Sale Coupon Product Management

This module adds a "program category" concept to product categories. On a product category form you can tick that the category is meant for promotion programs, and then choose whether products in it can be sold, whether they use a fixed discount amount, and whether the category is the default one for promotions applied on the next order.

On a sale coupon or promotion program form, a new "Product Data" group appears. There you pick the program category (mandatory), optionally force a product reference code, and choose whether you want to select the reward product yourself. If you do not choose one, Odoo automatically creates a service product for the reward line, puts it in the chosen category, sets its price to zero, and keeps its name, category, sale status and price aligned with the program. If you do choose a product, it must belong to the selected category, and the same reward product cannot be used in two different programs.

Business rules are enforced: a category flagged for fixed-amount discounts requires the program reward type to be "discount" with discount type "Fixed Amount"; products in a program category must have the "Can be sold" value matching the category setting; and on such products the price and sale status fields become read-only. When a promotion applies on the next order, the default program category is filled in automatically.