import json

from fastapi import APIRouter, Depends, Request
from fastapi.responses import StreamingResponse

from app.api import deps
from app.core.events import redis_client
from app.models import OrgRole, User

router = APIRouter()


@router.get("/project/{project_id}/stream", summary="Real-Time SSE Stream")
async def project_stream(
    project_id: str,
    client_id: str,
    request: Request,
    token: str,
    current_user: User = Depends(
        deps.require_org_role_sse(
            OrgRole.ORG_ADMIN, OrgRole.RESPO_BENEVOLE, OrgRole.RESPO_COMMISSION
        )
    ),
):
    """
    Connect to this endpoint to receive real-time updates.

    **Required Query Parameters:**
    - `client_id`: A unique UUID generated by the frontend to prevent echoing.
    """
    print(f"create event generator for {client_id}")

    async def event_generator():
        channel = f"project_{project_id}"
        pubsub = redis_client.pubsub()
        await pubsub.subscribe(channel)
        print(f"subscribed to {channel}")
        try:
            async for event in pubsub.listen():
                if event["type"] != "message":
                    continue
                if await request.is_disconnected():
                    print("disconnected")
                    break
                message = json.loads(event["data"])
                if message.get("client_id") == client_id:
                    continue
                yield f"data: {json.dumps({'event': message['event'], 'item': message['item']})}\n\n"
        finally:
            await pubsub.unsubscribe(channel)
            await pubsub.aclose()
            print(f"unsubscribed from {channel}")

    print(f"return event generator for {client_id}")
    # Return as text/event-stream so the browser knows it's an ongoing connection
    return StreamingResponse(event_generator(), media_type="text/event-stream")