!!  Copyright (C)  Stichting Deltares, 2012-2021.
!!
!!  This program is free software: you can redistribute it and/or modify
!!  it under the terms of the GNU General Public License version 3,
!!  as published by the Free Software Foundation.
!!
!!  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, see <http://www.gnu.org/licenses/>.
!!
!!  contact: delft3d.support@deltares.nl
!!  Stichting Deltares
!!  P.O. Box 177
!!  2600 MH Delft, The Netherlands
!!
!!  All indications and logos of, and references to registered trademarks
!!  of Stichting Deltares remain the property of Stichting Deltares. All
!!  rights reserved.

      program delpar_main

      implicit none

      integer                          :: argc
      character(len=256)               :: filepar
      character(len=256)               :: fileerr
      character(len=256)               :: filename
      character(len=256)               :: runid
      logical                          :: exi
      integer(4)                       :: ioerr
      integer(4)                       :: i
      integer(4)                       :: imdp
      integer(4)                       :: iinp
      integer(4)                       :: lunfil

!     
!     Retrieve input filename, either from a file called 'runid.par' or as a command line argument
!     
      fileerr = "delpar_error.log"
      argc = command_argument_count()
      if ( argc == 0 ) then
         filepar = "runid.par"
         inquire ( file = filepar , exist = exi )
         if ( exi ) then
            open(newunit=lunfil,file=filepar)
            read(lunfil,'(a)',iostat=ioerr) runid
            close(lunfil)
            if ( ioerr .ne. 0 .or. runid.eq.' ') then
               open(newunit=lunfil,file=fileerr,status='replace')
               write(*,'(a)',iostat=ioerr) 'ERROR: No commandline argument, and "runid.par" does not contain a runid'
               write(lunfil,'(a)',iostat=ioerr) 'ERROR: No commandline argument, and "runid.par" does not contain a runid'
               close(lunfil)
               call stop_exit(1)
            endif
            imdp=index(runid, ".mdp") 
            iinp=index(runid, ".inp")
            if(imdp==0.and.iinp.eq.0) then
               filename = trim(runid)//".mdp"
            else if (iinp.ne.0) then
               filename = runid(1:iinp-1)//".mdp"
            else
               filename = trim(runid)
            end if
            inquire ( file = filename , exist = exi )
            if (.not. exi ) then
               open(newunit=lunfil,file=fileerr,status='replace')
               write(*,'(3a)',iostat=ioerr) 'ERROR: Input file from "runid.par" named "', trim(filename), '" was not found'
               write(lunfil,'(3a)',iostat=ioerr) 'ERROR: Input file from "runid.par" named "', trim(filename), '" was not found'
               close(lunfil)
               call stop_exit(1)
            endif
         else
            open(newunit=lunfil,file=fileerr,status='replace')
            write(*,'(a)',iostat=ioerr) 'ERROR: No commandline argument, and "runid.par" not found'
            write(lunfil,'(a)',iostat=ioerr) 'ERROR: No commandline argument, and "runid.par" not found'
            close(lunfil)
            call stop_exit(1)
         endif
      else
         call get_command_argument(1, filename)
         imdp=index(filename, ".mdp") 
         iinp=index(filename, ".inp")
         if(imdp==0.and.iinp.eq.0) then
            filename = trim(filename)//".mdp"
         else if (iinp.ne.0) then
            filename = filename(1:iinp-1)//".mdp"
         endif
         inquire ( file = filename , exist = exi )
         if (.not. exi ) then
            open(newunit=lunfil,file=fileerr,status='replace')
            write(*,'(3a)',iostat=ioerr) 'ERROR: Input file from commandline argument named "', trim(filename), '" was not found'
            write(lunfil,'(3a)',iostat=ioerr) 'ERROR: Input file from commandline argument named "', trim(filename),
     &            '" was not found'
            close(lunfil)
            call stop_exit(1)
         endif
      end if
      
      call delpar (filename)

      end program