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

! $Id: unstruc_files.f90 42642 2015-10-21 11:34:20Z dam_ar $
! $HeadURL: https://repos.deltares.nl/repos/ds/trunk/additional/unstruc/src/unstruc_files.f90 $

module unstruc_files
!! Centralizes unstruc file management (formerly in REST.F90)

use unstruc_messages
use unstruc_version_module

implicit none

    integer, parameter :: ERR_FILENOTEXIST    = 1
    integer, parameter :: ERR_FILEALREADYOPEN = 2
    integer, parameter :: ERR_FILEACCESSDENIED= 3

    integer, parameter :: maxlength = 256  !< Max length of a file name (not checked upon).
    integer            :: maxnum = 0       !< Current length of filenames list.
    character(maxlength), dimension(:), allocatable :: filenames

    integer :: mdia = 0 !< File pointer to .dia file
    integer :: mini = 0 !< File pointer to .ini file
    integer :: mhlp = 0 !< File pointer to help file
    
    character(len=60)  :: pathdi          ! TODO: AvD: TEMP. moved from hwsw.inc
   
contains

subroutine init_unstruc_files()

end subroutine init_unstruc_files


!> Registers in the filenames list that a file is opened.
!! Use this instead of directly writing in the list (automatic realloc).
!! The actual open is not performed here.
subroutine reg_file_open(mfil, filename)
    use m_alloc
    integer,          intent(in) :: mfil     !< File unit number (e.g., from numuni)
    character(len=*), intent(in) :: filename
 
    if (mfil > maxnum) then
        MAXNUM = MFIL + 50
        call realloc(filenames, maxnum, fill=' ')
    end if

    filenames(mfil) = filename
end subroutine


!> 'Unregisters' a file name from the list upon closing.
!! The actual close is not performed here.
subroutine reg_file_close(mfil)
    integer,          intent(in) :: mfil

    filenames(mfil) = ' '
end subroutine


!> Closes all remaining files in the file list.
subroutine close_all_files()
    integer :: mfil

    do mfil = maxnum,1,-1
        if ( mfil.ne.mdia) then ! SPvdP: need to close dia-file last
          close(mfil) ! No need to check file status, just attempt to close.
          if (filenames(mfil) /= ' ') then
             call mess(LEVEL_INFO, 'Closed file : ', filenames(mfil))
          end if
        end if
    end do
    
    if ( allocated(filenames) ) deallocate(filenames)
    maxnum = 0
end subroutine close_all_files

!> Proposes a filename for a certain file type.
!! If a similar file was previously loaded, that same filename is returned.
!! Otherwise, the basename of the model definition is used with an appropriate suffix.
!! Otherwise, a wildcard is returned. TODO [AvD]
!!
!! When an output directory is configured, the filename is also prefixed with that, unless switched off by prefixWithDirectory=.false..
function defaultFilename(filecat, timestamp, prefixWithDirectory, allowWildcard)
    use unstruc_model
    use m_flowtimes
    implicit none
    
    character(len=*), intent(in)  :: filecat             !< File category for which the filename is requested, e.g. 'obs', 'map', 'hyd'.
    logical, optional, intent(in) :: prefixWithDirectory !< Optional, default true. Prefix file name with the configured output directory. Set this to .false. to get purely the filename.
    logical, optional, intent(in) :: allowWildcard       !< Optional, default false. Allow the result to fall back to *.<ext>, in case no model id or other basename could be found. 
    double precision, optional, intent(in) :: timestamp  !< Optional, default disabled. Form a datetime string out of the timestamp (in seconds) and include it in the filename.

    character(len=255) :: activeFile
    character(len=255) :: basename
    character(len=16)  :: suffix
    character(len=255) :: defaultFilename
    character(len=16)  :: dateandtime

    integer :: L
    logical :: prefix_dir

    if (present(prefixWithDirectory)) then
        prefix_dir = prefixWithDirectory
    else
        prefix_dir = .true.
    end if

    
    activeFile = ' '
    basename   = ' '
    suffix     = ' '
    
    defaultFilename = ' '
    
    select case (trim(filecat))
    case ('obs')
        activeFile = md_obsfile
        suffix     = '_obs.xyn'
    case ('bal')
        activeFile = ''
        suffix     = '.bal'
    case ('map')
        activeFile = md_mapfile
        suffix     = '_map.nc'
    case ('fou')
        activeFile = ''
        suffix     = '_fou.nc'
    case ('avgwavquant')                         !! JRE
        activeFile = md_avgwavquantfile
        suffix     = '_wav.nc'
    case ('tec')
        activeFile = ''
        suffix     = '.dat'
    case ('map.plt')
        activeFile = md_mapfile
        suffix     = '_map.plt'
    case ('net.plt')
        activeFile = md_mapfile
        suffix     = '_net.plt'
    case ('net')
        activeFile = md_netfile
        suffix     = '_net.nc'
    case ('waqgeom')
        activeFile = ''
        suffix     = '_waqgeom.nc'
    case ('ldb')
        activeFile = md_ldbfile
        suffix     = '.ldb'
    case ('rstold')
        activeFile = ''
        suffix     = '.rst'
    case ('rst')
        activeFile = md_restartfile
        suffix     = '_rst.nc'
    case ('his')
        activeFile = md_hisfile
        suffix     = '_his.nc'
    case ('inc_s1')
        activeFile =  ''
        suffix     = '_inc_s1.nc'
    case ('bot')
        activeFile = ''
        suffix     = '.xyb'
    case ('_lev.xyz')
        activeFile = ''
        suffix     = '_lev.xyz' ! dus..    
    case ('com')
        activeFile = md_comfile
        suffix     = '_com.nc'

    ! Delwaq files: filecat is identical to file extension
    case ('hyd','vol','are','flo','poi','len','srf','tau','vdf','tem','sal','atr','bnd')
        if (prefix_dir) then
            basename =  'DFM_DELWAQ_'//trim(md_ident)//trim(rundat2)
        end if
        basename = trim(basename)//trim(md_waqfilebase)
        suffix   = '.'//trim(filecat)
    end select

    if (present(timestamp)) then
        dateandtime = '_'
        call maketime(dateandtime(2:), timestamp)
    else
        dateandtime = ' '
    end if

    ! Now choose the most sensible filename:
    if (len_trim(activeFile) > 0) then                  ! File of this type already active, use that one.
        defaultFileName = activeFile
    elseif (len_trim(basename) > 0) then                ! Create new filename, based on a certain prefix/basename
        defaultFileName = trim(basename)//trim(dateandtime)//suffix
    elseif (len_trim(md_ident) > 0) then                ! No active, no basename, use md_ident as basename
        defaultFilename = trim(md_ident)//trim(dateandtime)//suffix
    elseif (len_trim(md_ident) == 0) then               ! Not even a md_ident, use basename as basename
        defaultFilename = trim(unstruc_basename)//trim(dateandtime)//suffix
    else if(present(allowWildcard)) then                ! Final resort: just a wildcard with proper file extention.
        if (allowWildcard) then
            defaultFilename = '*'//suffix
        end if
    end if

    ! Output files are generally stored in a subfolder, so prefix them here with that.
    select case (trim(filecat))
    case ('his', 'map', 'rstold', 'rst', 'bal', 'inc_s1', 'tec', 'map.plt', 'net.plt', 'avgwavquant', 'com')                             !! JRE
        if (prefix_dir) then
            defaultFilename = trim(getoutputdir())//trim(defaultFilename)
        end if
    end select
    
end function defaultFilename

!> Initializes file pointer to diagnostics file.
!!
!! The filename is determined by the program name and possibly a sequence
!! number. File-open attempts will not continue indefinitely (program may stop).
subroutine inidia(basename)
    use unstruc_model
  
    character(len=*)  :: basename

    integer, external :: numuni
    integer :: ierr
    integer :: jscr
    integer :: k
    integer :: L
    integer :: m
!    integer :: numuni
    CHARACTER(*) FILENAME*256, BASE*256
    character(*) RW*20
   
    if (mdia > 0) return
    
    mdia    = numuni()
   
    L = len_trim(md_ident)
    if (L == 0) then   
       base = trim(basename)
       L    = len_trim(basename)
    else
       base = trim(md_ident)
    end if
    
    filename = trim(base)//'.dia'
    
    K = 0
    ierr = 0
 10 OPEN(mdia, FILE=trim(filename), action='readwrite', IOSTAT=ierr)
    inquire(mdia, readwrite=rw)
    IF (ierr .GT. 0 .or. trim(rw)/='YES') THEN
        K = K + 1
        filename = basename(1:l)//'_000.dia'
        WRITE(filename(L+2:L+4),'(I3.3)') K
        GOTO 10
    ENDIF

    if (k > 0) then
        write (*,*) 'Warning: could not open default diagnostics file.'
        write (*,*) 'Now using '''//trim(filename)//''' instead.'
    end if

    call initMessaging(mdia)

end subroutine inidia



!> Constructs the full path to a file in the system directory.
subroutine sysfilepath(filename, fullpath)
    character(len=*), intent(in)  :: filename
    character(len=*), intent(out) :: fullpath

    fullpath = trim(pathdi)//trim(filename)
end subroutine sysfilepath


SUBROUTINE SYSFIL(LUNID,FILNAM)
    integer :: lunid
    CHARACTER :: FILNAM*76

    integer, external :: numuni

    character :: FULNAM*180
    logical :: ja

    call sysfilepath(filnam, fulnam)
    INQUIRE(FILE= FULNAM,EXIST=JA)
    IF (JA) THEN
        LUNID = NUMUNI()
        OPEN(LUNID,FILE= FULNAM)
        call reg_file_open(lunid, fulnam)
     ENDIF

    RETURN
END SUBROUTINE SYSFIL


!> Constructs the full path to a file in the system directory.
function getfilename(ftype, success)
    character(len=255) :: getfilename
    character(len=*), intent(in) :: ftype
    logical, optional, intent(out) :: success

!    fullpath = trim(pathdi)//trim(filename)
    getfilename='todo' 
    success = .true.
end function getfilename

!> Gets the basename of a file. By default this is the filename without its extension.
!! Optionally, a file category may be specified, such that e.g., '_net.nc'
!! is stripped off (instead of .nc only)
subroutine basename(filename, filebase, filecat)
    implicit none
    character(len=*),           intent(in)  :: filename
    character(len=*),           intent(out) :: filebase
    character(len=*), optional, intent(in)  :: filecat
    
    character(1),     external              :: get_dirsep

    integer :: L1,L2

    ! Strip off file extension
    L2 = len_trim(filename)
    if (present(filecat)) then
        select case (trim(filecat))
        case ('net')
            L2 = L2 - 7 ! '_net.nc'
        case default
            L2 = index(filename, '.', .true.)-1
        end select
    else
        L2 = index(filename, '.', .true.)-1
    end if

    ! Also strip off any preceding dir names.
    L1 = index(filename, get_DIRSEP(), .true.)+1

    filebase = ' '
    filebase = filename(L1:L2)
end subroutine basename


!> get output directory
function getoutputdir()
   use m_flowtimes
   use unstruc_model
   implicit none
   
   character(len=255)         :: getoutputdir
   
   character(len=1), external :: get_dirsep
   
   call datum2(rundat2)
   
   if ( len_trim(md_outputdir)==0 ) then
!     default
      if ( len_trim(md_ident_sequential) > 0 ) then
         getoutputdir = 'DFM_OUTPUT_'//trim(md_ident_sequential)//trim(rundat2)
      else
         getoutputdir = 'DFM_OUTPUT_'//trim(rundat2)
      end if
   else
      getoutputdir = trim(md_outputdir)//get_dirsep()
   end if
   
   return
end function getoutputdir

end module unstruc_files

!>
!> Find out if system is PC (directory seperator character \ (92)
!>   or UNIX (directory seperator character / (47))
function get_dirsep()
   implicit none
   
   character(len=1)     :: get_dirsep
   
   integer :: nval, lslash
   CHARACTER  FILNAM*76
   character  errtxt*8,arch*10,hlpstr*999,slash*1
   
   CALL GET_ENVIRONMENT_VARIABLE('PATH',hlpstr)
   
   slash  = CHAR  (47)
   lslash = INDEX (hlpstr,slash)
   if (lslash .eq. 0) then
      slash  = CHAR  (92)
   endif
   get_dirsep = slash
end function get_dirsep