From 9058ce00dbda2d1fda4cc94ac2ca3719a6dab983 Mon Sep 17 00:00:00 2001
From: Sebastian Serth <Sebastian.Serth@hpi.de>
Date: Sun, 14 Nov 2021 17:05:13 +0100
Subject: [PATCH] Add A/B/n test for interventions

---
 app/controllers/exercises_controller.rb | 18 +++++++++++--
 lib/java21_study.rb                     | 33 +++++++++++++++++++++++
 lib/user_group_separator.rb             | 35 +++++++++++++++++++++++++
 3 files changed, 84 insertions(+), 2 deletions(-)
 create mode 100644 lib/java21_study.rb
 create mode 100644 lib/user_group_separator.rb

diff --git a/app/controllers/exercises_controller.rb b/app/controllers/exercises_controller.rb
index e5c28827..5b129bc8 100644
--- a/app/controllers/exercises_controller.rb
+++ b/app/controllers/exercises_controller.rb
@@ -296,10 +296,24 @@ raise: false
 
     if @embed_options[:disable_interventions]
       @show_rfc_interventions = false
+      @show_break_interventions = false
+      @show_tips_interventions = false
     else
-      @show_rfc_interventions = (!user_solved_exercise && !user_got_enough_interventions).to_s
+      show_intervention = (!user_solved_exercise && !user_got_enough_interventions).to_s
+      if @tips.present? && Java21Study.show_tips_intervention?(current_user, @exercise)
+        @show_tips_interventions = show_intervention
+        @show_break_interventions = false
+        @show_rfc_interventions = false
+      elsif Java21Study.show_break_intervention?(current_user, @exercise)
+        @show_tips_interventions = false
+        @show_break_interventions = show_intervention
+        @show_rfc_interventions = false
+      else
+        @show_tips_interventions = false
+        @show_break_interventions = false
+        @show_rfc_interventions = show_intervention
+      end
     end
-    @show_break_interventions = false
 
     @hide_rfc_button = @embed_options[:disable_rfc]
 
diff --git a/lib/java21_study.rb b/lib/java21_study.rb
new file mode 100644
index 00000000..bf5340b8
--- /dev/null
+++ b/lib/java21_study.rb
@@ -0,0 +1,33 @@
+# frozen_string_literal: true
+
+class Java21Study
+  def self.get_for(exercise)
+    java21_collection = ExerciseCollection.find_by(name: 'java2021', id: 13)
+
+    exercise.exercise_collections.include? java21_collection
+  end
+
+  def self.show_tips_intervention?(user, exercise)
+    java21_exercise = get_for(exercise)
+    return false unless java21_exercise # Exercise is not part of the experiment
+
+    user_group = UserGroupSeparator.get_intervention_group(user.id)
+    user_group == :show_tips_intervention
+  end
+
+  def self.show_break_intervention?(user, exercise)
+    java21_exercise = get_for(exercise)
+    return false unless java21_exercise # Exercise is not part of the experiment
+
+    user_group = UserGroupSeparator.get_intervention_group(user.id)
+    user_group == :show_break_intervention
+  end
+
+  def self.allow_redirect_to_community_solution?(user, exercise)
+    java21_exercise = get_for(exercise)
+    return false unless java21_exercise # Exercise is not part of the experiment
+
+    user_group = UserGroupSeparator.get_community_solution_group(user.id)
+    user_group == :show_community_solution
+  end
+end
diff --git a/lib/user_group_separator.rb b/lib/user_group_separator.rb
new file mode 100644
index 00000000..25634d04
--- /dev/null
+++ b/lib/user_group_separator.rb
@@ -0,0 +1,35 @@
+# frozen_string_literal: true
+
+class UserGroupSeparator
+  # Different user groups for the Java21 course based on the user_id
+  # 0: show_tips_intervention && no_b
+  # 1: show_break_intervention && no_b
+  # 2: show_rfc_intervention && no_b
+  # 3: show_tips_intervention && show_b
+  # 4: show_break_intervention && show_b
+  # 5: show_rfc_intervention && show_b
+
+  # separates user into 33% tips interventions, 33% break intervention, 33% rfc intervention
+  def self.get_intervention_group(user_id)
+    user_group = user_id % 6 # => 0, 1, 2, 3, 4, 5
+    case user_group
+      when 0, 3
+        :show_tips_intervention
+      when 1, 4
+        :show_break_intervention
+      else # 2, 5
+        :show_rfc_intervention
+    end
+  end
+
+  # separates user into 50% with Community Solution, 50% without Community Solution
+  def self.get_community_solution_group(user_id)
+    user_group = user_id % 6 # => 0, 1, 2, 3, 4, 5
+    case user_group
+      when 0, 1, 2
+        :show_community_solution
+      else # 3, 4, 5
+        :no_community_solution
+    end
+  end
+end