# 1. Goal
Give the sales figures of each product for a period. The period is an input of the
view. A report and an OData service read the figures, so the calculation must be in
the database, in a CDS view.

# 2. Open questions
None.

# 3. Context
- Table {{P}}SALES (sales line), package $TMP. Key: DOC_ID (CHAR 10), ITEM_NO (INT4).
  Fields: PRODUCT (CHAR 10), QUANTITY (INT4), PRICE (DEC 15,2, the price of one
  unit), SOLD_ON (DATS, the date of the sale).
- The class {{P}}SEED_SALES fills {{P}}SALES with sample data. Run it if you want to
  test the view manually.

# 4. Contract
- Create the CDS view entity {{P}}I_SALES_REPORT in package $TMP.
- Input parameters, with these names and types: P_FROM (DATS), P_TO (DATS).
  The parameters have no default value.
- Elements, with these names: PRODUCT (key), TOTAL_QTY, TOTAL_AMOUNT.
- No authorization check (#NOT_REQUIRED).

# 5. Business rules
1. A sales line is in the period when SOLD_ON is not before P_FROM and not after
   P_TO. P_FROM and P_TO are part of the period.
2. Show one row for each product with at least one sales line in the period. Do not
   show a product without a sales line in the period.
3. TOTAL_QTY is the sum of QUANTITY of all sales lines of the product in the period.
4. TOTAL_AMOUNT is the sum of QUANTITY multiplied by PRICE of all sales lines of the
   product in the period, with 2 decimals.

# 6. Constraints
- Release target: 7.58.
- Coding standards: Clean ABAP.
- Out of scope: do not change {{P}}SALES and {{P}}SEED_SALES.

# 7. Acceptance
- The view is active and has no syntax error.
- The hidden tests pass.
- Write ABAP Unit tests with CL_CDS_TEST_ENVIRONMENT in a global test class.