Best Price Wins

Best Price Wins

Every ERP eventually grows a pricing table nobody fully trusts: a special deal for one customer, a rate card for the wholesale group, a general price list, seasonal promos with start and end dates, and bulk discounts from 50 units. On any given order line, several of these rules apply at once — and the price engine must pick one, the same one, every time. Business Central's own price calculation is exactly this kind of waterfall; you are building its deterministic core.

Requirements

The starter ships an enum named "Price Rule Source Type" (values "All Customers", "Customer Group", Customer) and a table named "Price Rule" — keep their names, values, fields and primary key exactly as they are, because the grading tests write rows into the table directly:

Complete the codeunit named "Price Waterfall" with one public procedure:

procedure FindBestPrice(ItemNo: Code[20]; CustomerNo: Code[20]; CustomerGroupCode: Code[20]; Quantity: Decimal; OrderDate: Date; var UnitPrice: Decimal): Boolean

A rule applies to a request only when all four checks hold:

1. Its "Item No." equals ItemNo.
2. Its source matches: a Customer rule applies when its "Source No." equals CustomerNo; a "Customer Group" rule applies when its "Source No." equals CustomerGroupCode — a blank CustomerGroupCode means the customer belongs to no group, so group rules never apply then; an "All Customers" rule applies to every request.