FUNCTION {{p}}mush_harvest
  IMPORTING
    iv_room_a TYPE string
    iv_room_b TYPE string
  EXPORTING
    ev_total_kg TYPE decfloat34
    ev_room_count TYPE i
    ev_top_grade TYPE char1
  EXCEPTIONS
    no_stock.

  DATA lt_rows TYPE STANDARD TABLE OF {{P}}HARVEST.
  DATA lt_stock TYPE SORTED TABLE OF {{P}}HARVEST WITH UNIQUE KEY room_id grade.
  DATA lt_grade TYPE SORTED TABLE OF {{P}}HARVEST WITH UNIQUE KEY grade.
  DATA lv_room TYPE {{P}}HARVEST-room_id.
  DATA lv_best TYPE {{P}}HARVEST-weight_kg.

  SELECT room_id, grade, batch_no, weight_kg
    FROM {{P}}HARVEST
    WHERE room_id <> ''
      AND grade IN ( 'A', 'B', 'C' )
      AND weight_kg > 0
      AND ( room_id = @iv_room_a OR room_id = @iv_room_b )
    INTO TABLE @lt_rows.

  IF lt_rows IS INITIAL.
    RAISE no_stock.
  ENDIF.

  LOOP AT lt_rows ASSIGNING FIELD-SYMBOL(<ls_row>).
    ev_total_kg = ev_total_kg + <ls_row>-weight_kg.
    READ TABLE lt_stock ASSIGNING FIELD-SYMBOL(<ls_stock>)
      WITH TABLE KEY room_id = <ls_row>-room_id grade = <ls_row>-grade.
    IF sy-subrc = 0.
      <ls_stock>-weight_kg = <ls_stock>-weight_kg + <ls_row>-weight_kg.
    ELSE.
      INSERT <ls_row> INTO TABLE lt_stock.
    ENDIF.
    READ TABLE lt_grade ASSIGNING FIELD-SYMBOL(<ls_grade>)
      WITH TABLE KEY grade = <ls_row>-grade.
    IF sy-subrc = 0.
      <ls_grade>-weight_kg = <ls_grade>-weight_kg + <ls_row>-weight_kg.
    ELSE.
      INSERT <ls_row> INTO TABLE lt_grade.
    ENDIF.
  ENDLOOP.

  LOOP AT lt_stock INTO DATA(ls_stock).
    IF ls_stock-room_id <> lv_room.
      ev_room_count = ev_room_count + 1.
      lv_room = ls_stock-room_id.
    ENDIF.
  ENDLOOP.

  LOOP AT lt_grade INTO DATA(ls_grade).
    IF ls_grade-weight_kg > lv_best.
      lv_best = ls_grade-weight_kg.
      ev_top_grade = ls_grade-grade.
    ENDIF.
  ENDLOOP.

ENDFUNCTION.