#include <DHT.h>
#include <LiquidCrystal.h>

// Define pins for DHT22
#define DHTPIN 2
#define DHTTYPE DHT22

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

// Initialize the LCD
LiquidCrystal lcd(7, 6, 5, 4, 3, 2);

// Define LED pins
const int redLedPin = 10;
const int greenLedPin = 11;
const int blueLedPin = 12;

// Define potentiometer pin
const int contrastPin = A0;  // Connect potentiometer middle pin to A0

void setup() {
  // Start serial communication
  Serial.begin(9600);

  // Initialize the LCD
  lcd.begin(16, 2);

  // Initialize DHT22 sensor
  dht.begin();

  // Set LED pins as outputs
  pinMode(redLedPin, OUTPUT);
  pinMode(greenLedPin, OUTPUT);
  pinMode(blueLedPin, OUTPUT);

  // Set contrast pin (V0) as input
  pinMode(contrastPin, INPUT);
}

void loop() {
  // Read temperature as Celsius
  float temperature = dht.readTemperature();

  // Check if any reads failed
  if (isnan(temperature)) {
    lcd.clear();
    lcd.print("Error reading");
    lcd.setCursor(1, 0);
    lcd.print("DHT sensor");
    return;
  }

  // Display temperature on LCD

  lcd.clear();
  lcd.begin(16, 2);
  lcd.setCursor(1,0);
  lcd.print("Temp: ");
  lcd.print(temperature);
  lcd.print(" C");

  // Read potentiometer value for LCD contrast adjustment
  int contrastValue = analogRead(contrastPin);

  // Adjust LCD contrast based on potentiometer value
  lcd.setCursor(2, 1);  // Set cursor to the second line
  lcd.print("Contrast: ");
  lcd.print(contrastValue);  // Display potentiometer value

  // Control LEDs based on temperature range
  if (temperature > 30) {
    digitalWrite(redLedPin, HIGH);
    digitalWrite(greenLedPin, LOW);
    digitalWrite(blueLedPin, LOW);
  } else if (temperature >= 20 && temperature <= 30) {
    digitalWrite(redLedPin, LOW);
    digitalWrite(greenLedPin, HIGH);
    digitalWrite(blueLedPin, LOW);
  } else {
    digitalWrite(redLedPin, LOW);
    digitalWrite(greenLedPin, LOW);
    digitalWrite(blueLedPin, HIGH);
  }

  // Wait a few seconds between measurements
  delay(2000);
}