"""
v5 (GLaDOS)
===========

Description
-----------
Manage the V5 layer of GLaDOS.
"""

import logging
import socket
from threading import Thread
from functools import wraps


class V5:
    """Manage connexion beetween the bot and the V5 server, and manage callbacks.

    Attributes
    ----------
    irc : irc.IRC, public
        An IRC instance.
    
    sock : ssl.SSLSocket, private
        The V5 socket.
    handler : Thread, private
    callbacks : list, private
        List of the registred callbacks.

    Methods
    -------
    start : NoneType, public
        Start v5 handler.
    on : function, public
        Add a callback to the v5 handler.

    handle : NoneType, private
        Handle the incoming messages and callbacks.
    """

    def __init__(self, v5_params: tuple, irc):
        """Initialize V5 handle.

        Parameters
        ----------
        v5 : tuple
            The information on V5 server (host, port).
        irc : irc.IRC
            An initialized IRC instance.
        """
        self.irc = irc
        self.__sock = socket.socket(socket.AF_INET,socket.SOCK_DGRAM)
        self.__sock.bind(v5_params)
        self.__handler = Thread(target=self.__handle)
        self.__callbacks = []

    def start(self):
        """Start v5 handler."""
        self.__handler.start()
        logging.info("started")

    def on(self, event):
        """Adds a callback to the v5 handler.

        Parameters
        ----------
        event : function
            ``event`` is a function taking in parameter a list of channels and a string, and return
            ``True`` if the callback should be executed.
        """
        def callback(func):
            @wraps(func)
            def wrapper(channels, message):
                func(channels, message)
            self.__callbacks.append((event, wrapper))
            return wrapper

        return callback


    def __handle(self):
        while True:
            data, addr = self.__sock.recvfrom(4096)
            data = data.decode()
            logging.debug("received %s", data)
            channels, message = data.split(":", 1)
            channels = channels.split(" ")

            for event, callback in self.__callbacks:
                if event(channels, message):
                    logging.info("passed %s", event.__name__)
                    callback(channels, message)