module NotificationsHelper
  def notification_count
    if current_user.present?
      current_user.active_unread_notifications.count
    else
      Notification.active_unauthenticated_notifications.count
    end
  end

  def notification
    if current_user.present?
      current_user.newest_active_unread_notification
    else
      Notification.newest_active_unauthenticated_notification
    end
  end

  def render_for_banner(title)
    @@banner_renderer ||= NotificationTitleRenderer.new({ invert_link_colour: true, bold_all_text: true })
    @@banner_markdown ||= Redcarpet::Markdown.new(@@banner_renderer, no_intra_emphasis: true)
    @@banner_markdown.render(title)
  end

  def render_for_summary(title)
    @@plain_title_renderer ||= NotificationTitleRenderer.new({ invert_link_colour: false, bold_all_text: false })
    @@plain_title_markdown ||= Redcarpet::Markdown.new(@@plain_title_renderer, no_intra_emphasis: true)
    @@plain_title_markdown.render(title)
  end

private

  class NotificationTitleRenderer < Redcarpet::Render::HTML
    def initialize(options = {})
      link_class = "govuk-link"
      link_class += " govuk-link--inverse" if options[:invert_link_colour]
      @bold = options[:bold_all_text]
      base_options = { escape_html: true, safe_links_only: true, link_attributes: { class: link_class } }
      super base_options
    end

    def paragraph(text)
      return %(<p class="govuk-!-font-weight-bold">#{text}</p>) if @bold

      %(<p>#{text}</p>)
    end
  end
end