// Define pins for stepper motor and driver
const byte DIR_PIN = 2;   // Direction pin
const byte STEP_PIN = 3;  // Step pin
const byte EN_PIN = 4;    // Enable pin

// Define pins for buttons and LEDs
const byte ON_OFF_PIN = 5;   // Button to turn on/off the motor
const byte POT_PIN = A1;      // Potentiometer pin for speed control
const byte LED_PINS[] = {7, 8, 9}; // Array of LED pins for speed indicators
const byte MOTOR_LED_PIN = 10; // LED to indicate motor state

// Define motor steps per revolution
const int SPR = 100;

// Define variables to store current state and speed
boolean state = LOW;        // Motor state (LOW = off, HIGH = on)
byte speedIndex = 0;        // Index of current speed in SPEEDS array
byte stepIndex = 0;
int speedValue = 0;         // Value read from potentiometer

void setup() {
  Serial.begin(115200);

  // Set pin modes
  pinMode(DIR_PIN, OUTPUT);
  pinMode(STEP_PIN, OUTPUT);
  pinMode(EN_PIN, OUTPUT);

  pinMode(ON_OFF_PIN, INPUT_PULLUP); // Enable internal pull-up resistor for button
  pinMode(POT_PIN, INPUT);
  
  for (byte i = 0; i < sizeof(LED_PINS); i++) {
    pinMode(LED_PINS[i], OUTPUT);
  }
  pinMode(MOTOR_LED_PIN, OUTPUT);
  digitalWrite(DIR_PIN, HIGH);

  setMotorState(false);   // Turn off motor initially
}

void loop() {
  static byte prevOnOffState = digitalRead(ON_OFF_PIN);
  byte onOffState = digitalRead(ON_OFF_PIN);
  
  // Read potentiometer value
  speedValue = analogRead(POT_PIN);
  
  if (onOffState != prevOnOffState)  {
    delay(50); // Debounce delay
    prevOnOffState = onOffState;
    if (onOffState == LOW) { // If button is pressed
      state = !state; // Toggle motor state
      setMotorState(state);
    }
  }

  if (state) {
    int interval = map(speedValue, 0, 1023, 5000, 10000); // Map potentiometer value to interval between steps
    if (stepIndex < SPR) {
      digitalWrite(STEP_PIN, HIGH);
      delayMicroseconds(interval/2);
      digitalWrite(STEP_PIN, LOW);
      delayMicroseconds(interval/2);
      stepIndex++;
    } else {
      digitalWrite(DIR_PIN, !digitalRead(DIR_PIN));
      stepIndex = 0;
    }
  }
}

void setMotorState(boolean state) {
  digitalWrite(EN_PIN, !state);    // Enable/disable motor driver
  digitalWrite(MOTOR_LED_PIN, state); // Turn on/off LED to indicate motor state
  setSpeedIndicator(state ? speedIndex : 255); // Turn off all speed indicators when motor is off
}

void setSpeedIndicator(byte speedIndex) {
  for (byte i = 0; i < sizeof(LED_PINS); i++) {
    digitalWrite(LED_PINS[i], (i == speedIndex));
  }
}