#include <DHT.h> // Include the DHT sensor library
#include <LiquidCrystal.h> // Include the LiquidCrystal library for LCD

#define DHTPIN 10 // Define the pin for the DHT sensor
#define DHTTYPE DHT22 // Define the type of DHT sensor

#define LCD_RS 12 // Define the LCD RS pin
#define LCD_EN 11 // Define the LCD EN pin
#define LCD_D4 5 // Define the LCD D4 pin
#define LCD_D5 4 // Define the LCD D5 pin
#define LCD_D6 3 // Define the LCD D6 pin
#define LCD_D7 2 // Define the LCD D7 pin

#define BUZZER_PIN 8 // Define the buzzer pin
#define SNOOZE_BUTTON_PIN 7 // Define the snooze button pin
#define BACKLIGHT_BUTTON_PIN 6 // Define the backlight button pin
#define BACKLIGHT_PIN 9 // Define the backlight pin

DHT dht(DHTPIN, DHTTYPE); // Create a DHT object
LiquidCrystal lcd(LCD_RS, LCD_EN, LCD_D4, LCD_D5, LCD_D6, LCD_D7); // Create an LCD object


void setup() {
  dht.begin(); // Initialize DHT sensor
  lcd.begin(16, 2); // Initialize LCD with 16 columns and 2 rows
  pinMode(BUZZER_PIN, OUTPUT); // Set buzzer pin as output
  pinMode(SNOOZE_BUTTON_PIN, INPUT_PULLUP); // Set snooze button pin as input with internal pull-up resistor
  pinMode(BACKLIGHT_BUTTON_PIN, INPUT_PULLUP); // Set backlight button pin as input with internal pull-up resistor
  pinMode(BACKLIGHT_PIN, OUTPUT); // Set backlight pin as output
}

void loop() {
  float temperature = dht.readTemperature(); // Read temperature from DHT sensor
  float humidity = dht.readHumidity(); // Read humidity from DHT sensor

  // Check if temperature or humidity reading is invalid
  if (isnan(temperature) || isnan(humidity)) {
    lcd.print("Error reading data"); // Print error message on LCD
    return; // Exit loop
  }

  digitalWrite(9, HIGH);
  lcd.clear(); // Clear LCD screen
  lcd.setCursor(0, 0); // Set cursor to the first column of the first row
  lcd.print("Temp: "); // Print temperature label
  lcd.print(temperature); // Print temperature value
  lcd.print("C"); // Print temperature unit
  lcd.setCursor(0, 1); // Set cursor to the first column of the second row
  lcd.print("Humidity: "); // Print humidity label
  lcd.print(humidity); // Print humidity value
  lcd.print("%"); // Print humidity unit
  delay(5000);

  // Check if temperature or humidity is above threshold
  if (temperature > 30 || humidity > 15) {
      digitalWrite(BUZZER_PIN, HIGH); // Turn on the buzzer
      tone(BUZZER_PIN, 300, 1000); // Plays 300Hz tone for 1 seconds
      delay(1000);
      digitalWrite(BUZZER_PIN, LOW);  // Turn off the buzzer
      delay(1000);  

      if (digitalRead(SNOOZE_BUTTON_PIN) == LOW) {
        delay(10000);// Snooze for 10 seconds
        tone(BUZZER_PIN, 300, 1000); // Plays 300Hz tone for 1 seconds
        delay(1000);
        digitalWrite(BUZZER_PIN, LOW); // Turn off the buzzer
      }     
  }
  
digitalWrite(9, LOW);
delay(5000);//Assuming that the user press the Backlight button after 5 seconds

if (digitalRead(BACKLIGHT_BUTTON_PIN) == LOW){
  digitalWrite(9, HIGH);
  delay(2000); //To visualize the backlight turning on
}

delay(1000); // Sampling rate of 1 second
}