From baf91d73ad5aac2ffb6175124b8e8ca7d89af2f0 Mon Sep 17 00:00:00 2001
From: Tomasz Stolarczyk <stolarczykt@gmail.com>
Date: Tue, 24 Sep 2024 23:44:50 +0200
Subject: [PATCH] Move increment/decrement stock level to dedicated service

---
 .../app/controllers/orders_controller.rb         |  6 +++---
 .../app/models/inventory/product_service.rb      | 16 ++++++++++++++++
 2 files changed, 19 insertions(+), 3 deletions(-)
 create mode 100644 rails_application/app/models/inventory/product_service.rb

diff --git a/rails_application/app/controllers/orders_controller.rb b/rails_application/app/controllers/orders_controller.rb
index cbc88589..08bccd19 100644
--- a/rails_application/app/controllers/orders_controller.rb
+++ b/rails_application/app/controllers/orders_controller.rb
@@ -77,7 +77,7 @@ def add_item
 
     @order = Order.find(params[:id])
     @order.add_item(product)
-    product.decrement!(:stock_level)
+    Inventory::ProductService.new.decrement_stock_level(product.id)
     @order.save!
 
     redirect_to edit_order_path(params[:id])
@@ -87,7 +87,7 @@ def remove_item
     product = Product.find(params[:product_id])
     @order = Order.find(params[:id])
     @order.remove_item(product)
-    product.increment!(:stock_level)
+    Inventory::ProductService.new.increment_stock_level(product.id)
     @order.save!
 
     redirect_to edit_order_path(params[:id])
@@ -113,7 +113,7 @@ def expire
       .where(status: "Draft")
       .find_each do |order|
       order.order_items.each do |item|
-        item.product.increment!(:stock_level)
+        Inventory::ProductService.new.increment_stock_level(item.product.id)
       end
       order.status = "Expired"
       order.save!
diff --git a/rails_application/app/models/inventory/product_service.rb b/rails_application/app/models/inventory/product_service.rb
new file mode 100644
index 00000000..8a9defcf
--- /dev/null
+++ b/rails_application/app/models/inventory/product_service.rb
@@ -0,0 +1,16 @@
+# frozen_string_literal: true
+
+module Inventory
+  class ProductService
+
+    def decrement_stock_level(product_id)
+      product = ::Product.find(product_id)
+      product.decrement!(:stock_level)
+    end
+
+    def increment_stock_level(product_id)
+      product = ::Product.find(product_id)
+      product.increment!(:stock_level)
+    end
+  end
+end