```ruby
class PostSearchResultSet
  attr_reader :site

  def initialize(groonga_posts:, site:, query:, page:)
    @groonga_posts = groonga_posts
    @site = site
    @query = query
    @page = page

    @snippet = nil
    @posts = nil
  end

  def keywords
    @query.keywords
  end

  def posts
    @posts ||= @site.posts
      .includes(:category, credits: [:participant])
      .published
      .where(id: paginated_post_ids)
      .order_as_specified(id: paginated_post_ids)
  end

  def paginator
    paginated_post_ids
  end

  def snippet(text, html_options = {})
    (@snippet ||= create_snippet(html_options)).execute(text)
  end

  private

  def searched_post_ids
    @groonga_posts.sort([['_score', :desc]]).map(&:_key)
  end

  def paginated_post_ids
    @paginated_post_ids ||= Kaminari.paginate_array(searched_post_ids).page(@page).per(50)
  end

  def create_snippet(html_options)
    open_tag = "<span class='#{html_options[:class]}'>"
    close_tag = "</span>"
    options = {
      normalize: true,
      width: 200,
      html_escape: true,
    }
    @groonga_posts.expression.snippet([open_tag, close_tag], options)
  end
end
```

Sort posts by score and published_at
user
```ruby
class PostSearchResultSet
  attr_reader :site

  def initialize(groonga_posts:, site:, query:, page:)
    @groonga_posts = groonga_posts
    @site = site
    @query = query
    @page = page

    @snippet = nil
    @posts = nil
  end

  def keywords
    @query.keywords
  end

  def posts
    @posts ||= @site.posts
      .includes(:category, credits: [:participant])
      .published
      .where(id: paginated_post_ids)
      .order_as_specified(id: paginated_post_ids)
  end

  def paginator
    paginated_post_ids
  end

  def snippet(text, html_options = {})
    (@snippet ||= create_snippet(html_options)).execute(text)
  end

  private

  def searched_post_ids
    @groonga_posts.sort([["_score", :desc], ["published_at", :desc]]).map(&:_key)
  end

  def paginated_post_ids
    @paginated_post_ids ||= Kaminari.paginate_array(searched_post_ids).page(@page).per(50)
  end

  def create_snippet(html_options)
    open_tag = "<span class='#{html_options[:class]}'>"
    close_tag = "</span>"
    options = {
      normalize: true,
      width: 200,
      html_escape: true,
    }
    @groonga_posts.expression.snippet([open_tag, close_tag], options)
  end
end
```
assistant