CLASS {{p}}departure_planner DEFINITION PUBLIC FINAL CREATE PUBLIC.
  PUBLIC SECTION.
    TYPES ty_stop  TYPE c LENGTH 4.
    TYPES ty_line  TYPE c LENGTH 6.
    TYPES ty_depot TYPE c LENGTH 4.
    TYPES ty_time  TYPE t.
    TYPES:
      BEGIN OF ty_departure,
        stop   TYPE ty_stop,
        line   TYPE ty_line,
        depart TYPE ty_time,
        depot  TYPE ty_depot,
      END OF ty_departure,
      tt_departures TYPE STANDARD TABLE OF ty_departure WITH EMPTY KEY.

    METHODS constructor.
    METHODS add_depot
      IMPORTING iv_depot      TYPE ty_depot
                it_departures TYPE tt_departures.
    METHODS next_departure
      IMPORTING iv_stop             TYPE ty_stop
                iv_from             TYPE ty_time
      RETURNING VALUE(rs_departure) TYPE ty_departure.
    METHODS departures_at_stop
      IMPORTING iv_stop              TYPE ty_stop
      RETURNING VALUE(rt_departures) TYPE tt_departures.
    METHODS count
      RETURNING VALUE(rv_count) TYPE i.

  PRIVATE SECTION.
    TYPES tt_store TYPE SORTED TABLE OF ty_departure
                       WITH UNIQUE KEY stop depart line.
    DATA mt_store TYPE tt_store.

    METHODS first_index_of_stop
      IMPORTING iv_stop         TYPE ty_stop
      RETURNING VALUE(rv_index) TYPE i.
ENDCLASS.


CLASS {{p}}departure_planner IMPLEMENTATION.
  METHOD constructor.
    CLEAR mt_store.
  ENDMETHOD.

  METHOD add_depot.
    LOOP AT it_departures INTO DATA(ls_departure).
      DATA(ls_store) = ls_departure.
      ls_store-depot = iv_depot.
      INSERT ls_store INTO TABLE mt_store.
    ENDLOOP.
  ENDMETHOD.

  METHOD next_departure.
    DATA(lv_start) = first_index_of_stop( iv_stop ).
    IF lv_start = 0.
      RETURN.
    ENDIF.
    LOOP AT mt_store INTO DATA(ls_departure) FROM lv_start.
      IF ls_departure-stop = iv_stop.
        EXIT.
      ENDIF.
      IF ls_departure-depart >= iv_from.
        rs_departure = ls_departure.
        RETURN.
      ENDIF.
    ENDLOOP.
  ENDMETHOD.

  METHOD departures_at_stop.
    DATA(lv_start) = first_index_of_stop( iv_stop ).
    IF lv_start = 0.
      RETURN.
    ENDIF.
    LOOP AT mt_store INTO DATA(ls_departure) FROM lv_start.
      IF ls_departure-stop <> iv_stop.
        EXIT.
      ENDIF.
      APPEND ls_departure TO rt_departures.
    ENDLOOP.
  ENDMETHOD.

  METHOD count.
    rv_count = lines( mt_store ).
  ENDMETHOD.

  METHOD first_index_of_stop.
    READ TABLE mt_store TRANSPORTING NO FIELDS WITH KEY stop = iv_stop.
    IF sy-subrc = 0.
      rv_index = sy-tabix.
    ENDIF.
  ENDMETHOD.
ENDCLASS.