REPORT {{p}}subs_sum.

TYPES: BEGIN OF ty_line,
         magazine TYPE {{p}}subs-magazine,
         num_subs TYPE i,
         revenue  TYPE {{p}}subs-monthly_fee,
       END OF ty_line.
TYPES tt_line TYPE STANDARD TABLE OF ty_line WITH DEFAULT KEY.
TYPES tt_magazine TYPE RANGE OF {{p}}subs-magazine.

DATA gv_magazine TYPE {{p}}subs-magazine.

PARAMETERS p_from TYPE d OBLIGATORY.
SELECT-OPTIONS s_mag FOR gv_magazine.

CLASS lcl_report DEFINITION FINAL.
  PUBLIC SECTION.
    CLASS-METHODS select_totals
      IMPORTING iv_from         TYPE d
                it_magazine     TYPE tt_magazine
      RETURNING VALUE(rt_lines) TYPE tt_line.
    CLASS-METHODS keep_regulars
      IMPORTING it_lines        TYPE tt_line
      RETURNING VALUE(rt_lines) TYPE tt_line.
    CLASS-METHODS display
      CHANGING ct_lines TYPE tt_line.
ENDCLASS.

CLASS lcl_report IMPLEMENTATION.
  METHOD select_totals.
    SELECT magazine COUNT( * ) AS num_subs SUM( monthly_fee ) AS revenue
      FROM {{p}}subs
      INTO CORRESPONDING FIELDS OF TABLE rt_lines
      WHERE sub_status = 'A'
        AND start_date >= iv_from
        AND magazine IN it_magazine
      GROUP BY magazine.
  ENDMETHOD.

  METHOD keep_regulars.
    DATA ls_line TYPE ty_line.
    LOOP AT it_lines INTO ls_line.
      IF ls_line-num_subs >= 2.
        APPEND ls_line TO rt_lines.
      ENDIF.
    ENDLOOP.
    SORT rt_lines BY revenue DESCENDING.
  ENDMETHOD.

  METHOD display.
    DATA: lo_alv   TYPE REF TO cl_salv_table,
          lo_error TYPE REF TO cx_salv_msg.
    TRY.
        cl_salv_table=>factory(
          IMPORTING r_salv_table = lo_alv
          CHANGING  t_table      = ct_lines ).
        lo_alv->display( ).
      CATCH cx_salv_msg INTO lo_error.
        MESSAGE lo_error TYPE 'I' DISPLAY LIKE 'E'.
    ENDTRY.
  ENDMETHOD.
ENDCLASS.

START-OF-SELECTION.
  DATA gt_lines TYPE tt_line.
  gt_lines = lcl_report=>select_totals( iv_from = p_from it_magazine = s_mag[] ).
  gt_lines = lcl_report=>keep_regulars( gt_lines ).
  lcl_report=>display( CHANGING ct_lines = gt_lines ).

CLASS ltc_report DEFINITION FINAL FOR TESTING DURATION SHORT RISK LEVEL HARMLESS.
  PRIVATE SECTION.
    METHODS removes_small_groups FOR TESTING.
    METHODS sorts_by_revenue FOR TESTING.
ENDCLASS.

CLASS ltc_report IMPLEMENTATION.
  METHOD removes_small_groups.
    DATA: lt_lines TYPE tt_line,
          lt_kept  TYPE tt_line,
          ls_line  TYPE ty_line.
    ls_line-magazine = 'SMALL'.
    ls_line-num_subs = 1.
    ls_line-revenue = 10.
    APPEND ls_line TO lt_lines.
    ls_line-magazine = 'BIG'.
    ls_line-num_subs = 2.
    ls_line-revenue = 20.
    APPEND ls_line TO lt_lines.
    lt_kept = lcl_report=>keep_regulars( lt_lines ).
    cl_abap_unit_assert=>assert_equals( exp = 1 act = lines( lt_kept ) ).
    READ TABLE lt_kept INTO ls_line INDEX 1.
    cl_abap_unit_assert=>assert_equals( exp = 'BIG' act = ls_line-magazine ).
  ENDMETHOD.

  METHOD sorts_by_revenue.
    DATA: lt_lines TYPE tt_line,
          lt_kept  TYPE tt_line,
          ls_line  TYPE ty_line.
    ls_line-magazine = 'LOW'.
    ls_line-num_subs = 2.
    ls_line-revenue = 10.
    APPEND ls_line TO lt_lines.
    ls_line-magazine = 'HIGH'.
    ls_line-num_subs = 2.
    ls_line-revenue = 30.
    APPEND ls_line TO lt_lines.
    lt_kept = lcl_report=>keep_regulars( lt_lines ).
    READ TABLE lt_kept INTO ls_line INDEX 1.
    cl_abap_unit_assert=>assert_equals( exp = 'HIGH' act = ls_line-magazine ).
  ENDMETHOD.
ENDCLASS.