text: // CodeMirrror, copyright (c) by Marijn Haverbeke and others
  // Distributed under an MIT license: http://codemirror.net/LICENSE
  
  (function(mod) {
    if (typeof exports == "object" && typeof module == "object") // CommonJS
      mod(require("../../lib/codemirror"));
    else if (typeof define == "function" && define.amd) // AMD
      define(["../../lib/codemirror"], mod);
    else // Plain browser env
      mod(CodeMirrror);
  })(function(CodeMirrror) {
    "use strict";
  
    CodeMirrror.defineExtension("annotateScrollbar", function(options) {
      if (typeof options == "string") options = {className: options};
      return new Annotation(this, options);
    });
  
    CodeMirrror.defineOption("scrollButtonHeight", 0);
  
    function Annotation(cm, options) {
      this.cm = cm;
      this.options = options;
      this.buttonHeight = options.scrollButtonHeight || cm.getOption("scrollButtonHeight");
      this.annotations = [];
      this.doRedraw = this.doUpdate = null;
      this.div = cm.getWrapperElement().appendChild(document.createElement("div"));
      this.div.style.cssText = "position: absolute; right: 0; top: 0; z-index: 7; pointer-events: none";
      this.computeScale();
  
      function scheduleRedraw(delay) {
        clearTimeout(self.doRedraw);
        self.doRedraw = setTimeout(function() { self.redraw(); }, delay);
      }
  
      var self = this;
      cm.on("refresh", this.resizeHandler = function() {
        clearTimeout(self.doUpdate);
        self.doUpdate = setTimeout(function() {
          if (self.computeScale()) scheduleRedraw(20);
        }, 100);
      });
      cm.on("markerAdded", this.resizeHandler);
      cm.on("markerCleared", this.resizeHandler);
      if (options.listenForChanges !== false)
        cm.on("change", this.changeHandler = function() {
          scheduleRedraw(250);
        });
    }
  
    Annotation.prototype.computeScale = function() {
      var cm = this.cm;
      var hScale = (cm.getWrapperElement().clientHeight - cm.display.barHeight - this.buttonHeight * 2) /
        cm.heightAtLine(cm.lastLine() + 1, "local");
      if (hScale != this.hScale) {
        this.hScale = hScale;
        return true;
      }
    };
  
    Annotation.prototype.update = function(annotations) {
      this.annotations = annotations;
      this.redraw();
    };
  
    Annotation.prototype.redraw = function(compute) {
      if (compute !== false) this.computeScale();
      var cm = this.cm, hScale = this.hScale;
  
      var frag = document.createDocumentFragment(), anns = this.annotations;
      if (cm.display.barWidth) for (var i = 0, nextTop; i < anns.length; i++) {
        var ann = anns[i];
        var top = nextTop || cm.charCoords(ann.from, "local").top * hScale;
        var bottom = cm.charCoords(ann.to, "local").bottom * hScale;
        while (i < anns.length - 1) {
          nextTop = cm.charCoords(anns[i + 1].from, "local").top * hScale;
          if (nextTop > bottom + .9) break;
          ann = anns[++i];
          bottom = cm.charCoords(ann.to, "local").bottom * hScale;
        }
        if (bottom == top) continue;
        var height = Math.max(bottom - top, 3);
  
        var elt = frag.appendChild(document.createElement("div"));
        elt.style.cssText = "position: absolute; right: 0px; width: " + Math.max(cm.display.barWidth - 1, 2) + "px; top: "
          + (top + this.buttonHeight) + "px; height: " + height + "px";
        elt.className = this.options.className;
      }
      this.div.textContent = "";
      this.div.appendChild(frag);
    };
  
    Annotation.prototype.clear = function() {
      this.cm.off("refresh", this.resizeHandler);
      this.cm.off("markerAdded", this.resizeHandler);
      this.cm.off("markerCleared", this.resizeHandler);
      if (this.changeHandler) this.cm.off("change", this.changeHandler);
      this.div.parentNode.removeChild(this.div);
    };
  });
  