user upgrades: add ability to refund upgrades.

app/controllers/user_upgrades_controller.rb

@@ -27,6 +27,14 @@ class UserUpgradesController < ApplicationController
     respond_with(@user_upgrade)
   end
 
+  def refund
+    @user_upgrade = authorize UserUpgrade.find(params[:id])
+    @user_upgrade.refund!
+    flash[:notice] = "Upgrade refunded"
+
+    respond_with(@user_upgrade)
+  end
+
   def receipt
     @user_upgrade = authorize UserUpgrade.find(params[:id])
     redirect_to @user_upgrade.receipt_url

app/models/user_upgrade.rb

@@ -11,7 +11,8 @@ class UserUpgrade < ApplicationRecord
   enum status: {
     pending: 0,
     processing: 10,
-    complete: 20
+    complete: 20,
+    refunded: 30,
   }
 
   scope :gifted, -> { where("recipient_id != purchaser_id") }
@@ -62,6 +63,19 @@ class UserUpgrade < ApplicationRecord
     end
   end
 
+  def previous_level
+    case upgrade_type
+    when "gold"
+      User::Levels::MEMBER
+    when "platinum"
+      User::Levels::MEMBER
+    when "gold_to_platinum"
+      User::Levels::GOLD
+    else
+      raise NotImplementedError
+    end
+  end
+
   def upgrade_price
     case upgrade_type
     when "gold"
@@ -120,7 +134,7 @@ class UserUpgrade < ApplicationRecord
   concerning :UpgradeMethods do
     def process_upgrade!(payment_status)
       recipient.with_lock do
-        return if status == "complete"
+        return unless pending? || processing?
 
         if payment_status == "paid"
           upgrade_recipient!
@@ -198,24 +212,38 @@ class UserUpgrade < ApplicationRecord
       checkout
     end
 
+    def refund!(reason: nil)
+      with_lock do
+        return if refunded?
+
+        Stripe::Refund.create(payment_intent: payment_intent.id, reason: reason)
+        recipient.update!(level: previous_level)
+        update!(status: "refunded")
+      end
+    end
+
     def receipt_url
       return nil if pending? || stripe_id.nil?
-
-      checkout_session = Stripe::Checkout::Session.retrieve(stripe_id)
-      payment_intent = Stripe::PaymentIntent.retrieve(checkout_session.payment_intent)
-      charge = payment_intent.charges.data.first
       charge.receipt_url
     end
 
     def payment_url
       return nil if pending? || stripe_id.nil?
-
-      checkout_session = Stripe::Checkout::Session.retrieve(stripe_id)
-      payment_intent = Stripe::PaymentIntent.retrieve(checkout_session.payment_intent)
-
       "https://dashboard.stripe.com/payments/#{payment_intent.id}"
     end
 
+    def checkout_session
+      @checkout_session ||= Stripe::Checkout::Session.retrieve(stripe_id)
+    end
+
+    def payment_intent
+      @payment_intent ||= Stripe::PaymentIntent.retrieve(checkout_session.payment_intent)
+    end
+
+    def charge
+      payment_intent.charges.data.first
+    end
+
     def has_receipt?
       !pending?
     end

app/policies/user_upgrade_policy.rb

@@ -11,6 +11,10 @@ class UserUpgradePolicy < ApplicationPolicy
     record.recipient == user || record.purchaser == user || user.is_owner?
   end
 
+  def refund?
+    user.is_owner? && record.complete?
+  end
+
   def receipt?
     (record.purchaser == user || user.is_owner?) && record.has_receipt?
   end

app/views/user_upgrades/index.html.erb

@@ -40,6 +40,9 @@
         <% if policy(user_upgrade).payment? %>
           | <%= link_to "Payment", payment_user_upgrade_path(user_upgrade), target: "_blank" %>
         <% end %>
+        <% if policy(user_upgrade).refund? %>
+          | <%= link_to "Refund", refund_user_upgrade_path(user_upgrade), remote: true, method: :put, "data-confirm": "Are you sure you want to refund this payment?" %>
+        <% end %>
       <% end %>
     <% end %>
 

app/views/user_upgrades/refund.js.erb

@@ -0,0 +1 @@
+location.reload();

config/routes.rb

@@ -257,6 +257,7 @@ Rails.application.routes.draw do
   resources :user_upgrades, only: [:new, :create, :show, :index] do
     get :receipt, on: :member
     get :payment, on: :member
+    put :refund, on: :member
   end
   resources :user_feedbacks, except: [:destroy]
   resources :user_name_change_requests, only: [:new, :create, :show, :index]

test/functional/user_upgrades_controller_test.rb

@@ -183,6 +183,51 @@ class UserUpgradesControllerTest < ActionDispatch::IntegrationTest
       end
     end
 
+    context "refund action" do
+      mock_stripe!
+
+      context "for a self upgrade" do
+        context "to Gold" do
+          should_eventually "refund the upgrade" do
+            @user_upgrade = create(:self_gold_upgrade, recipient: create(:gold_user), status: "complete")
+            @user_upgrade.create_checkout!
+
+            put_auth refund_user_upgrade_path(@user_upgrade), create(:owner_user), xhr: true
+
+            assert_response :success
+            assert_equal("refunded", @user_upgrade.reload.status)
+            assert_equal(User::Levels::MEMBER, @user_upgrade.recipient.level)
+          end
+        end
+      end
+
+      context "for a gifted upgrade" do
+        context "to Platinum" do
+          should_eventually "refund the upgrade" do
+            @user_upgrade = create(:gift_platinum_upgrade, recipient: create(:platinum_user), status: "complete")
+            @user_upgrade.create_checkout!
+
+            put_auth refund_user_upgrade_path(@user_upgrade), create(:owner_user), xhr: true
+
+            assert_response :success
+            assert_equal("refunded", @user_upgrade.reload.status)
+            assert_equal(User::Levels::MEMBER, @user_upgrade.recipient.level)
+          end
+        end
+      end
+
+      should "not allow unauthorized users to create a refund" do
+        @user_upgrade = create(:self_gold_upgrade, recipient: create(:gold_user), status: "complete")
+        @user_upgrade.create_checkout!
+
+        put_auth refund_user_upgrade_path(@user_upgrade), @user_upgrade.purchaser, xhr: true
+
+        assert_response 403
+        assert_equal("complete", @user_upgrade.reload.status)
+        assert_equal(User::Levels::GOLD, @user_upgrade.recipient.level)
+      end
+    end
+
     context "create action" do
       mock_stripe!
 

test/unit/user_upgrade_test.rb

@@ -82,5 +82,16 @@ class UserUpgradeTest < ActiveSupport::TestCase
         end
       end
     end
+
+    context "the #refund! method" do
+      should_eventually "refund a Gold upgrade" do
+        @user_upgrade = create(:self_gold_upgrade, recipient: create(:gold_user), status: "complete")
+        @user_upgrade.create_checkout!
+        @user_upgrade.refund!
+
+        assert_equal("refunded", @user_upgrade.reload.status)
+        assert_equal(User::Levels::MEMBER, @user_upgrade.recipient.level)
+      end
+    end
   end
 end