added whenever (cron replacement), fixed related tag calculation updates (now delayed), tag subscriptions now calculated on cron

app/models/post.rb

@@ -488,16 +488,20 @@ class Post < ActiveRecord::Base
     
     def add_tag_subscription_relation(subscriptions, relation)
       subscriptions.each do |subscription|
-        subscription =~ /^(.+?):(.+)$/
-        user_name = $1 || subscription
-        subscription_name = $2
-
-        user = User.find_by_name(user_name)
-
-        if user
+        if subscription =~ /^(.+?):(.+)$/
+          user_name = $1
+          subscription_name = $2
+          user = User.find_by_name(user_name)
+          return relation if user.nil?
           post_ids = TagSubscription.find_post_ids(user.id, subscription_name)
-          relation = relation.where(["posts.id IN (?)", post_ids])
+        else
+          user = User.find_by_name(subscription)
+          return relation if user.nil?
+          post_ids = TagSubscription.find_post_ids(user.id)
         end
+        
+        post_ids = [0] if post_ids.empty?
+        relation = relation.where(["posts.id IN (?)", post_ids])
       end
       
       relation

app/models/tag.rb

@@ -310,11 +310,11 @@ class Tag < ActiveRecord::Base
   module RelationMethods
     def update_related
       counts = RelatedTagCalculator.calculate_from_sample(Danbooru.config.post_sample_size, name)
-      self.related_tags = RelatedTagCalculator.convert_hash_to_string(counts)
+      update_attributes(:related_tags => RelatedTagCalculator.convert_hash_to_string(counts), :related_tags_updated_at => Time.now)
     end
     
     def update_related_if_outdated
-      updated_related if should_update_related?
+      delay.update_related if should_update_related?
     end
     
     def related_cache_expiry