#include <MD_MAX72xx.h>
#include <ezButton.h>

const byte vert = A0;
const byte horz = A1;
const byte sel = 2;

int xhead = 0, yhead = 0;
int maxX = 31, maxY = 7;

byte flag = 0;
String dir = "", prevDir = "";

const byte cs = 10, maxDev = 4;
MD_MAX72XX matrix = MD_MAX72XX(MD_MAX72XX::PAROLA_HW, cs, maxDev);
ezButton btn(sel);

void setup() {
  btn.setDebounceTime(25);
  matrix.begin();
  delay(100);
}

void loop() {
  btn.loop();

  if (flag == 0) {
    checkDir();
    moveSprite();
  }

  matrix.clear();
  matrix.setPoint(yhead, xhead, true);
  delay(100);
}

void checkDir() { 
  if (analogRead(horz) > 512 && prevDir != "right") dir = "left";
  else if (analogRead(horz) < 512 && prevDir != "left") dir = "right";
  else if (analogRead(vert) > 512 && prevDir != "down") dir = "up";
  else if (analogRead(vert) < 512 && prevDir != "up") dir = "down";
  prevDir = dir;
}

void moveSprite() {
  if (dir == "left") xhead++;
  else if (dir == "right") xhead--;
  else if (dir == "down") yhead++;
  else if (dir == "up") yhead--;
  windowCheck();

  if (btn.isPressed()) flag = 1;
}

void windowCheck() {
  if (xhead > maxX) xhead = 0;
  else if (xhead < 0) xhead = maxX;
  else if (yhead > maxY) yhead = 0;
  else if (yhead < 0) yhead = maxY;
}