module Spina
  module Embeds
    module TrixConversion
      extend ActiveSupport::Concern

      # Wrap rendered partial in an <embed> tag for Trix
      def to_trix_attachment(content = trix_attachment_content)
        wrap_with_embed_tag(content)
      end

      def wrap_with_embed_tag(html)
        element = html_document.create_element("spina-embed", embed_tag_attributes)
        element.inner_html = html
        element.to_html
      end

      private

      def embed_tag_attributes
        spina_attributes.merge({"data-embed-attributes": embed_attributes_to_json})
      end

      def embed_attributes_to_json
        JSON.generate self.class.embed_attributes.map { |a| [a.to_s, send(a)] }.to_h
      end

      def spina_attributes
        {"data-embed-type": self.class.name, "data-controller": "embed-tag"}
      end

      def trix_attachment_content
        ApplicationController.render(partial: to_trix_partial_path, formats: :html, object: self, as: model_name.element)
      end

      def html_document
        Nokogiri::HTML::Document.new.tap { |doc| doc.encoding = "UTF-8" }
      end
    end
  end
end