Further simplify Order by outsourcing to service class

app/models/spree/order.rb

@@ -707,17 +707,8 @@ module Spree
       persisted? && state != "cart"
     end
 
-    def email_for_customer
-      (user&.email || email)&.downcase
-    end
-
-    def find_customer
-      user&.customers&.of(distributor)&.first ||
-        Customer.of(distributor).find_by(email: email_for_customer)
-    end
-
     def ensure_customer
-      self.customer ||= find_customer
+      self.customer ||= CustomerSyncer.find_customer(self)
       self.customer ||= CustomerSyncer.create_customer(self) if require_customer?
 
       CustomerSyncer.new(self).synchronise_customer_email

app/services/customer_syncer.rb

@@ -4,10 +4,15 @@
 #
 # P.S.: I almost couldn't resist to call this CustomerService.
 class CustomerSyncer
+  def self.find_customer(order)
+    order.user&.customers&.of(order.distributor)&.first ||
+      Customer.of(order.distributor).find_by(email: customer_email(order))
+  end
+
   def self.create_customer(order)
     Customer.create(
       enterprise: order.distributor,
-      email: (order.user&.email || order.email)&.downcase,
+      email: customer_email(order),
       user: order.user,
       first_name: order.bill_address&.first_name.to_s,
       last_name: order.bill_address&.last_name.to_s,
@@ -16,6 +21,10 @@ class CustomerSyncer
     )
   end
 
+  def self.customer_email(order)
+    (order.user&.email || order.email)&.downcase
+  end
+
   attr_reader :customer, :distributor, :user
 
   def initialize(order)