#include <Stepper.h>
#include <Servo.h>

// Define the number of steps per revolution for your stepper motor
const int stepsPerRevolution = 200;

// Create a Stepper object
Stepper myStepper(stepsPerRevolution, 8, 9, 10, 11);

// Define servo and LED pin
const int servoPin = 17; // Change to your servo pin number
const int trayPresentLED = 2; // Change to your LED pin number
const int ldrPin = A1; // Connect the AO pin of the 4-pin LDR sensor to this analog pin

Servo myServo;

void setup() {
  // Set up the stepper motor
  myStepper.setSpeed(50); // Set the motor speed (adjust as needed)

  // Set up servo motor
  myServo.attach(servoPin);

  // Set pin modes for LED and LDR
  pinMode(trayPresentLED, OUTPUT);
}

void loop() {
  // Read the LDR sensor value
  int ldrValue = analogRead(ldrPin);

  // Check if a tray is present using the LDR sensor
  bool trayPresent = ldrValue < 500; // Adjust the threshold value as needed

  // Control the LED based on tray presence
  digitalWrite(trayPresentLED, trayPresent ? HIGH : LOW);

  // Move the stepper motor to the next floor if a tray is inserted
  if (trayPresent) {
    moveStepper(); // Move to the next floor
    delay(2000); // Adjust delay as needed for the stepper motor to reach the next floor
  } else {
    returnServoHome(); // Return the servo to the home position if no trays are present
  }
}

// Function to move the stepper motor to the next floor
void moveStepper() {
  myStepper.step(stepsPerRevolution); // Move to the next floor (1 revolution)
  delay(500); // Adjust delay as needed for the stepper motor movement
}

// Function to return the servo motor to the home position
void returnServoHome() {
  myServo.write(0); // Adjust the angle (0 degrees) to your home position
  delay(1000); // Adjust delay as needed for the servo to reach the home position
}