#include <Arduino.h>
// Define pin numbers
const int LDR_Pin = 2; // LDR sensor connected to analog pin A0
const int GREEN_LED = 22; // Green LED connected to digital pin 13
const int RED_LED = 21; // Red LED connected to digital pin 12

// Define thresholds for LED indicators
const int GREEN_Threshold = 600; // Example threshold for green LED
const int RED_Threshold = 800; // Example threshold for red LED

float analogToLux(int analogValue) {

  float resistance = 10000.0 / ((1023.0 / analogValue) - 1.0); // 10kΩ resistor used
  float lux = map(resistance, 10000, 1000000, 100, 0); // Map resistance range to Lux range
  return lux;
}

void setup() {
  // Initialize serial communication
  Serial.begin(9600);
  pinMode(LDR_Pin , INPUT);
  pinMode(GREEN_LED, OUTPUT);
  pinMode(RED_LED, OUTPUT);
}

void loop() {
  // Read analog value from LDR sensor
  int ldrValue = analogRead(LDR_Pin);
  float lux = analogToLux(ldrValue);
  
  // Display the measured light intensity value on the serial monitor
  Serial.print("Light Intensity: ");
  Serial.println(ldrValue);

  Serial.print("Light Intensity (Lux): ");
  Serial.println(lux);

  // Turn on/off LED indicators based on light intensity thresholds
  if (ldrValue > GREEN_Threshold) {
    digitalWrite(GREEN_LED, HIGH);
    digitalWrite(RED_LED, LOW);
  } else if (ldrValue < RED_Threshold) {
    digitalWrite(GREEN_LED, LOW);
    digitalWrite(RED_LED, HIGH);
  } else {
    digitalWrite(GREEN_LED, LOW);
    digitalWrite(RED_LED, LOW);
  }
  delay(1000); 
}