Infer LA fields from postcode

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

@@ -9,6 +9,16 @@ class Form::Sales::Questions::PostcodeKnown < ::Form::Question
     @conditional_for = {
       "postcode_full" => [0],
     }
+    @hidden_in_check_answers = {
+      "depends_on" => [
+        {
+          "pcodenk" => 0,
+        },
+        {
+          "pcodenk" => 1,
+        },
+      ],
+    }
   end
 
   ANSWER_OPTIONS = {

app/models/lettings_log.rb

@@ -607,10 +607,6 @@ private
     self[la_key] = inferred_la if inferred_la.present?
   end
 
-  def reset_location_fields!
-    reset_location(is_la_inferred, "la", "is_la_inferred", "postcode_full", 1)
-  end
-
   def get_has_benefits
     HAS_BENEFITS_OPTIONS.include?(hb) ? 1 : 0
   end

app/models/log.rb

@@ -105,6 +105,10 @@ private
     string.present? ? string.upcase.gsub(/\s+/, "") : string
   end
 
+  def reset_location_fields!
+    reset_location(is_la_inferred, "la", "is_la_inferred", "postcode_full", 1)
+  end
+
   def reset_previous_location_fields!
     reset_location(is_previous_la_inferred, "prevloc", "is_previous_la_inferred", "ppostcode_full", previous_la_known)
   end

app/models/sales_log.rb

@@ -21,7 +21,9 @@ class SalesLog < Log
   validates_with SalesLogValidator
   before_validation :set_derived_fields!
   before_validation :reset_invalidated_dependent_fields!
+  before_validation :process_postcode_changes!, if: :postcode_full_changed?
   before_validation :process_previous_postcode_changes!, if: :ppostcode_full_changed?
+  before_validation :reset_location_fields!, unless: :postcode_known?
   before_validation :reset_previous_location_fields!, unless: :previous_postcode_known?
 
   scope :filter_by_year, ->(year) { where(saledate: Time.zone.local(year.to_i, 4, 1)...Time.zone.local(year.to_i + 1, 4, 1)) }
@@ -135,6 +137,18 @@ class SalesLog < Log
     ppcodenk&.zero?
   end
 
+  def postcode_known?
+    pcodenk&.zero?
+  end
+
+  def postcode_full=(postcode)
+    if postcode
+      super UKPostcode.parse(postcode).to_s
+    else
+      super nil
+    end
+  end
+
   def process_postcode(postcode, postcode_known_key, la_inferred_key, la_key)
     return if postcode.blank?
 
@@ -151,4 +165,9 @@ class SalesLog < Log
   def mortgage_not_used?
     mortgageused == 2
   end
+
+  def process_postcode_changes!
+    self.postcode_full = upcase_and_remove_whitespace(postcode_full)
+    process_postcode(postcode_full, "pcodenk", "is_la_inferred", "la")
+  end
 end

spec/factories/sales_log.rb

@@ -57,7 +57,7 @@ FactoryBot.define do
       income2nk { 0 }
       income2 { 10_000 }
       inc2mort { 1 }
-      la_known { "1" }
+      la_known { 1 }
       la { "E09000003" }
       savingsnk { 1 }
       prevown { 1 }
@@ -96,6 +96,8 @@ FactoryBot.define do
       mscharge_known { 1 }
       mscharge { 100 }
       mortlen { 10 }
+      pcodenk { 1 }
+      is_la_inferred { false }
     end
   end
 end

spec/models/form/sales/questions/postcode_known_spec.rb

@@ -47,4 +47,13 @@ RSpec.describe Form::Sales::Questions::PostcodeKnown, type: :model do
   it "has the correct hint" do
     expect(question.hint_text).to be_nil
   end
+
+  it "has the correct hidden_in_check_answers" do
+    expect(question.hidden_in_check_answers).to eq({
+      "depends_on" => [
+        { "pcodenk" => 0 },
+        { "pcodenk" => 1 },
+      ],
+    })
+  end
 end

spec/models/form_handler_spec.rb

@@ -52,14 +52,14 @@ RSpec.describe FormHandler do
     it "is able to load a current sales form" do
       form = form_handler.get_form("current_sales")
       expect(form).to be_a(Form)
-      expect(form.pages.count).to eq(137)
+      expect(form.pages.count).to eq(138)
       expect(form.name).to eq("2022_2023_sales")
     end
 
     it "is able to load a previous sales form" do
       form = form_handler.get_form("previous_sales")
       expect(form).to be_a(Form)
-      expect(form.pages.count).to eq(137)
+      expect(form.pages.count).to eq(138)
       expect(form.name).to eq("2021_2022_sales")
     end
   end

spec/models/sales_log_spec.rb

@@ -129,6 +129,102 @@ RSpec.describe SalesLog, type: :model do
     end
   end
 
+  context "when saving addresses" do
+    before do
+      stub_request(:get, /api.postcodes.io/)
+        .to_return(status: 200, body: "{\"status\":200,\"result\":{\"admin_district\":\"Manchester\",\"codes\":{\"admin_district\": \"E08000003\"}}}", headers: {})
+    end
+
+    def check_postcode_fields(postcode_field)
+      record_from_db = ActiveRecord::Base.connection.execute("select #{postcode_field} from sales_logs where id=#{address_sales_log.id}").to_a[0]
+      expect(address_sales_log[postcode_field]).to eq("M1 1AE")
+      expect(record_from_db[postcode_field]).to eq("M1 1AE")
+    end
+
+    let!(:address_sales_log) do
+      FactoryBot.create(
+        :sales_log,
+        :completed,
+        managing_organisation: owning_organisation,
+        owning_organisation:,
+        created_by: created_by_user,
+        pcodenk: 0,
+        postcode_full: "M1 1AE",
+      )
+    end
+
+    def check_property_postcode_fields
+      check_postcode_fields("postcode_full")
+    end
+
+    it "correctly formats previous postcode" do
+      address_sales_log.update!(postcode_full: "M1 1AE")
+      check_property_postcode_fields
+
+      address_sales_log.update!(postcode_full: "m1 1ae")
+      check_property_postcode_fields
+
+      address_sales_log.update!(postcode_full: "m11Ae")
+      check_property_postcode_fields
+
+      address_sales_log.update!(postcode_full: "m11ae")
+      check_property_postcode_fields
+    end
+
+    it "correctly infers la" do
+      record_from_db = ActiveRecord::Base.connection.execute("select la from sales_logs where id=#{address_sales_log.id}").to_a[0]
+      expect(address_sales_log.la).to eq("E08000003")
+      expect(record_from_db["la"]).to eq("E08000003")
+    end
+
+    it "errors if the property postcode is emptied" do
+      expect { address_sales_log.update!({ postcode_full: "" }) }
+        .to raise_error(ActiveRecord::RecordInvalid, /#{I18n.t("validations.postcode")}/)
+    end
+
+    it "errors if the property postcode is not valid" do
+      expect { address_sales_log.update!({ postcode_full: "invalid_postcode" }) }
+        .to raise_error(ActiveRecord::RecordInvalid, /#{I18n.t("validations.postcode")}/)
+    end
+
+    context "when the local authority lookup times out" do
+      before do
+        allow(Timeout).to receive(:timeout).and_raise(Timeout::Error)
+      end
+
+      it "logs a warning" do
+        expect(Rails.logger).to receive(:warn).with("Postcodes.io lookup timed out")
+        address_sales_log.update!({ pcodenk: 1, postcode_full: "M1 1AD" })
+      end
+    end
+
+    it "correctly resets all fields if property postcode not known" do
+      address_sales_log.update!({ pcodenk: 1 })
+
+      record_from_db = ActiveRecord::Base.connection.execute("select la, postcode_full from sales_logs where id=#{address_sales_log.id}").to_a[0]
+      expect(record_from_db["postcode_full"]).to eq(nil)
+      expect(address_sales_log.la).to eq(nil)
+      expect(record_from_db["la"]).to eq(nil)
+    end
+
+    it "changes the LA if property postcode changes from not known to known and provided" do
+      address_sales_log.update!({ pcodenk: 1 })
+      address_sales_log.update!({ la: "E09000033" })
+
+      record_from_db = ActiveRecord::Base.connection.execute("select la, postcode_full from sales_logs where id=#{address_sales_log.id}").to_a[0]
+      expect(record_from_db["postcode_full"]).to eq(nil)
+      expect(address_sales_log.la).to eq("E09000033")
+      expect(record_from_db["la"]).to eq("E09000033")
+
+      address_sales_log.update!({ pcodenk: 0, postcode_full: "M1 1AD" })
+
+      record_from_db = ActiveRecord::Base.connection.execute("select la, postcode_full from sales_logs where id=#{address_sales_log.id}").to_a[0]
+      expect(record_from_db["postcode_full"]).to eq("M1 1AD")
+      expect(address_sales_log.la).to eq("E08000003")
+      expect(record_from_db["la"]).to eq("E08000003")
+    end
+  end
+
   context "when saving previous address" do
     def check_previous_postcode_fields(postcode_field)
       record_from_db = ActiveRecord::Base.connection.execute("select #{postcode_field} from sales_logs where id=#{address_sales_log.id}").to_a[0]