rails duplicate habtm 二重に多対多備忘録

　Hoges と Fugas が多対多の関係で欲しい場合は、habtm を使えばシンプルに済みます。しかし、この多対多の関係が、もうひとつ欲しい・・・となったとき、？？？？？かなり悩んだ

  create table hoges (
    id serial primary key,
    name varchar(16)
  );
  create table fugas (
    id serial primary key,
    name varchar(16)
  );
  create table fugas_and_hoges (
    id serial primary key,
    fuga_id integer,
    hoge_id integer
  );
  create table another_fugas_and_hoges (
    id serial primary key,
    fuga_id integer,
    hoge_id integer
  );

このようなテーブルに対して

class FugasAndHoge < ActiveRecord::Base
  belongs_to :fuga
  belongs_to :hoge
end

class AnotherFugasAndHoge < ActiveRecord::Base
  belongs_to :fuga
  belongs_to :hoge
end

class Fuga < ActiveRecord::Base
  has_many :fugas_and_hoges, :dependent => :destroy
  has_many :hoges, :through => :fugas_and_hoges, :dependent => :destroy
  has_many :another_fugas_and_hoges, :dependent => :destroy
  has_many :another_hoges, :source => :hoge, :through => :another_fugas_and_hoges, :dependent => :destroy
end


class Hoge < ActiveRecord::Base
  has_many :fugas_and_hoges, :dependent => :destroy
  has_many :fugas, :through => :fugas_and_hoges, :dependent => :destroy
  has_many :another_fugas_and_hoges, :dependent => :destroy
  has_many :another_fugas, :source => :fuga, :through => :another_fugas_and_hoges, :dependent => :destroy
end

　うーむ・・・