import datetime
import json
import time

from services.mqtt_service import MQTTService

class MQTTForwarder:

    client_id : str
    local_broker : MQTTService
    central_broker : MQTTService

    def __init__(self, client_id : str, local_mqtt: MQTTService, central_mqtt: MQTTService):
        self.client_id = client_id
        self.local_broker = local_mqtt
        self.central_broker = central_mqtt

    def start(self, src_topic: str, dst_topic: str):
        try:
            def forward_handler(topic: str, msg: str):
                forwarded_msg = self.__wrapData(msg)
                self.central_broker.publish(dst_topic, forwarded_msg)

            self.local_broker.subscribe(src_topic, forward_handler)
        except Exception as e:
            print(f"An error occurred while forwarding from {src_topic} to {dst_topic}: {e}")

    def __wrapData(self, msg : str):
        result = {}
        data = json.loads(msg)
        result["timestamp"] = int(time.time())
        result["systemId"] = self.client_id
        result["data"] = {}
        for keys in data:
            result["data"][keys] = data[keys]