from __future__ import annotations

import json

from channels.generic.websocket import WebsocketConsumer

from .common import CONTROL_PACKET_SIZE, CONTROL_SOURCE_WEB
from .services import control_arbiter, native_control_ingress


class ControlConsumer(WebsocketConsumer):
    def connect(self) -> None:
        control_arbiter.ensure_started()
        native_control_ingress.ensure_started()
        self.accept()
        self.send(
            text_data=json.dumps(
                {
                    "type": "ready",
                    "packet_bytes": CONTROL_PACKET_SIZE,
                }
            )
        )

    def receive(self, text_data: str | None = None, bytes_data: bytes | None = None) -> None:
        if bytes_data is None:
            self.send(text_data=json.dumps({"type": "error", "detail": "binary control payload required"}))
            return

        if len(bytes_data) != CONTROL_PACKET_SIZE:
            self.send(
                text_data=json.dumps(
                    {
                        "type": "error",
                        "detail": f"expected {CONTROL_PACKET_SIZE} bytes, got {len(bytes_data)}",
                    }
                )
            )
            return

        control_arbiter.ingest_command(CONTROL_SOURCE_WEB, bytes_data)