#include <WiFi.h>
#include <PubSubClient.h>
int trigpin = 2;
int echopin = 4;

const char* hotspot = "Wokwi-GUEST";
const char* password = "";

const char* mqtt_broker = "broker.emqx.io";
const char* topic = "akucintamyungjae";
const int mqtt_port = 1883;
String client_id = "mqttx_771550GHJJJJ76";

WiFiClient espClient;
PubSubClient client (espClient);

int waktu_sebelum, waktu_interval = 1*1000;

float distance, duration;

void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  pinMode(trigpin, OUTPUT);
  pinMode(echopin, INPUT);

  WiFi.begin(hotspot, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.println("Menghubungkan ke WiFi..");
  }
  Serial.println("Sudah terhubung");

  client.setServer(mqtt_broker, mqtt_port);
  while (!client.connected()) {
    if (client.connect(client_id.c_str())) {
      Serial.println("Terhubung ke mqtt broker");
    } else {
      Serial.print("Gagal terhubung ");
      Serial.print(client.state());
      delay(2000);
    }
  }
}

void loop() {
  digitalWrite(trigpin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigpin, LOW);

  duration = pulseIn(echopin, HIGH);

  distance = 0.017*duration;

  Serial.println(distance);
  delay(1000);


  client.loop();
  if (millis() - waktu_sebelum >= waktu_interval){
    client.publish(topic, String(distance).c_str());
    waktu_sebelum = millis();
  }
}