Add organisation validation to sales log

app/models/validations/sales/setup_validations.rb

@@ -41,6 +41,23 @@ module Validations::Sales::SetupValidations
     end
   end
 
+  def validate_organisation(record)
+    return unless record.saledate && record.owning_organisation
+
+    if record.owning_organisation.present?
+      if record.owning_organisation&.merge_date.present? && record.owning_organisation.merge_date < record.saledate
+        record.errors.add :owning_organisation_id, I18n.t("validations.setup.owning_organisation.inactive_merged_organisation",
+                                                          owning_organisation: record.owning_organisation.name,
+                                                          owning_organisation_merge_date: record.owning_organisation.merge_date.to_formatted_s(:govuk_date),
+                                                          owning_absorbing_organisation: record.owning_organisation.absorbing_organisation.name)
+      elsif record.owning_organisation&.absorbed_organisations.present? && record.owning_organisation.created_at > record.saledate
+        record.errors.add :owning_organisation_id, I18n.t("validations.setup.owning_organisation.inactive_absorbing_organisation",
+                                                          owning_organisation: record.owning_organisation.name,
+                                                          owning_organisation_available_from: record.owning_organisation.created_at.to_formatted_s(:govuk_date))
+      end
+    end
+  end
+
 private
 
   def active_collection_start_date

spec/models/validations/sales/setup_validations_spec.rb

@@ -233,4 +233,52 @@ RSpec.describe Validations::Sales::SetupValidations do
       end
     end
   end
+
+  describe "#validate_organisation" do
+    let(:record) { build(:sales_log) }
+
+    context "when organisations are merged" do
+      let(:absorbing_organisation) { create(:organisation, created_at: Time.zone.local(2023, 2, 1), name: "Absorbing org") }
+      let(:merged_organisation) { create(:organisation, name: "Merged org") }
+
+      around do |example|
+        Timecop.freeze(Time.zone.local(2023, 5, 1))
+        merged_organisation.update!(merge_date: Time.zone.local(2023, 2, 2), absorbing_organisation:)
+        example.run
+        Timecop.return
+      end
+
+      context "and owning organisation is no longer active" do
+        it "does not allow organisation that has been merged" do
+          record.saledate = Time.zone.local(2023, 3, 1)
+          record.owning_organisation_id = merged_organisation.id
+          setup_validator.validate_organisation(record)
+          expect(record.errors["owning_organisation_id"]).to include(match "The owning organisation must be active on the tenancy start date. Merged org became inactive on 2 February 2023 and was replaced by Absorbing org.")
+        end
+
+        it "allows organisation before it has been merged" do
+          record.saledate = Time.zone.local(2023, 1, 1)
+          record.owning_organisation_id = merged_organisation.id
+          setup_validator.validate_organisation(record)
+          expect(record.errors["owning_organisation_id"]).to be_empty
+        end
+      end
+
+      context "and owning organisation is not yet active during the saledate" do
+        it "does not allow absorbing organisation before it had been created" do
+          record.saledate = Time.zone.local(2023, 1, 1)
+          record.owning_organisation_id = absorbing_organisation.id
+          setup_validator.validate_organisation(record)
+          expect(record.errors["owning_organisation_id"]).to include(match "The owning organisation must be active on the tenancy start date. Absorbing org became active on 1 February 2023.")
+        end
+
+        it "allows absorbing organisation after it has been created" do
+          record.saledate = Time.zone.local(2023, 2, 2)
+          record.owning_organisation_id = absorbing_organisation.id
+          setup_validator.validate_organisation(record)
+          expect(record.errors["owning_organisation_id"]).to be_empty
+        end
+      end
+    end
+  end
 end