class Middleman::PreviewServer

def start(opts={})
  # Do not buffer output, otherwise testing of output does not work
  $stdout.sync = true
  $stderr.sync = true
  @options = opts
  @server_information = ServerInformation.new
  @server_information.https = (@options[:https] == true)
  # New app evaluates the middleman configuration. Since this can be
  # invalid as well, we need to evaluate the configuration BEFORE
  # checking for validity
  the_app = initialize_new_app
  # And now comes the check
  unless server_information.valid?
    $stderr.puts %(== Running Middleman failed: #{server_information.reason}. Please fix that and try again.)
    exit 1
  end
  mount_instance(the_app)
  app.logger.debug %(== Server information is provided by #{server_information.handler})
  app.logger.debug %(== The Middleman is running in "#{environment}" environment)
  app.logger.debug format('== The Middleman preview server is bound to %s', ServerUrl.new(hosts: server_information.listeners, port: server_information.port, https: server_information.https?).to_bind_addresses.join(', '))
  app.logger.info format('== View your site at %s', ServerUrl.new(hosts: server_information.site_addresses, port: server_information.port, https: server_information.https?).to_urls.join(', '))
  app.logger.info format('== Inspect your site configuration at %s', ServerUrl.new(hosts: server_information.site_addresses, port: server_information.port, https: server_information.https?).to_config_urls.join(', '))
  @initialized ||= false
  return if @initialized
  @initialized = true
  register_signal_handlers
  # Save the last-used @options so it may be re-used when
  # reloading later on.
  ::Middleman::Profiling.report('server_start')
  app.execute_callbacks(:before_server, [ServerInformationCallbackProxy.new(server_information)])
  if @options[:daemon]
    # To output the child PID, let's make preview server a daemon by hand
    if child_pid = fork
      app.logger.info "== Middleman preview server is running in background with PID #{child_pid}"
      Process.detach child_pid
      exit 0
    else
      $stdout.reopen('/dev/null', 'w')
      $stderr.reopen('/dev/null', 'w')
      $stdin.reopen('/dev/null', 'r')
    end
  end
  loop do
    @webrick.start
    # $mm_shutdown is set by the signal handler
    if $mm_shutdown
      shutdown
      exit
    elsif $mm_reload
      $mm_reload = false
      reload
    end
  end
end