#!@DASPERL
! +-======-+ 
!  Copyright (c) 2003-2018 United States Government as represented by 
!  the Admistrator of the National Aeronautics and Space Administration.  
!  All Rights Reserved.
!  
!  THIS OPEN  SOURCE  AGREEMENT  ("AGREEMENT") DEFINES  THE  RIGHTS  OF USE,
!  REPRODUCTION,  DISTRIBUTION,  MODIFICATION AND REDISTRIBUTION OF CERTAIN 
!  COMPUTER SOFTWARE ORIGINALLY RELEASED BY THE UNITED STATES GOVERNMENT AS 
!  REPRESENTED BY THE GOVERNMENT AGENCY LISTED BELOW ("GOVERNMENT AGENCY").  
!  THE UNITED STATES GOVERNMENT, AS REPRESENTED BY GOVERNMENT AGENCY, IS AN 
!  INTENDED  THIRD-PARTY  BENEFICIARY  OF  ALL  SUBSEQUENT DISTRIBUTIONS OR 
!  REDISTRIBUTIONS  OF THE  SUBJECT  SOFTWARE.  ANYONE WHO USES, REPRODUCES, 
!  DISTRIBUTES, MODIFIES  OR REDISTRIBUTES THE SUBJECT SOFTWARE, AS DEFINED 
!  HEREIN, OR ANY PART THEREOF,  IS,  BY THAT ACTION, ACCEPTING IN FULL THE 
!  RESPONSIBILITIES AND OBLIGATIONS CONTAINED IN THIS AGREEMENT.
!  
!  Government Agency: National Aeronautics and Space Administration
!  Government Agency Original Software Designation: GSC-15354-1
!  Government Agency Original Software Title:  GEOS-5 GCM Modeling Software
!  User Registration Requested.  Please Visit http://opensource.gsfc.nasa.gov
!  Government Agency Point of Contact for Original Software:  
!  			Dale Hithon, SRA Assistant, (301) 286-2691
!  
! +-======-+ 
# Simple perl script to convert HDF files to GRID. Uses lats4d.
#
# Revision history:
#
# 10feb2000 da Silva  First crack. (in sh script)
# 6/19/2000 Joon Yoon Completely Rewritten in Perl
# 07May2001 da Silva  Clean up.
#

use FindBin;                     # find location of the this script
use lib "$FindBin::Bin";         # make perl libraries available
use Env;                         # make env vars readily available
use File::Basename;              # for basename(), dirname()
use File::Copy;                  # for copy()
use Getopt::Long;                # command line options
use Time::Local;                 # time functions
use Shell qw(cat rcp rsh scp ssh);   # make C-shell commands available

# command line options
# --------------------
  $rc = GetOptions("v", "d", "zrev" ); 
  manpage() if ( $#ARGV < 0 || $ARGV[0] eq 'help' || !$rc ); 

  $myname 	= basename ("$0");

  init();

  foreach $nextarg ( @ARGV ) {
	$doh = `file $nextarg`;
	@doh = split ":", $doh;
	$doh =  @doh[$#doh];
	if ($doh =~ /data/) {
		print "Looks like an HDF data file...\n";
		coards2grib($nextarg);
	} else {
		print "Looks like an ascii text file...\n";
		ieee2grib($nextarg); 
	}
}
exit 0;

# -----------------------------------------------------------------------

sub init { 

  $fvroot  = dirname($FindBin::Bin);

  $ncdump 	= "ncdump";
  $grads  	= "gradshdf";
  $lats4d 	= "$fvroot/lib/grads/lats4d.gs";
  $log    	= "$myname" . ".$$" . ".log";
  $args   	= $#ARGV + 1 ;
  $hybrid 	= "";

  die ">>> ERROR <<< cannot find $lats4d" unless ( -e $lats4d );

  $increment = 0;
  $time_steps = 0;

}

#..........................................................................

sub ieee2grib {

# For each file on input
# ----------------------
	my ($temp)   	= @_;
	$basen 		= basename ("$temp");
	$ctl 		= $basen; 
	open (NONHDF, "$temp") || die (" can't open $temp file ");
		$first_line = <NONHDF>;
	close (NONHDF);
	$bin 		= ((split " ",$first_line)[1]);
	if ( $ctl =~ m/\.ctl/ ) { 
		print "ctl is already attached at end \n";
	} else { 
		print "ctl has been attached at end \n";
		$ctl	.= ".ctl"; 
	}
	$basen          =~ s/\.ctl//g;
	$tempctl 	= $basen . ".ctl_temp";
	$cdl   		= $basen . ".cdl";

	$temp_num = $level_start = $level_ttl = $temp_count = 0;
	$firsttime 	= 1;

#   Do the actual grib conversion
#   -----------------------------
        if ( $opt_d ) {
	  print "bin 	= $bin    \n";
	  print "basen    = $basen  \n";
	  print "ctl      = $ctl    \n";
	  print "log      = $log    \n";
	  print "HYBRID   = $HYBRID \n";
        }

	$cmd = "$grads -blc \'run $lats4d -q -v -i $ctl -o $basen -format ieee\'";
	$rc = System ($cmd, $log);
        die ">>> ERROR <<< running GrADS" if ( $rc );

	open (LOG, "$log") || die ("Couldn't open $log file");
		@log_file = <LOG>;
	close (LOG);	
        $SUCCESSFUL = 0;
	foreach $temp3 (@log_file) {
		if ($temp3 =~ /SUCCESS/ ) { $SUCCESSFUL = 1 }; 
	}
        die ">>> ERROR <<< gribbing $hdf" if ( $SUCCESSFUL );


	$levelfile = $ctl;
	open  (LEVELFILE, "$levelfile") || die ("Can't open $levelfile file");
		@level_file = <LEVELFILE>;
	close (LEVELFILE);
	foreach $temp_z (@level_file) {
		if (($temp_z =~ /levels =/) && $firsttime ) {
			$level_ttl = $temp_num;
			$firsttime=0;
		} elsif ($temp_z =~ /levels =/) {
			$level_start = $temp_num;
		}
		$temp_num++;
	}
	$levels = ();
	foreach $temp_z (@level_file){
		if ($temp_count > $level_start) {
			$temp_z =~ s/\n//sg;
			$temp_z =~ s/\r//sg;
			$temp_z =~ s/^\n//sg;
			$levels = $levels . $temp_z;
		}
		$temp_count++;
	}
	$levels =~ s/}//sg;
	$levels =~ s/,//sg;
	$levels =~ s/;//sg;
	@levels_a = split (" ", $levels);
	$levels_r = "";
	foreach $temp_z (@levels_a) {
		$levels_r = "$temp_z " . $levels_r;
	}
	$stat = rename $ctl,$tempctl; 
	if ($stat == 0 ) {
		print "Error while renameing $ctl to $tempctl";
		exit 2;
	}
	open (TEMPCTL, "$tempctl") || die("Can't open $tempctl file");
	open (CTL, ">$ctl") || die ("Can't open $ctl file");
		while (<TEMPCTL>) {
			$temp_buff = $_;
			if ($temp_buff =~ /levels/ ) {
				print CTL "$temp_buff";
				print CTL "$levels_r\n";
			} elsif ($temp_buff !~ /^\d/) {
				print CTL "$temp_buff";
			}
		}
	close (CTL);
	close (TEMPCTL);

        print "$myname: completed successfully\n" if ( $opt_v);

#       Cleanup mess
#       ------------
        unlink($tempctl);
        unlink($log);
        unlink(".grads.lats.table");

}

#..........................................................................

sub coards2grib {

	my ($hdf) = @_;
        my $basen = basename ("$hdf");
	$basen =~ s/\.nc4//g;
	my $hdf   = $basen . ".nc4";
        my $cdl   = $basen . ".cdl";
        my $ctl   = $basen . ".ctl";
        my $tempctl = $basen . ".ctl_temp";
        
#   Create CDL
#   ----------
        # -c includes coordinate variables as well
        $rc = system ("$ncdump -c $hdf > $cdl");
        die ">>> ERRORR <<< running $ncdump" if ( $rc ); 

#   Do the actual grib conversion
#   -----------------------------
	if ( $opt_d ) {
             print "grads   = $grads  \n";
             print "hdf     = $hdf    \n";
             print "basen   = $basen  \n";
             print "ctl     = $ctl    \n";
             print "tempctl = $tempctl    \n";
             print "log     = $log    \n";
        }
        $cmd = "$grads -blc \'run $lats4d -q -v -i $hdf -o $basen -format grads_grib\' ";
        $rc = System ("$cmd", "$log");
        die ">>> ERROR <<< running $cmd" if ( $rc );

        cat("$log" ) if ( $opt_v );

#       Check grads error code
#       ----------------------
        open (LOG, "$log") || die ("Couldn't open $log file");
                        @log_file = <LOG>;
        close (LOG);    
        $SUCCESSFUL = 0;
        foreach $temp3 (@log_file) {
                #print "$temp3 \n";
                if ($temp3 =~ /SUCCESS/ ) { $SUCCESSFUL = 1 };  
        }
        die ">>> ERROR <<< gribbing $hdf" unless ($SUCCESSFUL );
        

#       Fix levels
#       ----------
        open(CDL, "$cdl") || die ("Can't open $cdl file");
                @cdl_file = <CDL>;
        close(CDL);
        $temp_num =0;
        $level_start = 0;
        $level_ttl = 0;
        $firsttime = 1;
        foreach $temp (@cdl_file) {
                if ( $firsttime ) {
                       if ( ($temp =~ /lev =/) || ($temp =~ /levels =/) ) {
			@temp_num = split (" ", $temp);
			$level_ttl = @temp_num[2];
                        $firsttime=0;
		       }
                } elsif (($temp =~ /lev =/) || ($temp =~ /levels =/ )) {
                        $level_start = $temp_num;
                }
                $temp_num++;
        }
        $temp_count=0;
	$temp_count_mid = 0;
        $levels = ();
        foreach $temp_line (@cdl_file){
                if ($temp_count >= $level_start) {
			@templine = split (" ", $temp_line);
			foreach $temp (@templine){
				$temp =~ s/,//sg;
				if ($temp_count_mid < $level_ttl ) {
					if ($temp =~ /(\d+)/ ){
						$temp_count_mid++;

						$temp =~ s/\n//sg;
						$temp =~ s/\r//sg;
						$temp =~ s/^\n//sg;
						$levels .= " $temp ";
					}
				}
			}
                }
                $temp_count++;
        }
        $levels =~ s/}//sg;
        $levels =~ s/,//sg;
        $levels =~ s/;//sg;
        @levels_a = split (" ", $levels);
        $levels_r = "";
        foreach $temp (@levels_a) {
            if ( $opt_zrev ) {
                 $levels_r = "$temp " . $levels_r;
	       } else {
                 $levels_r = $levels_r . " $temp" 
               }
        }
        $stat = rename $ctl,$tempctl; 
        if ($stat == 0 ) {
                die "Error while renaming $ctl to $tempctl";
        }
        open (TEMPCTL, "$tempctl") || die("Can't open $tempctl file");
        open (CTL, ">$ctl") || die ("Can't open $ctl file");
                while (<TEMPCTL>) {
                        $temp_buff = $_;
                        if ( ($temp_buff =~ /levels/ ) || ($temp_buff =~ /lev/)) {
                                print CTL "$temp_buff";
                                print CTL "$levels_r\n";
                        } elsif ($temp_buff !~ /^\d/) {
                                print CTL "$temp_buff";
                        }
                }
        close (CTL);
        close (TEMPCTL);
        print "$myname: completed successfully\n" if ( $opt_v);

#       Cleanup mess
#       ------------
        unlink($tempctl);
        unlink($log);
        unlink(".grads.lats.table");

}


#......................................................................

#
# System: This routine saves stdout/stderr, redirects it to a specified file, 
#         runs a shell command using this new stdout/stderr, and finally 
#         restores the original stdout/stderr.
#

sub System {

    my ( $cmd, $logfile ) = @_;

    print "$myname: $cmd\n" if ( $opt_v );

    open SAVEOUT, ">&STDOUT";  # save stdout
    open SAVEERR, ">&STDERR";  # save stderr

    open STDOUT, ">>$logfile" or die "can't redirect stdout";
    open STDERR, ">>$logfile" or die "can't redirect stderr";

    select STDERR; $| = 1;     # make it unbuffered
    select STDOUT; $| = 1;     # make it unbuffered

    $rc = system ( $cmd );     # run the shell command

    close STDOUT;
    close STDERR;

    open STDOUT, ">&SAVEOUT" ;  # restore stdout
    open STDERR, ">&SAVEERR" ;  # restore stdout

    return $rc;

  }



#--------------
sub manpage {	
	
print <<EOF1;

NAME
	grads2grib - converts COARDS HDF/NetCDF files to GRIB

SYNOPSIS
	grads2grib [-v] [-d] [-clean] hdf_file(s)

OPTIONS
 -clean remove input file if GRIB conversion sucessfull
 -d     debug mode
 -v     verbose mode
 -zrev  reverse z coordinates

DESCRIPTION
	Given one or more COARDS compliant HDF/NetCDF files,
	this script uses GrADS adnt he lats4d.gs scrip to convert
	the input files to GRIB. In addition to the GRIB
	data file, GrADS control (ctl) and GRIB map (gmp)
	files are also produced, that is, the output files
	are GrADS readable. Since some of the original metadata
	on the original HDF/NetCDF files are not preserved on
	the GRIB output, an ASCII CDL ("Control Data Language")
	file containing all the relevant metadata is also
	generated.

EXAMPLE
	The command

	% grads2grib myfile.nc4
	
	produces the following files:

	myfile.ctl	GrADS control file
	myfile.gmp	GrADS GRIB map
	myfile.grb	actual GRIB data
	myufile.cdl 	ASCII output of "ncdump -c myfile.nc4";
			it shows all relevant metadata in the 
			original file.
	
AUTHOR
	Arlindo da Silva, NASA/GSFC/DAO, dasilva\@gsfc.nasa.gov

	Joon Yoon, jyoon\@dao 		Port to PERL / Minor updates

SEE ALSO
	http://dao.gsfc.nasa.gov/software/grads/lats4d

EOF1
exit 1;
}