#include "WiFi.h"
#include "PubSubClient.h"
#include <SevSeg.h>
// Import Seven segment library

char clientId[500];
int t;
// Declare date variable

// Configure Seven segment
SevSeg sevseg;
WiFiClient espClient;
PubSubClient client(espClient);
 
void setup() 
{
  Serial.begin(115200);

  // Declare pins
  byte num_digits=4;
  byte d_pins[] = {14, 15, 2, 5};
  byte s_pins[] = {12, 4, 19, 26, 27, 13, 18, 25};
  byte hardwareConfig = COMMON_ANODE;
  // Initiate Seven segment
  sevseg.begin(hardwareConfig, num_digits, d_pins, s_pins);

  WiFi.mode(WIFI_STA);
  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/time");
    } 
    else 
    {
      Serial.println("Connection failed trying 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];
  }
  // Print date
  Serial.println(stMessage);
  // Convert date format into number
  t=stMessage.toInt();
}
void loop() 
{
  if (!client.connected()) 
  {
    mqttReconnect();
  }
  client.loop();

  // Set the number
  sevseg.setNumber(t);
  // Display the number
  sevseg.refreshDisplay();
  // delay() function
  delay(1);
}