const { POINTER_TO_DISPLAY } = require('./machine.config');
const { num2hex } = require('./logging.js');

/**
 * Print the contents of display memory
 * by default, each pixel is shown as a hex number
 * @param {Uint8Array} mem - CPU memory
 * @param {Boolean} pretty - Display pixels using black and white emoji circles
 **/
const printDisplay = (mem, pretty=false) => {
  const disp = mem[POINTER_TO_DISPLAY];
  const num2pic = (n) => n > 0 ? '⚫' : '⚪';
  let fmt = (n) => num2hex(n);
  if (pretty) fmt = (n) => num2pic(n);
  for (let i = disp; i < disp + 25; i += 5) {
    console.log(`${fmt(mem[i])} ${fmt(mem[i+1])} ${fmt(mem[i+2])} ${fmt(mem[i+3])} ${fmt(mem[i+4])}`);
  }
}

module.exports = {
  "show": printDisplay,
}