#include <LiquidCrystal_I2C.h>
#include <ESP32Servo.h>
#define LDR_PIN 13

// LDR Characteristics
const float GAMMA = 0.7;
const float RL10 = 50;
LiquidCrystal_I2C lcd(0x27, 16, 2);
Servo myservo;

void setup() {
  // put your setup code here, to run once:
  
  pinMode(LDR_PIN, INPUT);
  lcd.init();
  lcd.backlight();
  myservo.attach(23);
  
}
int i = 0;
void loop() {
  int analogValue = analogRead(LDR_PIN);
  float voltage = analogValue / 4096. * 5;
  float resistance = 2000 * voltage / (1 - voltage / 5);
  float lux = pow(RL10 * 1e3 * pow(10, GAMMA) / resistance, (1 / GAMMA));
  lcd.setCursor(0,1);
  lcd.print(lux);
  delay(100);

  if(lux>5000){
    for(i = 0; i<=180; i++){
      myservo.write(i);
      delay(15);
    }
    for(i = 180; i>=0; i--){
      myservo.write(i);
      delay(15);
    }
    
  } 
  
}