socialforge/app/models/org_message.rb

class OrgMessage < ActiveRecord::Base
  belongs_to :user
  belongs_to :organization
  has_many :message_alls, :class_name => 'MessageAll', :as => :message, :dependent => :destroy
  validates :message_type, :presence => true
  validates :message_id, :presence => true
  validates :organization_id, :presence => true
  after_create :add_user_message

  def add_user_message
    if MessageAll.where("message_type = '#{self.class.to_s}' and message_id = '#{self.id}'").first.nil?
      self.message_alls << MessageAll.new(:user_id => self.user_id)
    end
  end
end