class Vote < ActiveRecord::Base belongs_to :photo belongs_to :user validate :unique_for_user validates_presence_of :photo_id attr_protected :user_id attr_protected :session_id ## # Checks if this vote is anonymous, or not an authenticated User vote. # def anonymous? self.user_id.nil? end ## # Convert this Vote to a number. # def to_i self.vote? ? 1 : 0 end ## # Is this a 'no' vote. # def zero? self.to_i == 0 end ## # Is this a 'yes' vote. # def one? self.to_i == 1 end ## # Checks if a user has voted for a Photo. If you pass a User for user it will # check for an authenticated user, else it will look for an anonymous vote. # def self.voted_for?(photo, user) c = [ 'photo_id = :pid' ] v = { :pid => (photo.respond_to?('id') ? photo.id : photo) } if user.respond_to?('id') c << 'user_id = :uid' v[:uid] = user.id else c << 'session_id = :uid' v[:uid] = user end self.find :first, :conditions => [ c.join(' AND '), v ] end ## # Does a quick find and collect on the cast votes so you can find a def self.voted_photo_ids(user) c = if user.respond_to?('id') "votes.user_id = #{user.id}" else "votes.session_id = '#{user}'" end self.find(:all, :conditions => c, :select => 'photo_id').collect { |v| v.photo_id } end protected def unique_for_user if self.user.to_s.empty? and self.session_id.empty? self.errors.add(:vote, 'must have an owner') elsif self.user and Vote.voted_for?(self.photo, self.user) self.errors.add(:vote, 'has already been collected for this photo') elsif self.session_id and Vote.voted_for?(self.photo, self.session_id) self.errors.add(:anonymous, 'vote has already been collected') end end end