helpers do
  
  ##
  # Return dotted assertion graph for _assertions_.
  
  def assertion_graph_for assertions
    return if assertions.empty?
    assertions.map do |assertion|
      assertion['passed'] ? green('.') : red('.')
    end.join
  end
  
  ##
  # Override Sinatra's #send_file to prevent caching.
  
  def send_file path, opts = {}
    stat = File.stat(path)
    response['Cache-Control'] = 'no-cache'
    content_type media_type(opts[:type]) ||
      media_type(File.extname(path)) ||
      response['Content-Type'] ||
      'application/octet-stream'
    response['Content-Length'] ||= (opts[:length] || stat.size).to_s

    if opts[:disposition] == 'attachment' || opts[:filename]
      attachment opts[:filename] || path
    elsif opts[:disposition] == 'inline'
      response['Content-Disposition'] = 'inline'
    end

    halt ::Sinatra::Application::StaticFile.open(path, 'rb')
  rescue Errno::ENOENT
    not_found
  end
  
  ##
  # Find the browser name for the current user agent.
  
  def browser_name
    Browser.subclasses.find do |browser|
      browser.matches_agent? env['HTTP_USER_AGENT']
    end.new
  rescue
    'Unknown'
  end
  
  ##
  # Wrap _string_ with ansi escape sequence using _code_.
  
  def color string, code
    "\e[#{code}m#{string}\e[0m"
  end
  
  ##
  # Bold _string_.
  
  def bold string
    color string, 1
  end
  
  ##
  # Color _string_ red.
  
  def red string  
    color string, 31
  end
  
  ##
  # Color _string_ green.
  
  def green string
    color string, 32
  end
  
  ##
  # Color _string_ blue.
  
  def blue string
    color string, 34
  end
end