sort posts

examples/gno.land/p/demo/blog/blog.gno

@@ -42,11 +42,20 @@ func (b Blog) RenderHome(res *mux.ResponseWriter, req *mux.Request) {
 	}
 
 	res.Write("<div class='columns-3'>")
+
+	var sorted []*Post
 	b.Posts.Iterate("", "", func(key string, value interface{}) bool {
 		post := value.(*Post)
-		res.Write(post.RenderListItem())
+		sorted = append(sorted, post)
 		return false
 	})
+
+	sorted = mergeSort(sorted)
+
+	for _, post := range sorted {
+		res.Write(post.RenderListItem())
+	}
+
 	res.Write("</div>")
 
 	// FIXME: tag list/cloud.

examples/gno.land/p/demo/blog/util.gno

@@ -5,3 +5,37 @@ import "strings"
 func breadcrumb(parts []string) string {
 	return "# " + strings.Join(parts, " / ") + "\n\n"
 }
+
+func merge(left, right []*Post) []*Post {
+	result := make([]*Post, 0, len(left)+len(right))
+
+	for len(left) > 0 || len(right) > 0 {
+		if len(left) == 0 {
+			return append(result, right...)
+		}
+		if len(right) == 0 {
+			return append(result, left...)
+		}
+		if left[0].CreatedAt.After(right[0].CreatedAt) {
+			result = append(result, left[0])
+			left = left[1:]
+		} else {
+			result = append(result, right[0])
+			right = right[1:]
+		}
+	}
+
+	return result
+}
+
+func mergeSort(posts []*Post) []*Post {
+	if len(posts) <= 1 {
+		return posts
+	}
+
+	middle := len(posts) / 2
+	left := mergeSort(posts[:middle])
+	right := mergeSort(posts[middle:])
+
+	return merge(left, right)
+}