Add test for navigation in summary

1 files changed, 52 insertions, 21 deletions

diff --git a/lib/backbone/summary.js b/lib/backbone/summary.js
index 0d1d0d7..8e1a66d 100644
--- a/lib/backbone/summary.js
+++ b/lib/backbone/summary.js
@@ -79,38 +79,62 @@ TOCArticle.prototype.hasParent = function() {
     return (this.parent instanceof TOCArticle);
 };
 
-// Return next article in the TOC
-TOCArticle.prototype.next = function() {
+// Return a sibling (next or prev) in the parent
+// Withotu taking in consideration children/parent
+TOCArticle.prototype.sibling = function(direction) {
     var parentsArticles = this.parent.articles;
     var pos = _.findIndex(parentsArticles, this);
 
-    if ((pos + 1) >= parentsArticles.length) {
-        if (this.hasParent()) {
-            return this.parent.next();
-        } else {
-            return null;
-        }
-    } else {
-        // next has the same parent
-        return parentsArticles[pos + 1];
+    if (parentsArticles[pos + direction]) {
+        return parentsArticles[pos + direction];
     }
+
+    return null;
 };
 
-// Return previous article in the TOC
-TOCArticle.prototype.prev = function() {
+// Return a sibling (next or prev)
+// It takes parents.children in consideration
+TOCArticle.prototype._sibling = function(direction) {
+    // Next should go to the first children
+    if (direction > 0 && this.hasChildren()) {
+        return _.first(this.articles);
+    }
+
     var parentsArticles = this.parent.articles;
     var pos = _.findIndex(parentsArticles, this);
 
-    if ((pos - 1) < 0) {
-        if (this.hasParent()) {
-            return this.parent.prev();
-        } else {
-            return null;
+    // First child and has parent
+    if (pos == 0 && direction < 0 && this.hasParent()) {
+        return this.parent;
+    }
+
+    // Last child and has parent
+    if(pos == (parentsArticles.length - 1) && direction > 0 && this.hasParent()) {
+        return this.parent.sibling(1);
+    }
+
+    if (parentsArticles[pos + direction]) {
+        var article = parentsArticles[pos + direction];
+
+        // If goign back, take last children from "brother"
+        if (direction < 0 && article.hasChildren()) {
+            article = _.last(article.articles);
         }
-    } else {
-        // prev has the same parent
-        return parentsArticles[pos - 1];
+
+        return article;
     }
+
+    return null;
+};
+
+// Return next article in the TOC
+TOCArticle.prototype.next = function() {
+    return this._sibling(1);
+};
+
+// Return previous article in the TOC
+TOCArticle.prototype.prev = function() {
+    return this._sibling(-1);
 };
 
 // Map over all articles
@@ -228,6 +252,13 @@ Summary.prototype.getArticle = function(page) {
     });
 };
 
+// Return the first TOCArticle for a specific level
+Summary.prototype.getArticleByLevel = function(lvl) {
+    return this.find(function(article) {
+        return article.level == lvl;
+    });
+};
+
 // Return the count of articles in the summary
 Summary.prototype.count = function() {
     return this._length;