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

const char* ssid = "Wokwi-GUEST";
const char* password = "";
const char* mqttServer = "thingsboard.cloud";
const int mqttPort = 1883; // MQTT default port
const char* token = "vgfet469d0rt7jme7boi";

const int triggerPin = 12;
const int echoPin = 14;

WiFiClient espClient;
PubSubClient client(espClient);

void setup() {
  Serial.begin(115200);
  pinMode(triggerPin, OUTPUT);
  pinMode(echoPin, INPUT);

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

  client.setServer(mqttServer, mqttPort);
}

void loop() {
  if (!client.connected()) {
    reconnect();
  }
  client.loop();

  long duration, distance;
  digitalWrite(triggerPin, LOW);
  delayMicroseconds(2);
  digitalWrite(triggerPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(triggerPin, LOW);
  duration = pulseIn(echoPin, HIGH);
  distance = duration * 0.034 / 2;

  sendDistanceToThingsboard(distance);
 
  delay(500); // Adjust delay as needed
}

void sendDistanceToThingsboard(long distance) {
  char jsonBuffer[100];
  snprintf(jsonBuffer, sizeof(jsonBuffer), "{\"distance\": %ld}", distance);

  Serial.print("Sending data to Thingsboard: ");
  Serial.println(jsonBuffer);

  if (client.publish("v1/devices/me/telemetry", jsonBuffer)) {
    Serial.println("Publish success");
  } else {
    Serial.println("Publish failed");
  }
}

void reconnect() {
  while (!client.connected()) {
    Serial.println("Attempting MQTT connection...");
    if (client.connect("ESP32Client", token, NULL)) {
      Serial.println("Connected to Thingsboard MQTT");
    } else {
      Serial.print("Failed, rc=");
      Serial.print(client.state());
      Serial.println(" Retrying in 5 seconds...");
      delay(5000);
    }
  }
}