added popular exploration, added order:rank

app/logical/post_sets/popular.rb

@@ -0,0 +1,48 @@
+module PostSets
+  class Popular < Base
+    attr_reader :date, :scale
+    
+    def initialize(date, scale)
+      @date = date.blank? ? Date.today : date.to_date
+      @scale = scale
+    end
+    
+    def posts
+      ::Post.where("created_at between ? and ?", min_date, max_date + 1).order("score desc").limit(limit)
+    end
+    
+    def limit
+      25
+    end
+    
+    def min_date
+      case scale
+      when "week"
+        date.beginning_of_week
+        
+      when "month"
+        date.beginning_of_month
+        
+      else
+        date
+      end
+    end
+    
+    def max_date
+      case scale
+      when "week"
+        date.end_of_week
+        
+      when "month"
+        date.end_of_month
+        
+      else
+        date
+      end
+    end
+
+    def presenter
+      ::PostSetPresenters::Popular.new(self)
+    end
+  end
+end