convert ulysses markdown to bbcode

u2b.rb

# convert ulysses markdown to bbcode
class Main
  $code_buffer = []
  $is_code_sec = false

  def flush_code_buffer
    $code_buffer.each do |line|
      puts line
    end
    puts '[/code]'
    $code_buffer = []
    $is_code_sec = false
  end

  def convert
    File.open('xxx.txt').each do |line|
      if line[0] == '#'
        if line[1] == '#'
          print line.gsub(/^#*\s*(.*)\s*/, '[size=xx-large]\1[/size]')
        else
          print line.gsub(/^#*\s*(.*)\s*/, '[size=large]\1[/size]')
        end
        next
      elsif line[0] == "'" && line[1] == "'"
        if $is_code_sec == false
          $code_buffer << '[code]'
          $is_code_sec = true
        end

        $code_buffer << line.gsub(/'+\s*(.*)\s*/, '\1')
        next
      else
        flush_code_buffer if $is_code_sec == true
        print line
        next
      end
    end
  end
end

main = Main.new
main.convert