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

// Define DHT sensor type and pin
#define DHTTYPE DHT11
#define DHTPIN 2
DHT dht(DHTPIN, DHTTYPE);

// Initialize LCD (16x2)
LiquidCrystal_I2C lcd(0x27, 16, 2);

// Define Ultrasonic Sensor pins
#define TRIG_PIN 3
#define ECHO_PIN 4

// Piezoelectric Gauge Pin
#define PIEZO_PIN A0

// LED and Buzzer Pins
#define LED_PIN 9
#define BUZZER_PIN 8

void setup() {
  // Initialize LCD and sensors
  lcd.begin(16, 2);
  lcd.backlight();
  dht.begin();
  pinMode(TRIG_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);
  pinMode(LED_PIN, OUTPUT);
  pinMode(BUZZER_PIN, OUTPUT);
  
  lcd.setCursor(0, 0);
  lcd.print("Interactive Learn");
}

void loop() {
  // Ultrasonic Sensor for Motion Detection
  long duration;
  digitalWrite(TRIG_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);
  duration = pulseIn(ECHO_PIN, HIGH);
  long distance = duration * 0.034 / 2;
  
  if (distance < 50) {  // Detect user presence
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("Weather Info");
    lcd.setCursor(0, 1);
    lcd.print("Press Button");
    
    // Display Weather Data
    float temp = dht.readTemperature();
    float hum = dht.readHumidity();
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("Temp: " + String(temp) + "C");
    lcd.setCursor(0, 1);
    lcd.print("Humidity: " + String(hum) + "%");
    delay(2000);
  }
  
  // Piezoelectric Voltage
  int piezoVoltage = analogRead(PIEZO_PIN);
  if (piezoVoltage > 10) {
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("Energy: ");
    lcd.setCursor(0, 1);
    lcd.print(String(piezoVoltage) + " mV");
    digitalWrite(LED_PIN, HIGH);
    delay(500);
    digitalWrite(LED_PIN, LOW);
  }
  
  delay(100);
}