Set default "Untitled" title for published cards

app/models/card.rb

@@ -11,6 +11,8 @@ class Card < ApplicationRecord
 
   has_markdown :description
 
+  before_save :set_default_title
+
   scope :reverse_chronologically, -> { order created_at: :desc, id: :desc }
   scope :chronologically, -> { order created_at: :asc, id: :asc }
   scope :latest, -> { order updated_at: :desc, id: :desc }
@@ -25,11 +27,12 @@ class Card < ApplicationRecord
     end
   end
 
-  def title=(new_title)
-    self[:title] = new_title.presence || "Untitled"
-  end
-
   def cache_key
     [ super, collection.name ].compact.join("/")
   end
+
+  private
+    def set_default_title
+      self.title = "Untitled" if published? && title.blank?
+    end
 end

test/models/card_test.rb

@@ -120,4 +120,12 @@ class CardTest < ActiveSupport::TestCase
 
     assert_includes card.cache_key, ApplicationRecord.current_tenant, "cache key must always include the tenant"
   end
+
+  test "for published cards, it should set the default title 'Untitiled' when not provided" do
+    card = collections(:writebook).cards.create!
+    assert_nil card.title
+
+    card.publish
+    assert_equal "Untitled", card.reload.title
+  end
 end