#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27, 16, 2);
#define LDR 34      
#define TRIG 5       
#define ECHO 18       
#define RELAY 19      
#define G 4       

int LIGHT = 2000;     

void setup() {
  Serial.begin(9600);
  pinMode(TRIG, OUTPUT);
  pinMode(ECHO, INPUT);
  pinMode(RELAY, OUTPUT);
  pinMode(G, OUTPUT);
    lcd.init();
lcd.backlight();
  digitalWrite(RELAY, LOW); 
  digitalWrite(G, LOW); 
}

void loop() {
  int ldrValue = analogRead(LDR);     
  float distance = measureDistance(); 
  
  Serial.print("LDR Value: ");
  Serial.print(ldrValue);
  Serial.print(" Distance: ");
  Serial.println(distance);
  
  if (ldrValue > LIGHT) {
    
    digitalWrite(RELAY, LOW); 
    digitalWrite(G, LOW);
    lcd.setCursor(0,0);
    lcd.print("Bright");
    lcd.setCursor(0,1);
    lcd.print("Distance:");
    lcd.setCursor(8,1); 
    lcd.print(distance); 
  } else {
    
    if (distance <= 20) {
     
      digitalWrite(RELAY, HIGH); 
      digitalWrite(G, HIGH);
      lcd.setCursor(0,0);
      lcd.print("DARK  ");
      lcd.setCursor(0,1);
      lcd.print("Distance:");
      lcd.setCursor(8,1); 
      lcd.print(distance);  
    } else {
      digitalWrite(RELAY, LOW);  
      digitalWrite(G, LOW);
      lcd.setCursor(0,0);
      lcd.print("DARK  ");
      lcd.setCursor(0,1);
      lcd.print("Distance:");
      lcd.setCursor(8,1); 
      lcd.print(distance);   
    }
  }
  
  delay(500); 
}
float measureDistance() {
  digitalWrite(TRIG, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG, LOW);
  
  long duration = pulseIn(ECHO, HIGH);
  return (duration * 0.034) / 2;
}