orbit-4-1/app/models/page.rb

class Page
   include MongoMapper::Document
  
   key :name, String
   key :parent_page_id, String
   
   key :content_en, String
   key :content_zh_tw, String
    
   key :layout_id, String
   key :layout_name, String
   key :use_engine, String
   key :external_link, String
   key :position, Integer
   key :is_published, Boolean
   
   belongs_to :layout
   has_many :children, :class_name => 'Page', :foreign_key => 'parent_page_id'
   
   validates_presence_of :name
   validates_presence_of :position
   
   before_save :setup_layout_id
   before_validation :setup_default_value
  
   def self.find_by_name(page_name)
     Page.find(:first, :conditions => { :name => page_name, :is_published => true })
   end
   
   protected
      
   def setup_layout_id
     if self.layout_name.blank?
       self.layout_id = nil
     else
       self.layout_id = Layout.find_by_name( self.layout_name ).id
     end
   end
   
   def setup_default_value
     if self.position.blank?
       max_page = Page.find(:last, :order => 'position')
       self.position = (max_page)? max_page.position.to_i + 1 : 1
     end
     
     if self.parent_page_id.blank?
       self.parent_page_id = "root"
     end
   end
    
end