Move public_author into module

app/models/comment.rb

@@ -1,5 +1,6 @@
 class Comment < ActiveRecord::Base
   include Flaggable
+  include HasPublicAuthor
 
   acts_as_paranoid column: :hidden_at
   include ActsAsParanoidAliases
@@ -16,7 +17,6 @@ class Comment < ActiveRecord::Base
 
   belongs_to :commentable, -> { with_hidden }, polymorphic: true, counter_cache: true
   belongs_to :user, -> { with_hidden }
-  belongs_to :public_author, -> { with_public_activity }, class_name: 'User', foreign_key: 'user_id'
 
   before_save :calculate_confidence_score
 

app/models/concerns/has_public_author.rb

@@ -0,0 +1,5 @@
+module HasPublicAuthor
+  def public_author
+    self.author.public_activity? ? self.author : nil
+  end
+end

app/models/debate.rb

@@ -7,13 +7,13 @@ class Debate < ActiveRecord::Base
   include Sanitizable
   include Searchable
   include Filterable
+  include HasPublicAuthor
 
   acts_as_votable
   acts_as_paranoid column: :hidden_at
   include ActsAsParanoidAliases
 
   belongs_to :author, -> { with_hidden }, class_name: 'User', foreign_key: 'author_id'
-  belongs_to :public_author, -> { with_public_activity }, class_name: 'User', foreign_key: 'author_id'
   belongs_to :geozone
   has_many :comments, as: :commentable
 

app/models/proposal.rb

@@ -6,6 +6,7 @@ class Proposal < ActiveRecord::Base
   include Sanitizable
   include Searchable
   include Filterable
+  include HasPublicAuthor
 
   acts_as_votable
   acts_as_paranoid column: :hidden_at
@@ -14,7 +15,6 @@ class Proposal < ActiveRecord::Base
   RETIRE_OPTIONS = %w(duplicated started unfeasible done other)
 
   belongs_to :author, -> { with_hidden }, class_name: 'User', foreign_key: 'author_id'
-  belongs_to :public_author, -> { with_public_activity }, class_name: 'User', foreign_key: 'author_id'
   belongs_to :geozone
   has_many :comments, as: :commentable
   has_many :proposal_notifications