#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include <DHT.h>

// Define pins
#define DHTPIN 2     // DHT sensor pin
#define RELAY_PIN1 5 // Relay pin for heater/fan
#define BUTTON_PIN1 3 // Push button1 pin
#define BUTTON_PIN2 4 // Push button2 pin

// Define the pins
#define DHTTYPE DHT22 // DHT 22 (AM2302)

float currentTemp = 0.0;
float desiredTemp = 35.0; // Default desired temperature
float currentHumidity = 0.0;
float desiredHumidity = 60.0; // Fixed typo

// Initialize the DHT sensor
DHT dht(DHTPIN, DHTTYPE);

// Initialize the LCD (address 0x27, 20 columns and 4 rows)
LiquidCrystal_I2C lcd(0x27, 20, 4);
bool relayState = false;

void setup() {
  lcd.init();
  lcd.backlight();
  dht.begin();
  
  pinMode(13, OUTPUT);
  pinMode(RELAY_PIN1, OUTPUT);
  pinMode(BUTTON_PIN1, INPUT_PULLUP); // Use internal pull-up resistor
  pinMode(BUTTON_PIN2, INPUT_PULLUP); // Use internal pull-up resistor

  lcd.setCursor(4, 0);
  lcd.print("PV");
  lcd.setCursor(12, 0);
  lcd.print("SV");
}

void loop() {
  // Read current temperature and humidity
  currentTemp = dht.readTemperature();
  currentHumidity = dht.readHumidity();
  
  // Check if the button is pressed
  if (digitalRead(BUTTON_PIN1) == LOW) {
    delay(50); // Debounce delay
    blinkLCD(6); // Blink the LCD for 5 times
    lcd.backlight();
  }
  
  if (digitalRead(BUTTON_PIN2) == LOW) {
    delay(50); // Debounce delay
    desiredTemp += 0.1; // Increase desired temperature by 0.1°C
    if (desiredTemp > 50.0) { // Limit to 50°C if it exceeds 50°C
      desiredTemp = 50.0;
    }
  }

  // Control the relay based on current temperature
  if (currentTemp < desiredTemp) {
    digitalWrite(RELAY_PIN1, HIGH); // Turn on heater/fan
    relayState = true;
    digitalWrite(13, HIGH);
  } else {
    digitalWrite(RELAY_PIN1, LOW); // Turn off heater/fan
    relayState = false;
    digitalWrite(13, LOW);
  }

  // Display the temperature and humidity on the LCD
  lcd.setCursor(0, 1);
  lcd.print("T: ");
  lcd.print(currentTemp);
  lcd.setCursor(17, 1);
  lcd.print("'C");

  lcd.setCursor(0, 2);
  lcd.print("H: ");
  lcd.print(currentHumidity);
  lcd.setCursor(17, 2);
  lcd.print(" %");

  lcd.setCursor(11, 1);
  lcd.print(desiredTemp);
  
  lcd.setCursor(11, 2);
  lcd.print(desiredHumidity);
  
  delay(200); // Update every second
}

// Function to blink the LCD
void blinkLCD(int times) {
  for (int i = 0; i < times; i++) {
    lcd.backlight(); // Turn on backlight
    delay(500);      // Wait for 500 ms
    lcd.noBacklight(); // Turn off backlight
    delay(500);      // Wait for 500 ms
  }
}