add categories

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

diff --git a/ralf/_plugins/categories.rb b/ralf/_plugins/categories.rb
new file mode 100644 (file)
index 0000000..69375da
--- /dev/null
+++ b/ralf/_plugins/categories.rb
@@ -0,0 +1,65 @@
+module Jekyll
+
+  class CategoryPage < Page
+    def initialize(site, base, dir, name, category, layout)
+      @site = site
+      @base = base
+      @dir = dir
+      @name = name
+
+      self.process(@name)
+      self.read_yaml(File.join(base, '_layouts'), layout)
+      self.data['category'] = category
+
+      category_title_prefix = site.config['blog']['category_title_prefix'] || 'Category: '
+      self.data['title'] = "#{category_title_prefix}#{category.capitalize}"
+    end
+  end
+
+  class CategoryPageGenerator < Generator
+    safe true
+
+    def generate(site)
+      dir = site.config['blog']['category_dir'] || 'categories'
+      if site.layouts.key? 'category_index'
+        site.categories.each_key do |category|
+          site.pages << CategoryPage.new(site, site.source, dir, "#{category}.html", category, 'category_index.html')
+        end
+      end
+      if site.layouts.key? 'category_feed'
+        site.categories.each_key do |category|
+          site.pages << CategoryPage.new(site, site.source, dir, "#{category}.xml", category, 'category_feed.html')
+        end
+      end
+    end
+  end
+
+  # Adds some extra filters used during the category creation process.
+  module Filters
+
+    # Outputs a list of categories as comma-separated <a> links. This is used
+    # to output the category list for each post on a category page.
+    #
+    #  +categories+ is the list of categories to format.
+    #
+    # Returns string
+    def category_links(categories)
+      base_dir = @context.registers[:site].config['blog']['category_dir']
+      categories = categories.sort!.map do |category|
+        category_url = File.join(base_dir, "#{category}.html")
+        # Make sure the category directory begins with a slash.
+        category_dir = "/#{category_dir}" unless category_dir =~ /^\//
+        "<a class='category' href='#{category_url}'>#{category.capitalize}</a>"
+      end
+
+      case categories.length
+      when 0
+        ""
+      when 1
+        categories[0].to_s
+      else
+        categories.join(', ')
+      end
+    end
+  end
+end