Fix run and score statistics for internal and external users

app/controllers/exercises_controller.rb

@@ -496,7 +496,7 @@ working_time_accumulated: working_time_accumulated})
       render 'exercises/external_users/statistics'
     else
       # Show general statistic page for specific exercise
-      user_statistics = {}
+      user_statistics = {'InternalUser' => {}, 'ExternalUser' => {}}
       additional_filter = if policy(@exercise).detailed_statistics?
                             ''
                           elsif !policy(@exercise).detailed_statistics? && current_user.study_groups.count.positive?
@@ -505,11 +505,11 @@ working_time_accumulated: working_time_accumulated})
                             # e.g. internal user without any study groups, show no submissions
                             'AND FALSE'
                           end
-      query = "SELECT user_id, MAX(score) AS maximum_score, COUNT(id) AS runs
+      query = "SELECT user_id, user_type, MAX(score) AS maximum_score, COUNT(id) AS runs
-              FROM submissions WHERE exercise_id = #{@exercise.id} #{additional_filter} AND user_type = 'ExternalUser'
+              FROM submissions WHERE exercise_id = #{@exercise.id} #{additional_filter}
-              GROUP BY user_id;"
+              GROUP BY user_id, user_type;"
       ApplicationRecord.connection.execute(query).each do |tuple|
-        user_statistics[tuple['user_id'].to_i] = tuple
+        user_statistics[tuple['user_type']][tuple['user_id'].to_i] = tuple
       end
       render locals: {
         user_statistics: user_statistics,

app/views/exercises/statistics.html.slim

@@ -73,7 +73,7 @@ h1 = @exercise
         tbody
           - users = symbol.to_s.classify.constantize.where(id: submissions.joins(symbol).group(:user_id).select(:user_id).distinct)
           - users.each do |user|
-            - if user_statistics[user.id] then us = user_statistics[user.id] else us = {"maximum_score" => nil, "runs" => nil}
+            - if user_statistics[user.class.name][user.id] then us = user_statistics[user.class.name][user.id] else us = {"maximum_score" => nil, "runs" => nil}
             - label = "#{user.displayname}"
             tr
               td = link_to_if symbol==:external_users && policy(user).statistics?, label, {controller: "exercises", action: "statistics", external_user_id: user.id, id: @exercise.id}