//Get window size
var ww = window.innerWidth,
  wh = window.innerHeight;

//Create a WebGL renderer
var renderer = new THREE.WebGLRenderer({
  canvas: document.querySelector("canvas")
});
renderer.setSize(ww, wh);

//Create an empty scene
var scene = new THREE.Scene();
scene.fog = new THREE.Fog(0x000000, 30, 150);

//Create a perpsective camera
var camera = new THREE.PerspectiveCamera(45, ww / wh, 0.1, 150);
camera.position.y = 400;
camera.position.z = 400;

//Array of points
var points = [
  [68.5, 185.5],
  [1, 262.5],
  [270.9, 281.9],
  [345.5, 212.8],
  [178, 155.7],
  [240.3, 72.3],
  [153.4, 0.6],
  [52.6, 53.3],
  [68.5, 185.5]
];

//Convert the array of points into vertices
for (var i = 0; i < points.length; i++) {
  var x = points[i][0];
  var y = Math.random() * 100;
  var z = points[i][1];
  points[i] = new THREE.Vector3(x, y, z);
}
//Create a path from the points
var path = new THREE.CatmullRomCurve3(points);
path.closed = true;

// Define the precision of the finale tube, the amount of divisions
var tubeDetail = 1600;
// Define the precision of the circles
var circlesDetail = 40;

// Define the radius of the finale tube
var radius = 4;
// Get all the circles that will compose the tube
var frames = path.computeFrenetFrames(tubeDetail, true);

// Create an empty Geometry where we will put the particles
var geometry = new THREE.Geometry();

// Define a basic color
var color = new THREE.Color(0x000000);

// First loop through all the circles
for (var i = 0; i < tubeDetail; i++) {
  // Get the normal values for each circle
  var normal = frames.normals[i];
  // Get the binormal values
  var binormal = frames.binormals[i];

  // Calculate the index of the circle (from 0 to 1)
  var index = i / tubeDetail;
  // Get the coordinates of the point in the center of the circle
  var p = path.getPointAt(index);

  // Loop for the amount of particles we want along each circle
  for (var j = 0; j < circlesDetail; j++) {
    // Clone the position of the point in the center
    var position = p.clone();

    // Calculate the angle for each particle along the circle (from 0 to Pi*2)
    var angle = (j / circlesDetail) * Math.PI * 2 + (index * Math.PI * 5);
    // Calculate the sine of the angle
    var sin = Math.sin(angle);
    // Calculate the cosine from the angle
    var cos = -Math.cos(angle);

    // Calculate the normal of each point based on its angle
    var normalPoint = new THREE.Vector3(0, 0, 0);
    normalPoint.x = (cos * normal.x + sin * binormal.x);
    normalPoint.y = (cos * normal.y + sin * binormal.y);
    normalPoint.z = (cos * normal.z + sin * binormal.z);
    // Multiple the normal by the radius
    normalPoint.multiplyScalar(radius);

    // We add the normal values for each point
    position.add(normalPoint);
    var color = new THREE.Color("hsl(" + (index * 360 * 4) + ", 100%, 50%)");
    geometry.colors.push(color);
    geometry.vertices.push(position);
  }
}

// Material for the points
var material = new THREE.PointsMaterial({
  size: 0.2,
  vertexColors: THREE.VertexColors
});

var tube = new THREE.Points(geometry, material);
//Add tube into the scene
scene.add(tube);

var percentage = 0;

function render() {

  percentage += 0.0005;
  var p1 = path.getPointAt(percentage % 1);
  var p2 = path.getPointAt((percentage + 0.01) % 1);
  camera.position.set(p1.x, p1.y, p1.z);
  camera.lookAt(p2);

  //Render the scene
  renderer.render(scene, camera);

  requestAnimationFrame(render);
}
requestAnimationFrame(render);