require 'models/topic' class Reply < Topic named_scope :base belongs_to :topic, :foreign_key => "parent_id", :counter_cache => true has_many :replies, :class_name => "SillyReply", :dependent => :destroy, :foreign_key => "parent_id" validate :errors_on_empty_content validate_on_create :title_is_wrong_create attr_accessible :title, :author_name, :author_email_address, :written_on, :content, :last_read def validate errors.add("title", "Empty") unless attribute_present? "title" end def errors_on_empty_content errors.add("content", "Empty") unless attribute_present? "content" end def validate_on_create if attribute_present?("title") && attribute_present?("content") && content == "Mismatch" errors.add("title", "is Content Mismatch") end end def title_is_wrong_create errors.add("title", "is Wrong Create") if attribute_present?("title") && title == "Wrong Create" end def validate_on_update errors.add("title", "is Wrong Update") if attribute_present?("title") && title == "Wrong Update" end end class SillyReply < Reply belongs_to :reply, :foreign_key => "parent_id", :counter_cache => :replies_count end