CLASS {{P}}TOUR_PLANNER DEFINITION PUBLIC FINAL CREATE PUBLIC.
  PUBLIC SECTION.
    TYPES ty_status TYPE c LENGTH 10.
    TYPES ty_tour_id TYPE c LENGTH 4.
    TYPES ty_customer TYPE c LENGTH 10.
    TYPES ty_weight TYPE p LENGTH 8 DECIMALS 2.

    CONSTANTS:
      BEGIN OF c_status,
        ok        TYPE ty_status VALUE 'OK',
        invalid   TYPE ty_status VALUE 'INVALID',
        duplicate TYPE ty_status VALUE 'DUPLICATE',
      END OF c_status.

    TYPES:
      BEGIN OF ty_item,
        tour_id  TYPE ty_tour_id,
        stop_no  TYPE i,
        customer TYPE ty_customer,
        packages TYPE i,
        weight   TYPE ty_weight,
      END OF ty_item,
      tt_item TYPE STANDARD TABLE OF ty_item WITH EMPTY KEY,

      BEGIN OF ty_tour,
        tour_id  TYPE ty_tour_id,
        stops    TYPE i,
        packages TYPE i,
        weight   TYPE ty_weight,
      END OF ty_tour,
      tt_tour TYPE STANDARD TABLE OF ty_tour WITH EMPTY KEY.

    METHODS add_item
      IMPORTING iv_tour_id       TYPE ty_tour_id
                iv_stop_no       TYPE i
                iv_customer      TYPE ty_customer
                iv_packages      TYPE i
                iv_weight        TYPE ty_weight
      RETURNING VALUE(rv_status) TYPE ty_status.

    METHODS remove_tour
      IMPORTING iv_tour_id      TYPE ty_tour_id
      RETURNING VALUE(rv_count) TYPE i.

    METHODS items
      RETURNING VALUE(rt_item) TYPE tt_item.

    METHODS stops_of_tour
      IMPORTING iv_tour_id     TYPE ty_tour_id
      RETURNING VALUE(rt_item) TYPE tt_item.

    METHODS find_stop
      IMPORTING iv_tour_id     TYPE ty_tour_id
                iv_stop_no     TYPE i
      RETURNING VALUE(rs_item) TYPE ty_item.

    METHODS tour_summary
      RETURNING VALUE(rt_tour) TYPE tt_tour.

  PRIVATE SECTION.
    TYPES tt_stop TYPE SORTED TABLE OF ty_item WITH UNIQUE KEY tour_id stop_no.

    DATA mt_stop TYPE tt_stop.

    METHODS is_invalid
      IMPORTING iv_tour_id        TYPE ty_tour_id
                iv_stop_no        TYPE i
                iv_packages       TYPE i
                iv_weight         TYPE ty_weight
      RETURNING VALUE(rv_invalid) TYPE abap_bool.
ENDCLASS.


CLASS {{P}}TOUR_PLANNER IMPLEMENTATION.
  METHOD add_item.
    IF is_invalid( iv_tour_id  = iv_tour_id
                   iv_stop_no  = iv_stop_no
                   iv_packages = iv_packages
                   iv_weight   = iv_weight ) = abap_true.
      rv_status = c_status-invalid.
      RETURN.
    ENDIF.

    DATA(ls_stop) = VALUE ty_item( tour_id  = iv_tour_id
                                   stop_no  = iv_stop_no
                                   customer = iv_customer
                                   packages = iv_packages
                                   weight   = iv_weight ).
    INSERT ls_stop INTO TABLE mt_stop.

    IF sy-subrc <> 0.
      rv_status = c_status-duplicate.
      RETURN.
    ENDIF.

    rv_status = c_status-ok.
  ENDMETHOD.

  METHOD remove_tour.
    DELETE mt_stop WHERE tour_id = iv_tour_id.
    rv_count = sy-dbcnt.
  ENDMETHOD.

  METHOD items.
    rt_item = mt_stop.
  ENDMETHOD.

  METHOD stops_of_tour.
    rt_item = VALUE #( FOR ls_stop IN mt_stop WHERE ( tour_id = iv_tour_id ) ( ls_stop ) ).
  ENDMETHOD.

  METHOD find_stop.
    READ TABLE mt_stop WITH KEY tour_id = iv_tour_id
                                 stop_no = iv_stop_no INTO rs_item.
    IF sy-subrc <> 0.
      CLEAR rs_item.
    ENDIF.
  ENDMETHOD.

  METHOD tour_summary.
    DATA lt_tour TYPE SORTED TABLE OF ty_tour WITH UNIQUE KEY tour_id.

    LOOP AT mt_stop INTO DATA(ls_stop).
      READ TABLE lt_tour WITH KEY tour_id = ls_stop-tour_id ASSIGNING FIELD-SYMBOL(<ls_tour>).
      IF sy-subrc <> 0.
        INSERT VALUE ty_tour( tour_id = ls_stop-tour_id )
               INTO TABLE lt_tour ASSIGNING <ls_tour>.
      ENDIF.
      <ls_tour>-stops    = <ls_tour>-stops + 1.
      <ls_tour>-packages = <ls_tour>-packages + ls_stop-packages.
      <ls_tour>-weight   = <ls_tour>-weight + ls_stop-weight.
    ENDLOOP.

    rt_tour = lt_tour.
  ENDMETHOD.

  METHOD is_invalid.
    rv_invalid = xsdbool( iv_tour_id IS INITIAL
                          OR iv_stop_no < 1
                          OR iv_packages < 0
                          OR iv_weight < 0 ).
  ENDMETHOD.
ENDCLASS.