Add ability to set a default brand for organisation

app/controllers/organisation_brands_controller.rb

@@ -23,11 +23,31 @@ def destroy
     authorize organisation, :can_manage_organisation_brands?
 
     organisation_brand = organisation.organisation_brands.find_by!(brand_id: params[:id])
+
+    if organisation.default_brand_id == organisation_brand.brand_id
+      return redirect_to organisation_path(organisation), status: :see_other
+    end
+
     organisation_brand.destroy!
 
     redirect_to organisation_path(organisation), success: t(".success", brand_name: organisation_brand.brand.name)
   end
 
+  def update_default
+    authorize organisation, :can_manage_organisation_brands?
+
+    if params[:brand_id].present?
+      brand = organisation.brands.find(params[:brand_id])
+      organisation.update!(default_brand: brand)
+
+      redirect_to organisation_path(organisation), success: t(".success", brand_name: brand.name)
+    else
+      organisation.update!(default_brand: nil)
+
+      redirect_to organisation_path(organisation), success: t(".success_govuk")
+    end
+  end
+
 private
 
   def organisation

app/models/organisation.rb

@@ -11,6 +11,10 @@ class Organisation < ApplicationRecord
   has_many :organisation_brands, dependent: :destroy
   has_many :brands, -> { order(:name) }, through: :organisation_brands
 
+  belongs_to :default_brand, class_name: "Brand", optional: true
+
+  validate :default_brand_is_available, if: :default_brand_id_changed?
+
   scope :not_closed, -> { where(closed: false) }
   scope :with_users, -> { joins(:users).distinct.order(:name) }
 
@@ -73,4 +77,13 @@ def as_json(options = {})
     options[:methods] ||= %i[organisation_admin_users]
     super(options)
   end
+
+private
+
+  def default_brand_is_available
+    return if default_brand_id.nil?
+    return if organisation_brands.exists?(brand_id: default_brand_id)
+
+    errors.add(:default_brand, :not_available)
+  end
 end

app/services/create_form_service.rb

@@ -34,11 +34,19 @@ def create!(creator:, group:, name:)
     if event.form_id.present?
       form = Form.find(event.form_id)
     else
-      form = Form.create!(creator_id: creator.id, name:)
+      form = Form.create!(creator_id: creator.id, name:, brand_id: default_brand_id(group))
       GroupForm.create!(group:, form_id: form.id)
       event.update!(form_id: form.id)
     end
 
     form
   end
+
+private
+
+  def default_brand_id(group)
+    return nil unless FeatureService.new(group:).enabled?(:custom_branding)
+
+    group.organisation.default_brand&.slug
+  end
 end

app/views/organisations/show.html.erb

@@ -113,30 +113,51 @@
 
     <h2 class="govuk-heading-m"><%= t("organisations.show.brands.heading") %></h2>
     <p class="govuk-body"><%= t("organisations.show.brands.guidance") %></p>
-    <% if @organisation.brands.any? %>
-      <%= render ScrollingWrapperComponent::View.new(aria_label: t("organisations.show.brands.heading")) do %>
-        <%= govuk_table do |table| %>
-          <%= table.with_head do |head|
-            head.with_row do |row|
-              row.with_cell(header: true, text: t("organisations.show.brands.table_headings.name"))
-              row.with_cell(header: true, text: t("organisations.show.brands.table_headings.actions"))
-            end
-          end %>
-
-          <%= table.with_body do |body| %>
-            <% @organisation.brands.each do |brand| %>
-              <%= body.with_row do |row| %>
-                <%= row.with_cell { govuk_link_to(brand.name, brand_path(brand)) } %>
-                <%= row.with_cell do %>
-                  <%= govuk_button_to(t("organisations.show.brands.remove"), organisation_brand_path(@organisation, brand), method: :delete, secondary: true) %>
+    <%= render ScrollingWrapperComponent::View.new(aria_label: t("organisations.show.brands.heading")) do %>
+      <%= govuk_table do |table| %>
+        <%= table.with_head do |head|
+          head.with_row do |row|
+            row.with_cell(header: true, text: t("organisations.show.brands.table_headings.name"))
+            row.with_cell(header: true, text: t("organisations.show.brands.table_headings.actions"))
+          end
+        end %>
+
+        <%= table.with_body do |body| %>
+          <%= body.with_row do |row| %>
+            <%= row.with_cell do %>
+              <%= t("organisations.show.brands.govuk_brand_name") %>
+              <% if @organisation.default_brand_id.nil? %>
+                <%= govuk_tag(text: t("organisations.show.brands.default_tag"), colour: "green") %>
+              <% end %>
+            <% end %>
+            <%= row.with_cell do %>
+              <% if @organisation.default_brand_id.present? %>
+                <%= govuk_button_to(t("organisations.show.brands.make_default"), organisation_default_brand_path(@organisation), method: :patch, secondary: true, visually_hidden_suffix: t("organisations.show.brands.govuk_brand_name"), class: "govuk-!-margin-bottom-0") %>
+              <% end %>
+            <% end %>
+          <% end %>
+          <% @organisation.brands.each do |brand| %>
+            <%= body.with_row do |row| %>
+              <%= row.with_cell do %>
+                <%= govuk_link_to(brand.name, brand_path(brand)) %>
+                <% if brand.id == @organisation.default_brand_id %>
+                  <%= govuk_tag(text: t("organisations.show.brands.default_tag"), colour: "green") %>
+                <% end %>
+              <% end %>
+              <%= row.with_cell do %>
+                <% if brand.id == @organisation.default_brand_id %>
+                  <%= govuk_button_to(t("organisations.show.brands.remove"), organisation_brand_path(@organisation, brand), method: :delete, secondary: true, disabled: true, visually_hidden_suffix: brand.name, class: "govuk-!-margin-bottom-0") %>
+                <% else %>
+                  <div class="govuk-button-group govuk-!-margin-bottom-0">
+                    <%= govuk_button_to(t("organisations.show.brands.make_default"), organisation_default_brand_path(@organisation), method: :patch, params: { brand_id: brand.id }, secondary: true, visually_hidden_suffix: brand.name, class: "govuk-!-margin-bottom-0") %>
+                    <%= govuk_button_to(t("organisations.show.brands.remove"), organisation_brand_path(@organisation, brand), method: :delete, secondary: true, visually_hidden_suffix: brand.name, class: "govuk-!-margin-bottom-0") %>
+                  </div>
                 <% end %>
               <% end %>
             <% end %>
           <% end %>
         <% end %>
       <% end %>
-    <% else %>
-      <p class="govuk-body"><%= t("organisations.show.brands.none") %></p>
     <% end %>
 
     <%= govuk_button_link_to t("organisations.show.brands.add"), new_organisation_brand_path(@organisation), secondary: true %>

config/locales/en.yml

@@ -176,6 +176,10 @@ en:
             agreed:
               crown: You must agree to the memorandum of understanding
               non_crown: You must agree to the agreement to continue
+        organisation:
+          attributes:
+            default_brand:
+              not_available: The default brand must be one of the organisation’s available brands
         organisation_domain:
           attributes:
             domain:
@@ -1501,6 +1505,9 @@ en:
       prompt: Select a brand
       submit: Add brand
       title: Add a brand
+    update_default:
+      success: "%{brand_name} is now the default brand for new forms in this organisation"
+      success_govuk: New forms in this organisation will use GOV.UK branding
   organisations:
     boolean:
       'false': 'No'
@@ -1545,9 +1552,11 @@ en:
         none: This organisation does not have any organisation admins.
       brands:
         add: Add a brand
-        guidance: Add brands to make them available for forms in this organisation to use. Forms that already use a brand will continue to use it, even if you remove the brand from this organisation.
+        default_tag: Default
+        govuk_brand_name: GOV.UK
+        guidance: Add brands to make them available for forms in this organisation to use. New forms will use the default brand, and people editing a form can change its brand. Forms that already use a brand will continue to use it, even if you remove the brand from this organisation.
         heading: Available brands
-        none: This organisation does not have any available brands. Forms use the default GOV.UK branding.
+        make_default: Make default
         remove: Remove
         table_headings:
           actions: Actions

config/routes.rb

@@ -219,6 +219,7 @@
 
   resources :organisations, only: %i[index show] do
     resources :brands, controller: :organisation_brands, only: %i[new create destroy]
+    patch "default-brand", to: "organisation_brands#update_default", as: :default_brand
   end
 
   resources :brands, only: %i[index show new create edit update]

db/migrate/20260715122206_add_default_brand_to_organisations.rb

@@ -0,0 +1,5 @@
+class AddDefaultBrandToOrganisations < ActiveRecord::Migration[8.1]
+  def change
+    add_reference :organisations, :default_brand, null: true, foreign_key: { to_table: :brands }
+  end
+end

spec/models/organisation_spec.rb

@@ -15,6 +15,43 @@
     end
   end
 
+  describe "default brand" do
+    let(:organisation) { create :organisation }
+    let(:brand) { create :brand }
+
+    it "is valid when the default brand is one of the organisation's brands" do
+      create(:organisation_brand, organisation:, brand:)
+
+      organisation.default_brand = brand
+
+      expect(organisation).to be_valid
+    end
+
+    it "is invalid when the default brand is not one of the organisation's brands" do
+      organisation.default_brand = brand
+
+      expect(organisation).to be_invalid
+      expect(organisation.errors.of_kind?(:default_brand, :not_available)).to be true
+    end
+
+    it "is valid to clear the default brand" do
+      create(:organisation_brand, organisation:, brand:)
+      organisation.update!(default_brand: brand)
+
+      organisation.default_brand = nil
+
+      expect(organisation).to be_valid
+    end
+
+    it "does not validate the default brand unless it is changing" do
+      create(:organisation_brand, organisation:, brand:)
+      organisation.update!(default_brand: brand)
+      organisation.organisation_brands.delete_all
+
+      expect { organisation.update!(name: "Renamed Organisation") }.not_to raise_error
+    end
+  end
+
   describe "scopes" do
     describe ".with_users" do
       it "returns organisations with distinct users" do

spec/requests/organisation_brands_controller_spec.rb

@@ -192,6 +192,103 @@
           expect(response).to have_http_status(:not_found)
         end
       end
+
+      context "when the brand is the organisation's default brand" do
+        before do
+          organisation.update!(default_brand: brand)
+        end
+
+        it "does not remove the brand from the organisation" do
+          expect {
+            delete path
+          }.not_to(change { organisation.brands.count })
+        end
+
+        it "redirects to the organisation page without a success message" do
+          delete path
+
+          expect(response).to redirect_to(organisation_path(organisation))
+          expect(flash[:success]).to be_nil
+        end
+      end
+    end
+  end
+
+  describe "#update_default" do
+    let(:path) { organisation_default_brand_path(organisation) }
+    let(:params) { { brand_id: brand.id } }
+
+    before do
+      create :organisation_brand, organisation:, brand:
+    end
+
+    context "when the user is not a super admin" do
+      before do
+        login_as_standard_user
+
+        patch(path, params:)
+      end
+
+      it "returns http code 403 and renders forbidden" do
+        expect(response).to have_http_status(:forbidden)
+        expect(response).to render_template("errors/forbidden")
+      end
+
+      it "does not change the organisation's default brand" do
+        expect(organisation.reload.default_brand).to be_nil
+      end
+    end
+
+    context "when the user is a super admin" do
+      before do
+        login_as_super_admin_user
+      end
+
+      it "sets the organisation's default brand" do
+        patch(path, params:)
+
+        expect(organisation.reload.default_brand).to eq(brand)
+      end
+
+      it "redirects to the organisation page with a success message" do
+        patch(path, params:)
+
+        expect(response).to redirect_to(organisation_path(organisation))
+        expect(flash[:success]).to eq(I18n.t("organisation_brands.update_default.success", brand_name: brand.name))
+      end
+
+      context "when no brand is given" do
+        let(:params) { {} }
+
+        before do
+          organisation.update!(default_brand: brand)
+        end
+
+        it "clears the organisation's default brand" do
+          patch(path, params:)
+
+          expect(organisation.reload.default_brand).to be_nil
+        end
+
+        it "redirects to the organisation page with a success message" do
+          patch(path, params:)
+
+          expect(response).to redirect_to(organisation_path(organisation))
+          expect(flash[:success]).to eq(I18n.t("organisation_brands.update_default.success_govuk"))
+        end
+      end
+
+      context "when the brand is not one of the organisation's brands" do
+        let(:other_brand) { create :brand }
+        let(:params) { { brand_id: other_brand.id } }
+
+        it "returns http code 404 and does not change the default brand" do
+          patch(path, params:)
+
+          expect(response).to have_http_status(:not_found)
+          expect(organisation.reload.default_brand).to be_nil
+        end
+      end
     end
   end
 end