require 'coderay'
class SnippetParser
  include Reloadable
  def initialize(text)
    @text = text.to_s
  end

  def snippets
    build_snippets if @snippets.nil?
    @snippets
  end

  # wraps snippets in 

  def pre_format
    build_snippets do |tag, code|
      %(
#{code}
)
    end
  end

  def highlight(default_language = :ruby)
    build_snippets do |tag, code|
      CodeRay.scan(code, (tag && tag['attributes']) || default_language).html
    end
  end

  protected
    def build_snippets(&block)
      @snippets = []
      contents  = []
      tag       = nil
      returning [] do |output|
        tokenizer = HTML::Tokenizer.new(@text.to_s)

        while token = tokenizer.next
          node = HTML::Node.parse(nil, 0, 0, token, false)
          if node.tag? && node.name == 'code'
            if contents.blank? # open tag
              tag = node.dup
            else # closing tag
              output << close_snippet(tag, contents.join, &block) 
            end
            contents.clear
          else # inside a code tag
            contents << node.to_s
          end
        end

        # get any unfinished code blocks
        output << close_snippet(nil, contents.join, &block) unless contents.empty?
      end.join
    end

    def close_snippet(tag, contents, &block)
      @snippets << contents
      block ? block.call(tag, contents) : %(#{contents})
    end
end