#!/usr/bin/perl

#-----------------------------------------------------------------
# USAGE:  getgrid.pl in=file.info out=file.elev
#
#	in - dem2ppm info file.
#	out - parse info file to get geospatial grid infomation and output.
#
#-----------------------------------------------------------------
for ($i=0; $i<=$#ARGV; $i++) {
	$pair = $ARGV[$i];      # Get this parameter/value pair
	($param, $value) = split("=", $pair);   # Split pair at =

	if( $param =~ /\bin\b/) {
		$infofile = $value;
		if( -e $infofile) {
			print "dem2ppm info file: $infofile \n";
		} else {
			print STDERR "Input file does not exist!\n";
			exit(0);
		}
	} elsif( $param =~ /\bout\b/) {
		$elevfile = $value;
	} else {
		print STDERR "ERROR: Specified Illegal command-line option!\n";
		exit( 0);
	} 
}

open( INFILE, "$infofile");

while( $this_line = <INFILE>) {
	if( $this_line =~ /\bElevation Units=(\d).*/ ) {
		$elevunits = $1;
		if( $elevunits==1) { 
			$elevconv = 0.305; 
		} else {
			$elevconv = 1.0;
		}
	} elsif( $this_line =~ /Coordinates:.*/ ) {
		for( $icoord=0; $icoord<4; $icoord++) {
			$this_line = <INFILE>;
			if( $this_line =~ /\D+(\d+\.\d+),(\d+\.\d+).*/ ) {
				$xcoord[$icoord] = $1;  $ycoord[$icoord] = $2;
			}
		}
	} elsif( $this_line =~ /Min\/Max Elevation:\D+(\d+\.\d+)\/(\d+\.\d+).*/ ) {
		$minelev = $1;  $maxelev = $2;
	}
}

$minelev = $minelev*$elevconv;  $maxelev = $maxelev*$elevconv;

close( INFILE);
open( OUTFILE, "> $elevfile");

print OUTFILE "@xcoord\n";
print OUTFILE "@ycoord\n";
print OUTFILE "$minelev $maxelev";
close( OUTFILE);

exit(0);