Show outstanding balance on orders page

Prior to this change, there was no way of knowing how much was owed (or
in need of refunding) at a glance for each order on the orders index page,
this information was only available by clicking through to an order
payment page

This change adds the outstanding balance for each order

app/serializers/api/admin/order_serializer.rb

@@ -3,7 +3,7 @@ class Api::Admin::OrderSerializer < ActiveModel::Serializer
              :edit_path, :state, :payment_state, :shipment_state,
              :payments_path, :ready_to_ship, :ready_to_capture, :created_at,
              :distributor_name, :special_instructions,
-             :item_total, :adjustment_total, :payment_total, :total
+             :item_total, :adjustment_total, :payment_total, :total, :display_outstanding_balance
 
   has_one :distributor, serializer: Api::Admin::IdSerializer
   has_one :order_cycle, serializer: Api::Admin::IdSerializer
@@ -16,6 +16,12 @@ class Api::Admin::OrderSerializer < ActiveModel::Serializer
     object.distributor.andand.name
   end
 
+  def display_outstanding_balance
+    return "" unless ["balance_due", "credit_owed"].include?(object.payment_state)
+
+    "(#{object.display_outstanding_balance.to_html})"
+  end
+
   def edit_path
     return '' unless object.id
 

app/views/spree/admin/orders/index.html.haml

@@ -68,6 +68,7 @@
         %span.state{'ng-class' => 'order.payment_state', 'ng-if' => 'order.payment_state'}
           %a{'ng-href' => '{{order.payments_path}}' }
             {{'js.admin.orders.payment_states.' + order.payment_state | t}}
+            {{order.display_outstanding_balance}}
       %td.align-center
         %span.state{'ng-class' => 'order.shipment_state', 'ng-if' => 'order.shipment_state'}
           {{'js.admin.orders.shipment_states.' + order.shipment_state | t}}

spec/factories/order_factory.rb

@@ -46,8 +46,12 @@ FactoryBot.define do
     distributor { create(:distributor_enterprise) }
     order_cycle { create(:simple_order_cycle) }
 
-    after(:create) do |order|
-      create(:payment, amount: order.total + 10_000, order: order, state: "completed")
+    transient do
+      credit_amount { 10_000 }
+    end
+
+    after(:create) do |order, evaluator|
+      create(:payment, amount: order.total + evaluator.credit_amount, order: order, state: "completed")
       order.reload
     end
   end
@@ -56,8 +60,12 @@ FactoryBot.define do
     distributor { create(:distributor_enterprise) }
     order_cycle { create(:simple_order_cycle) }
 
-    after(:create) do |order|
-      create(:payment, amount: order.total - 1, order: order, state: "completed")
+    transient do
+      unpaid_amount { 1 }
+    end
+
+    after(:create) do |order, evaluator|
+      create(:payment, amount: order.total - evaluator.unpaid_amount, order: order, state: "completed")
       order.reload
     end
   end

spec/serializers/api/admin/order_serializer_spec.rb

@@ -0,0 +1,29 @@
+require "spec_helper"
+
+describe Api::Admin::OrderSerializer do
+  let(:serializer) { described_class.new order }
+
+  describe "#display_outstanding_balance" do
+    let(:order) { create(:order) }
+
+    it "returns empty string" do
+      expect(serializer.display_outstanding_balance).to eql("")
+    end
+
+    context "with outstanding payments" do
+      let(:order) { create(:order_without_full_payment, unpaid_amount: 10) }
+
+      it "generates the outstanding balance" do
+        expect(serializer.display_outstanding_balance).to eql("($10.00)")
+      end
+    end
+
+    context "with credit owed" do
+      let(:order) { create(:order_with_credit_payment, credit_amount: 20) }
+
+      it "generates the outstanding balance" do
+        expect(serializer.display_outstanding_balance).to eql("($-20.00)")
+      end
+    end
+  end
+end