#include "WiFi.h"
#include "PubSubClient.h"

int led_pin = 5;
char clientId[50];

WiFiClient espClient;
PubSubClient client(espClient);

void setup() 
{

  Serial.begin(115200);
  pinMode(led_pin, OUTPUT);

  WiFi.mode(WIFI_SIA);
  WiFi.begin("Wokwi-GUEST", "");

  client.setServer("broker.emqx.io", 1883);
  client.setCallback(callback);

}


void mqttReconnect() 
{

  while (!client.connected())
  {

    Serial.print("Attempting MQTT connection....");
    if (client.connect(clientId))
    {

      Serial.println(("Connected"));
      client.subscribe("topicName");

    }
    else
    {

      Serial.print("Connection failed try again in 5 seconds");
      delay(5000);

    }

  }

}

void callback(char* topic, byte* message, unsigned int length) 
{
  String stMessage;
  for (int i = 0; i < length; i++) 
  {
    stMessage += (char)message[i];
  }
  if (stMessage == "off")
    {

      digitalWrite((led_pin, LOW));
      Serial.print(("LIGHT OFF!"));

    }
  else if (stMessage == "off")
  {

    digitalWrite((led_pin, HIGH));
    Serial.print(("LIGHT ON✨"));
  }
  else
  {

    Serial.print("INVALID COMMAND❌")

  }
}

void loop() 
{

  delay(10000)
  if (!client.connected())
  {

    mqttReconnect();

  }
  client.loop();

}