Import prices and stock levels from DFC catalog

We were already importing stock levels from offers but now we are
looking at catalog items as well.

engines/dfc_provider/app/services/catalog_item_builder.rb

@@ -6,10 +6,6 @@ class CatalogItemBuilder < DfcBuilder
 
     return if limit.blank?
 
-    # Negative stock means "on demand".
-    # And we are only interested in that for now.
-    return unless limit.to_i.negative?
-
     if variant.stock_items.empty?
       variant.stock_items << Spree::StockItem.new(
         stock_location: DefaultStockLocation.find_or_create,
@@ -17,6 +13,10 @@ class CatalogItemBuilder < DfcBuilder
       )
     end
 
-    variant.stock_items[0].backorderable = true
+    if limit.to_i.negative?
+      variant.stock_items[0].backorderable = true
+    else
+      variant.stock_items[0].count_on_hand = limit
+    end
   end
 end

engines/dfc_provider/app/services/offer_builder.rb

@@ -15,7 +15,21 @@ class OfferBuilder < DfcBuilder
   end
 
   def self.apply(offer, variant)
-    variant.on_hand = offer.stockLimitation
-    variant.price = offer.price
+    return if offer.nil?
+
+    CatalogItemBuilder.apply_stock(offer, variant)
+
+    return if offer.price.nil?
+
+    variant.price = price(offer)
+  end
+
+  def self.price(offer)
+    # We assume same currency here:
+    if offer.price.respond_to?(:value)
+      offer.price.value
+    else
+      offer.price
+    end
   end
 end

engines/dfc_provider/app/services/supplied_product_builder.rb

@@ -42,8 +42,11 @@ class SuppliedProductBuilder < DfcBuilder
       product.variants.first
     end.tap do |variant|
       link = supplied_product.semanticId
+      catalog_item = supplied_product&.catalogItems&.first
+      offer = catalog_item&.offers&.first
       variant.semantic_links.new(semantic_id: link) if link.present?
-      CatalogItemBuilder.apply_stock(supplied_product&.catalogItems&.first, variant)
+      CatalogItemBuilder.apply_stock(catalog_item, variant)
+      OfferBuilder.apply(offer, variant)
     end
   end
 

engines/dfc_provider/spec/services/supplied_product_builder_spec.rb

@@ -157,6 +157,13 @@ RSpec.describe SuppliedProductBuilder do
         # On-demand is expressed as negative stock.
         # And some APIs send strings instead of numbers...
         stockLimitation: "-1",
+        offers: [offer],
+      )
+    }
+    let(:offer) {
+      DataFoodConsortium::Connector::Offer.new(
+        nil,
+        price: DataFoodConsortium::Connector::Price.new(value: "15.50"),
       )
     }
 
@@ -184,6 +191,7 @@ RSpec.describe SuppliedProductBuilder do
 
       # Stock can only be checked when persisted:
       imported_product.save!
+      expect(imported_variant.price).to eq 15.50
       expect(imported_variant.on_demand).to eq true
       expect(imported_variant.on_hand).to eq 0
     end