Merge remote-tracking branch 'origin/master' into exercise-anomaly-detection

# Conflicts:
#	db/schema.rb

app/models/exercise.rb

@@ -37,6 +37,8 @@ class Exercise < ActiveRecord::Base
 
   @working_time_statistics = nil
 
+  MAX_EXERCISE_FEEDBACKS = 20
+
 
   def average_percentage
     if average_score and maximum_score != 0.0 and submissions.exists?(cause: 'submit')
@@ -362,4 +364,8 @@ class Exercise < ActiveRecord::Base
   end
   private :valid_main_file?
 
+  def needs_more_feedback?
+    user_exercise_feedbacks.size <= MAX_EXERCISE_FEEDBACKS
+  end
+
 end

app/models/submission.rb

@@ -18,6 +18,8 @@ class Submission < ActiveRecord::Base
   validates :cause, inclusion: {in: CAUSES}
   validates :exercise_id, presence: true
 
+  MAX_COMMENTS_ON_RECOMMENDED_RFC = 5
+
   def build_files_hash(files, attribute)
     files.map(&attribute.to_proc).zip(files).to_h
   end
@@ -53,4 +55,16 @@ class Submission < ActiveRecord::Base
   def to_s
     Submission.model_name.human
   end
+
+  def redirect_to_feedback?
+    ((user_id + exercise.created_at.to_i) % 10 == 1) && exercise.needs_more_feedback?
+  end
+
+  def own_unsolved_rfc
+    RequestForComment.unsolved.where(exercise_id: exercise, user_id: user_id).first
+  end
+
+  def unsolved_rfc
+    RequestForComment.unsolved.where(exercise_id: exercise).where.not(question: nil).order("RANDOM()").find { | rfc_element |(rfc_element.comments_count < MAX_COMMENTS_ON_RECOMMENDED_RFC) }
+  end
 end

app/models/user_exercise_feedback.rb

@@ -2,10 +2,11 @@ class UserExerciseFeedback < ActiveRecord::Base
   include Creation
 
   belongs_to :exercise
+  has_one :execution_environment, through: :exercise
 
   validates :user_id, uniqueness: { scope: [:exercise_id, :user_type] }
 
   def to_s
     "User Exercise Feedback"
   end
-end
+end