1 files changed, 103 insertions, 0 deletions
diff --git a/actiontext/lib/action_text/attachment.rb b/actiontext/lib/action_text/attachment.rb
new file mode 100644
index 0000000000..e90a3e7d48
--- /dev/null
+++ b/actiontext/lib/action_text/attachment.rb
@@ -0,0 +1,103 @@
+# frozen_string_literal: true
+
+module ActionText
+  class Attachment
+    include Attachments::TrixConversion, Attachments::Minification, Attachments::Caching
+
+    TAG_NAME = "action-text-attachment"
+    SELECTOR = TAG_NAME
+    ATTRIBUTES = %w( sgid content-type url href filename filesize width height previewable presentation caption )
+
+    class << self
+      def fragment_by_canonicalizing_attachments(content)
+        fragment_by_minifying_attachments(fragment_by_converting_trix_attachments(content))
+      end
+
+      def from_node(node, attachable = nil)
+        new(node, attachable || ActionText::Attachable.from_node(node))
+      end
+
+      def from_attachables(attachables)
+        Array(attachables).map { |attachable| from_attachable(attachable) }.compact
+      end
+
+      def from_attachable(attachable, attributes = {})
+        if node = node_from_attributes(attachable.to_rich_text_attributes(attributes))
+          new(node, attachable)
+        end
+      end
+
+      def from_attributes(attributes, attachable = nil)
+        if node = node_from_attributes(attributes)
+          from_node(node, attachable)
+        end
+      end
+
+      private
+        def node_from_attributes(attributes)
+          if attributes = process_attributes(attributes).presence
+            ActionText::HtmlConversion.create_element(TAG_NAME, attributes)
+          end
+        end
+
+        def process_attributes(attributes)
+          attributes.transform_keys { |key| key.to_s.underscore.dasherize }.slice(*ATTRIBUTES)
+        end
+    end
+
+    attr_reader :node, :attachable
+
+    delegate :to_param, to: :attachable
+    delegate_missing_to :attachable
+
+    def initialize(node, attachable)
+      @node = node
+      @attachable = attachable
+    end
+
+    def caption
+      node_attributes["caption"].presence
+    end
+
+    def full_attributes
+      node_attributes.merge(attachable_attributes).merge(sgid_attributes)
+    end
+
+    def with_full_attributes
+      self.class.from_attributes(full_attributes, attachable)
+    end
+
+    def to_plain_text
+      if respond_to?(:attachable_plain_text_representation)
+        attachable_plain_text_representation(caption)
+      else
+        caption.to_s
+      end
+    end
+
+    def to_html
+      HtmlConversion.node_to_html(node)
+    end
+
+    def to_s
+      to_html
+    end
+
+    def inspect
+      "#<#{self.class.name} attachable=#{attachable.inspect}>"
+    end
+
+    private
+      def node_attributes
+        @node_attributes ||= ATTRIBUTES.map { |name| [ name.underscore, node[name] ] }.to_h.compact
+      end
+
+      def attachable_attributes
+        @attachable_attributes ||= (attachable.try(:to_rich_text_attributes) || {}).stringify_keys
+      end
+
+      def sgid_attributes
+        @sgid_attributes ||= node_attributes.slice("sgid").presence || attachable_attributes.slice("sgid")
+      end
+  end
+end