Clean up the controller

app/models/card/messages.rb

@@ -3,9 +3,15 @@ module Card::Messages
 
   included do
     has_many :messages, -> { chronologically }, dependent: :destroy
+    has_many :comments, through: :messages, source: :messageable
     after_save :capture_draft_comment
   end
 
+  def comments
+    # FIXME: I could have sworn there was a way to declare this as a association?
+    Comment.joins(:message).where(messages: { card_id: id })
+  end
+
   def capture(messageable)
     messages.create! messageable: messageable
   end