#include <WiFi.h>
#include <PubSubClient.h>

#define triggerPin  19
#define echoPin     18

const char* ssid = "your_wifi_ssid";
const char* password = "your_wifi_password";
const char* mqttServer = "broker.hivemq.com";
const int mqttPort = 1883;
const char* mqttTopic = "techad/narul/jarak";

WiFiClient wifiClient;
PubSubClient mqttClient(wifiClient);

void callback(char* topic, byte* message, unsigned int length) {
  Serial.print("Callback - ");
  Serial.print("Message:");
  for (int i = 0; i < length; i++) {
    Serial.print((char)message[i]);
  }
}

void connectToWiFi() {
  Serial.print("Connecting to WiFi...");
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.println("Connecting to WiFi...");
  }
  Serial.println("Connected to WiFi");
}

void connectToBroker() {
  while (!mqttClient.connected()) {
    Serial.print("Connecting to MQTT Broker...");
    if (mqttClient.connect("ESP8266Client")) {
      Serial.println("Connected to MQTT Broker");
      mqttClient.subscribe(mqttTopic);
    } else {
      Serial.print("Failed to connect to MQTT Broker, rc=");
      Serial.print(mqttClient.state());
      Serial.println(" Retrying in 5 seconds...");
      delay(5000);
    }
  }
}

void setup() {
  Serial.begin(9600);
  pinMode(triggerPin, OUTPUT);
  pinMode(echoPin, INPUT);
  Serial.println("Hello Guys");

  connectToWiFi();
  mqttClient.setServer(mqttServer, mqttPort);
  mqttClient.setCallback(callback);
  connectToBroker();
}

void loop() {
  long duration, jarak;
  digitalWrite(triggerPin, LOW);
  delayMicroseconds(2);
  digitalWrite(triggerPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(triggerPin, LOW);
  duration = pulseIn(echoPin, HIGH);
  jarak = (duration / 2) / 29.1;
  Serial.print("jarak : ");
  Serial.print(jarak);
  Serial.println(" cm");

  char jarakString[8];
  dtostrf(jarak, 1, 1, jarakString);
  mqttClient.loop();  // Added for MQTT to work properly
  if (mqttClient.connected()) {
    mqttClient.publish(mqttTopic, jarakString);
  }

  delay(10);
}