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

// WiFi sozlamalari
const char* ssid = "Wokwi-GUEST";
const char* password = "";
const char* mqtt_server = "broker.hivemq.com";

// Pinlar
#define TRIG_PIN 5
#define ECHO_PIN 18

WiFiClient espClient;
PubSubClient client(espClient);

void setup_wifi() {
  Serial.print("WiFiga ulanmoqda...");
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("WiFiga ulandi!");
}

void reconnect() {
  while (!client.connected()) {
    Serial.print("MQTT brokerga ulanmoqda...");
    String clientId = "ESP32Client-" + String(random(0xffff), HEX);
    if (client.connect(clientId.c_str())) {
      Serial.println("MQTT brokerga ulandi!");
    } else {
      Serial.print("Xatolik: ");
      Serial.println(client.state());
      delay(2000);
    }
  }
}

void setup() {
  Serial.begin(115200);
  pinMode(TRIG_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);
  setup_wifi();
  client.setServer(mqtt_server, 1883);
}

long getDistanceCM() {
  digitalWrite(TRIG_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);

  long duration = pulseIn(ECHO_PIN, HIGH);
  long distance = duration * 0.034 / 2; // sm ga aylantirish
  return distance;
}

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

  long distance = getDistanceCM();
  Serial.print("O‘lchangan masofa: ");
  Serial.print(distance);
  Serial.println(" sm");

  String msg = "Yuborildi -> Qiymat – " + String(distance) + "sm";
  client.publish("esp32/hcsr04", msg.c_str());
  Serial.println(msg);

  delay(3000); // 3 soniyada bir o‘lchash
}