With order cycle distribution, show error message when adding a product to cart with no distribution chosen

app/controllers/spree/orders_controller_decorator.rb

@@ -28,13 +28,19 @@ Spree::OrdersController.class_eval do
 
   def populate_order_distributor
     @distributor = params[:distributor_id].present? ? Enterprise.is_distributor.find(params[:distributor_id]) : nil
+    @order_cycle = params[:order_cycle_id].present? ? OrderCycle.find(params[:order_cycle_id]) : nil
 
     if populate_valid? @distributor
       order = current_order(true)
       order.set_distributor! @distributor
 
     else
-      flash[:error] = "Please choose a distributor for this order." if @distributor.nil?
+      if populate_order_cycle_required
+        flash[:error] = "Please choose a distributor and order cycle for this order." if @distributor.nil? || @order_cycle.nil?
+      else
+        flash[:error] = "Please choose a distributor for this order." if @distributor.nil?
+      end
+
       redirect_populate_to_first_product
     end
   end
@@ -108,7 +114,7 @@ Spree::OrdersController.class_eval do
       return false unless Enterprise.distributing_product(variant.product).include? distributor
     end if params[:variants]
 
-    # -- If products in cart, distributor can't be changed
+    # -- Distributor can't be changed unless new distributor can service cart
     order = current_order(false)
     if !order.nil? && !DistributorChangeValidator.new(order).can_change_to_distributor?(distributor) 
       return false
@@ -117,6 +123,18 @@ Spree::OrdersController.class_eval do
     true
   end
 
+  # Adding product to cart requires an order cycle if product has no product distributions
+  def populate_order_cycle_required
+    populate_products.any? { |p| p.product_distributions.empty? }
+  end
+
+  def populate_products
+    # TODO: This is quite inefficient. Push to SQLland?
+    (params[:products] || []).map { |product_id, variant_id| Spree::Product.find product_id } +
+      (params[:variants] || []).map { |variant_id, quantity| Spree::Variant.find(variant_id).product }
+  end
+
+
   def redirect_populate_to_first_product
     product = if params[:products].present?
                 Spree::Product.find(params[:products].keys.first)

spec/features/consumer/add_to_cart_spec.rb

@@ -162,6 +162,27 @@ feature %q{
   end
 
   context "with order cycle distribution" do
+    scenario "adding a product to the cart with no distribution chosen" do
+      # Given a product and some distributors
+      d1 = create(:distributor_enterprise)
+      d2 = create(:distributor_enterprise)
+      p1 = create(:product)
+      p2 = create(:product)
+      create(:simple_order_cycle, :distributors => [d1], :variants => [p1.master])
+      create(:simple_order_cycle, :distributors => [d2], :variants => [p2.master])
+
+      # When I add an item to my cart without choosing a distributor or order cycle
+      visit spree.product_path p1
+      click_button 'Add To Cart'
+
+      # Then I should see an error message
+      page.should have_content "Please choose a distributor and order cycle for this order."
+
+      # And the product should not have been added to my cart
+      Spree::Order.last.should be_nil
+    end
+
+
     it "allows us to add two products from the same distributor" do
       # Given two products, each at the same distributor
       d = create(:distributor_enterprise)