module Formol
  class Category < ActiveRecord::Base
    #Modules
    include RankedModel
    
    #Associations
    has_many  :forums,  :dependent  => :destroy,
                        :order      => 'formol_forums.position'
    
    #Validations
    validates :label, :presence   =>  true,
                      :length     =>  { :in             => 3..32,
                                        :allow_blank    => true },
                      :uniqueness =>  { :case_sensitive => false,
                                        :allow_blank    => true }
                    
    #Normalization
    normalize_attributes  :label,  :with => [:squish, :blank]
    
    #Sorting
    ranks :position
    
    #Scopes
    class << self
      # return categories conveniently ordered and eager-loaded for listing
      def ready_for_listing
        includes(:forums => { :last_post => [:user, :topic] }).rank(:position)
      end
    end
    
    #Business
    class << self
      # Sorts categories from an array of ids
      def sort(category_ids)
        #TODO: should maybe optimize this?
        (category_ids || []).each_with_index do |category_id, index|
          find(category_id).update_attribute(:position, index)
        end
      end
    end
  end
end