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

// Wi-Fi credentials
const char* ssid = "Wokwi-GUEST";
const char* password = "";

const char* mqtt_server = "broker.hivemq.com";

WiFiClient espClient;
PubSubClient client(espClient);

// Callback jab message aayega
void callback(char* topic, byte* message, unsigned int length) {
  Serial.print("Message arrived on topic: ");
  Serial.println(topic);

  Serial.print("Message: ");
  for (int i = 0; i < length; i++) {
    Serial.print((char)message[i]);
  }
  Serial.println("\n------------------------");
}

void setup_wifi() {
  delay(10);
  Serial.println("Connecting to WiFi...");
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("\nWiFi connected");
  Serial.println("IP address: ");
  Serial.println(WiFi.localIP());
}

void reconnect() {
  while (!client.connected()) {
    Serial.print("Connecting to MQTT...");
    if (client.connect("ESP32-Subscriber")) {
      Serial.println("connected");
      client.subscribe("sahil123/temperature");
    } else {
      Serial.print("failed, rc=");
      Serial.print(client.state());
      delay(2000);
    }
  }
}

void setup() {
  Serial.begin(115200);
  setup_wifi();
  client.setServer(mqtt_server, 1883);
  client.setCallback(callback);
}

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