class ChildTheme < ActiveRecord::Base belongs_to :parent_theme, class_name: 'Theme' belongs_to :child_theme, class_name: 'Theme' validate :child_validations private def child_validations if Theme.where( "(component IS true AND id = :parent) OR (component IS false AND id = :child)", parent: parent_theme_id, child: child_theme_id ).exists? errors.add(:base, I18n.t("themes.errors.no_multilevels_components")) end end end # == Schema Information # # Table name: child_themes # # id :integer not null, primary key # parent_theme_id :integer # child_theme_id :integer # created_at :datetime not null # updated_at :datetime not null # # Indexes # # index_child_themes_on_child_theme_id_and_parent_theme_id (child_theme_id,parent_theme_id) UNIQUE # index_child_themes_on_parent_theme_id_and_child_theme_id (parent_theme_id,child_theme_id) UNIQUE #