module ReactOnRails::Helper

def server_rendered_react_component(render_options)
  return { "html" => "", "consoleReplayScript" => "" } unless render_options.prerender
  react_component_name = render_options.react_component_name
  props = render_options.props
  # On server `location` option is added (`location = request.fullpath`)
  # React Router needs this to match the current route
  # Make sure that we use up-to-date bundle file used for server rendering, which is defined
  # by config file value for config.server_bundle_js_file
  ReactOnRails::ServerRenderingPool.reset_pool_if_server_bundle_was_modified
  # Since this code is not inserted on a web page, we don't need to escape props
  #
  # However, as JSON (returned from `props_string(props)`) isn't JavaScript,
  # but we want treat it as such, we need to compensate for the difference.
  #
  # \u2028 and \u2029 are valid characters in strings in JSON, but are treated
  # as newline separators in JavaScript. As no newlines are allowed in
  # strings in JavaScript, this causes an exception.
  #
  # We fix this by replacing these unicode characters with their escaped versions.
  # This should be safe, as the only place they can appear is in strings anyway.
  #
  # Read more here: http://timelessrepo.com/json-isnt-a-javascript-subset
  js_code = ReactOnRails::ServerRenderingJsCode.server_rendering_component_js_code(
    props_string: props_string(props).gsub("\u2028", '\u2028').gsub("\u2029", '\u2029'),
    rails_context: rails_context(server_side: true).to_json,
    redux_stores: initialize_redux_stores(render_options),
    react_component_name: react_component_name,
    render_options: render_options
  )
  begin
    result = ReactOnRails::ServerRenderingPool.server_render_js_with_console_logging(js_code, render_options)
  rescue StandardError => err
    # This error came from the renderer
    raise ReactOnRails::PrerenderError.new(component_name: react_component_name,
                                           # Sanitize as this might be browser logged
                                           props: sanitized_props_string(props),
                                           err: err,
                                           js_code: js_code)
  end
  if render_options.streaming?
    result.transform do |chunk_json_result|
      if should_raise_streaming_prerender_error?(chunk_json_result, render_options)
        raise_prerender_error(chunk_json_result, react_component_name, props, js_code)
      end
      # It doesn't make any transformation, it listens and raises error if a chunk has errors
      chunk_json_result
    end
    result.rescue do |err|
      # This error came from the renderer
      raise ReactOnRails::PrerenderError.new(component_name: react_component_name,
                                             # Sanitize as this might be browser logged
                                             props: sanitized_props_string(props),
                                             err: err,
                                             js_code: js_code)
    end
  elsif result["hasErrors"] && render_options.raise_on_prerender_error
    raise_prerender_error(result, react_component_name, props, js_code)
  end
  result
end