From f0ce0533f75f982cd91101853c9b8703530a4fb7 Mon Sep 17 00:00:00 2001
From: cloudhead <self@cloudhead.net>
Date: Fri, 11 Jun 2010 18:18:40 -0400
Subject: [PATCH] refactored and fixed css node creation, for watch mode

---
 lib/less/browser.js | 43 +++++++++++++++++++++++++++++--------------
 1 file changed, 29 insertions(+), 14 deletions(-)

diff --git a/lib/less/browser.js b/lib/less/browser.js
index a1bb3acf..e6937ba0 100644
--- a/lib/less/browser.js
+++ b/lib/less/browser.js
@@ -91,26 +91,39 @@ function loadStyleSheet(sheet, callback) {
 }
 
 function createCSS(styles, sheet, lastModified) {
-    var css = document.createElement('style');
-    css.type = 'text/css';
-    css.media = 'screen';
-    css.title = 'less-sheet';
+    var css, title, id;
 
-    if (sheet) {
-        css.title = sheet.title || sheet.href.match(/(?:^|\/)([-\w]+)\.[a-z]+$/i)[1];
+    // If there is no title set, use the filename, minus the extension
+    title = sheet.title || sheet.href.match(/(?:^|\/)([-\w]+)\.[a-z]+$/i)[1];
+    id = '-less-' + title;
 
-        // Don't update the local store if the file wasn't modified
-        if (lastModified && typeof(localStorage) !== "undefined") {
-            localStorage.setItem(sheet.href, JSON.stringify({ timestamp: lastModified, css: styles }));
-        }
+    // If the stylesheet doesn't exist, create a new node
+    if ((css = document.getElementById(id)) === null) {
+        css = document.createElement('style');
+        css.type = 'text/css';
+        css.media = 'screen';
+        css.title = title;
+        css.id = id;
+        document.getElementsByTagName('head')[0].appendChild(css);
     }
 
-    if (css.styleSheet) {
-        css.styleSheet.cssText = styles;
+    if (css.styleSheet) { // IE
+        try {
+            css.styleSheet.cssText = styles;
+        } catch (e) {
+            throw new(Error)("Couldn't reassign styleSheet.cssText.");
+        }
     } else {
+        if (css.childNodes.length > 0) {
+            css.removeChild(css.childNodes[0]);
+        }
         css.appendChild(document.createTextNode(styles));
     }
-    document.getElementsByTagName('head')[0].appendChild(css);
+
+    // Don't update the local store if the file wasn't modified
+    if (lastModified && typeof(localStorage) !== "undefined") {
+        localStorage.setItem(sheet.href, JSON.stringify({ timestamp: lastModified, css: styles }));
+    }
 }
 
 function xhr(url, callback, errback) {
@@ -158,6 +171,8 @@ function log(str) {
 }
 
 function error(e, href) {
+    if (document.getElementById('less-error-message')) { return }
+
     var template = ['<div>',
                         '<pre class="ctx"><span>[-1]</span>{0}</pre>',
                         '<pre><span>[0]</span>{current}</pre>',
@@ -203,7 +218,7 @@ function error(e, href) {
             'padding-bottom: 2px;',
             'border-bottom: 1px dashed red;',
         '}'
-    ].join(''));
+    ].join(''), { title: 'error-message' });
 
     elem.style.cssText = [
         "font-family: Arial, sans-serif",