import network
import time
from machine import Pin
import dht
import ujson
from umqtt.simple import MQTTClient

from hcsr04 import HCSR04
from time import sleep

# ThingSpeak MQTT Parameters
# Replace with your ThingSpeak Channel details
THINGSPEAK_API_KEY = "RU9WMUQNNF0CQRJK"
THINGSPEAK_CHANNEL_ID = "2526318"
MQTT_BROKER = "mqtt.thingspeak.com"
MQTT_PORT = 1883  # Default port for ThingSpeak MQTT

# ESP32
sensor1 = HCSR04(trigger_pin=5, echo_pin=18, echo_timeout_us=100000)

print("Connecting to WiFi", end="")
sta_if = network.WLAN(network.STA_IF)
sta_if.active(True)
sta_if.connect('Wokwi-GUEST', '')
while not sta_if.isconnected():
    print(".", end="")
    time.sleep(0.1)
print(" Connected!")

# Construct the MQTT topic based on ThingSpeak details
MQTT_TOPIC = f"channels/2526318/publish/RU9WMUQNNF0CQRJK"

print("Connecting to MQTT server... ", end="")
client = MQTTClient(client_id="", server=MQTT_BROKER, port=MQTT_PORT)
client.connect()

print("Connected!")

prev_distance = ""
while True:
    distance = sensor1.distance_cm()
    print('Distance:', distance, 'cm')
    sleep(1)

    message = ujson.dumps(distance)
    if message != prev_distance:
        print("Updated!")
        print("Reporting to MQTT topic {}: {}".format(MQTT_TOPIC, message))
        client.publish(MQTT_TOPIC, message)
        prev_distance = message
    else:
        print("No change")
    time.sleep(1)