better CSS class handling

src/ScrollBar.js

@@ -4,7 +4,7 @@ ace.ScrollBar = function(parent) {
     this.$initEvents();
 
     this.element = document.createElement("div");
-    this.element.className = "scrollbar";
+    this.element.className = "sb";
 
     this.inner = document.createElement("div");
     this.element.appendChild(this.inner);

src/VirtualRenderer.js

@@ -2,7 +2,7 @@ ace.provide("ace.VirtualRenderer");
 
 ace.VirtualRenderer = function(container) {
     this.container = container;
-    this.container.className += " editor";
+    ace.addCssClass(this.container, "editor");
 
     this.scroller = document.createElement("div");
     this.scroller.className = "scroller";
@@ -233,11 +233,11 @@ ace.VirtualRenderer.prototype.screenToTextCoordinates = function(pageX, pageY) {
 };
 
 ace.VirtualRenderer.prototype.visualizeFocus = function() {
-    //this.container.className = "editor focus";
+    ace.addCssClass(this.container, "focus");
 };
 
 ace.VirtualRenderer.prototype.visualizeBlur = function() {
-    //this.container.className = "editor";
+    ace.removeCssClass(this.container, "focus");
 };
 
 ace.VirtualRenderer.prototype.showComposition = function(position) {

src/ace.js

@@ -78,6 +78,31 @@ ace.preventDefault = function(e) {
         e.returnValue = false;
 };
 
+
+ace.hasCssClass = function(el, name) {
+    var classes = el.className.split(/\s*/g);
+    return ace.arrayIndexOf(classes, name) !== -1; 
+};
+
+
+ace.addCssClass = function(el, name) {
+    if (!ace.hasCssClass(el, name)) {
+        el.className += " " + name;
+    }
+};
+
+ace.removeCssClass = function(el, name) {
+    var classes = el.className.split(/\s+/g);
+    while (true) {
+        var index = ace.arrayIndexOf(classes, name);
+        if (index == -1) {
+            break;
+        }
+        classes.splice(index, 1);
+    }
+    el.className = classes.join(" ");
+};
+
 ace.getInnerWidth = function(element) {
     return (parseInt(ace.computedStyle(element, "paddingLeft"))
             + parseInt(ace.computedStyle(element, "paddingRight")) + element.clientWidth);