Blockly.ScrollbarPair.prototype.resize = function()

in core/scrollbar.js [114:180]
56 lines of code
29 McCabe index (conditional complexity)

Blockly.ScrollbarPair.prototype.resize = function() {
  // Look up the host metrics once, and use for both scrollbars.
  var hostMetrics = this.workspace_.getMetrics();
  if (!hostMetrics) {
    // Host element is likely not visible.
    return;
  }

  // Only change the scrollbars if there has been a change in metrics.
  var resizeH = false;
  var resizeV = false;
  if (!this.oldHostMetrics_ ||
      this.oldHostMetrics_.viewWidth != hostMetrics.viewWidth ||
      this.oldHostMetrics_.viewHeight != hostMetrics.viewHeight ||
      this.oldHostMetrics_.absoluteTop != hostMetrics.absoluteTop ||
      this.oldHostMetrics_.absoluteLeft != hostMetrics.absoluteLeft) {
    // The window has been resized or repositioned.
    resizeH = true;
    resizeV = true;
  } else {
    // Has the content been resized or moved?
    if (!this.oldHostMetrics_ ||
        this.oldHostMetrics_.scrollWidth != hostMetrics.scrollWidth ||
        this.oldHostMetrics_.viewLeft != hostMetrics.viewLeft ||
        this.oldHostMetrics_.scrollLeft != hostMetrics.scrollLeft) {
      resizeH = true;
    }
    if (!this.oldHostMetrics_ ||
        this.oldHostMetrics_.scrollHeight != hostMetrics.scrollHeight ||
        this.oldHostMetrics_.viewTop != hostMetrics.viewTop ||
        this.oldHostMetrics_.scrollTop != hostMetrics.scrollTop) {
      resizeV = true;
    }
  }

  if (resizeH || resizeV) {
    try {
      Blockly.Events.disable();
      if (this.hScroll && resizeH) {
        this.hScroll.resize(hostMetrics);
      }
      if (this.vScroll && resizeV) {
        this.vScroll.resize(hostMetrics);
      }
    } finally {
      Blockly.Events.enable();
    }
    this.workspace_.maybeFireViewportChangeEvent();
  }

  if (this.hScroll && this.vScroll) {
    // Reposition the corner square.
    if (!this.oldHostMetrics_ ||
        this.oldHostMetrics_.viewWidth != hostMetrics.viewWidth ||
        this.oldHostMetrics_.absoluteLeft != hostMetrics.absoluteLeft) {
      this.corner_.setAttribute('x', this.vScroll.position.x);
    }
    if (!this.oldHostMetrics_ ||
        this.oldHostMetrics_.viewHeight != hostMetrics.viewHeight ||
        this.oldHostMetrics_.absoluteTop != hostMetrics.absoluteTop) {
      this.corner_.setAttribute('y', this.hScroll.position.y);
    }
  }

  // Cache the current metrics to potentially short-cut the next resize event.
  this.oldHostMetrics_ = hostMetrics;
};