# 1. Goal
Check if a vehicle may board a ferry crossing. A loading planner calls the check
before it adds the vehicle to the loading list. The check reports the first reason
that stops the loading.

# 2. Open questions
None.

# 3. Context
- The interface {{P}}IF_FERRY_REASON exists in package $TMP. It is active.
- The interface has the type TY_REASON (CHAR 12) and the constant structure
  C_REASON with the components PLATE, CATEGORY, WEIGHT, SIZE, HAZARD, HEIGHT,
  WEIGHT_LIMIT and LENGTH_LIMIT.
- A vehicle has a plate, a category, a weight, a length, a height and a hazard
  flag.

# 4. Contract
- Create the class {{P}}CX_FERRY_ERROR in package $TMP.
  - The class is public, final and inherits from CX_STATIC_CHECK.
  - The class has the public read-only attribute REASON of type
    {{P}}IF_FERRY_REASON=>TY_REASON.
  - The class has a public constructor with the importing parameter IV_REASON of
    type {{P}}IF_FERRY_REASON=>TY_REASON. The constructor stores IV_REASON in
    REASON.
  - Do not add other public components.
- Create the class {{P}}FERRY_LOAD_CHECK in package $TMP.
  - The class is public, final and has a public constructor without parameters.
  - The class has the public type TY_VEHICLE with the components PLATE (type c
    length 10), CATEGORY (type c length 1), WEIGHT_KG (type i), LENGTH_CM (type
    i), HEIGHT_CM (type i) and HAZARD (type abap_bool).
  - The class has the public method CHECK_VEHICLE with the importing parameter
    IS_VEHICLE of type TY_VEHICLE and the addition RAISING {{P}}CX_FERRY_ERROR.
  - The class has the public method CHECK_LOADING with the importing parameters
    IS_VEHICLE of type TY_VEHICLE, IV_FREE_WEIGHT of type i, IV_FREE_LENGTH of
    type i and IV_MAX_HEIGHT of type i, and the addition RAISING
    {{P}}CX_FERRY_ERROR.
  - Do not add other public methods.

# 5. Business rules
CHECK_VEHICLE applies the rules 1 to 5 in this sequence. CHECK_LOADING first calls
CHECK_VEHICLE and then applies the rules 6 to 8 in this sequence. The first rule
that fails raises the exception {{P}}CX_FERRY_ERROR with the reason of the rule.
1. Plate: remove all spaces from the plate and convert the letters to upper case.
   If the result is empty or contains a character that is not a letter A to Z, a
   digit 0 to 9 or a hyphen, the reason is PLATE.
2. Category: the category must be C, V, T or B. Else the reason is CATEGORY.
3. Weight: the weight must be greater than 0. Else the reason is WEIGHT.
4. Size: the length and the height must both be greater than 0. Else the reason
   is SIZE.
5. Hazard: if the hazard flag is true and the category is not T, the reason is
   HAZARD.
6. Height: if the height of the vehicle is greater than IV_MAX_HEIGHT, the reason
   is HEIGHT.
7. Weight limit: if the weight of the vehicle is greater than IV_FREE_WEIGHT, the
   reason is WEIGHT_LIMIT.
8. Length limit: if the length of the vehicle is greater than IV_FREE_LENGTH, the
   reason is LENGTH_LIMIT.
If no rule fails, the method returns without an exception.

# 6. Constraints
- Release target: 8.16.
- Coding standards: Clean ABAP. Method length below 40 statements. No global
  variables. No comment that restates the code.
- Out of scope: do not change {{P}}IF_FERRY_REASON.

# 7. Acceptance
- The classes are active and have no syntax error.
- The hidden tests pass.
- Write your own ABAP Unit tests for {{P}}FERRY_LOAD_CHECK.