Add unread-class to category children (#6071)

* Add unread-class to category children

* unused variables

* Move child unread-class to a better place

* comma?

¯\_(ツ)_/¯

* feedback

src/categories.js

@@ -153,10 +153,10 @@ Categories.getCategories = function (cids, uid, callback) {
 			uid = parseInt(uid, 10);
 			results.categories.forEach(function (category, i) {
 				if (category) {
-					category['unread-class'] = (parseInt(category.topic_count, 10) === 0 || (results.hasRead[i] && uid !== 0)) ? '' : 'unread';
 					category.children = results.children[i];
 					category.parent = results.parents[i] || undefined;
 					category.tagWhitelist = results.tagWhitelist[i];
+					category['unread-class'] = (parseInt(category.topic_count, 10) === 0 || (results.hasRead[i] && uid !== 0)) ? '' : 'unread';
 					calculateTopicPostCount(category);
 				}
 			});
@@ -259,9 +259,25 @@ function getChildrenRecursive(category, uid, callback) {
 			}
 			Categories.getCategoriesData(children, next);
 		},
-		function (childrenData, next) {
-			childrenData = childrenData.filter(Boolean);
-			category.children = childrenData;
+		function (children, next) {
+			children = children.filter(Boolean);
+			category.children = children;
+
+			var cids = children.map(function (child) {
+				return child.cid;
+			});
+
+			Categories.hasReadCategories(cids, uid, next);
+		},
+		function (hasRead, next) {
+			hasRead.forEach(function (read, i) {
+				var child = category.children[i];
+				child['unread-class'] = (parseInt(child.topic_count, 10) === 0 || (read && uid !== 0)) ? '' : 'unread';
+			});
+
+			next();
+		},
+		function (next) {
 			async.each(category.children, function (child, next) {
 				getChildrenRecursive(child, uid, next);
 			}, next);