!> @file user_init_flight_mod.f90
!--------------------------------------------------------------------------------------------------!
! This file is part of the PALM model system.
!
! PALM is free software: you can redistribute it and/or modify it under the terms of the GNU General
! Public License as published by the Free Software Foundation, either version 3 of the License, or
! (at your option) any later version.
!
! PALM is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the
! implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
! Public License for more details.
!
! You should have received a copy of the GNU General Public License along with PALM. If not, see
! <http://www.gnu.org/licenses/>.
!
! Copyright 1997-2021 Leibniz Universitaet Hannover
!--------------------------------------------------------------------------------------------------!
!
!
! Description:
! ------------
!> Initialization of user-defined flight measurements.
!>
!> @todo Integrate into user_module when circular dependencies has been vanished.
!--------------------------------------------------------------------------------------------------!
 MODULE user_init_flight_mod

    USE control_parameters

    USE indices

    USE kinds

!    USE netcdf_interface,                                                                          &
!        ONLY: dofl_label,                                                                          &
!              dofl_unit

    USE user

    IMPLICIT NONE

    PUBLIC user_init_flight

    INTERFACE user_init_flight
       MODULE PROCEDURE user_init_flight
    END INTERFACE user_init_flight

    CONTAINS

! Description:
! ------------
!> Execution of user-defined initialization for flight measurements.
!--------------------------------------------------------------------------------------------------!
 SUBROUTINE user_init_flight( init, k, id, label_leg )

    CHARACTER(LEN=10), OPTIONAL ::  label_leg     !< label of the respective leg

    INTEGER(iwp), OPTIONAL                ::  id  !< variable index
    INTEGER(iwp), OPTIONAL, INTENT(INOUT) ::  k   !< index for respective variable and leg

    LOGICAL ::  init  !< variable to recognize initial call

!
!-- Following statements are added to avoid compiler warnings about unused variables. Please remove.
    IF ( PRESENT( id )        )  CONTINUE
    IF ( PRESENT( k )         )  CONTINUE
    IF ( PRESENT( label_leg ) )  CONTINUE

!
!-- Sample for user-defined flight-time series.
!-- For each quantity you have to give a label and a unit, which will be used for the output into
!-- NetCDF file. They must not contain more than twenty characters.


    IF ( init )  THEN
!
!--    The number of user-defined quantity has to be increased appropriately.
!--    In the following example, 2 user-defined quantities are added.
!        num_var_fl_user = num_var_fl_user + 2

       init = .FALSE.

    ELSE

!
!--    Please add the respective number of new variables as following:

!        SELECT CASE ( id )
!
!           CASE ( 1 )
!              dofl_label(k)   = TRIM(label_leg) // '_' // 'abs_u'
!              dofl_unit(k)    = 'm/s'
!              k               = k + 1
!
!           CASE ( 2 )
!
!              dofl_label(k)   = TRIM(label_leg) // '_' // 'abs_v'
!              dofl_unit(k)    = 'm/s'
!              k               = k + 1
!
!        END SELECT

    ENDIF

 END SUBROUTINE user_init_flight
 
 END MODULE user_init_flight_mod