/*
  Forum: https://forum.arduino.cc/t/using-a-stepper-motor-between-boundaries/1211483
  Wokwi: https://wokwi.com/projects/387014223071927297
*/

const int motorPin1 = 8;  
const int motorPin2 = 9;
const int motorPin3 = 10;
const int motorPin4 = 11;

const int sensorPin = A0;

//const float minVoltage = 0.42;
//const float maxVoltage = 2.41;
const int   minValue   =  86;
const int   maxValue   = 493;
const int totalSteps = 1020;

int position;
boolean moveLeft = true;
int stepNumber = 0;

void setup() {
  Serial.begin(9600);
  pinMode(motorPin1, OUTPUT);
  pinMode(motorPin2, OUTPUT);
  pinMode(motorPin3, OUTPUT);
  pinMode(motorPin4, OUTPUT);
}

void loop() {
  if (moveLeft){
    turnLeft();
  } else {
    turnRight();
  }
 
}

int sensorValue(){
 return analogRead(sensorPin);
}

void turnLeft(){
  position = sensorValue();
  if (position > minValue){
    stepMotor(-1);
    stepNumber--;
  } else {
    moveLeft = false;
  }
}

void turnRight(){
  position = sensorValue();
  if (position < maxValue){
    stepMotor(1);
    stepNumber++;
  } else {
    moveLeft = true;
  }
}

void stepMotor(int dir){
  Serial.println(position);
  if (dir == 1){
    for (int i = 0;i <= 3;i++ ){
      step(i);
    }
  } else {
    for (int i = 3; i >= 0;i-- ){
      step(i);
    }
  }
}


void step(int aStep) {
  switch (aStep) {
    case 0:
      digitalWrite(motorPin1, LOW);
      digitalWrite(motorPin2, LOW);
      digitalWrite(motorPin3, HIGH);
      digitalWrite(motorPin4, LOW);
      break;
    case 1:
      digitalWrite(motorPin1, LOW);
      digitalWrite(motorPin2, HIGH);
      digitalWrite(motorPin3, LOW);
      digitalWrite(motorPin4, LOW);
      break;
    case 2:
      digitalWrite(motorPin1, LOW);
      digitalWrite(motorPin2, LOW);
      digitalWrite(motorPin3, LOW);
      digitalWrite(motorPin4, HIGH);
      break;
    case 3:
      digitalWrite(motorPin1, HIGH);
      digitalWrite(motorPin2, LOW);
      digitalWrite(motorPin3, LOW);
      digitalWrite(motorPin4, LOW);
      break;
  }
  delay(10);
}