/**
 * Stars
 * @module src/utility/stars.js
 */

export default function Stars() {
  var canvas = document.createElement("canvas"),
    ctx = canvas.getContext("2d");
  document.body.appendChild(canvas);
  canvas.style.width = "100%";
  canvas.style.height = "100%";
  canvas.style.position = "absolute";
  canvas.style.top = "0px";
  canvas.style.left = "0px";
  canvas.style.zIndex = -1;
  document.body.addEventListener("resize", go);
  document.body.parentNode.style.backgroundColor = "black";
  ctx.strokeStyle = "white";
  var s = Math.sin,
    c = Math.cos;
  go();
  function ri(n) {
    return Math.random() * n;
  }
  function rr(a, b) {
    return (b - a) * Math.random() + a;
  }
  function go() {
    var w = (canvas.width = window.innerWidth);
    var h = (canvas.height = window.innerHeight);
    ctx.clearRect(0, 0, w, h);
    var n = Math.sqrt(w * h) | 0;
    while (n--) {
      var x = ri(w);
      var y = ri(h);
      var r0 = rr(0, 1);
      var r1 = rr(0, 1);
      var r2 = rr(0, 1);
      var t0 = ri(2 * Math.PI);
      var t1 = ri(2 * Math.PI);
      var t2 = ri(2 * Math.PI);
      var x0 = x + c(t0) * r0;
      var y0 = y + s(t0) * r0;
      var x1 = x + c(t1) * r1;
      var y1 = y + s(t1) * r1;
      var x2 = x + c(t2) * r2;
      var y2 = y + s(t2) * r2;
      ctx.beginPath();
      ctx.moveTo(x, y);
      ctx.bezierCurveTo(x0, y0, x1, y1, x2, y2);
      var color = rr(0, 255) | 0;
      ctx.strokeStyle = "rgb(" + color + "," + color + "," + color + ")";
      ctx.stroke();
    }
  }
}