blog_post.rb

        require 'acts-as-taggable-on'
        require 'seo_meta'

        class BlogPost < ActiveRecord::Base

          is_seo_meta if self.table_exists?

          default_scope :order => 'published_at DESC'
          #.first & .last will be reversed -- consider a with_exclusive_scope on these?

          belongs_to :author, :class_name => 'User', :foreign_key => :user_id

          has_many :comments, :class_name => 'BlogComment', :dependent => :destroy
          acts_as_taggable

          has_many :categorizations
          has_many :categories, :through => :categorizations, :source => :blog_category

          acts_as_indexed :fields => [:title, :body]

          validates :title, :presence => true, :uniqueness => true
          validates :body,  :presence => true
          validates :link_url, :presence => { :message => "must have a link_url if is_link is true" } if :is_link

          has_friendly_id :friendly_id_source, :use_slug => true,
                          :default_locale => (::Refinery::I18n.default_frontend_locale rescue :en),
                          :approximate_ascii => RefinerySetting.find_or_set(:approximate_ascii, false, :scoping => 'blog'),
                          :strip_non_ascii => RefinerySetting.find_or_set(:strip_non_ascii, false, :scoping => 'blog')

          attr_accessible :title, :body, :tag_list, :draft, :published_at, :browser_title, :meta_keywords, :meta_description, :user_id, :category_ids, :custom_url, :custom_teaser, :is_link, :link_url

          scope :by_archive, lambda { |archive_date|
            where(['published_at between ? and ?', archive_date.beginning_of_month, archive_date.end_of_month])
          }

          scope :by_year, lambda { |archive_year|
            where(['published_at between ? and ?', archive_year.beginning_of_year, archive_year.end_of_year])
          }

          scope :all_previous, lambda { where(['published_at <= ?', Time.now.beginning_of_month]) }

          scope :live, lambda { where( "published_at <= ? and draft = ?", Time.now, false) }

          scope :previous, lambda { |i| where(["published_at < ? and draft = ?", i.published_at, false]).limit(1) }
          # next is now in << self

          def next
            BlogPost.next(self).first
          end

          def prev
            BlogPost.previous(self).first
          end

          def live?
            !draft and published_at <= Time.now
          end

          def category_ids=(ids)
            self.categories = ids.reject{|id| id.blank?}.collect {|c_id|
              BlogCategory.find(c_id.to_i) rescue nil
            }.compact
          end

          def friendly_id_source
            custom_url.present? ? custom_url : title
          end

          class << self
            def next current_record
              self.send(:with_exclusive_scope) do
                where(["published_at > ? and draft = ?", current_record.published_at, false]).order("published_at ASC")
              end
            end

            def comments_allowed?
              RefinerySetting.find_or_set(:comments_allowed, true, {
                :scoping => 'blog'
              })
            end

            def uncategorized
              BlogPost.live.reject { |p| p.categories.any? }
            end
          end

          module ShareThis
            DEFAULT_KEY = "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"

            class << self
              def key
                RefinerySetting.find_or_set(:share_this_key, BlogPost::ShareThis::DEFAULT_KEY, {
                  :scoping => 'blog'
                })
              end

              def enabled?
                key = BlogPost::ShareThis.key
                key.present? and key != BlogPost::ShareThis::DEFAULT_KEY
              end
            end
          end

        end