Reset stock for absent products in DFC catalog

app/controllers/admin/dfc_product_imports_controller.rb

@@ -58,6 +58,7 @@ module Admin
       end
 
       @count = imported.compact.count
+      @reset_count = reset_absent_variants(catalog).count
     rescue ActionController::ParameterMissing => e
       flash[:error] = e.message
       redirect_to admin_product_import_path
@@ -80,5 +81,23 @@ module Admin
         ]
       end
     end
+
+    def reset_absent_variants(catalog)
+      present_ids = catalog.products.map(&:semanticId)
+      absent_variants = @enterprise.supplied_variants
+        .includes(:semantic_links).references(:semantic_links)
+        .where.not(semantic_links: { semantic_id: present_ids })
+
+      catalog_url = FdcUrlBuilder.new(present_ids.first).catalog_url
+      absent_variants.select do |variant|
+        # Variants that were in the same catalog before:
+        variant.semantic_links.map(&:semantic_id).any? do |semantic_id|
+          FdcUrlBuilder.new(semantic_id).catalog_url == catalog_url
+        end
+      end.map do |variant|
+        variant.on_demand = false
+        variant.on_hand = 0
+      end
+    end
   end
 end

app/views/admin/dfc_product_imports/import.html.haml

@@ -5,3 +5,6 @@
 
 %p= t(".imported_products")
 = @count
+
+%p= t(".reset_products")
+= @reset_count

config/locales/en.yml

@@ -866,6 +866,7 @@ en:
       import:
         title: "DFC product catalog import"
         imported_products: "Imported products:"
+        reset_products: "Stock reset for absent products:"
     enterprise_fees:
       index:
         title: "Enterprise Fees"

spec/system/admin/dfc_product_import_spec.rb

@@ -9,6 +9,7 @@ RSpec.describe "DFC Product Import" do
   let(:user) { create(:oidc_user, owned_enterprises: [enterprise]) }
   let(:enterprise) { create(:supplier_enterprise, name: "Saucy preserves") }
   let(:source_product) { create(:product, name: "Sauce", supplier_id: enterprise.id) }
+  let(:old_product) { create(:product, name: "Best Sauce of 1995", supplier_id: enterprise.id) }
 
   before do
     login_as user
@@ -52,12 +53,21 @@ RSpec.describe "DFC Product Import" do
 
   it "imports from a FDC catalog", vcr: true do
     user.update!(oidc_account: build(:testdfc_account))
-    # One product is existing in OFN
+
+    # One current product is existing in OFN
     product_id =
       "https://env-0105831.jcloud-ver-jpe.ik-server.com/api/dfc/Enterprises/test-hodmedod/SuppliedProducts/44519466467635"
     linked_variant = source_product.variants.first
     linked_variant.semantic_links << SemanticLink.new(semantic_id: product_id)
 
+    # One outdated product still exists in OFN
+    old_product_id =
+      "https://env-0105831.jcloud-ver-jpe.ik-server.com/api/dfc/Enterprises/test-hodmedod/SuppliedProducts/445194664-1995"
+    unlinked_variant = old_product.variants.first
+    unlinked_variant.semantic_links << SemanticLink.new(semantic_id: old_product_id)
+    unlinked_variant.on_demand = true
+    unlinked_variant.on_hand = 3
+
     visit admin_product_import_path
 
     url = "https://env-0105831.jcloud-ver-jpe.ik-server.com/api/dfc/Enterprises/test-hodmedod/SuppliedProducts"
@@ -83,14 +93,18 @@ RSpec.describe "DFC Product Import" do
     expect {
       click_button "Import"
       expect(page).to have_content "Imported products: 3"
+      expect(page).to have_content "Stock reset for absent products: 1"
       linked_variant.reload
-    }.to change { enterprise.supplied_products.count }.by(2) # 1 updated, 2 new
+      unlinked_variant.reload
+    }.to change { enterprise.supplied_products.count }.by(2) # 1 updated, 2 new, 1 reset
       .and change { linked_variant.display_name }
       .and change { linked_variant.unit_value }
       # 18.85 wholesale variant price divided by 12 cans in the slab.
       .and change { linked_variant.price }.to(1.57)
       .and change { linked_variant.on_demand }.to(true)
       .and change { linked_variant.on_hand }.by(0)
+      .and change { unlinked_variant.on_demand }.to(false)
+      .and change { unlinked_variant.on_hand }.to(0)
 
     product = Spree::Product.last
     expect(product.variants[0].semantic_links).to be_present