Collapse duplication in tag cloud model

app/models/stats/tag_cloud.rb

@@ -3,62 +3,47 @@
 module Stats
   class TagCloud
 
-    attr_reader :user, :cutoff,
-      :tags, :min, :divisor,
-      :tags_90days, :min_90days, :divisor_90days
-    def initialize(user, cutoff)
+    attr_reader :user, :cutoff, :levels,
+      :tags, :min, :divisor
+    def initialize(user, cutoff = nil)
       @user = user
       @cutoff = cutoff
+      @levels = 10
     end
 
     def compute
-      levels=10
-      # TODO: parameterize limit
-
-      # Get the tag cloud for all tags for actions
-      query = "SELECT tags.id, name, count(*) AS count"
-      query << " FROM taggings, tags, todos"
-      query << " WHERE tags.id = tag_id"
-      query << " AND taggings.taggable_id = todos.id"
-      query << " AND todos.user_id="+user.id.to_s+" "
-      query << " AND taggings.taggable_type='Todo' "
-      query << " GROUP BY tags.id, tags.name"
-      query << " ORDER BY count DESC, name"
-      query << " LIMIT 100"
-      @tags = Tag.find_by_sql(query).sort_by { |tag| tag.name.downcase }
-
+      @tags = top_tags
       max, @min = 0, 0
       @tags.each { |t|
         max = [t.count.to_i, max].max
         @min = [t.count.to_i, @min].min
       }
-
       @divisor = ((max - @min) / levels) + 1
+    end
 
-      # Get the tag cloud for all tags for actions
+    private
+
+    def top_tags
+      params = [sql, user.id]
+      params += [cutoff, cutoff] if cutoff
+      Tag.find_by_sql(params).sort_by { |tag| tag.name.downcase }
+    end
+
+    def sql
+      # TODO: parameterize limit
       query = "SELECT tags.id, tags.name AS name, count(*) AS count"
       query << " FROM taggings, tags, todos"
       query << " WHERE tags.id = tag_id"
       query << " AND todos.user_id=? "
       query << " AND taggings.taggable_type='Todo' "
       query << " AND taggings.taggable_id=todos.id "
-      query << " AND (todos.created_at > ? OR "
-      query << "      todos.completed_at > ?) "
+      if cutoff
+        query << " AND (todos.created_at > ? OR "
+        query << "      todos.completed_at > ?) "
+      end
       query << " GROUP BY tags.id, tags.name"
       query << " ORDER BY count DESC, name"
       query << " LIMIT 100"
-      @tags_90days = Tag.find_by_sql(
-        [query, user.id, cutoff, cutoff]
-      ).sort_by { |tag| tag.name.downcase }
-
-      max_90days, @min_90days = 0, 0
-      @tags_90days.each { |t|
-        max_90days = [t.count.to_i, max_90days].max
-        @min_90days = [t.count.to_i, @min_90days].min
-      }
-
-      @divisor_90days = ((max_90days - @min_90days) / levels) + 1
-
     end
 
   end