#include <ESP32Servo.h>  // Include library to control servos on ESP32

    Servo servo;  // Create a Servo object

    // Servo settings
    int servoPos = 90;                 // Start position (middle)
    const int servoLimitHigh = 180;    // Max servo angle
    const int servoLimitLow  = 0;      // Min servo angle
    const int servoPin = 10;           // PWM pin connected to servo

    // LDR (photoresistor) pins
    const int ldrNorth = A0;           // North sensor
    const int ldrSouth = A1;           // South sensor

    // Servo movement tolerance
    const int tolerance = 150;         // Minimum difference between sensors to move servo

    void setup() {
    Serial.begin(115200);           // Initialize serial monitor for debugging
    servo.attach(servoPin);         // Attach servo to the PWM pin
    servo.write(servoPos);          // Move servo to initial position
    delay(1000);                    // Wait 1 second for servo to reach position
    }

    void loop() {
    // Read analog values from LDRs (0–4095 on ESP32)
    int northValue = analogRead(ldrNorth);
    int southValue = analogRead(ldrSouth);

    // Calculate difference between sensors
    int difference = northValue - southValue;

    // Print readings for debugging
    Serial.print("North ADC: "); Serial.print(northValue);
    Serial.print("  South ADC: "); Serial.print(southValue);
    Serial.print("  Difference: "); Serial.println(difference);

    // Only move servo if the difference is larger than tolerance
    if (abs(difference) > tolerance) {
        // Map the difference to a step size (1–5 degrees)
        // Bigger difference → bigger movement
        int stepSize = map(abs(difference), tolerance, 4095, 1, 5);

        // Move servo left or right depending on which LDR is brighter
        if (difference > 0) servoPos += stepSize; // North is brighter → move right
        else servoPos -= stepSize;                // South is brighter → move left

        // Keep servo angle within limits
        servoPos = constrain(servoPos, servoLimitLow, servoLimitHigh);

        // Update servo position
        servo.write(servoPos);
    }

    delay(50);  // Small delay to reduce jitter and avoid moving too fast
    }