Update insufficient stock logic

We now check for insufficient stock when loading the checkout details
or before updating the order.

app/controllers/checkout_controller.rb

@@ -26,6 +26,7 @@ class CheckoutController < BaseController
     if params[:step].blank?
       redirect_to_step_based_on_order
     else
+      handle_insufficient_stock if details_step?
       update_order_state
       check_step
     end
@@ -36,6 +37,9 @@ class CheckoutController < BaseController
   end
 
   def update
+    return render cable_ready: cable_car.redirect_to(url: checkout_step_path(:details)) \
+      unless sufficient_stock?
+
     if confirm_order || update_order
       return if performed?
 
@@ -152,6 +156,7 @@ class CheckoutController < BaseController
   # state. We need to do this when moving back to a previous checkout step, the update action takes
   # care of moving the order state forward.
   def update_order_state
+    # debugger
     return @order.back_to_payment if @order.confirmation? && payment_step?
 
     return unless @order.after_delivery_state? && details_step?

app/controllers/concerns/checkout_callbacks.rb

@@ -25,7 +25,6 @@ module CheckoutCallbacks
 
     before_action :ensure_order_not_completed
     before_action :ensure_checkout_allowed
-    before_action :handle_insufficient_stock
     before_action :check_authorization
   end
 

app/controllers/concerns/order_stock_check.rb

@@ -5,9 +5,12 @@ module OrderStockCheck
   extend ActiveSupport::Concern
 
   def valid_order_line_items?
-    @order.insufficient_stock_lines.empty? &&
-      OrderCycles::DistributedVariantsService.new(@order.order_cycle, @order.distributor).
-        distributes_order_variants?(@order)
+    OrderCycles::DistributedVariantsService.new(@order.order_cycle, @order.distributor).
+      distributes_order_variants?(@order)
+  end
+
+  def sufficient_stock?
+    Orders::CheckStockService.new(order: @order).sufficient_stock?
   end
 
   def handle_insufficient_stock
@@ -17,6 +20,7 @@ module OrderStockCheck
     return if stock_service.sufficient_stock?
 
     @any_out_of_stock = true
+    @updated_variants = stock_service.update_line_items
   end
 
   def check_order_cycle_expiry

spec/controllers/checkout_controller_spec.rb

@@ -144,6 +144,17 @@ RSpec.describe CheckoutController, type: :controller do
           expect(order.reload.state).to eq "payment"
         end
 
+        context "with insufficient stock" do
+          it "redirects to details page" do
+            allow(order).to receive_message_chain(:insufficient_stock_lines,
+                                                  :empty?).and_return false
+
+            put(:update, params:)
+
+            expect_cable_ready_redirect(response)
+          end
+        end
+
         describe "saving default addresses" do
           it "doesn't update default bill address on user" do
             expect {
@@ -306,6 +317,17 @@ RSpec.describe CheckoutController, type: :controller do
             expect(response).to redirect_to checkout_step_path(:summary)
           end
         end
+
+        context "with insufficient stock" do
+          it "redirects to details page" do
+            allow(order).to receive_message_chain(:insufficient_stock_lines,
+                                                  :empty?).and_return false
+
+            put(:update, params:)
+
+            expect_cable_ready_redirect(response)
+          end
+        end
       end
 
       context "with no payment source" do
@@ -468,6 +490,16 @@ RSpec.describe CheckoutController, type: :controller do
         end
       end
 
+      context "with insufficient stock" do
+        it "redirects to details page" do
+          allow(order).to receive_message_chain(:insufficient_stock_lines, :empty?).and_return false
+
+          put(:update, params:)
+
+          expect_cable_ready_redirect(response)
+        end
+      end
+
       context "when accepting T&Cs is required" do
         before do
           allow(TermsOfService).to receive(:platform_terms_required?) { true }
@@ -582,17 +614,10 @@ RSpec.describe CheckoutController, type: :controller do
       )
     end
 
-    shared_examples "handling stock issues" do |step|
+    shared_examples "handling not available items" do |step|
       context "#{step} step" do
         let(:step) { step.to_s }
 
-        it "redirects when some items are out of stock" do
-          allow(order).to receive_message_chain(:insufficient_stock_lines, :empty?).and_return false
-
-          get :edit
-          expect(response).to redirect_to cart_path
-        end
-
         it "redirects when some items are not available" do
           allow(order).to receive_message_chain(:insufficient_stock_lines, :empty?).and_return true
           expect(order_cycle_distributed_variants).to receive(
@@ -605,9 +630,9 @@ RSpec.describe CheckoutController, type: :controller do
       end
     end
 
-    it_behaves_like "handling stock issues", "details"
-    it_behaves_like "handling stock issues", "payment"
-    it_behaves_like "handling stock issues", "summary"
+    it_behaves_like "handling not available items", "details"
+    it_behaves_like "handling not available items", "payment"
+    it_behaves_like "handling not available items", "summary"
   end
 
   def mock_voucher_adjustment_service
@@ -616,4 +641,10 @@ RSpec.describe CheckoutController, type: :controller do
 
     voucher_adjustment_service
   end
+
+  def expect_cable_ready_redirect(response)
+    expect(response.parsed_body).to eq(
+      [{ "url" => "/checkout/details", "operation" => "redirectTo" }].to_json
+    )
+  end
 end

spec/system/consumer/checkout/guest_spec.rb

@@ -14,15 +14,24 @@ RSpec.describe "As a consumer, I want to checkout my order" do
   let(:product) {
     create(:taxed_product, supplier_id: supplier.id, price: 10, zone:, tax_rate_amount: 0.1)
   }
+  let(:product2) {
+    create(:taxed_product, supplier_id: supplier.id, price: 15, zone:, tax_rate_amount: 0.1)
+  }
+
   let(:variant) { product.variants.first }
+  let(:variant2 ) { product2.variants.first }
   let!(:order_cycle) {
     create(:simple_order_cycle, suppliers: [supplier], distributors: [distributor],
-                                coordinator: create(:distributor_enterprise), variants: [variant])
+                                coordinator: create(:distributor_enterprise),
+                                variants: [variant, variant2])
   }
   let(:order) {
     create(:order, order_cycle:, distributor:, bill_address_id: nil,
                    ship_address_id: nil, state: "cart",
-                   line_items: [create(:line_item, variant:)])
+                   line_items: [
+                     create(:line_item, variant:),
+                     create(:line_item, variant: variant2, quantity: 3)
+                   ])
   }
 
   let(:fee_tax_rate) { create(:tax_rate, amount: 0.10, zone:, included_in_price: true) }
@@ -277,11 +286,18 @@ RSpec.describe "As a consumer, I want to checkout my order" do
   shared_examples "when a line item is out of stock" do |session, step|
     context "as a #{session} user" do
       let(:user) { create(:user) }
+
       before do
+        # Out of stock
         variant.on_demand = false
         variant.on_hand = 0
         variant.save!
 
+        # Reduced stock
+        variant2.on_demand = false
+        variant2.on_hand = 1
+        variant2.save!
+
         if session == "logged"
           login_as(user)
         end
@@ -292,7 +308,13 @@ RSpec.describe "As a consumer, I want to checkout my order" do
 
         expect(page).to have_selector 'closing', text: "Checkout now"
         within "#out-of-stock-items" do
-          expect(page).to have_content "Some items are out of stock"
+          expect(page).to have_content "Reduced stock available"
+          expect(page).to have_content(
+            "#{variant.name_to_display} - #{variant.unit_to_display} is now out of stock"
+          )
+          expect(page).to have_content(
+            "#{variant2.name_to_display} - #{variant2.unit_to_display} now only has 1 remaining"
+          )
         end
       end
     end