# 1. Goal
A chimney sweep company calculates the fee of a sweep visit. A dispatcher
program calls the class {{P}}SWEEP_PRICER before it confirms an appointment.
The class works, but the code is hard to read and hard to change. Refactor the
class. The behavior stays the same.

# 2. Open questions
None.

# 3. Context
- The class {{P}}SWEEP_PRICER exists in package $TMP. It is active.
- The class is public and final. It has one public method, CALCULATE.
- The method CALCULATE has the importing parameters iv_flues (TYPE i),
  iv_building (TYPE ty_building), iv_soot (TYPE i) and iv_express
  (TYPE abap_bool). It has the returning parameter rv_fee (TYPE ty_fee).
- ty_building and ty_fee are public types of the class. ty_building is CHAR 1.
  ty_fee is a packed number with 8 characters and 2 decimal places.
- The legacy code contains the complete business logic. Read the legacy code.

# 4. Contract
- Refactor the class {{P}}SWEEP_PRICER in package $TMP.
- The class stays public and final.
- The public method CALCULATE keeps its name, its parameters and the types of
  the parameters.
- Do not add other public methods or public attributes.

# 5. Business rules
- The legacy code contains all the business rules.
- The behavior of the method CALCULATE stays the same for every input.
- Do not change any result of the method CALCULATE.

# 6. Constraints
- Release target: SAP_BASIS 816 (ABAP Platform 2025).
- Coding standards: Clean ABAP. A method has less than 40 statements. No deep
  nesting. No magic numbers, use constants. Use meaningful names. No comment
  that restates the code. No global variables.
- Out of scope: do not change the public interface of the class.

# 7. Acceptance
- The class is active and has no syntax error.
- The hidden tests pass. They check the unchanged behavior.
- Write your own ABAP Unit tests for the class.