#!/bin/ksh
set verbose echo
#
# This script will interpolate horizontaly ERA-I
# output to the desired model grid 
#
# Contact Josefine Ghattas
###############################################################################
###############################################################################
###############################################################################
# BEGIN USER DEFINITION
###############################################################################

# gridfile : file grilles_gcm.nc containing longitudes and latitudes of the destination grid
gridfile=/work/cont003/p86ghatt/GUIDAGE/INTERP_FROM_TS/LMD96x95_grilles_gcm.nc

# indir : path for directory containing the files to interpolate
#indir=/u/rech/psl/rpsl376/ERAI/NETCDF/GLOBAL_075/4xdaily/AN_PL
indir=/dmnfs/cont003/p24data/ERAI/NETCDF/GLOBAL_075/4xdaily/AN_PL
# insuffix : suffix in input files
insuffix=.aphei.GLOBAL_075.nc

# varlist : list of variables to interpolate
varlist="u v ta r"

# Variables for output :
# outdir : directory to store output files
outdir=/dmnfs/cont003/p86ghatt/IGCM_OUT/LMDZOR/NUDGEFILES/LMD9695/ERAI
# outsuffix : suffix to output files
outsuffix=_erai.nc

# Time variables :
# first_year : first year to interpolate
first_year=2000
# last_year : last year to interpolate
last_year=2000

# rundir : temporary run directory
rundir=$CSCRATCHDIR/RUNDIR/interprun
###############################################################################
# END USER DEFINITION
###############################################################################
###############################################################################
###############################################################################
if [ ! -d ${rundir} ] ; then
    mkdir -p ${rundir}
fi
cp -f era2gcm.ksh $rundir/.
cd $rundir

###############################################################################
# For all variables do :
#   1) Interpolate all month and years for each variable
#   2) Add a time step last in each file coming from next month 
###############################################################################
# Loop over all variables
for var in $varlist ; do
    year=$first_year
    month=01

    # 1 - Loop over all files and interpolate the variable
    while [[ ${year} -le ${last_year} ]] ; do
        # Create output directory if it does not exist
	if [ ! -d $outdir/${year} ] ; then
	    mkdir -p $outdir/${year}
	fi

	# Define source and target file
	filein=${indir}/${year}/${var}.${year}${month}${insuffix}
	fileout=${outdir}/${year}/${var}_${year}${month}${outsuffix}

	# Interpolate filein and save in fileout
	echo Interpolate file $filein and save in file $fileout
	./era2gcm.ksh $gridfile $filein tmp.nc $var
	mv tmp.nc $fileout
	echo


	# Find next month and year
	case $month in
	    12)
		nextyear=`expr $year + 1`
		nextmonth=01
		;;
	    *)
		nextyear=$year
		nextmonth=`expr $month + 1`
		if [[ $nextmonth -le 9 ]] ; then
		    nextmonth=0$nextmonth
		fi
		;;
	esac
	# Update month and year
	year=$nextyear
	month=$nextmonth
    done


    # 2 - Loop over all files and add a time step : 
    #     take the first time step from next coming month and add last in current month
    echo Before add step

    year=$first_year
    month=01
    while [[ ${year} -le ${last_year} ]] ; do
	# Find next month and year
	case $month in
	    12)
		nextyear=`expr $year + 1`
		nextmonth=01
		;;
	    *)
		nextyear=$year
		nextmonth=`expr $month + 1`
		if [[ $nextmonth -le 9 ]] ; then
		    nextmonth=0$nextmonth
		fi
		;;
	esac
	
	file=${outdir}/${year}/${var}_${year}${month}${outsuffix}
	nextfile=${outdir}/${year}/${var}_${nextyear}${nextmonth}${outsuffix}
	if [ -f ${nextfile} ] ; then
	    echo First time step from file ${nextfile} will be added last in file ${file}
	    cp -f $file file.nc
	    cp -f $nextfile next.nc
	    ncks -O -d TIME,0,0 next.nc tmp.nc
	    ncrcat -O file.nc tmp.nc tmptot.nc
	    mv tmptot.nc $file
	else
	    echo Next file ${nextfile} does not exist. Nothing will be done for ${file}
	fi

	# Update month and year
	year=$nextyear
	month=$nextmonth
    done


    
# End of loop variable list
done

### Copy gridfile in output dir
cp -f $gridfile $outdir/grilles_gcm.nc
    
exit