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

#define PIR_PIN 25
#define LED_PIN 23
#define NTC_PIN 34
#define LCD_PIN 21
#define I2C_ADDR 0x27
#define LCD_COLUMNS 20
#define LCD_LINES 4

LiquidCrystal_I2C LCD(0x27, 20, 4); // Adjust address if necessary

void setup() {
  pinMode(PIR_PIN, INPUT);
  pinMode(LED_PIN, OUTPUT);
LCD.begin(20,4);
LCD.backlight();
}

void loop() {
  int motionDetected = digitalRead(PIR_PIN);

  if (motionDetected == HIGH) {
    float temperature = readTemperature();
    LCD.setCursor(0, 0);
    LCD.print("Temp: ");
    LCD.print(temperature);
    LCD.print(" C");

    if (temperature < 10) {
      digitalWrite(LED_PIN, HIGH);
      LCD.setCursor(0, 1);
      LCD.print("LED On        ");
    }
    
    delay(5000); // Wait for 5 seconds for the PIR sensor to reset
  } else {
    digitalWrite(LED_PIN, LOW);
    LCD.clear();
  }
}

float readTemperature() {
  int rawValue = analogRead(NTC_PIN);
  float voltage = (rawValue / 4095.0) * 3.3; // Assuming 3.3V reference
  float resistance = (3.3 / voltage) - 1; // Calculate the resistance of the NTC
  float temperature = 1.0 / (0.001129148 + 0.000234125 * log(resistance) + 0.0000000876741 * log(resistance) * log(resistance) * log(resistance)); // Steinhart-Hart equation
  return temperature - 273.15; // Convert from Kelvin to Celsius
}