module Vedeu

  module Renderers

    # Renders a {Vedeu::VirtualBuffer} or {Vedeu::Output} as a HTML snippet;
    # a table by default.
    #
    class HTML < Vedeu::Renderers::File

      # Returns a new instance of Vedeu::Renderers::HTML.
      #
      # @param options [Hash]
      # @option options content [String]
      # @option options end_row_tag [String]
      # @option options start_row_tag [String]
      # @option options template [String]
      # @return [Vedeu::Renderers::HTML]
      def initialize(options = {})
        @options = options || {}
      end

      # @param output [Array<Array<Vedeu::Char>>]
      # @return [String]
      def render(output)
        @options[:content] = output

        if write_file?
          super(Vedeu::Templating::Template.parse(self, template))

        else
          Vedeu::Templating::Template.parse(self, template)

        end
      end

      # @return [String]
      def html_body
        out = ''
        Array(content).each do |line|
          out << "#{start_row_tag}\n"
          line.each do |char|
            if char.is_a?(Vedeu::Char)
              out << char.to_html
              out << "\n"
            end
          end
          out << "#{end_row_tag}\n"
        end
        out
      end

      private

      # @return [Array<Array<Vedeu::Char>>]
      def content
        options[:content]
      end

      # @return [String]
      def end_row_tag
        options[:end_row_tag]
      end

      # @return [String]
      def start_row_tag
        options[:start_row_tag]
      end

      # @return [String]
      def template
        options[:template]
      end

      # Combines the options provided at instantiation with the default values.
      #
      # @return [Hash<Symbol => void>]
      def options
        defaults.merge!(@options)
      end

      # The default values for a new instance of this class.
      #
      # @return [Hash<Symbol => void>]
      def defaults
        {
          content:       '',
          end_row_tag:   '</tr>',
          start_row_tag: '<tr>',
          template:      default_template,
        }
      end

      # @return [String]
      def default_template
        ::File.dirname(__FILE__) + '/../templates/html_renderer.vedeu'
      end

    end # HTML

  end # Renderers

end # Vedeu