!-*- mode: F90 -*-!
!------------------------------------------------------------!
! Copyright (C) 2026 Wannier Developer Group                 !
!                                                            !
! This library is free software; you can redistribute it     !
! and/or modify it under the terms of the GNU Lesser General !
! Public License as published by the Free Software           !
! Foundation; either version 2.1 of the License, or (at your !
! option) any later version.                                 !
!                                                            !
! This library 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 Lesser General Public License for    !
! more details.                                              !
!                                                            !
! You should have received a copy of the GNU Lesser General  !
! Public License along with this library; if not, see        !
! <https://www.gnu.org/licenses/>.                           !
!                                                            !
! The webpage of the Wannier90 code is                       !
! <https://www.wannier.org>.                                 !
!                                                            !
! The Wannier90 code is hosted on GitHub                     !
! <https://github.com/wannier-developers/wannier90>          !
!------------------------------------------------------------!

module w90_error_base
  !! Module to handle errors

  implicit none

  public

  !! Codify error state with integer code and human readable string
  type w90_error_type
    integer :: code
    character(len=128) :: message
#ifdef W90DEV
  contains
    final :: untrapped_error
#endif
  end type w90_error_type

  integer, parameter :: code_remote = -99 ! special code for error triggered by other mpi rank
  integer, parameter :: code_deactivated = -888 ! special code for error triggered by other mpi rank

contains

  subroutine untrapped_error(err)
    type(w90_error_type), intent(in) :: err
    ! this routine should never be called, so write to stderr and call "stop" in desparation
    if (err%code == code_deactivated) return
    write (0, *) "UNTRAPPED ERROR: ", err%code
    write (0, *) "UNTRAPPED ERROR: ", err%message
    stop
  end subroutine untrapped_error

  subroutine set_base_error(err, mesg, code)
    type(w90_error_type), allocatable, intent(out) :: err
    character(len=*), intent(in) :: mesg
    integer, intent(in) :: code
    allocate (err)
    err%message = trim(mesg)
    err%code = code
  end subroutine set_base_error

  ! the following is required by subroutines of the comms module
  subroutine recv_error(err)
    type(w90_error_type), allocatable, intent(out) :: err
    allocate (err)
    err%code = code_remote
  end subroutine recv_error

end module w90_error_base