class Jekyll::Tags::HighlightBlock

def add_code_tag(code)
  code_attributes = [
    "class=\"language-#{@lang.to_s.tr("+", "-")}\"",
    "data-lang=\"#{@lang}\""
  ].join(" ")
  "<figure class=\"highlight\"><pre><code #{code_attributes}>"\
  "#{code.chomp}</code></pre></figure>"
end

def initialize(tag_name, markup, tokens)
  super
  if markup.strip =~ SYNTAX
    @lang = Regexp.last_match(1).downcase
    @highlight_options = parse_options(Regexp.last_match(2))
  else
    raise SyntaxError, <<-eos
 Error in tag 'highlight' while parsing the following markup:
rkup}
syntax: highlight <lang> [linenos]
  end
end

def parse_options(input)
  options = {}
  unless input.empty?
    # Split along 3 possible forms -- key="<quoted list>", key=value, or key
    input.scan(%r!(?:\w="[^"]*"|\w=\w|\w)+!) do |opt|
      key, value = opt.split("=")
      # If a quoted list, convert to array
      if value && value.include?("\"")
        value.delete!('"')
        value = value.split
      end
      options[key.to_sym] = value || true
    end
  end
  if options.key?(:linenos) && options[:linenos] == true
    options[:linenos] = "inline"
  end
  options
end

def render(context)
  prefix = context["highlighter_prefix"] || ""
  suffix = context["highlighter_suffix"] || ""
  code = super.to_s.gsub(%r!\A(\n|\r)+|(\n|\r)+\z!, "")
  is_safe = !!context.registers[:site].safe
  output =
    case context.registers[:site].highlighter
    when "pygments"
      render_pygments(code, is_safe)
    when "rouge"
      render_rouge(code)
    else
      render_codehighlighter(code)
    end
  rendered_output = add_code_tag(output)
  prefix + rendered_output + suffix
end

def render_codehighlighter(code)
  h(code).strip
end

def render_pygments(code, is_safe)
  Jekyll::External.require_with_graceful_fail("pygments")
  highlighted_code = Pygments.highlight(
    code,
    :lexer   => @lang,
    :options => sanitized_opts(@highlight_options, is_safe)
  )
  if highlighted_code.nil?
    Jekyll.logger.error <<eos
was an error highlighting your code:
}
attempting to convert the above code, Pygments.rb returned an unacceptable value.
s usually a timeout problem solved by running `jekyll build` again.
    raise ArgumentError, "Pygments.rb returned an unacceptable value "\
    "when attempting to highlight some code."
  end
  highlighted_code.sub('<div class="highlight"><pre>', "").sub("</pre></div>", "")
end

def render_rouge(code)
  Jekyll::External.require_with_graceful_fail("rouge")
  formatter = Rouge::Formatters::HTML.new(
    :line_numbers => @highlight_options[:linenos],
    :wrap         => false
  )
  lexer = Rouge::Lexer.find_fancy(@lang, code) || Rouge::Lexers::PlainText
  formatter.format(lexer.lex(code))
end

def sanitized_opts(opts, is_safe)
  if is_safe
    Hash[[
      [:startinline, opts.fetch(:startinline, nil)],
      [:hl_lines,    opts.fetch(:hl_lines, nil)],
      [:linenos,     opts.fetch(:linenos, nil)],
      [:encoding,    opts.fetch(:encoding, "utf-8")],
      [:cssclass,    opts.fetch(:cssclass, nil)]
    ].reject { |f| f.last.nil? }]
  else
    opts
  end
end