstream unavailable")

    # 返回下游响应
    return Response(
        content=resp.content,
        status_code=resp.status_code,
        headers=_clean_headers(resp.headers),
        media_type=resp.headers.get("content-type"),
    )

if __name__ == "__main__":
    import uvicorn
    uvicorn.run(app, host="0.0.0.0", port=33333)