#!/bin/bash
################################################################################
## Copyright (C) 2022 Potsdam Institute for Climate Impact Research (PIK),    ##
## see COPYRIGHT file.                                                        ##
##                                                                            ##
## This file is part of LandInG and licensed under GNU AGPL Version 3 or      ##
## later. See LICENSE file or go to http://www.gnu.org/licenses/              ##
## Contact: https://github.com/PIK-LPJmL/LandInG/                             ##
################################################################################

################################################################################
## This script converts ASCII grids unzipped by step 1 into NetCDF files.     ##
## Requires Climate Data Operators (CDO).                                     ##
## Settings:                                                                  ##
## TYPE: "lu" for land use data; HYDE also contains population density data   ##
##       which can be converted by setting TYPE to "pop"                      ##
## STARTYEAR: first year of data to convert (HYDE data currently cover 10000  ##
##            BC to 2017. Data are centennial until 1700, decadal from 1700-  ##
##            2000 and annual after 2000)                                     ##
## LASTYEAR: last year of data to convert (default: 2017, last year of HYDE)  ##
## ASCIIDIR: directory where ASCII files are located (default: unzipped)      ##
## NCDIR: directory where NetCDF files are created (default: ncdf_tmp)        ##
################################################################################

TYPE="lu"
STARTYEAR=1500
LASTYEAR=2017
ASCIIDIR="unzipped"
NCDIR="ncdf_tmp"

for IDIR in $ASCIIDIR/*_$TYPE;do
  ODIR=$NCDIR/$(echo $IDIR|awk -F"/" '{print $NF}')

  for FILE in $IDIR/*.asc;do
    TIME=$(dirname $FILE |awk -F"/" '{print $NF}'|sed s/_$TYPE//)
    VAR=$(basename $FILE .asc | sed s/$TIME//)
    CAL=$(echo -n $TIME | tail -c2)

    case $CAL in
      AD)
        YEAR=$(echo $TIME|sed s/$CAL//)
        ;;
      BC)
        YEAR=$(echo -$TIME|sed s/$CAL//)
        ;;
    esac

    [[ $YEAR -lt $STARTYEAR || $YEAR -gt $LASTYEAR ]] && continue

    mkdir -p $ODIR
    echo " $FILE $VAR $CAL $YEAR ..."
    ## This keeps trying until files are converted successfully.
    while [ ! -f $ODIR/${VAR}_$YEAR.nc4 ];do
      cdo --history -m -9999 -f nc4c -z zip -s \
          -setreftime,$STARTYEAR-01-01,00:00:00,1years \
          -settaxis,$YEAR-01-01,00:00:00,1years \
          -setname,$VAR -setmissval,1E+20 -invertlatdata -setunit,km^2 \
          -input,grid.txt $ODIR/${VAR}_$YEAR.nc4 < $FILE
    done
  done
done
echo "...done"