/** ---------------------------------------------- */
let timer = null;
let time = 0;
function requestAnimationFrame(f) {
  timer = setImmediate(() => {
    time++;
    f(Date.now());
  });
}

const fs = require('fs');
const jsnes = require('../../jsnes-web/node_modules/jsnes');
const { createCanvas } = require('canvas');

var SCREEN_WIDTH = 256;
var SCREEN_HEIGHT = 240;
var FRAMEBUFFER_SIZE = SCREEN_WIDTH * SCREEN_HEIGHT;

var canvas_ctx, image;
var framebuffer_u8, framebuffer_u32;

var nes = new jsnes.NES({
  onFrame: function (framebuffer_24) {
    for (var i = 0; i < FRAMEBUFFER_SIZE; i++) framebuffer_u32[i] = 0xff000000 | framebuffer_24[i];
  },
});

function onAnimationFrame() {
  requestAnimationFrame(onAnimationFrame);
  image.data.set(framebuffer_u8);
  canvas_ctx.putImageData(image, 0, 0);

  let img = canvas_ctx.canvas.toDataURL();
  var data = img.replace(/^data:image\/\w+;base64,/, '');
  var buf = new Buffer(data, 'base64');
  fs.writeFileSync('image.png', buf);

  if (time >= 60 && timer !== null) {
    clearImmediate(timer);
    time = 0;
    process.exit();
  }
}

function nes_init() {
  const canvas = createCanvas(SCREEN_WIDTH, SCREEN_HEIGHT);
  canvas_ctx = canvas.getContext('2d');

  image = canvas_ctx.getImageData(0, 0, SCREEN_WIDTH, SCREEN_HEIGHT);

  canvas_ctx.fillStyle = 'black';
  canvas_ctx.fillRect(0, 0, SCREEN_WIDTH, SCREEN_HEIGHT);

  // Allocate framebuffer array.
  var buffer = new ArrayBuffer(image.data.length);
  framebuffer_u8 = new Uint8ClampedArray(buffer);
  framebuffer_u32 = new Uint32Array(buffer);
}

function nes_boot(rom_data) {
  nes.loadROM(rom_data);

  setInterval(() => {
    nes.frame();
  });

  requestAnimationFrame(onAnimationFrame);
}

function nes_load_url(romData) {
  nes_init();
  nes_boot(romData);
}

module.exports = nes_load_url;

/** ---------------------------------------------- */