import zmq


class ZmqPubSubStreamer:
    '''
    Not thread-safe. Always get this inside the thread/process where you intend
    to use it. 
    '''

    def __init__(self, port):
        self._socket = zmq.Context.instance().socket(zmq.PUB)
        print('Starting socket with address: ' + 'tcp://*:' + str(port))
        self._socket.bind("tcp://*:" + str(port))
        

    def send_message(self, message):
        '''
        Args
        ----
        message: A message type that has the serialise() method.
        '''
        self.send_message_topic("", message)

    def send_message_topic(self, topic, message):
        self._socket.send_multipart([bytes(topic), message.serialise()])


class BluetoothStreamer:
    def __init__(self):
        pass

    def send_message(self, message_bytes):
        pass

class TestStreamer:
    def __init__(self):
        self._listeners = []

    def send_message(self, message_bytes):
        print('Got a message')

    def send_message_topic(self, topic, message):
        print('Got a message with topic: ' + str(topic))
        self._fire_message_received(message)

    def add_message_listener(self, listener):
        self._listeners.append(listener)

    def _fire_message_received(self, message):
        for listener in self._listeners:
            listener(message)

def getZmqPubSubStreamer(port):
    '''
    Not thread-safe. Always get this inside the thread/process where you intend
    to use it. 
    '''
    return ZmqPubSubStreamer(port)

def getTestingStreamer():
    return TestStreamer()