#include <AccelStepper.h>
#include <PinChangeInterrupt.h>

// Define pins and mottor type.
#define dirPin 5
#define stepPin 6
#define motorInterfaceType 1
#define buttonPin 4 // Define the pin connected to the button
#define encoderClkPin 2
#define encoderDTPin 3

// Variables to manage the stepper and the encoder state:
volatile bool motorEnabled = false; // Motor state flag
volatile unsigned long buttonLastDebounceTime = 0;
unsigned long buttonDebounceDelay = 50;
volatile unsigned long encoderLastDebounceTime = 0;
unsigned long encoderDebounceDelay = 50;
volatile long encoderCount = 0;
long prevEncoderCount = 0;

// Variables for direction of rotation for manual adjustments
int DIRECTION_CW = 1;
int DIRECTION_CCW = -1;
volatile int direction = DIRECTION_CW;

// Create a new instance of the AccelStepper class:
AccelStepper stepper = AccelStepper(motorInterfaceType, stepPin, dirPin);


void setup() {
  stepper.setMaxSpeed(1000);
  pinMode(buttonPin, INPUT_PULLUP);
  attachPinChangeInterrupt(digitalPinToPinChangeInterrupt(buttonPin), toggleMotor, FALLING);

  pinMode(encoderClkPin, INPUT_PULLUP);
  pinMode(encoderDTPin, INPUT_PULLUP);
  attachInterrupt(digitalPinToInterrupt(encoderClkPin), readEncoder, RISING);
}

void toggleMotor() {
  if ((millis() - buttonLastDebounceTime) < buttonDebounceDelay)  {
    return;
  }
  motorEnabled = !motorEnabled;
}

void readEncoder() {
  if ((millis() - encoderLastDebounceTime) < encoderDebounceDelay)  {
    return;
  }
  if (digitalRead(encoderDTPin) == HIGH) {
    encoderCount--;
    direction = DIRECTION_CCW;
  } else {
    encoderCount++;
    direction = DIRECTION_CW;
  }

  encoderLastDebounceTime = millis();  
}

void loop() {
  if (motorEnabled) {
    // Do the automatic rotation step
    stepper.setSpeed(100);
    stepper.runSpeed();
  } else {
    // Do the manual rotation step only if encoder was touched
    if (prevEncoderCount == encoderCount ) {
      return;
    }
    stepper.setSpeed(direction * 100);
    stepper.runSpeed();
    prevEncoderCount = encoderCount;
  }
}