confetti.js

(function main(global, module, isWorker, workerSize) {
  var canUseWorker = !!(
    global.Worker &&
    global.Blob &&
    global.Promise &&
    global.OffscreenCanvas &&
    global.OffscreenCanvasRenderingContext2D &&
    global.HTMLCanvasElement &&
    global.HTMLCanvasElement.prototype.transferControlToOffscreen &&
    global.URL &&
    global.URL.createObjectURL);

  function noop() {}

  // create a promise if it exists, otherwise, just
  // call the function directly
  function promise(func) {
    var ModulePromise = module.exports.Promise;
    var Prom = ModulePromise !== void 0 ? ModulePromise : global.Promise;

    if (typeof Prom === 'function') {
      return new Prom(func);
    }

    func(noop, noop);

    return null;
  }

  var raf = (function () {
    var TIME = Math.floor(1000 / 60);
    var frame, cancel;
    var frames = {};
    var lastFrameTime = 0;

    if (typeof requestAnimationFrame === 'function' && typeof cancelAnimationFrame === 'function') {
      frame = function (cb) {
        var id = Math.random();

        frames[id] = requestAnimationFrame(function onFrame(time) {
          if (lastFrameTime === time || lastFrameTime + TIME - 1 < time) {
            lastFrameTime = time;
            delete frames[id];

            cb();
          } else {
            frames[id] = requestAnimationFrame(onFrame);
          }
        });

        return id;
      };
      cancel = function (id) {
        if (frames[id]) {
          cancelAnimationFrame(frames[id]);
        }
      };
    } else {
      frame = function (cb) {
        return setTimeout(cb, TIME);
      };
      cancel = function (timer) {
        return clearTimeout(timer);
      };
    }

    return { frame: frame, cancel: cancel };
  }());

  var getWorker = (function () {
    var worker;
    var prom;
    var resolves = {};

    function decorate(worker) {
      function execute(options, callback) {
        worker.postMessage({ options: options || {}, callback: callback });
      }
      worker.init = function initWorker(canvas) {
        var offscreen = canvas.transferControlToOffscreen();
        worker.postMessage({ canvas: offscreen }, [offscreen]);
      };

      worker.fire = function fireWorker(options, size, done) {
        if (prom) {
          execute(options, null);
          return prom;
        }

        var id = Math.random().toString(36).slice(2);

        prom = promise(function (resolve) {
          function workerDone(msg) {
            if (msg.data.callback !== id) {
              return;
            }

            delete resolves[id];
            worker.removeEventListener('message', workerDone);

            prom = null;
            done();
            resolve();
          }

          worker.addEventListener('message', workerDone);
          execute(options, id);

          resolves[id] = workerDone.bind(null, { data: { callback: id }});
        });

        return prom;
      };

      worker.reset = function resetWorker() {
        worker.postMessage({ reset: true });

        for (var id in resolves) {
          resolves[id]();
          delete resolves[id];
        }
      };
    }

    return function () {
      if (worker) {
        return worker;
      }

      if (!isWorker && canUseWorker) {
        var code = [
          'var CONFETTI, SIZE = {}, module = {};',
          '(' + main.toString() + ')(this, module, true, SIZE);',
          'onmessage = function(msg) {',
          '  if (msg.data.options) {',
          '    CONFETTI(msg.data.options).then(function () {',
          '      if (msg.data.callback) {',
          '        postMessage({ callback: msg.data.callback });',
          '      }',
          '    });',
          '  } else if (msg.data.reset) {',
          '    CONFETTI && CONFETTI.reset();',
          '  } else if (msg.data.resize) {',
          '    SIZE.width = msg.data.resize.width;',
          '    SIZE.height = msg.data.resize.height;',
          '  } else if (msg.data.canvas) {',
          '    SIZE.width = msg.data.canvas.width;',
          '    SIZE.height = msg.data.canvas.height;',
          '    CONFETTI = module.exports.create(msg.data.canvas);',
          '  }',
          '}',
        ].join('\n');
        try {
          worker = new Worker(URL.createObjectURL(new Blob([code])));
        } catch (e) {
          // eslint-disable-next-line no-console
          typeof console !== undefined && typeof console.warn === 'function' ? console.warn('🎊 Could not load worker', e) : null;

          return null;
        }

        decorate(worker);
      }

      return worker;
    };
  })();

  var defaults = {
    particleCount: 50,
    angle: 90,
    spread: 45,
    startVelocity: 45,
    decay: 0.9,
    gravity: 1,
    drift: 0,
    ticks: 200,
    x: 0.5,
    y: 0.5,
    shapes: ['square', 'circle'],
    zIndex: 100,
    colors: [
      '#26ccff',
      '#a25afd',
      '#ff5e7e',
      '#88ff5a',
      '#fcff42',
      '#ffa62d',
      '#ff36ff'
    ],
    // probably should be true, but back-compat
    disableForReducedMotion: false,
    scalar: 1
  };

  function convert(val, transform) {
    return transform ? transform(val) : val;
  }

  function isOk(val) {
    return !(val === null || val === undefined);
  }

  function prop(options, name, transform) {
    return convert(
      options && isOk(options[name]) ? options[name] : defaults[name],
      transform
    );
  }

  function onlyPositiveInt(number){
    return number < 0 ? 0 : Math.floor(number);
  }

  function randomInt(min, max) {
    // [min, max)
    return Math.floor(Math.random() * (max - min)) + min;
  }

  function toDecimal(str) {
    return parseInt(str, 16);
  }

  function colorsToRgb(colors) {
    return colors.map(hexToRgb);
  }

  function hexToRgb(str) {
    var val = String(str).replace(/[^0-9a-f]/gi, '');

    if (val.length < 6) {
        val = val[0]+val[0]+val[1]+val[1]+val[2]+val[2];
    }

    return {
      r: toDecimal(val.substring(0,2)),
      g: toDecimal(val.substring(2,4)),
      b: toDecimal(val.substring(4,6))
    };
  }

  function getOrigin(options) {
    var origin = prop(options, 'origin', Object);
    origin.x = prop(origin, 'x', Number);
    origin.y = prop(origin, 'y', Number);

    return origin;
  }

  function setCanvasWindowSize(canvas) {
    canvas.width = document.documentElement.clientWidth;
    canvas.height = document.documentElement.clientHeight;
  }

  function setCanvasRectSize(canvas) {
    var rect = canvas.getBoundingClientRect();
    canvas.width = rect.width;
    canvas.height = rect.height;
  }

  function getCanvas(zIndex) {
    var canvas = document.createElement('canvas');

    canvas.style.position = 'fixed';
    canvas.style.top = '0px';
    canvas.style.left = '0px';
    canvas.style.pointerEvents = 'none';
    canvas.style.zIndex = zIndex;

    return canvas;
  }

  function ellipse(context, x, y, radiusX, radiusY, rotation, startAngle, endAngle, antiClockwise) {
    context.save();
    context.translate(x, y);
    context.rotate(rotation);
    context.scale(radiusX, radiusY);
    context.arc(0, 0, 1, startAngle, endAngle, antiClockwise);
    context.restore();
  }

  function randomPhysics(opts) {
    var radAngle = opts.angle * (Math.PI / 180);
    var radSpread = opts.spread * (Math.PI / 180);

    return {
      x: opts.x,
      y: opts.y,
      wobble: Math.random() * 10,
      wobbleSpeed: Math.min(0.11, Math.random() * 0.1 + 0.05),
      velocity: (opts.startVelocity * 0.5) + (Math.random() * opts.startVelocity),
      angle2D: -radAngle + ((0.5 * radSpread) - (Math.random() * radSpread)),
      tiltAngle: (Math.random() * (0.75 - 0.25) + 0.25) * Math.PI,
      color: opts.color,
      shape: opts.shape,
      tick: 0,
      totalTicks: opts.ticks,
      decay: opts.decay,
      drift: opts.drift,
      random: Math.random() + 2,
      tiltSin: 0,
      tiltCos: 0,
      wobbleX: 0,
      wobbleY: 0,
      gravity: opts.gravity * 3,
      ovalScalar: 0.6,
      scalar: opts.scalar
    };
  }

  function updateFetti(context, fetti) {
    fetti.x += Math.cos(fetti.angle2D) * fetti.velocity + fetti.drift;
    fetti.y += Math.sin(fetti.angle2D) * fetti.velocity + fetti.gravity;
    fetti.wobble += fetti.wobbleSpeed;
    fetti.velocity *= fetti.decay;
    fetti.tiltAngle += 0.1;
    fetti.tiltSin = Math.sin(fetti.tiltAngle);
    fetti.tiltCos = Math.cos(fetti.tiltAngle);
    fetti.random = Math.random() + 2;
    fetti.wobbleX = fetti.x + ((10 * fetti.scalar) * Math.cos(fetti.wobble));
    fetti.wobbleY = fetti.y + ((10 * fetti.scalar) * Math.sin(fetti.wobble));

    var progress = (fetti.tick++) / fetti.totalTicks;

    var x1 = fetti.x + (fetti.random * fetti.tiltCos);
    var y1 = fetti.y + (fetti.random * fetti.tiltSin);
    var x2 = fetti.wobbleX + (fetti.random * fetti.tiltCos);
    var y2 = fetti.wobbleY + (fetti.random * fetti.tiltSin);

    context.fillStyle = 'rgba(' + fetti.color.r + ', ' + fetti.color.g + ', ' + fetti.color.b + ', ' + (1 - progress) + ')';
    context.beginPath();

    if (fetti.shape === 'circle') {
      context.ellipse ?
        context.ellipse(fetti.x, fetti.y, Math.abs(x2 - x1) * fetti.ovalScalar, Math.abs(y2 - y1) * fetti.ovalScalar, Math.PI / 10 * fetti.wobble, 0, 2 * Math.PI) :
        ellipse(context, fetti.x, fetti.y, Math.abs(x2 - x1) * fetti.ovalScalar, Math.abs(y2 - y1) * fetti.ovalScalar, Math.PI / 10 * fetti.wobble, 0, 2 * Math.PI);
    } else if (fetti.shape === 'star') {
      var rot = Math.PI / 2 * 3;
      var innerRadius = 4 * fetti.scalar;
      var outerRadius = 8 * fetti.scalar;
      var x = fetti.x;
      var y = fetti.y;
      var spikes = 5;
      var step = Math.PI / spikes;

      while (spikes--) {
        x = fetti.x + Math.cos(rot) * outerRadius;
        y = fetti.y + Math.sin(rot) * outerRadius;
        context.lineTo(x, y);
        rot += step;

        x = fetti.x + Math.cos(rot) * innerRadius;
        y = fetti.y + Math.sin(rot) * innerRadius;
        context.lineTo(x, y);
        rot += step;
      }
    } else {
      context.moveTo(Math.floor(fetti.x), Math.floor(fetti.y));
      context.lineTo(Math.floor(fetti.wobbleX), Math.floor(y1));
      context.lineTo(Math.floor(x2), Math.floor(y2));
      context.lineTo(Math.floor(x1), Math.floor(fetti.wobbleY));
    }

    context.closePath();
    context.fill();

    return fetti.tick < fetti.totalTicks;
  }

  function animate(canvas, fettis, resizer, size, done) {
    var animatingFettis = fettis.slice();
    var context = canvas.getContext('2d');
    var animationFrame;
    var destroy;

    var prom = promise(function (resolve) {
      function onDone() {
        animationFrame = destroy = null;

        context.clearRect(0, 0, size.width, size.height);

        done();
        resolve();
      }

      function update() {
        if (isWorker && !(size.width === workerSize.width && size.height === workerSize.height)) {
          size.width = canvas.width = workerSize.width;
          size.height = canvas.height = workerSize.height;
        }

        if (!size.width && !size.height) {
          resizer(canvas);
          size.width = canvas.width;
          size.height = canvas.height;
        }

        context.clearRect(0, 0, size.width, size.height);

        animatingFettis = animatingFettis.filter(function (fetti) {
          return updateFetti(context, fetti);
        });

        if (animatingFettis.length) {
          animationFrame = raf.frame(update);
        } else {
          onDone();
        }
      }

      animationFrame = raf.frame(update);
      destroy = onDone;
    });

    return {
      addFettis: function (fettis) {
        animatingFettis = animatingFettis.concat(fettis);

        return prom;
      },
      canvas: canvas,
      promise: prom,
      reset: function () {
        if (animationFrame) {
          raf.cancel(animationFrame);
        }

        if (destroy) {
          destroy();
        }
      }
    };
  }

  function confettiCannon(canvas, globalOpts) {
    var isLibCanvas = !canvas;
    var allowResize = !!prop(globalOpts || {}, 'resize');
    var globalDisableForReducedMotion = prop(globalOpts, 'disableForReducedMotion', Boolean);
    var shouldUseWorker = canUseWorker && !!prop(globalOpts || {}, 'useWorker');
    var worker = shouldUseWorker ? getWorker() : null;
    var resizer = isLibCanvas ? setCanvasWindowSize : setCanvasRectSize;
    var initialized = (canvas && worker) ? !!canvas.__confetti_initialized : false;
    var preferLessMotion = typeof matchMedia === 'function' && matchMedia('(prefers-reduced-motion)').matches;
    var animationObj;

    function fireLocal(options, size, done) {
      var particleCount = prop(options, 'particleCount', onlyPositiveInt);
      var angle = prop(options, 'angle', Number);
      var spread = prop(options, 'spread', Number);
      var startVelocity = prop(options, 'startVelocity', Number);
      var decay = prop(options, 'decay', Number);
      var gravity = prop(options, 'gravity', Number);
      var drift = prop(options, 'drift', Number);
      var colors = prop(options, 'colors', colorsToRgb);
      var ticks = prop(options, 'ticks', Number);
      var shapes = prop(options, 'shapes');
      var scalar = prop(options, 'scalar');
      var origin = getOrigin(options);

      var temp = particleCount;
      var fettis = [];

      var startX = canvas.width * origin.x;
      var startY = canvas.height * origin.y;

      while (temp--) {
        fettis.push(
          randomPhysics({
            x: startX,
            y: startY,
            angle: angle,
            spread: spread,
            startVelocity: startVelocity,
            color: colors[temp % colors.length],
            shape: shapes[randomInt(0, shapes.length)],
            ticks: ticks,
            decay: decay,
            gravity: gravity,
            drift: drift,
            scalar: scalar
          })
        );
      }

      // if we have a previous canvas already animating,
      // add to it
      if (animationObj) {
        return animationObj.addFettis(fettis);
      }

      animationObj = animate(canvas, fettis, resizer, size , done);

      return animationObj.promise;
    }

    function fire(options) {
      var disableForReducedMotion = globalDisableForReducedMotion || prop(options, 'disableForReducedMotion', Boolean);
      var zIndex = prop(options, 'zIndex', Number);

      if (disableForReducedMotion && preferLessMotion) {
        return promise(function (resolve) {
          resolve();
        });
      }

      if (isLibCanvas && animationObj) {
        // use existing canvas from in-progress animation
        canvas = animationObj.canvas;
      } else if (isLibCanvas && !canvas) {
        // create and initialize a new canvas
        canvas = getCanvas(zIndex);
        document.body.appendChild(canvas);
      }

      if (allowResize && !initialized) {
        // initialize the size of a user-supplied canvas
        resizer(canvas);
      }

      var size = {
        width: canvas.width,
        height: canvas.height
      };

      if (worker && !initialized) {
        worker.init(canvas);
      }

      initialized = true;

      if (worker) {
        canvas.__confetti_initialized = true;
      }

      function onResize() {
        if (worker) {
          // TODO this really shouldn't be immediate, because it is expensive
          var obj = {
            getBoundingClientRect: function () {
              if (!isLibCanvas) {
                return canvas.getBoundingClientRect();
              }
            }
          };

          resizer(obj);

          worker.postMessage({
            resize: {
              width: obj.width,
              height: obj.height
            }
          });
          return;
        }

        // don't actually query the size here, since this
        // can execute frequently and rapidly
        size.width = size.height = null;
      }

      function done() {
        animationObj = null;

        if (allowResize) {
          global.removeEventListener('resize', onResize);
        }

        if (isLibCanvas && canvas) {
          document.body.removeChild(canvas);
          canvas = null;
          initialized = false;
        }
      }

      if (allowResize) {
        global.addEventListener('resize', onResize, false);
      }

      if (worker) {
        return worker.fire(options, size, done);
      }

      return fireLocal(options, size, done);
    }

    fire.reset = function () {
      if (worker) {
        worker.reset();
      }

      if (animationObj) {
        animationObj.reset();
      }
    };

    return fire;
  }

  // Make default export lazy to defer worker creation until called.
  var defaultFire;
  function getDefaultFire() {
    if (!defaultFire) {
      defaultFire = confettiCannon(null, { useWorker: true, resize: true });
    }
    return defaultFire;
  }

  module.exports = function() {
    return getDefaultFire().apply(this, arguments);
  };
  module.exports.reset = function() {
    getDefaultFire().reset();
  };
  module.exports.create = confettiCannon;
}((function () {
  if (typeof window !== 'undefined') {
    return window;
  }

  if (typeof self !== 'undefined') {
    return self;
  }

  return this || {};
})(), module, false));