CST-2575: allow payment-frozen participants to be transferred back to…

… their original cohort

app/services/induction/amend_participant_cohort.rb

@@ -22,7 +22,7 @@
 #                                             source_cohort_start_year: 2021,
 #                                             schedule:).save
 #
-#  - For cohort changes on participants whose current cohort has been payments_frozen and are moved to
+#  - For cohort changes on participants whose current cohort has been payments_frozen and are transferred to
 #    the active registration cohort, it will automatically flag the participant_profile as
 #    cohort_changed_after_payments_frozen: true
 #
@@ -63,23 +63,22 @@ class AmendParticipantCohort
               },
               on: :start
 
-    validate :target_cohort_payments_active
-
     validates :participant_profile,
               presence: true,
               on: :start
 
     validate :target_cohort_start_year_matches_schedule
 
     validates :participant_profile,
-              active_participant_profile: true,
-              unfinished_training_participant_profile: true
+              active_participant_profile: true
 
-    validate :eligible_to_be_moved_after_payments_frozen, if: :cohort_changed_after_payments_frozen
+    validate :target_cohort_payments_active, unless: :back_to_payments_frozen_cohort?
+    validate :transfer_from_payments_frozen_cohort, if: :transfer_from_payments_frozen_cohort?
+    validate :transfer_to_payments_frozen_cohort, if: :back_to_payments_frozen_cohort?
 
     validates :participant_declarations,
               absence: { message: :billable_or_submitted },
-              unless: :cohort_changed_after_payments_frozen
+              unless: :payments_frozen_transfer?
 
     validates :induction_record,
               presence: {
@@ -98,10 +97,6 @@ class AmendParticipantCohort
 
     delegate :school, to: :induction_record, allow_nil: true
 
-    def cohort_changed_after_payments_frozen
-      source_cohort&.payments_frozen? && target_cohort == Cohort.active_registration_cohort
-    end
-
     def save
       return false unless valid?(:start)
       return true if in_target?(induction_record)
@@ -116,6 +111,14 @@ def initialize(*)
       @target_cohort_start_year = (@target_cohort_start_year || @schedule&.cohort_start_year).to_i
     end
 
+    def back_to_payments_frozen_cohort?
+      participant_profile&.cohort_changed_after_payments_frozen? && target_cohort&.payments_frozen?
+    end
+
+    def billable_declarations_in_cohort?(cohort)
+      participant_profile.participant_declarations.where(cohort:).billable.exists?
+    end
+
     def current_induction_record_updated?
       ActiveRecord::Base.transaction do
         Induction::ChangeInductionRecord.call(induction_record:,
@@ -166,14 +169,7 @@ def participant_declarations
       return false unless participant_profile
       return @participant_declarations if instance_variable_defined?(:@participant_declarations)
 
-      @participant_declarations = if cohort_changed_after_payments_frozen
-
-                                  else
-                                    participant_profile
-                                      .participant_declarations
-                                      .billable_or_changeable
-                                      .exists?
-                                  end
+      @participant_declarations = participant_profile.participant_declarations.billable_or_changeable.exists?
     end
 
     def schedule
@@ -198,15 +194,31 @@ def target_school_cohort
       @target_school_cohort ||= SchoolCohort.find_by(school:, cohort: target_cohort)
     end
 
+    def payments_frozen_transfer?
+      transfer_from_payments_frozen_cohort? || back_to_payments_frozen_cohort?
+    end
+
+    def transfer_from_payments_frozen_cohort?
+      source_cohort&.payments_frozen? && target_cohort == Cohort.active_registration_cohort
+    end
+
+    alias_method :cohort_changed_after_payments_frozen, :transfer_from_payments_frozen_cohort?
+
     # Validations
-    def eligible_to_be_moved_after_payments_frozen
+
+    def target_cohort_payments_active
+      errors.add(:target_cohort_start_year, :payments_frozen) if target_cohort&.payments_frozen?
+    end
+
+    def transfer_from_payments_frozen_cohort
       unless participant_profile.eligible_to_change_cohort_and_continue_training?
-        errors.add(:participant_profile, :participant_not_eligible_to_be_moved)
+        errors.add(:participant_profile, :not_eligible_to_be_transferred_from_current_cohort)
       end
     end
 
-    def target_cohort_payments_active
-      errors.add(:target_cohort_start_year, :payments_frozen) if target_cohort&.payments_frozen?
+    def transfer_to_payments_frozen_cohort
+      errors.add(:participant_profile, :billable_declarations_in_cohort) if billable_declarations_in_cohort?(source_cohort)
+      errors.add(:participant_profile, :no_billable_declarations_in_cohort) unless billable_declarations_in_cohort?(target_cohort)
     end
 
     def target_cohort_start_year_matches_schedule

config/locales/en.yml

@@ -321,13 +321,15 @@ en:
               no_default_induction_programme: "No default induction programme set for %{start_academic_year} academic year by school %{school_name}"
               school_cohort_not_setup: "%{start_academic_year} academic year not setup by school %{school_name}"
             participant_declarations:
-              exist: "The participant must have no declarations"
               billable_or_submitted: "The participant has billable or submitted declarations"
               completed: "The participant has not had a 'completed' declaration submitted for them. Therefore you cannot update their outcome."
             participant_profile:
+              billable_declarations_in_cohort: "The participant has billable declarations in their current cohort"
+              no_billable_declarations_in_cohort: "The participant has no billable declarations in destination cohort"
               blank: "Not registered"
               not_active: "Not active"
-              not_eligible_to_be_moved: "Not eligible to be moved from their current cohort"
+              not_eligible_to_be_transferred_back: "Not eligible to be transferred back to their original cohort"
+              not_eligible_to_be_transferred_from_current_cohort: "Not eligible to be transferred from their current cohort"
             source_cohort_start_year:
               invalid: "Invalid value. Must be an integer between %{start} and %{end}"
             target_cohort_start_year: