import logging

from tornado.web import Application

from tfw.internals.networking import ZMQListener
from tfw.internals.server import ZMQWebSocketRouter
from tfw.config import TFWENV

LOG = logging.getLogger(__name__)


class TFWServer:
    """
    This class handles the proxying of messages between the frontend and event handers.
    It proxies messages from the "/ws" route to all event handlers subscribed to a ZMQ
    SUB socket.
    """
    def __init__(self):
        downlink_bind_addr = f'tcp://*:{TFWENV.PULL_PORT}'
        uplink_bind_addr = f'tcp://*:{TFWENV.PUB_PORT}'
        self._listener = ZMQListener(
            downlink_bind_addr=downlink_bind_addr,
            uplink_bind_addr=uplink_bind_addr
        )
        LOG.debug('Pull socket bound to %s', downlink_bind_addr)
        LOG.debug('Pub socket bound to %s', uplink_bind_addr)
        self.application = Application([(
            r'/ws', ZMQWebSocketRouter, {
                'listener': self._listener,
            }
        )])

    def listen(self):
        self.application.listen(TFWENV.WEB_PORT)