1"""Django Channels WebSocket adapter."""
  2
  3import json
  4import logging
  5from uuid import uuid4
  6
  7try:
  8    from channels.generic.websocket import AsyncWebsocketConsumer
  9except ImportError as e:
 10    from . import _require_extra
 11
 12    raise _require_extra("channels", "django") from e
 13
 14from ..core.websocket import WebSocketConnection, ws_manager
 15
 16logger = logging.getLogger(__name__)
 17
 18
 19class DjangoWebSocketConnection(WebSocketConnection):
 20    """Django Channels WebSocket connection wrapper."""
 21
 22    def __init__(self, consumer: "ComponentConsumer"):
 23        self.consumer = consumer
 24
 25    async def send(self, data: dict):
 26        """Send JSON data to client."""
 27        await self.consumer.send(text_data=json.dumps(data))
 28
 29    async def receive(self) -> dict:
 30        """Receive is handled by consumer, not used directly."""
 31        raise NotImplementedError("Receive handled by consumer")
 32
 33    async def close(self):
 34        """Close WebSocket connection."""
 35        await self.consumer.close()
 36
 37
 38class ComponentConsumer(AsyncWebsocketConsumer):
 39    """
 40    Django Channels consumer for component WebSocket.
 41
 42    Usage in routing.py:
 43        from channels.routing import ProtocolTypeRouter, URLRouter
 44        from django.urls import path
 45        from component_framework.adapters.django_websocket import ComponentConsumer
 46
 47        application = ProtocolTypeRouter({
 48            "websocket": URLRouter([
 49                path("ws/", ComponentConsumer.as_asgi()),
 50            ]),
 51        })
 52    """
 53
 54    def __init__(self, *args, **kwargs):
 55        super().__init__(*args, **kwargs)
 56        self.connection_id: str | None = None
 57        self.connection: DjangoWebSocketConnection | None = None
 58
 59    async def connect(self):
 60        """Handle WebSocket connection."""
 61        # Accept connection
 62        await self.accept()
 63
 64        # Generate connection ID
 65        self.connection_id = str(uuid4())
 66        self.connection = DjangoWebSocketConnection(self)
 67
 68        # Register with manager
 69        await ws_manager.connect(self.connection, self.connection_id)
 70
 71        # Send connection confirmation
 72        await self.send(
 73            text_data=json.dumps({"type": "connected", "connection_id": self.connection_id})
 74        )
 75
 76        logger.info(f"WebSocket connected: {self.connection_id}")
 77
 78    async def disconnect(self, close_code):  # type: ignore[override]
 79        """Handle WebSocket disconnection."""
 80        if self.connection_id:
 81            await ws_manager.disconnect(self.connection_id)
 82        logger.info(f"WebSocket disconnected: {self.connection_id}")
 83
 84    async def receive(self, text_data=None, bytes_data=None):
 85        """Handle incoming WebSocket message."""
 86        if text_data is None:
 87            return
 88        try:
 89            data = json.loads(text_data)
 90            if self.connection is None or self.connection_id is None:
 91                return
 92            await ws_manager.handle_message(self.connection, self.connection_id, data)
 93        except json.JSONDecodeError:
 94            await self.send(text_data=json.dumps({"type": "error", "error": "Invalid JSON"}))
 95        except Exception as e:
 96            logger.exception("Error handling WebSocket message")
 97            await self.send(text_data=json.dumps({"type": "error", "error": str(e)}))
 98
 99
100# Channel layer helper for broadcasting
101async def broadcast_component_update(component_id: str, html: str, state: dict):
102    """
103    Broadcast component update via WebSocket manager.
104
105    Can be called from anywhere (views, signals, tasks, etc.)
106
107    Usage:
108        from component_framework.adapters.django_websocket import broadcast_component_update
109
110        # In a view or signal handler
111        await broadcast_component_update(
112            component_id="order-123",
113            html=rendered_html,
114            state={"status": "completed"}
115        )
116    """
117    await ws_manager.push_update(component_id, html, state)