#include <LiquidCrystal_I2C.h>

/* Arduino example code for DHT11, DHT22/AM2302 and DHT21/AM2301 temperature and humidity sensors. More info: www.www.makerguides.com */

// Include the libraries:
#include <Adafruit_Sensor.h>
#include <DHT.h>
#include <Wire.h> 
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27, 16, 2); // I2C address 0x27, 16 column and 2 rows

// Set DHT pin:
#define DHTPIN 12

// Set DHT type, uncomment whatever type you're using!
//#define DHTTYPE DHT11   // DHT 11 
#define DHTTYPE DHT22   // DHT 22  (AM2302)
//#define DHTTYPE DHT21   // DHT 21 (AM2301)

// Initialize DHT sensor for normal 16mhz Arduino:
DHT dht = DHT(DHTPIN, DHTTYPE);

float Humback[30];
float Tempback[30];
int cycles = 0;

byte ArrowUp[8] = {
  B00100,
  B01110,
  B10101,
  B00100,
  B00100,
  B00100,
  B00100,
};
byte ArrowDown[8] = {
  B00100,
  B00100,
  B00100,
  B00100,
  B10101,
  B01110,
  B00100,
};
void setup() {
  // Setup sensor:
  dht.begin();
  lcd.init(); // initialize the lcd
  lcd.backlight();
  lcd.clear();
  lcd.createChar(0, ArrowUp);
  lcd.createChar(1, ArrowDown);
}

void loop() {


  // Read the humidity in %:
  float h = dht.readHumidity();
  // Read the temperature as Celsius:
  float t = dht.readTemperature();

  // Check if any reads failed and exit early (to try again):
  if (isnan(h) || isnan(t)) {
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("Failed to read from DHT sensor!");
    return;
  }

  // Compute heat index in Celsius:
  float hic = dht.computeHeatIndex(t, h, false);
  Tempback[cycles] = t;
  Humback[cycles] = h;
  cycles ++;
  if (cycles == 30)
  {
    cycles = 0;
    lcd.clear();
  }



  if (t >= 45)
  {
    lcd.clear();
    lcd.setCursor(4, 0);
    lcd.print("TOO HOT!!");
    delay(1000);
    lcd.clear();
  }
  
  //lcd.clear();
  lcd.setCursor(2, 0);
  lcd.print("Hum: ");
  lcd.print(h);
  lcd.print("%");
    if (h > Humback[cycles+1])
  {
    lcd.write(byte(0));
  }
  else if (h < Humback[cycles+1])
  {
    lcd.write(byte(1));
  }
  else
  {
    lcd.print(" ");
  }

  lcd.setCursor(1, 1);
  lcd.print("Temp: ");
  lcd.print(t);
  lcd.print("C");
  if (t > Tempback[cycles+1])
  {
    lcd.write(byte(0));
  }
  else if (t < Tempback[cycles+1])
  {
    lcd.write(byte(1));
  }
  else
  {
    lcd.print(" ");
  }
  
  // Wait a few seconds between measurements:
  delay(2000);

}