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

const char* ssid = "Wokwi-GUEST";
const char* password = "";

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



WiFiClient espClient;
PubSubClient client(espClient);
const char* espClientName = "stanleyyeo9165"; // yourStudentID must be unique
int PORTNUM = 1883;

int ledPin = 23;
int ledPin2 = 18;

long previousMillis = 0;
long interval = 1000;
int state = 0;


long previousMillis2 = 0;
long interval2 = 500;
int state2 = 0;

long previousMillisY = 0;
long intervalY = 500;

long previousMillisA = 0;
long intervalA = 500;

void setup_wifi()
{
  WiFi.begin(ssid, password);
  while(WiFi.status() != WL_CONNECTED )
  {
    delay(1000);
    Serial.print(".");
  }
  Serial.println();
  Serial.print("Connected to ");
  Serial.println(ssid);
  Serial.print("Given IP by the router to ESP32 is ");
  Serial.println(WiFi.localIP());
}


void connectMQTT()
{
  while(!client.connected() )
  {
    Serial.println("Connecting to MQTT ...");
    if (client.connect(espClientName) ) //, mqttUser, mqttPassword) )
    {
      Serial.println("Connected");
      MQTTSubscribe();
    }
    else
    {
      Serial.print("Failed with state ");
      Serial.print(client.state() );
      delay(2000);
    }
  }
}

void callback(String topic, byte* payload, unsigned int length)
{
  String messageTemp;
  Serial.print("Message received in topic: ");
  Serial.print(topic);
  Serial.print(" length is: ");
  Serial.println(length);

  Serial.print("Data received from broker: ");
  for (int i = 0; i<length; i++)
  {
    Serial.print( (char)payload[i] );
    messageTemp += (char)payload[i];
  }

/// Handle your topics and payload here
// Example

  if (topic == "LT51G/9024973R/LED")
  {
    Serial.print("Changing room LED to ");
    if (messageTemp == "Off")
    {
      digitalWrite(18, HIGH);
      Serial.print("Off");
    }
    else if (messageTemp == "On")
    {
      digitalWrite(18, LOW);
      Serial.print("On");
    }
  }
}

void MQTTSubscribe() 
{
  // Subsccribe to your topics here
  client.subscribe("LT51G/9024973R/LED");  

}

void setup_MQTT() 
{
  client.setServer(hostname, PORTNUM);
  client.setCallback(callback); 
}

void setup() 
{
  
  Serial.begin(115200);
  Serial.println("Hello, ESP32!");

  pinMode(23, OUTPUT);
  pinMode(18, OUTPUT);

   setup_wifi();
   setup_MQTT();
}

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

  //client.publish("LT51G/9024973R/LED","On");
//delay(1000);
//client.publish("LT51G/9024973R/LED","OFF");
//delay(1000);


 long currentMillis = millis();
 
 if (currentMillis - previousMillis >= interval)
 {
  previousMillis = currentMillis;

  if (digitalRead(ledPin) == HIGH)
  {
    digitalWrite(ledPin, LOW);
  }
   else
    {
      digitalWrite(ledPin, HIGH);
    }
  }

long currentMillis2 = millis();
 if (currentMillis2 - previousMillis2 >= interval2)
 {
  previousMillis2 = currentMillis2;

if (state2 == 0)
{
  state2 = 1;
  client.publish("LT51G/9024973R/LED/yourLT/LED","on");
}
else
{state2 = 0;
client.publish("LT51G/9024973R/LED/yourLT/LED","off");
}
  
 
  }
}