from fastapi import FastAPI, Request, Header, HTTPException
from fastapi.responses import JSONResponse, Response
import httpx
import socket

app = FastAPI()

# Real secret API key (used internally, never exposed)
REAL_API_KEY = "sk-94NDKhKQkhKoYnY65mg4NAIFK5BqNiCtxo8u3PsDpb0IucZt"
BASE_URL = "https://fast.typegpt.net"

# Public key that users must use in Authorization header
PUBLIC_AUTH_TOKEN = "TypeGPT-Free4ALL"

# Show server IP at startup
@app.on_event("startup")
async def startup_event():
    try:
        hostname = socket.gethostname()
        server_ip = socket.gethostbyname(hostname)
        print("===== Server Started =====")
        print(f"📡 Server IP: {server_ip}")
    except Exception as e:
        print(f"⚠️ Could not determine server IP: {e}")

@app.api_route("/{path:path}", methods=["GET", "POST"])
async def proxy(request: Request, path: str, authorization: str = Header(None)):
    # Validate Authorization token
    if not authorization or not authorization.startswith("Bearer "):
        raise HTTPException(status_code=401, detail="Missing or malformed Authorization header.")

    token = authorization.replace("Bearer ", "").strip()
    if token != PUBLIC_AUTH_TOKEN:
        raise HTTPException(status_code=401, detail="Invalid Authorization token. Use 'TypeGPT-Free4ALL'.")

    # Rebuild the target URL
    target_url = f"{BASE_URL}/{path}"

    # Use clean headers to avoid Cloudflare issues
    headers = {
        "Authorization": f"Bearer {REAL_API_KEY}",
        "Content-Type": request.headers.get("content-type", "application/json"),
        "Accept": "application/json",
        "User-Agent": "FastAPI-Proxy"
    }

    # Read the body
    body = await request.body()

    # Log for debugging
    print(f"🔄 Forwarding to: {target_url}")
    print(f"📦 Request Body (first 200 chars): {body[:200]}")

    async with httpx.AsyncClient() as client:
        try:
            response = await client.request(
                method=request.method,
                url=target_url,
                headers=headers,
                content=body,
                timeout=60
            )
        except httpx.RequestError as e:
            raise HTTPException(status_code=502, detail=f"Failed to reach backend: {e}")

    print(f"↩️ TypeGPT Status: {response.status_code}")
    print(f"🧾 Response Snippet: {response.text[:200]}")

    # Return JSON if possible, else fallback
    try:
        return JSONResponse(content=response.json(), status_code=response.status_code)
    except Exception:
        return Response(
            content=response.content,
            status_code=response.status_code,
            media_type=response.headers.get("content-type", "text/plain")
        )