Notes on changing a Many-to-Many to a Self-Referential Many-to-Many

gistfile1.txt

Currently I have Kits and Items. A Kit can contain many Items; an Item can be associated to many Kits.
I also have a join model, KitItem, that allows me to define how many of an Item is associated to a Kit.

Here are the model definitions:

class Kit < ActiveRecord::Base
  belongs_to :category
  has_many   :kit_items, :dependent => :destroy
  has_many   :items, :through => :kit_items
end

class Item < ActiveRecord::Base
  belongs_to :category
  has_many   :kit_items, :dependent => :destroy
  has_many   :kits, :through => :kit_items
end

class KitItem < ActiveRecord::Base
  belongs_to :item
  belongs_to :kit
end

# == Schema Information
#
# Table name: kit_items
#
#  id         :integer(4)      not null, primary key
#  quantity   :integer(4)
#  kit_id     :integer(4)
#  item_id    :integer(4)
#  created_at :datetime
#  updated_at :datetime
#
# Indexes
#
#  index_kit_items_on_item_id  (item_id)
#  index_kit_items_on_kit_id   (kit_id)
#

However, I need to support the concept of a Kit containing other Kits.

I'm not sure how to implement this. The examples I've seen so far are for single table self-joins; 
I've only confused myself when attempting to alter them for my purposes.

I'm definitely studying this less for the code and more for the magical incantation to summon @bokmann