import structlog
from fastapi import APIRouter, Request, Response

router = APIRouter()
logger = structlog.get_logger("aoc.webhooks")


@router.post("/webhooks/graph")
async def graph_webhook(request: Request):
    """
    Receive Microsoft Graph change notifications.
    Handles the validation handshake by echoing validationToken.
    """
    validation_token = request.query_params.get("validationToken")
    if validation_token:
        return Response(content=validation_token, media_type="text/plain")

    try:
        body = await request.json()
    except Exception as exc:
        logger.warning("Invalid webhook payload", error=str(exc))
        return Response(status_code=400)

    for notification in body.get("value", []):
        logger.info(
            "Received Graph notification",
            change_type=notification.get("changeType"),
            resource=notification.get("resource"),
            client_state=notification.get("clientState"),
        )

    return {"status": "accepted"}