#include <WiFi.h>
#include <PubSubClient.h>
#include <LiquidCrystal_I2C.h>
const char * MQTTServer = "broker.emqx.io"; 
const char * MQTT_lcd = "VLUTE/LCD1"; 
const char * MQTT_ID = "6348165a-ab20-4761-9e7c-2fb284383a16";
  
WiFiClient espClient;
PubSubClient client(espClient);

int lcdColumns = 20;
int lcdRows = 4;
LiquidCrystal_I2C lcd(0x27, lcdColumns, lcdRows);  
void WIFIConnect() {
  Serial.println("Connecting to SSID: Wokwi-GUEST");
  WiFi.begin("Wokwi-GUEST", "");
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("");
  Serial.print("WiFi connected");
  Serial.print(", IP address: ");
  Serial.println(WiFi.localIP());
}
void MQTT_Reconnect() {
  while (!client.connected()) {
    if (client.connect(MQTT_ID)) {
      Serial.print("MQTT lcd: ");
      Serial.print(MQTT_lcd);
      Serial.print(" connected");
      client.subscribe(MQTT_lcd);
      Serial.println("");
    } else {
      Serial.print("failed, rc=");
      Serial.print(client.state());
      Serial.println(" try again in 5 seconds");
      delay(5000);
    }
  }
}
void callback(char* topic, byte* message, unsigned int length) {
  Serial.print("Message arrived on topic: ");
  Serial.println(topic);
  Serial.print("Message: ");
  String stMessage;

  for (int i = 0; i < length; i++) {
    Serial.print((char)message[i]);
    stMessage += (char)message[i];
  }
  lcd.setCursor(0, 0);
  lcd.print(stMessage);
  delay(1000);
}

void setup() {
  Serial.begin(115200);     
  WIFIConnect();                           
  lcd.init();                  
  lcd.backlight();
  client.setServer(MQTTServer, 1883); 
  client.setCallback(callback);

}
void loop() { 
  delay(10);
  if (!client.connected()) {
    MQTT_Reconnect();
  }
  client.loop();
}