Derive single scheme location

Reset location when scheme is changed

app/models/case_log.rb

@@ -24,6 +24,7 @@ class CaseLog < ApplicationRecord
 
   validates_with CaseLogValidator
   before_validation :recalculate_start_year!, if: :startdate_changed?
+  before_validation :reset_scheme_location!, if: :scheme_changed?
   before_validation :process_postcode_changes!, if: :postcode_full_changed?
   before_validation :process_previous_postcode_changes!, if: :ppostcode_full_changed?
   before_validation :reset_invalidated_dependent_fields!
@@ -689,4 +690,8 @@ private
   def upcase_and_remove_whitespace(string)
     string.present? ? string.upcase.gsub(/\s+/, "") : string
   end
+
+  def reset_scheme_location!
+    self.location = nil
+  end
 end

app/models/derived_variables/case_log_variables.rb

@@ -68,6 +68,12 @@ module DerivedVariables::CaseLogVariables
     self.hhtype = household_type
     self.new_old = new_or_existing_tenant
     self.vacdays = property_vacant_days
+
+    if is_supported_housing?
+      if scheme && scheme.locations.size == 1
+        self.location = scheme.locations.first
+      end
+    end
   end
 
 private

spec/models/case_log_spec.rb

@@ -1678,6 +1678,21 @@ RSpec.describe CaseLog do
         expect(case_log["tshortfall_known"]).to eq(0)
       end
     end
+
+    context "when a case log is a supported housing log" do
+      before { case_log.needstype = 2 }
+      context "and a scheme with a single log is selected" do
+        let(:scheme) { FactoryBot.create(:scheme) }
+        let!(:location) { FactoryBot.create(:location, scheme:)}
+        before { case_log.update!(scheme:) }
+
+        it "derives the scheme location" do
+          record_from_db = ActiveRecord::Base.connection.execute("select location_id from case_logs where id=#{case_log.id}").to_a[0]
+          expect(record_from_db["location_id"]).to eq(location.id)
+          expect(case_log["location_id"]).to eq(location.id)
+        end
+      end
+    end
   end
 
   describe "optional fields" do
@@ -2147,4 +2162,6 @@ RSpec.describe CaseLog do
       end
     end
   end
+
+
 end