class MCRcon(object):
    def __init__(self, host, port, password):
        self.host = host
        self.port = port
        self.password = password
        self.socket = None

    def connect(self):
        if self.socket is not None:
            raise MCRconException("Already connected")
        self.socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        self.socket.connect((self.host, self.port))
        self.send(3, self.password)
        self.socket.settimeout(0.1)

    def disconnect(self):
        if self.socket is None:
            raise MCRconException("Already disconnected")
        self.socket.close()
        self.socket = None

    def reconnect(self, retry=True):
        try:
            self.disconnect()
            self.connect()
        except ConnectionRefusedError:
            time.sleep(5)
            if retry: self.reconnect()

    def read_response(self):
        try:
            re = self.socket.recv(4096)
            if re == b'':
                self.reconnect()

            else:
                Packet = collections.namedtuple("Packet", ("ident", "kind", "payload"))
                length = struct.unpack("<i", re[:4])[0] + 4

                ident, kind = struct.unpack("<ii", re[4:12])
                payload, padding = re[12:length-2], re[length-2:length]
                assert padding == b"\x00\x00"
                return payload.decode("utf-8")

        except socket.timeout:
            return None
        except TimeoutError:
            return None

    def send(self, out_type, out_data):
        if self.socket is None:
            raise MCRconException("Must connect before sending data")

        out_payload = struct.pack('<ii', 0, out_type) + out_data.encode('utf8') + b'\x00\x00'
        out_length = struct.pack('<i', len(out_payload))
        self.socket.send(out_length + out_payload)

        return self.read_response()

    def listen(self):
        while True:
            yield self.read_response()

    def command(self, command):
        response = self.send(2, command)
        time.sleep(0.003)
        return response