store supervoter scores in post vote score

app/models/post_vote.rb

@@ -4,8 +4,9 @@ class PostVote < ActiveRecord::Base
   belongs_to :post
   before_validation :initialize_user, :on => :create
   validates_presence_of :post_id, :user_id, :score
-  validates_inclusion_of :score, :in => [1, -1]
+  validates_inclusion_of :score, :in => [SuperVoter::MAGNITUDE, 1, -1, -SuperVoter::MAGNITUDE]
   attr_accessible :post_id, :user_id, :score
+  after_destroy :update_post_on_destroy
 
   def self.prune!
     where("created_at < ?", 30.days.ago).delete_all
@@ -13,13 +14,31 @@ class PostVote < ActiveRecord::Base
 
   def score=(x)
     if x == "up"
-      write_attribute(:score, 1)
+      Post.where(:id => post_id).update_all("score = score + #{magnitude}, up_score = up_score + #{magnitude}")
+      write_attribute(:score, magnitude)
     elsif x == "down"
-      write_attribute(:score, -1)
+      Post.where(:id => post_id).update_all("score = score - #{magnitude}, down_score = down_score - #{magnitude}")
+      write_attribute(:score, -magnitude)
     end
   end
 
   def initialize_user
     self.user_id = CurrentUser.user.id
   end
+
+  def update_post_on_destroy
+    if score > 0
+      Post.where(:id => post_id).update_all("score = score - #{score}, up_score = up_score - #{score}")
+    else
+      Post.where(:id => post_id).update_all("score = score - #{score}, down_score = down_score - #{score}")
+    end
+  end
+
+  def magnitude
+    if CurrentUser.is_super_voter?
+      SuperVoter::MAGNITUDE
+    else
+      1
+    end
+  end
 end