topic.rb

topic.rb

# encoding: utf-8
class Topic < ActiveRecord::Base
  include Redis::Objects

  #Redis::Objects
  counter :hits #利用redis存储点击

  belongs_to :user
  belongs_to :node

  has_many :posts

  before_save :set_last_updated_at
  after_create :rest_posts_count

  accepts_nested_attributes_for :posts, :reject_if => lambda { |a| a[:body].blank? }, :allow_destroy => true

  scope :recent, order('last_updated_at DESC')

  def body
    return self.posts.major.first.body if self.posts.major.first
    ''
  end

  def last_reply
    Post.find(self.last_post_id) if self.last_post_id
  end

  def update_cached_post_fields(post)
    self.class.update_all(['last_post_id = ?', post.id], ['id = ?', id])
  end

  def set_last_updated_at
    self.last_updated_at = Time.now
  end

  def rest_posts_count
    self.class.update_all(['posts_count = ?', 0], ['id = ?', self.id])
  end
end