#!/usr/bin/env bash
#
# interp, scrip_use and scrip_use_extrap have been written by Virginie Guemas
# in 2011 based on SCRIP software that computes interpolation weights:
# Spherical Coordinate Remapping and Interpolation Package
#
#~~~~~~~~~~~~~~~
# get arguments
#~~~~~~~~~~~~~~~

if [ $# == 0 ]; then
  echo
  echo "USAGE: $(basename $0) <input_file> <input_var> <method> <gridin> <gridout> <output_file> <debug>"
  echo "<method> can be bilinear/bicubic/conserv/distwgt"
  echo "<gridin> and <gridout> can be ORCA1t_v2.2/ORCA1t_v3.2/ORCA025t_v3.2/ERA40/ERAint/EcEarth2/EcEarth3/HadISST/NCEP/NOAAv3b/NSIDC"
  echo "<debug> optional argument in case default choices not convenient : TRUE/FALSE"
  exit 1
fi
 
filein=$1
varin=$2
method=$3
gridin=$4
gridout=$5
fileout=$6
if [ $# == 7 ]; then
  debug=$7
else
  debug='FALSE'
fi

exec='scrip_use'

#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# /cfu/data conventions or not ?
#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

case $gridin in
  'ORCA1t_v2.2'|'ORCA1t_v3.2'|'ORCA025t_v3.2'|'NSIDC') 
   flag1='FALSE'
   ;;
  'NCEP'|'ERAint'|'ERA40'|'EcEarth2'|'EcEarth3'|'HadISST'|'NOAAv3b') 
   flag1='TRUE'
   ;;
  *) 
   flag1='FALSE'
   ;;
esac

case $gridin in 
  'ERA40'|'ERAint'|'EcEarth2'|'EcEarth3'|'HadISST'|'NCEP'|'NOAAv3b'|'NSIDC') 
   flag2='TRUE'
   ;;
  'ORCA1t_v2.2'|'ORCA1t_v3.2'|'ORCA025t_v3.2') 
   flag2='FALSE'
   ;;
  *)
   flag2='FALSE' 
   ;;
esac

#~~~~~~~~~~~~~~~~~~~~
# land data or not ?
#~~~~~~~~~~~~~~~~~~~~

case $varin in
  'tas'|'prlr'|'g500'|'g200'|'psl'|'hflsd'|'hfssd'|'hus'|'rls'|'rss'|'rsds'|'vas'|'uas'|'tasmax'|'tasmin') ;;
  'tos'|'ice'|'mld'|'sic'|'sit'|'sea_ice_area_fraction') gridin=${gridin}'_ocean' ;;
  'ice_pres'|'somixhgt'|'sosstsst'|'sosaline'|'iicethic'|'ileadfra'|'isnowthi'|'iicetemp'|'somxl010'|'somxlheatc'|'somxlsaltc'|'sobarstfu'|'sobarstfv'|'sobarstf'|'heatc_sl'|'vertmeansal'|'votemper'|'vosaline'|'rhopn') gridout=${gridout}'_ocean' ;;
  *) echo "unexpected input variable : contact Virginie" ; exit 1 ;;
esac

#~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# Weigths available or not ?
#~~~~~~~~~~~~~~~~~~~~~~~~~~~~

if [[ ! -e /cfu/pub/scripts/interpolation/weigths/rmp_${gridin}_to_${gridout}_${method}.nc ]] ; then
  echo "unexpected input or output grid : contact Virginie" 
  exit 1
fi

#~~~~~~~~~~~~~~~
# Interpolation
#~~~~~~~~~~~~~~~

if [[ ! -e ${filein} ]] ; then
  echo ${filein}" does not exist" 
  exit 1
fi

vars=`cdo showvar ${filein}`
exist='FALSE'
for var in $vars ; do 
  if [[ $var == ${varin} ]] ; then exist='TRUE' ; fi
done
if [[ $exist == 'FALSE' ]] ; then
  echo $var" is not in input file" 
  exit 1
fi

cat > scrip_use_in <<EOF
&remap_inputs
    remap_wgt   = '/cfu/pub/scripts/interpolation/weigths/rmp_${gridin}_to_${gridout}_${method}.nc'
    infile      = '${filein}'
    invertlat   = ${flag1}
    var         = '${varin}'
    fromregular = ${flag2}
    outfile     = '${fileout}'
/
EOF

ln -sf /cfu/pub/scripts/interpolation/${exec} ${exec}
./${exec}

if [[ $debug == 'FALSE' ]] ; then
  rm -f ${exec} scrip_use_in
else
  ln -sf /cfu/pub/scripts/interpolation/${exec}_extrap ${exec}_extrap
fi