```ruby
require 'greenhorn/craft/base_model'

module Greenhorn
  module Craft
    class CategoryGroup < BaseModel
      include Craft::FieldBehaviors

      def self.table
        'categorygroups'
      end

      has_many :categories, foreign_key: 'groupId'
      has_many :group_locales, foreign_key: 'groupId', class_name: 'CategoryGroupLocale'
      belongs_to :structure, foreign_key: 'structureId'
      belongs_to :field_layout, foreign_key: 'fieldLayoutId'

      before_create do
        self.structure = Structure.create!
        self.field_layout = FieldLayout.create!(type: 'Category')
        self.handle = Utility::Handle.new(name)
      end

      after_create do
        root_element = StructureElement.create(structure: structure, lft: 1, rgt: 2, level: 0)
        root_element.update(root: root_element)

        group_locales = Locale.all.map { |locale| CategoryGroupLocale.new(locale: locale.locale) }
        update(group_locales: group_locales)
      end

      def initialize(attrs)
        attrs[:hasUrls] = false if attrs[:hasUrls].nil?
        super(attrs)
      end

      def locales
        group_locales.map(&:source_locale)
      end
    end
  end
end
```

Add support for ordering categories by their structure order
user
```ruby
require 'greenhorn/craft/base_model'

module Greenhorn
  module Craft
    class CategoryGroup < BaseModel
      include Craft::FieldBehaviors

      def self.table
        'categorygroups'
      end

      has_many :categories, foreign_key: 'groupId'
      has_many :group_locales, foreign_key: 'groupId', class_name: 'CategoryGroupLocale'
      belongs_to :structure, foreign_key: 'structureId'
      belongs_to :field_layout, foreign_key: 'fieldLayoutId'

      before_create do
        self.structure = Structure.create!
        self.field_layout = FieldLayout.create!(type: 'Category')
        self.handle = Utility::Handle.new(name)
      end

      after_create do
        root_element = StructureElement.create(structure: structure, lft: 1, rgt: 2, level: 0)
        root_element.update(root: root_element)

        group_locales = Locale.all.map { |locale| CategoryGroupLocale.new(locale: locale.locale) }
        update(group_locales: group_locales)
      end

      def ordered_categories
        categories.joins(:structure_element).order('craft_structureelements.lft')
      end

      def initialize(attrs)
        attrs[:hasUrls] = false if attrs[:hasUrls].nil?
        super(attrs)
      end

      def locales
        group_locales.map(&:source_locale)
      end
    end
  end
end
```
assistant