Flipsnap.prototype._touchMove = function()

in harness/app-assets/templates/assets/js/components/flipsnap.js [306:367]
54 lines of code
12 McCabe index (conditional complexity)

Flipsnap.prototype._touchMove = function(event, type) {
  var self = this;

  if (!self.scrolling || gestureStart) {
    return;
  }

  var pageX = getPage(event, 'pageX');
  var pageY = getPage(event, 'pageY');
  var distX;
  var newX;

  if (self.moveReady) {
    event.preventDefault();

    distX = pageX - self.basePageX;
    newX = self.currentX + distX;
    if (newX >= 0 || newX < self._maxX) {
      newX = Math.round(self.currentX + distX / 3);
    }

    // When distX is 0, use one previous value.
    // For android firefox. When touchend fired, touchmove also
    // fired and distX is certainly set to 0. 
    self.directionX =
      distX === 0 ? self.directionX :
      distX > 0 ? -1 : 1;

    // if they prevent us then stop it
    var isPrevent = !self._triggerEvent('fstouchmove', true, true, {
      delta: distX,
      direction: self.directionX
    });

    if (isPrevent) {
      self._touchAfter({
        moved: false,
        originalPoint: self.currentPoint,
        newPoint: self.currentPoint,
        cancelled: true
      });
    } else {
      self._setX(newX);
    }
  }
  else {
    // https://github.com/hokaccha/js-flipsnap/pull/36
    var triangle = getTriangleSide(self.startPageX, self.startPageY, pageX, pageY);
    if (triangle.z > DISTANCE_THRESHOLD) {
      if (getAngle(triangle) > ANGLE_THREHOLD) {
        event.preventDefault();
        self.moveReady = true;
        self.element.addEventListener('click', self, true);
      }
      else {
        self.scrolling = false;
      }
    }
  }

  self.basePageX = pageX;
};