!-------------------------------------------------------------------------------

! This file is part of Code_Saturne, a general-purpose CFD tool.
!
! Copyright (C) 1998-2021 EDF S.A.
!
! This program 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 2 of the License, or (at your option) any later
! version.
!
! This program 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
! this program; if not, write to the Free Software Foundation, Inc., 51 Franklin
! Street, Fifth Floor, Boston, MA 02110-1301, USA.

!-------------------------------------------------------------------------------

!> \file turbomachinery.f90
!> \brief Module for turbomachinery computations

module turbomachinery

  !=============================================================================
  !> \defgroup at_turbomachinery Module for turbomachinery computations

  !> \addtogroup at_turbomachinery
  !> \{

  !> Type of turbomachinery computation:
  !>   none (0), frozen rotor (1), transient (2)

  integer, save :: iturbo

  !> Type of rotor/stator interface:
  !>   joint internal faces (0), coupled boundary faces (1)

  integer, save :: ityint

  !> Rotor identifier list (1:ncel)

  integer, dimension(:), pointer :: irotce

  ! Elapsed time for logging

  double precision, save :: rs_ell(2)

  ! Arrays associated to wall BC update

  double precision, dimension(:), allocatable :: coftur, hfltur

  !> \}

  !=============================================================================

  interface

    ! Interface to C function mapping some data for turbomachinery

    subroutine map_turbomachinery_model (iturbo2, ityint2) &
      bind(C, name='cs_f_map_turbomachinery_model')
      use, intrinsic :: iso_c_binding
      implicit none
      integer(c_int), intent(out) :: iturbo2, ityint2
    end subroutine map_turbomachinery_model

    !---------------------------------------------------------------------------

    ! Interface to C function mapping some data for turbomachinery

    subroutine map_turbomachinery_rotor (irotce2) &
      bind(C, name='cs_f_map_turbomachinery_rotor')
      use, intrinsic :: iso_c_binding
      implicit none
      type(c_ptr), intent(out) :: irotce2
    end subroutine map_turbomachinery_rotor

    !---------------------------------------------------------------------------

    ! Interface to C function updating mesh for turbomachinery

    subroutine turbomachinery_update_mesh(t_cur_mob, t_elapsed)            &
      bind(C, name='cs_turbomachinery_update_mesh')
      use, intrinsic :: iso_c_binding
      implicit none
      real(kind=c_double), value :: t_cur_mob
      real(kind=c_double), intent(out) :: t_elapsed
    end subroutine turbomachinery_update_mesh

    !---------------------------------------------------------------------------

    ! Interface to C function resetting face fields for turbomachinery

    subroutine turbomachinery_reinit_i_face_fields() &
      bind(C, name='cs_turbomachinery_reinit_i_face_fields')
      use, intrinsic :: iso_c_binding
      implicit none
    end subroutine turbomachinery_reinit_i_face_fields

    !---------------------------------------------------------------------------

    ! Interface to C function resizing owned cell fields for turbomachinery

    subroutine turbomachinery_resize_cell_fields() &
      bind(C, name='cs_turbomachinery_resize_cell_fields')
      use, intrinsic :: iso_c_binding
      implicit none
    end subroutine turbomachinery_resize_cell_fields

  end interface

contains

  !=============================================================================

  ! Initialization of turbomachinery module variables

  subroutine turbomachinery_init

    use, intrinsic :: iso_c_binding
    use mesh

    implicit none

    ! Local variables

    type(c_ptr) :: c_p

    ! Map turbomachinery module components to global c turbomachinery structure

    call map_turbomachinery_rotor(c_p)

    call c_f_pointer(c_p, irotce, [ncelet])

    ! Initialization of elapsed times

    rs_ell(1) = 0.d0
    rs_ell(2) = 0.d0

    ! Allocate arrays for wall velocity BC update

    if (iturbo.eq.2)  allocate(coftur(nfabor), hfltur(nfabor))

    return

  end subroutine turbomachinery_init

  !=============================================================================

  ! Sync turbomachinery module components to global c turbomachinery structure

  subroutine turbomachinery_update

    use, intrinsic :: iso_c_binding
    use mesh

    implicit none

    ! Local variables

    type(c_ptr) :: c_p

    call map_turbomachinery_rotor(c_p)

    call turbomachinery_resize_cell_fields

    call c_f_pointer(c_p, irotce, [ncelet])

    return

  end subroutine turbomachinery_update

  !=============================================================================

  ! Finalization of turbomachinery module variables

  subroutine turbomachinery_finalize

    if (iturbo.eq.2)  deallocate(coftur, hfltur)

    return

  end subroutine turbomachinery_finalize

  !=============================================================================

end module turbomachinery
