Optimize and fix autolink function (#1442) (#1444)

* Optimize and fix autolink function (#1442)

* Fix bug in autolink recursive fallback function

public/js/libs/autolink.js

@@ -1,15 +1,45 @@
-jQuery.fn.autolink = function() {
+(function () {
     var re = /((([A-Za-z]{3,9}:(?:\/\/)?)(?:[\-;:&=\+\$,\w]+@)?[A-Za-z0-9\.\-]+|(?:www\.|[\-;:&=\+\$,\w]+@)[A-Za-z0-9\.\-]+)((?:\/[\+~%\/\.\w\-]*)?\??(?:[\-\+:=&;%@\.\w]*)#?(?:[\.\!\/\\\w]*))?)/g;
-	return this.find('*').contents()
-		.filter(function () { return this.nodeType === 3; })
-		.each(function() {
-			$(this).each(function() {
-				if (re.test($(this).text()))
-					$(this).replaceWith(
-						$("<span />").html(
-							this.nodeValue.replace(re, "<a href='$1'>$1</a>")
+    function textNodesUnder(node) {
+        var textNodes = [];
+        if(typeof document.createTreeWalker === 'function') {
+            // Efficient TreeWalker
+            var currentNode, walker;
+            walker = document.createTreeWalker(node, NodeFilter.SHOW_TEXT, null, false);
+            while(currentNode = walker.nextNode()) {
+                textNodes.push(currentNode);
+            }
+        } else {
+            // Less efficient recursive function
+            for(node = node.firstChild; node; node = node.nextSibling) {
+                if(node.nodeType === 3) {
+                    textNodes.push(node);
+                } else {
+                    textNodes = textNodes.concat(textNodesUnder(node));
+                }
+            }
+        }
+        return textNodes;
+    }
+
+    function processNode(node) {
+        re.lastIndex = 0;
+        var results = re.exec(node.textContent);
+        if(results !== null) {
+            if($(node).parents().filter('pre>code').length === 0) {
+                $(node).replaceWith(
+                    $('<span />').html(
+                        node.nodeValue.replace(re, '<a href="$1">$1</a>')
                     )
                 );
+            }
+        }
+    }
+
+    jQuery.fn.autolink = function () {
+        this.each(function () {
+            textNodesUnder(this).forEach(processNode);
         });
-		});
+        return this;
     };
+})();