Add sorting by stock levels using ransacker and update locale for 'on_hand' header

app/controllers/admin/products_v3_controller.rb

@@ -123,6 +123,13 @@ module Admin
       @page = params[:page].presence || 1
       @per_page = params[:per_page].presence || 15
       @q = params.permit(q: {})[:q] || { s: 'name asc' }
+
+      # Transform on_hand sorting to include backorderable_priority for proper ordering
+      if @q[:s] == 'on_hand asc'
+        @q[:s] = ['backorderable_priority asc', @q[:s]]
+      elsif @q[:s] == 'on_hand desc'
+        @q[:s] = ['backorderable_priority desc', @q[:s]]
+      end
     end
 
     def producers
@@ -155,8 +162,22 @@ module Admin
       product_query = OpenFoodNetwork::Permissions.new(spree_current_user)
         .editable_products.merge(product_scope_with_includes).ransack(ransack_query).result
 
-      @pagy, @products = pagy(product_query.order(:name), limit: @per_page, page: @page,
-                                                          size: [1, 2, 2, 1])
+      # Postgres requires ORDER BY expressions to appear in the SELECT list when using DISTINCT.
+      # If the current ransack sort uses the computed stock columns, include them in the select
+      # so the generated COUNT/DISTINCT query is valid.
+      sort_columns = Array(@q && @q[:s]).flatten
+      if sort_columns.any? { |s|
+           s.to_s.include?('on_hand') || s.to_s.include?('backorderable_priority')
+         }
+
+        product_query = product_query.select(
+          Arel.sql('spree_products.*'),
+          Spree::Product.backorderable_priority_sql,
+          Spree::Product.on_hand_sql
+        )
+      end
+
+      @pagy, @products = pagy(product_query, limit: @per_page, page: @page, size: [1, 2, 2, 1])
     end
 
     def product_scope

app/models/concerns/product_sort_by_stocks.rb

@@ -0,0 +1,37 @@
+# frozen_string_literal: true
+
+module ProductSortByStocks
+  extend ActiveSupport::Concern
+
+  included do
+    @on_hand_sql = Arel.sql("(
+      SELECT COALESCE(SUM(si.count_on_hand), 0)
+      FROM spree_variants v
+      JOIN spree_stock_items si ON si.variant_id = v.id
+      WHERE v.product_id = spree_products.id
+      GROUP BY v.product_id
+    )")
+
+    @backorderable_priority_sql = Arel.sql("(
+      SELECT CASE WHEN BOOL_OR(si.backorderable) = true THEN 1 ELSE 0 END
+      FROM spree_variants v
+      JOIN spree_stock_items si ON si.variant_id = v.id
+      WHERE v.product_id = spree_products.id
+      GROUP BY v.product_id
+    )")
+
+    class << self
+      attr_reader :on_hand_sql, :backorderable_priority_sql
+    end
+
+    # Ransacker for ordering by stock levels
+    ransacker :on_hand do
+      @on_hand_sql
+    end
+
+    # Ransacker for backorderable status (used for complex sorting)
+    ransacker :backorderable_priority do
+      @backorderable_priority_sql
+    end
+  end
+end

app/models/spree/product.rb

@@ -19,6 +19,7 @@ require 'open_food_network/property_merge'
 module Spree
   class Product < ApplicationRecord
     include LogDestroyPerformer
+    include ProductSortByStocks
 
     self.belongs_to_required_by_default = false
     # These columns have been moved to variant. Currently this is only for documentation purposes,
@@ -30,7 +31,7 @@ module Spree
 
     acts_as_paranoid
 
-    searchable_attributes :meta_keywords, :sku
+    searchable_attributes :meta_keywords, :sku, :on_hand, :backorderable_priority
     searchable_associations :properties, :variants
     searchable_scopes :active, :with_properties
 
@@ -168,19 +169,6 @@ module Spree
     scope :by_producer, -> { joins(variants: :supplier).order('enterprises.name') }
     scope :by_name, -> { order('spree_products.name') }
 
-    # Scope for ordering by stock levels
-    scope :order_by_stock, lambda { |direction = :asc|
-      b_value = direction != :asc
-      on_hand_direction = direction == :asc ? 'ASC' : 'DESC'
-
-      joins(variants: :stock_items)
-        .group('spree_products.id, spree_products.name')
-        .order(
-          Arel.sql("CASE WHEN BOOL_OR(spree_stock_items.backorderable) = #{b_value} THEN 1 END"),
-          Arel.sql("SUM(spree_stock_items.count_on_hand) #{on_hand_direction}")
-        )
-    }
-
     scope :managed_by, lambda { |user|
       if user.admin?
         where(nil)

config/locales/en.yml

@@ -4744,6 +4744,7 @@ See the %{link} to find out more about %{sitename}'s features and to start using
           terms_of_service: "Terms of Service"
         sortable_header:
           name: "Name"
+          on_hand: "On Hand"
           number: "Number"
           completed_at: "Completed At"
           state: "State"