Merge pull request #6391 from Matt-Yorkley/paypal-stock-clashes

Paypal stock clashes

app/controllers/checkout_controller.rb

@@ -5,6 +5,7 @@ require 'open_food_network/address_finder'
 class CheckoutController < Spree::StoreController
   layout 'darkswarm'
 
+  include OrderStockCheck
   include CheckoutHelper
   include OrderCyclesHelper
   include EnterprisesHelper
@@ -24,7 +25,7 @@ class CheckoutController < Spree::StoreController
 
   before_action :ensure_order_not_completed
   before_action :ensure_checkout_allowed
-  before_action :ensure_sufficient_stock_lines
+  before_action :handle_insufficient_stock
 
   before_action :associate_user
   before_action :check_authorization
@@ -77,13 +78,6 @@ class CheckoutController < Spree::StoreController
     redirect_to main_app.cart_path if @order.completed?
   end
 
-  def ensure_sufficient_stock_lines
-    if @order.insufficient_stock_lines.present?
-      flash[:error] = Spree.t(:inventory_error_flash_for_insufficient_quantity)
-      redirect_to main_app.cart_path
-    end
-  end
-
   def load_order
     @order = current_order
 

app/controllers/concerns/order_stock_check.rb

@@ -0,0 +1,18 @@
+# frozen_string_literal: true
+
+module OrderStockCheck
+  extend ActiveSupport::Concern
+
+  def handle_insufficient_stock
+    return if sufficient_stock?
+
+    flash[:error] = Spree.t(:inventory_error_flash_for_insufficient_quantity)
+    redirect_to main_app.cart_path
+  end
+
+  private
+
+  def sufficient_stock?
+    @sufficient_stock ||= @order.insufficient_stock_lines.blank?
+  end
+end

app/controllers/spree/paypal_controller_decorator.rb

@@ -1,6 +1,8 @@
 # frozen_string_literal: true
 
 Spree::PaypalController.class_eval do
+  include OrderStockCheck
+
   before_action :enable_embedded_shopfront
   before_action :destroy_orphaned_paypal_payments, only: :confirm
   after_action :reset_order_when_complete, only: :confirm
@@ -40,6 +42,9 @@ Spree::PaypalController.class_eval do
     begin
       pp_response = provider.set_express_checkout(pp_request)
       if pp_response.success?
+        # At this point Paypal has *provisionally* accepted that the payment can now be placed,
+        # and the user will be redirected to a Paypal payment page. On completion, the user is
+        # sent back and the response is handled in the #confirm action in this controller.
         redirect_to provider.express_checkout_url(pp_response, useraction: 'commit')
       else
         flash[:error] = Spree.t('flash.generic_error', scope: 'paypal', reasons: pp_response.errors.map(&:long_message).join(" "))
@@ -51,6 +56,32 @@ Spree::PaypalController.class_eval do
     end
   end
 
+  def confirm
+    @order = current_order || raise(ActiveRecord::RecordNotFound)
+
+    # At this point the user has come back from the Paypal form, and we get one
+    # last chance to interact with the payment process before the money moves...
+    return reset_to_cart unless sufficient_stock?
+
+    @order.payments.create!({
+      source: Spree::PaypalExpressCheckout.create({
+        token: params[:token],
+        payer_id: params[:PayerID]
+      }),
+      amount: @order.total,
+      payment_method: payment_method
+    })
+    @order.next
+    if @order.complete?
+      flash.notice = Spree.t(:order_processed_successfully)
+      flash[:commerce_tracking] = "nothing special"
+      session[:order_id] = nil
+      redirect_to completion_route(@order)
+    else
+      redirect_to checkout_state_path(@order.state)
+    end
+  end
+
   def cancel
     flash[:notice] = Spree.t('flash.cancel', scope: 'paypal')
     redirect_to main_app.checkout_path
@@ -66,6 +97,10 @@ Spree::PaypalController.class_eval do
 
   private
 
+  def payment_method
+    @payment_method ||= Spree::PaymentMethod.find(params[:payment_method_id])
+  end
+
   def permit_parameters!
     params.permit(:token, :payment_method_id, :PayerID)
   end
@@ -79,6 +114,11 @@ Spree::PaypalController.class_eval do
     end
   end
 
+  def reset_to_cart
+    OrderCheckoutRestart.new(@order).call
+    handle_insufficient_stock
+  end
+
   # See #1074 and #1837 for more detail on why we need this
   # An 'orphaned' Spree::Payment is created for every call to CheckoutController#update
   # for orders that are processed using a Spree::Gateway::PayPalExpress payment method