class Book < ActiveRecord::Base
  has_many :authors, :dependent => true
  has_many :pages, :dependent => true
  has_many :entry_versions, :order => "entry_versions.created_at DESC"
  
  after_create :create_home_page

  def find_or_build_page(title)
    pages.find_by_title(title) || pages.build(:title => title)
  end
  
  def find_or_create_page(attributes)
    pages.find_by_title(attributes[:title]) || pages.create(attributes)
  end

  def find_or_create_author(name, ip)
    authors.find_by_name_and_ip(name, ip) || authors.create(:name => name, :ip => ip)
  end
  
  def to_param
    url_name
  end

  def existing_page_titles
    connection.select_all("SELECT title FROM pages WHERE book_id = #{self.id.to_i}").map { |row| row['title'] }
  end

  protected
    
    def create_home_page
      page    = pages.create(:title => "Home Page")
      version = page.entry_versions.build(:body => "Welcome to i2!")
      author  = version.create_author(:name => "i2", :ip => "127.0.0.1", :book => self)
      version.save!
    end
end