Correctly derive variables from new rent type option

app/models/derived_variables/lettings_log_variables.rb

@@ -8,6 +8,7 @@ module DerivedVariables::LettingsLogVariables
     3 => 3, # "Rent to Buy"  => "Intermediate Rent"
     4 => 3, # "London Living Rent"  => "Intermediate Rent"
     5 => 3, # "Other intermediate rent product"  => "Intermediate Rent"
+    6 => 4, # "Specified accommodation - exempt accommodation, managed properties, refuges and local authority hostels"  => "Specified accommodation"
   }.freeze
 
   UNITLETAS_MAPPING = {
@@ -17,6 +18,7 @@ module DerivedVariables::LettingsLogVariables
     3 => 6, # "Rent to Buy"  => "Rent to Buy basis"
     4 => 7, # "London Living Rent"  => "London Living Rent basis"
     5 => 8, # "Other intermediate rent product"  => "Another Intermediate Rent basis"
+    6 => 9, # "Specified accommodation - exempt accommodation, managed properties, refuges and local authority hostels"  => "Specified accommodation - exempt accommodation, manged properties, refuges and local authority hostels"
   }.freeze
 
   RENTTYPE_DETAIL_MAPPING = {
@@ -26,6 +28,7 @@ module DerivedVariables::LettingsLogVariables
     3 => 4,
     4 => 5,
     5 => 6,
+    6 => 7,
   }.freeze
 
   def set_derived_fields!

app/models/lettings_log.rb

@@ -146,7 +146,7 @@ class LettingsLog < Log
 
   AUTOGENERATED_FIELDS = %w[id status created_at updated_at discarded_at].freeze
   OPTIONAL_FIELDS = %w[tenancycode propcode chcharge].freeze
-  RENT_TYPE_MAPPING_LABELS = { 1 => "Social Rent", 2 => "Affordable Rent", 3 => "Intermediate Rent" }.freeze
+  RENT_TYPE_MAPPING_LABELS = { 1 => "Social Rent", 2 => "Affordable Rent", 3 => "Intermediate Rent", 4 => "Specified accommodation" }.freeze
   HAS_BENEFITS_OPTIONS = [1, 6, 8, 7].freeze
   NUM_OF_WEEKS_FROM_PERIOD = { 2 => 26, 3 => 13, 4 => 12, 5 => 50, 6 => 49, 7 => 48, 8 => 47, 9 => 46, 1 => 52, 10 => 53 }.freeze
   SUFFIX_FROM_PERIOD = { 2 => "every 2 weeks", 3 => "every 4 weeks", 4 => "every month" }.freeze
@@ -158,6 +158,7 @@ class LettingsLog < Log
     rent_to_buy: 3,
     london_living_rent: 4,
     other_intermediate_rent_product: 5,
+    specified_accommodation: 6,
   }.freeze
 
   def form
@@ -826,6 +827,12 @@ private
       elsif is_general_needs?
         owning_organisation[:provider_type] == "PRP" ? 9 : 11
       end
+    when "Specified accommodation"
+      if is_supported_housing?
+        owning_organisation[:provider_type] == "PRP" ? 14 : 16
+      elsif is_general_needs?
+        owning_organisation[:provider_type] == "PRP" ? 13 : 15
+      end
     end
   end
 

spec/models/lettings_log_derived_fields_spec.rb

@@ -187,6 +187,18 @@ RSpec.describe LettingsLog, type: :model do
           needstype: 1,
           expected_lettype: 1,
         },
+        {
+          context: "when the rent type is Specified accommodation and supported housing",
+          rent_type: 6,
+          needstype: 2,
+          expected_lettype: 14,
+        },
+        {
+          context: "when the rent type is Specified accommodation and general needs housing",
+          rent_type: 6,
+          needstype: 1,
+          expected_lettype: 13,
+        },
       ].each do |test_case|
         context test_case[:context] do
           it "correctly derives lettype" do
@@ -953,6 +965,11 @@ RSpec.describe LettingsLog, type: :model do
       log.rent_type = 5
       expect { log.set_derived_fields! }.to change(log, :renttype).to 3
     end
+
+    it "when rent_type is Specified accommodation derives renttype as Specified accommodation" do
+      log.rent_type = 6
+      expect { log.set_derived_fields! }.to change(log, :renttype).to 4
+    end
   end
 
   describe "variables dependent on whether a letting is a renewal" do
@@ -1168,6 +1185,25 @@ RSpec.describe LettingsLog, type: :model do
           expect { persisted_renewal_lettings_log.update!(renewal: 0) }.to change(persisted_renewal_lettings_log, :unitletas).from(expected_unitletas).to nil
         end
       end
+
+      context "when rent_type is Specified accommodation " do
+        let(:rent_type) { 6 }
+        let(:expected_unitletas) { 9 }
+
+        before do
+          Timecop.freeze(Time.zone.local(2025, 5, 5))
+        end
+
+        it "derives the most recent let type as London Living Rent basis if it is a renewal" do
+          log.assign_attributes(renewal: 1, rent_type:)
+
+          expect { log.set_derived_fields! }.to change(log, :unitletas).to expected_unitletas
+        end
+
+        it "clears the most recent let type if it is not a renewal" do
+          expect { persisted_renewal_lettings_log.update!(renewal: 0) }.to change(persisted_renewal_lettings_log, :unitletas).from(expected_unitletas).to nil
+        end
+      end
     end
   end
 end