pivotalexperimental/style-guide

require "nokogiri"
require "github/markdown"

module StyleGuide
  class Partial
    attr_reader :path, :section

    def initialize(path, section)
      @path = path
      @section = section
    end

    def id
      @id ||= title.downcase.gsub(/[^a-zA-Z0-9]+/, "_")
    end

    def title
      @title ||= File.basename(path, File.extname(path)).titleize.strip
    end

    def description
      @description ||= GitHub::Markdown.render_gfm(translated_description)
    end

    def classes
      @classes ||= begin
        parsed.css("[class]").reduce({}) do |output, tag|
          output.tap do |tags|
            tag["class"].split.each do |class_name|
              tags[".#{class_name}"] = true
            end
          end
        end.keys
      end
    end

    def ids
      @ids ||= parsed.css("[id]").map { |tag| %(##{tag["id"]}) }
    end

    def identifiers
      ids + classes
    end

    def render
      @render ||= action_view.render(:file => path)
    end

    private

    def action_view
      ActionView::Base.new(Rails.root.join("app", "views"))
    end

    def style_guide_scope
      [:style_guide, section.id.to_sym]
    end

    def translated_description
      I18n.translate!(id, :scope => style_guide_scope)
    rescue I18n::MissingTranslationData
      nil
    end

    def parsed
      @parsed ||= Nokogiri::HTML.parse(render)
    end
  end
end