"""WebSocket proxy: authenticated web users ↔ Tracker WS."""

import asyncio
import json
import logging

from fastapi import APIRouter, WebSocket, WebSocketDisconnect
import websockets

from auth import verify_token
from config import TRACKER_WS_URL, TRACKER_TOKEN

logger = logging.getLogger("bff.ws")
router = APIRouter()


@router.websocket("/ws")
async def ws_proxy(ws: WebSocket, token: str = ""):
    # Authenticate user
    if not token:
        await ws.close(code=4001, reason="No token")
        return
    user = verify_token(token)
    if not user:
        await ws.close(code=4001, reason="Invalid token")
        return

    await ws.accept()
    user_name = user.get("name", "unknown")
    user_slug = user.get("sub", "admin")
    logger.info("WS connected: %s (%s)", user_name, user_slug)

    try:
        async with websockets.connect(TRACKER_WS_URL) as tracker_ws:
            # Send auth to tracker on behalf of user
            auth_msg = json.dumps({
                "type": "auth",
                "token": TRACKER_TOKEN,
            })
            await tracker_ws.send(auth_msg)

            # Wait for auth.ok
            auth_resp = await tracker_ws.recv()
            auth_data = json.loads(auth_resp)
            if auth_data.get("type") != "auth.ok":
                logger.error("Tracker auth failed: %s", auth_data)
                await ws.close(code=4002, reason="Tracker auth failed")
                return

            # Forward auth.ok to client
            await ws.send_text(auth_resp)

            async def forward_to_tracker():
                try:
                    while True:
                        data = await ws.receive_text()
                        await tracker_ws.send(data)
                except WebSocketDisconnect:
                    pass

            async def forward_to_client():
                try:
                    async for msg in tracker_ws:
                        await ws.send_text(msg)
                except Exception:
                    pass

            await asyncio.gather(forward_to_tracker(), forward_to_client())
    except Exception as e:
        logger.error("WS proxy error: %s", e)
    finally:
        logger.info("WS disconnected: %s", user_name)