Add SolidusAdmin::AddressesController

Introduce a new `AddressesController` to handle the creation and updating of
billing and shipping addresses for orders.
Includes new and update actions with strong parameter support and address
type validation.

Author: rainerdema

admin/app/controllers/solidus_admin/addresses_controller.rb

@@ -0,0 +1,66 @@
+# frozen_string_literal: true
+
+module SolidusAdmin
+  class AddressesController < BaseController
+    include Spree::Core::ControllerHelpers::StrongParameters
+
+    before_action :load_order
+    before_action :validate_address_type
+
+    def new
+      address = @order.send("#{address_type}_address")
+      @order.send("build_#{address_type}_address", country_id: default_country_id) if address.nil?
+      address ||= @order.send("#{address_type}_address")
+      address.country_id ||= default_country_id if address.country.nil?
+
+      respond_to do |format|
+      end
+    end
+
+    def update
+      if @order.contents.update_cart(order_params)
+        flash[:notice] = t('.success')
+        redirect_to edit_order_url(@order)
+      else
+        flash.now[:error] = @order.errors.full_messages.join(", ")
+
+        respond_to do |format|
+        end
+      end
+    end
+
+    private
+
+    def address_type
+      params[:type].presence_in(%w[bill ship])
+    end
+
+    def validate_address_type
+      unless address_type
+        flash[:error] = t('.errors.address_type_invalid')
+        redirect_to spree.admin_order_url(@order)
+      end
+    end
+
+    def default_country_id
+      @default_country_id ||= begin
+        country = Spree::Country.default
+        country.id if Spree::Country.available.exists?(id: country.id)
+      end
+    end
+
+    def load_order
+      @order = Spree::Order.find_by!(number: params[:order_id])
+      authorize! action_name, @order
+    end
+
+    def order_params
+      params.require(:order).permit(
+        :use_billing,
+        :use_shipping,
+        bill_address_attributes: permitted_address_attributes,
+        ship_address_attributes: permitted_address_attributes
+      )
+    end
+  end
+end

admin/config/locales/orders.en.yml

@@ -2,3 +2,9 @@ en:
   solidus_admin:
     orders:
       title: "Orders"
+    addresses:
+      title: "Addresses"
+      update:
+        success: "The address has been successfully updated."
+      errors:
+        address_type_invalid: "Invalid address type. Please select either billing or shipping address."