#!/bin/ksh
#
# add perturbations to unperturbed wind stress
#
# Set error trapping on
#
set -euvx
#
# Document command line options
#
usage="Usage:\n$0 -o <output directory> -e expid -b bastime -N npert_tot -i input_dir_for_pert -D mesh_dir"
#
# Set defaults for command line options
#
expid=unknown
basetime=unknown
outdir=unknown
prtdir=unknown
inpdir=unknown
fctot=unknown
errflg=0
#
# Get command line options
# 
while getopts b:N:o:e:i:D: option
do
  case $option in
    e) expid=$OPTARG;;
    b) basetime=$OPTARG;;
    N) fctot=$OPTARG;;
    o) outdir=$OPTARG;;
    i) prtdir=$OPTARG;;
    D) inpdir=$OPTARG;;
    \?) errflg=1;;
  esac
done
#
# Check for errors
#
if [[ $errflg -ne 0 || $outdir = unknown || $expid = unknown || $fctot = unknown || $basetime = unknown || $prtdir = unknown || $inpdir = unknown ]] ; then
  print $usage
  exit 1
fi
#
# Check that directories exists.
#
CHECK_DIR $outdir

year=$(substring $basetime 1 4)
mon=$(substring $basetime 5 6)
ln -sf $inpdir/mesh_mask.nc . 
ln -sf $inpdir/bathy_meter.nc .

fcpert=1
while (( $fcpert < $fctot )) ;do

fxout=$outdir/p${fcpert}_utau_y${year}m${mon}.nc
fyout=$outdir/p${fcpert}_vtau_y${year}m${mon}.nc

if [[ ! -s $fxout || ! -s $fyout ]] ;then 
cat >wstr_choice.in<<EOF
&wstr_choice
   expver='$expid'
   fctot=$fctot
   fcpert=$fcpert
   basetime=$basetime
   diffileu='$prtdir/difYYYY_grid_U.nc'
   diffilev='$prtdir/difYYYY_grid_V.nc'
   outfileu='wstrpert_grid_U.nc'
   outfilev='wstrpert_grid_V.nc'
 /
EOF

$BINS/pert_wstr_orca < wstr_choice.in
mv wstrpert_grid_U.nc $fxout
mv wstrpert_grid_V.nc $fyout

fi
(( fcpert = fcpert + 1 ))
done