import paho.mqtt.client as mqtt
import json, time, jwt, getpass, socket, random

#  mqtt auth stuff
MQTT_CLIENT_HOST = ""
MQTT_CLIENT_PORT = 1883

# device config
dev_name = getpass.getuser()
dev_id = socket.gethostname()

class MSG_Constructor:

    def __init__(self):
        pass

    # create a simple  json object
    def create_object(self):
        self.object = {
            "device": dev_name,
            "device_id": dev_id,
            "message": random.choice("ON", "OFF", "IDLING")
            }

        return self.object

    # publish message
    def publish(self, topic, message):
        try:
            self.topic = topic
            self.message = message or self.create_object

            # Try to publish the message to mqtt broker
            client.publish(self.topic, self.message)
            return True

        except KeyError:
            print('keyerror occured, request failed...')
            return False

msg_object = MSG_Constructor()

def on_connect(client, userdata, flags, rc):
    full_hostname = MQTT_CLIENT_HOST + ":" + str(MQTT_CLIENT_PORT)
    print(f"successfully connected to - {full_hostname}, as {dev_name}, code - {str(rc)}")
    client.subscribe(topic)

def on_message(client, userdata, msg):
    try:
        mqtt_message = str(msg.payload.decode('utf-8'))

        # Inside the json message object should be a client id
        mqtt_object = json.loads(mqtt_message)
        mqtt_client_id = mqtt_object["client_id"]

        if " " in mqtt_client_id or len(mqtt_client_id) < 3:
            print("Received an incorrect message, continuing")

        print(f"New message from - {mqtt_client_id}, msg - {mqtt_message}.")

    except KeyError:
        print("Received an incorrect message, continuing")
        pass

    except Exception as error:
        print(error)


def on_disconnect(self, client, userdata, rc):
    if rc != 0:
        full_hostname = MQTT_CLIENT_HOST + ":" + str(MQTT_CLIENT_PORT)
        print("Disconnected from -", full_hostname)


def on_publish(client, userdata, mid):
    print("The publish request was successfully sent to mqtt.")


def on_subscribe(client, userdata, mid, granted_qos):
    print("Successfully subscribing to -", topic)


client = mqtt.Client()
client.on_connect = on_connect
client.on_subscribe = on_subscribe
client.on_message = on_message
client.on_publish = on_publish
client.on_disconnect = on_disconnect
# client authentication
client.username_pw_set("user", "user")
topic = "/dev2" # we connect to the other dev which is on dev2

# connect to mqtt broker
client.connect(MQTT_CLIENT_HOST, MQTT_CLIENT_PORT, 600)
client.loop_forever()