#define ADC_IN A5
#define ADC_REF 3.3
#define Buzzer 4
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27, 16, 2);

#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 = "PROJECT_JYQ";
int PORTNUM = 1883;

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) ) 
    {
     Serial.println("Connected");
     MQTTSubscribe();
    }
   else
    {
     Serial.print("Failed with state ");
     Serial.print(client.state() );
     delay(2000);
    }
  }
}

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

void MQTTSubscribe()
{
 client.subscribe("JCE/IoT");
}

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];
  }
}

void setup() 
{
 lcd.init();
 lcd.backlight();
 lcd.setCursor(2,0);
 lcd.print("Hi");
 lcd.setCursor(0,1);
 lcd.print("Welcome :)");
 delay(400);
 lcd.clear();

 Serial.begin(115200);
 pinMode(23, OUTPUT);
 pinMode(18, OUTPUT);
 pinMode(Buzzer, OUTPUT);

 setup_wifi();
 setup_MQTT();
}

void loop()
{

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

int adcRes = analogRead( ADC_IN );
delay(10);
float voltage = (float) adcRes * ADC_REF/4095;
Serial.println( adcRes );  
String payload = String(adcRes);
client.publish("JCE/IoT",payload.c_str()); 
if (analogRead(ADC_IN) <= 2047) //0 to 50
  {
    digitalWrite(23, HIGH); 
    digitalWrite(18, LOW);

    lcd.clear();
    lcd.setCursor(5,0);
    lcd.print("Hello!");
    lcd.setCursor(1,1);
    lcd.print("Smart human :)");
    delay(1000);
  }
  else
  {
    digitalWrite(23, LOW);
    digitalWrite(18, HIGH);
  }
if (analogRead(ADC_IN) > 2047)
if (analogRead(ADC_IN) <= 4095)//50 to 100
  {
  digitalWrite(23, LOW);
  digitalWrite(18, HIGH);

    lcd.clear();
    lcd.setCursor(1,0);
    lcd.print("Bin is too hot!");
    lcd.setCursor(5,1);
    lcd.print("Ah!!!!");
    delay(1000);

    digitalWrite(Buzzer, HIGH);
    delay(1000);
    digitalWrite(Buzzer, LOW);
    client.publish("JCE/IoT","Bin is too hot!");
  }
else
  {
  digitalWrite(23, HIGH);
  digitalWrite(18, LOW);
  }
}