#include <ESP32WiFi.h>
#include <PubSubClient.h>

int Relay = D1;
const char *ssid = "KMITL_WiFi";
const char *password = "";

const char *mqtt_broker = "broker.hivemq.com";
const char *topic = "temp";
const int mqtt_port =1883;
WiFiClient espClient;
PubSubClient client(espClient);

void setup() {
  Serial.begin(115200);
  pinMode(Relay, OUTPUT);
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.println("Connecting to WiFi..");
  }

  Serial.println("Connected");

  client.setServer(mqtt_broker, mqtt_port);
  client.setCallback(callback);

  while(!client.connected()) {
    String client_id = "esp32-client-";
    client_id += String(WiFi.macAddress());

    Serial.printf("The clint %s connects to mosquitto mqtt broker\n", client_id.c_str());

    if (client.connect(client_id.c_str())){
      Serial.println("Public emqx mqtt broker connected");
    }else {
      Serial.print("failed with state ");
      Serial.print(client.state());
      delay(2000);
    }
  }
}