module Rack::Insight
  class TemplatesPanel

    class Rendering
      attr_accessor :name
      attr_accessor :parent
      attr_accessor :timing
      attr_reader :children

      def initialize(name, timing = nil)
        @name = name
        @timing = timing
        @children = []
      end

      def start_time
        @timing.start
      end
      alias_method :time, :start_time

      def end_time
        @timing.end
      end

      def add(rendering)
        @children << rendering
        rendering.parent = self
      end

      def delete(rendering)
        @children.delete(rendering)
      end

      def duration
        if @timing
          @timing.duration
        else
          child_duration
        end
      end

      def exclusive_duration
        duration - child_duration
      end

      def child_duration
        children.inject(0.0) { |memo, c| memo + c.duration }
      end

      def duration_summary
        if children.any?
          "%.2fms, %.2f exclusive" % [duration, exclusive_duration]
        else
          "%.2fms" % (duration)
        end
      end
      def html
        <<-HTML
            <li>
              <p>#{name} (#{duration_summary})</p>

        #{children_html}
            </li>
        HTML
      end

      def children_html
        return "" unless children.any?

        <<-HTML
            <ul>#{joined_children_html}</ul>
        HTML
      end

      def joined_children_html
        children.map { |c| c.html }.join
      end
    end

  end
end