prepare for having two sites: personal and research

[web.git] / ralf / _plugins / menu.rb

diff --git a/ralf/_plugins/menu.rb b/ralf/_plugins/menu.rb
new file mode 100644 (file)
index 0000000..48befa7
--- /dev/null
+++ b/ralf/_plugins/menu.rb
@@ -0,0 +1,50 @@
+module Jekyll
+  module MenuFilter
+    def menu(input, displayurl)
+      def create_menu(pages, base, displayurl)
+        result = Array.new
+        for page in pages
+          cururl = page['url'].sub('/index.html', '')
+          if cururl.start_with?(base) and cururl.count('/') == base.count('/') and (not page['hide'])
+            # figure out CSS class
+            if cururl == displayurl
+              css_class = 'current'
+            elsif cururl.start_with?(displayurl)
+              css_class = 'child'
+            elsif displayurl.start_with?(cururl)
+              css_class = 'parent'
+            else
+              css_class = 'sibling'
+            end
+            # create menu node
+            menu_node = { 'url' => page['url'], 'title' => page['slug'] ? page['slug'] : (page['title'] ? page['title'] : page['url']), 'class' => css_class, 'sort' => page['sort'] ? page['sort'] : 0 }
+            # potentially recurse
+            if (css_class == 'parent' or css_class == 'current')
+              sub_nodes = create_menu(pages, cururl + "/", displayurl)
+              if sub_nodes.size > 0
+                menu_node['sub'] = sub_nodes
+              end
+              if css_class == 'parent' and sub_nodes.all? { |page| page['class'] == 'sibling' }
+                # we won't get closer to this URL, it doesn't exist in our page list
+                menu_node['class'] = 'current'
+                sub_nodes.each { |page| page['class'] = 'child' }
+              end
+            end
+            # remember the root
+            if base == ""
+              menu_node['class'] += ' root'
+            end
+            # store menu node
+            result.push(menu_node)
+          end
+        end
+        # sort the result before returning it
+        result.sort_by { |page| [page['sort'], page['url']] }
+      end
+      
+      create_menu(input, "", displayurl.sub('/index.html', ''))
+    end
+  end
+end
+
+Liquid::Template.register_filter(Jekyll::MenuFilter)