Enhance product sorting for On-Demand items and add backorderable name support

app/controllers/admin/products_v3_controller.rb

@@ -124,11 +124,21 @@ module Admin
       @per_page = params[:per_page].presence || 15
       @q = params.permit(q: {})[:q] || { s: 'name asc' }
 
-      # Transform on_hand sorting to include backorderable_priority (on-demand) for proper ordering
+      # Transform on_hand sorting to properly handle On-Demand products:
+      #   - On-Demand products should ignore on_hand completely and sort alphabetically.
+      #   - Non-On-Demand products should continue sorting by on_hand as usual.
       if @q[:s] == 'on_hand asc'
-        @q[:s] = ['backorderable_priority asc', @q[:s]]
+        @q[:s] = [
+          'backorderable_priority asc',
+          'backorderable_name asc',
+          @q[:s]
+        ]
       elsif @q[:s] == 'on_hand desc'
-        @q[:s] = ['backorderable_priority desc', @q[:s]]
+        @q[:s] = [
+          'backorderable_priority desc',
+          'backorderable_name asc',
+          @q[:s]
+        ]
       end
     end
 
@@ -173,6 +183,7 @@ module Admin
         product_query = product_query.select(
           Arel.sql('spree_products.*'),
           Spree::Product.backorderable_priority_sql,
+          Spree::Product.backorderable_name_sql,
           Spree::Product.on_hand_sql
         )
       end

app/models/concerns/product_sort_by_stocks.rb

@@ -3,7 +3,7 @@
 module ProductSortByStocks
   extend ActiveSupport::Concern
 
-  included do
+  included do # rubocop:disable Metrics/BlockLength
     @on_hand_sql = Arel.sql("(
       SELECT COALESCE(SUM(si.count_on_hand), 0)
       FROM spree_variants v
@@ -20,8 +20,18 @@ module ProductSortByStocks
       GROUP BY v.product_id
     )")
 
+    # When a product is On-Demand (backorderable = true), return the product name.
+    # This allows alphabetical ordering inside the On-Demand group.
+    # For non-On-Demand products, return NULL so normal on_hand sorting still applies.
+    @backorderable_name_sql = Arel.sql("
+      CASE
+        WHEN (#{@backorderable_priority_sql}) THEN spree_products.name
+        ELSE NULL
+      END
+    ")
+
     class << self
-      attr_reader :on_hand_sql, :backorderable_priority_sql
+      attr_reader :on_hand_sql, :backorderable_priority_sql, :backorderable_name_sql
     end
 
     ransacker :on_hand do
@@ -31,5 +41,9 @@ module ProductSortByStocks
     ransacker :backorderable_priority do
       @backorderable_priority_sql
     end
+
+    ransacker :backorderable_name do
+      @backorderable_name_sql
+    end
   end
 end

app/models/spree/product.rb

@@ -31,7 +31,8 @@ module Spree
 
     acts_as_paranoid
 
-    searchable_attributes :meta_keywords, :sku, :on_hand, :backorderable_priority
+    searchable_attributes :meta_keywords, :sku, :on_hand, :backorderable_priority,
+                          :backorderable_name
     searchable_associations :properties, :variants
     searchable_scopes :active, :with_properties