#include <DHT.h>
#include <LiquidCrystal_I2C.h>
#define DHTPIN 11     
#define DHTTYPE DHT22
#include <Keypad.h>

const byte ROWS = 4; 
const byte COLS = 4; 
boolean R=false;

char hexaKeys[ROWS][COLS] = {
  {'1', '2', '3', 'A'},
  {'4', '5', '6', 'B'},
  {'7', '8', '9', 'C'},
  {'*', '0', '#', 'D'}
};

byte rowPins[ROWS] = {9, 8, 7, 6}; 
byte colPins[COLS] = {5, 4, 3, 2}; 

Keypad customKeypad = Keypad(makeKeymap(hexaKeys), rowPins, colPins, ROWS, COLS); 

int lightvalue=0;
LiquidCrystal_I2C lcd(0x27,16,2); 
DHT dht(DHTPIN, DHTTYPE);

void setup() {
  dht.begin();
  Serial.begin(9600);
  lcd.init(); 
  lcd.backlight();
  lcd.clear();                 
  lcd.setCursor(5, 0);         
  lcd.print("Arduino");        
  lcd.setCursor(3, 1);         
  lcd.print("Smart Home"); 
  delay(2000);  
  pinMode(12,OUTPUT);
  pinMode(13,OUTPUT);  
  digitalWrite(12,LOW);             
}

void loop() {
  int temperature = dht.readTemperature();
  int humidity = dht.readHumidity();

  if (isnan(temperature) || isnan(humidity)) {
    Serial.println(("Failed to read from DHT sensor!"));
    return;
  }
  lightvalue=analogRead(A0);
  lightvalue=map(lightvalue,1023,0,0,100);

  char customKey = customKeypad.getKey();
  
// toggle relay to turn on/off light using relay when 5 is pressed
  if(customKey == '5' && R==false)
  {
    digitalWrite(12,HIGH);
    R=true;
  }
  else if (customKey == '5' && R==true)
  {
    digitalWrite(12,LOW);
    R=false;
  }
//if temperature high on the relay for fan
  if (temperature >30)
  digitalWrite(13,HIGH);
  else 
  digitalWrite(13,LOW);
  delay(200);                 
  
  lcd.clear();                  
  lcd.setCursor(0, 0);         
  lcd.print("T:"); 
  lcd.print(temperature);
  lcd.print("C  ");
  lcd.print("Hum.:"); 
  lcd.print(humidity);
  lcd.print("%");
  lcd.setCursor(0, 1); 
  lcd.print("Brightness:");
  lcd.print(lightvalue);
  lcd.print("%");
  delay(100);
}