// ================= PIN DEFINITIONS =================
#define V_STEP 14
#define V_DIR  12
#define H_STEP 18
#define H_DIR  19
#define EN_PIN 27

// ================= SETTINGS =================
const int stepsPerRow = 800;   // Vertical movement
const int stepsPerCol = 600;   // Horizontal movement

const int ROWS = 6;
const int COLS = 3;

int currentRow = 0;
int currentCol = 0;

// ================= SETUP =================
void setup() {
  Serial.begin(115200);

  pinMode(V_STEP, OUTPUT);
  pinMode(V_DIR, OUTPUT);
  pinMode(H_STEP, OUTPUT);
  pinMode(H_DIR, OUTPUT);
  pinMode(EN_PIN, OUTPUT);

  digitalWrite(EN_PIN, LOW); // Enable A4988

  Serial.println("Enter bin number (0–17):");
}

// ================= LOOP =================
void loop() {
  if (Serial.available()) {
    int bin = Serial.parseInt();
    if (bin >= 0 && bin < ROWS * COLS) {
      moveToBin(bin);
    } else {
      Serial.println("Invalid bin number");
    }
  }
}

// ================= FUNCTIONS =================

void stepMotor(int stepPin, int dirPin, int steps, bool dir) {
  digitalWrite(dirPin, dir);
  for (int i = 0; i < steps; i++) {
    digitalWrite(stepPin, HIGH);
    delayMicroseconds(800);
    digitalWrite(stepPin, LOW);
    delayMicroseconds(800);
  }
}

void moveToBin(int bin) {
  int targetRow = bin / COLS;
  int targetCol = bin % COLS;

  Serial.print("Target Row: ");
  Serial.print(targetRow);
  Serial.print(" | Target Column: ");
  Serial.println(targetCol);

  int rowDiff = targetRow - currentRow;
  int colDiff = targetCol - currentCol;

  if (rowDiff != 0) {
    stepMotor(V_STEP, V_DIR, abs(rowDiff) * stepsPerRow, rowDiff > 0);
    currentRow = targetRow;
  }

  if (colDiff != 0) {
    stepMotor(H_STEP, H_DIR, abs(colDiff) * stepsPerCol, colDiff > 0);
    currentCol = targetCol;
  }

  Serial.print("Reached Bin ");
  Serial.println(bin);
}