Add field_for_person methods

app/models/form/sales/pages/person.rb

@@ -15,4 +15,8 @@ class Form::Sales::Pages::Person < ::Form::Page
   def details_known_question_id
     "details_known_#{person_display_number}"
   end
+
+  def field_for_person(field, suffix = "")
+    [field, @person_index, suffix].join
+  end
 end

app/models/form/sales/pages/person_age.rb

@@ -9,21 +9,10 @@ class Form::Sales::Pages::PersonAge < Form::Sales::Pages::Person
     ]
   end
 
-  PERSON_INDEX = {
-    "person_1_age" => 2,
-    "person_2_age" => 3,
-    "person_3_age" => 4,
-    "person_4_age" => 5,
-    "person_1_age_joint_purchase" => 3,
-    "person_2_age_joint_purchase" => 4,
-    "person_3_age_joint_purchase" => 5,
-    "person_4_age_joint_purchase" => 6,
-  }.freeze
-
   def questions
     @questions ||= [
-      Form::Sales::Questions::PersonAgeKnown.new("age#{@person_index}_known", nil, self, person_index: @person_index),
-      Form::Sales::Questions::PersonAge.new("age#{@person_index}", nil, self, person_index: @person_index),
+      Form::Sales::Questions::PersonAgeKnown.new(field_for_person("age", "_known"), nil, self, person_index: @person_index),
+      Form::Sales::Questions::PersonAge.new(field_for_person("age"), nil, self, person_index: @person_index),
     ]
   end
 end

app/models/form/sales/pages/person_working_situation.rb

@@ -11,7 +11,7 @@ class Form::Sales::Pages::PersonWorkingSituation < Form::Sales::Pages::Person
 
   def questions
     @questions ||= [
-      Form::Sales::Questions::PersonWorkingSituation.new("ecstat#{@person_index}", nil, self, person_index: @person_index),
+      Form::Sales::Questions::PersonWorkingSituation.new(field_for_person("ecstat"), nil, self, person_index: @person_index),
     ]
   end
 end

app/models/form/sales/questions/person.rb

@@ -11,4 +11,8 @@ class Form::Sales::Questions::Person < ::Form::Question
   def joint_purchase?
     page.id.include?("_joint_purchase")
   end
+
+  def field_for_person(field, suffix = "")
+    [field, @person_index, suffix].join
+  end
 end

app/models/form/sales/questions/person_age.rb

@@ -7,7 +7,7 @@ class Form::Sales::Questions::PersonAge < Form::Sales::Questions::Person
     @page = page
     @width = 3
     @inferred_check_answers_value = {
-      "condition" => { "age#{person_index}_known" => 1 },
+      "condition" => { field_for_person("age", "_known") => 1 },
       "value" => "Not known",
     }
     @check_answers_card_number = person_index

app/models/form/sales/questions/person_age_known.rb

@@ -8,15 +8,15 @@ class Form::Sales::Questions::PersonAgeKnown < ::Form::Sales::Questions::Person
     @page = page
     @hint_text = ""
     @conditional_for = {
-      "age#{@person_index}" => [0],
+      field_for_person("age") => [0],
     }
     @hidden_in_check_answers = {
       "depends_on" => [
         {
-          "age#{@person_index}_known" => 0,
+          field_for_person("age", "_known") => 0,
         },
         {
-          "age#{@person_index}_known" => 1,
+          field_for_person("age", "_known") => 1,
         },
       ],
     }

app/models/form/sales/questions/person_working_situation.rb

@@ -22,12 +22,4 @@ class Form::Sales::Questions::PersonWorkingSituation < ::Form::Sales::Questions:
     "7" => { "value" => "Full-time student" },
     "9" => { "value" => "Child under 16" },
   }.freeze
-
-  PERSON_INDEX = {
-    "ecstat2" => 2,
-    "ecstat3" => 3,
-    "ecstat4" => 4,
-    "ecstat5" => 5,
-    "ecstat6" => 6,
-  }.freeze
 end