#!/usr/bin/perl -w
# NAME: fg_runways.pl
# AIM: Read the xml threshold files
# 08/04/2013 geoff mclane http://geoffair.net/mperl
# 2016-12-04 - review
use strict;
use warnings;
use File::Basename;  # split path ($name,$dir,$ext) = fileparse($file [, qr/\.[^.]*/] )
use XML::Simple;
use Data::Dumper;
use Cwd;
my $os = $^O;
my $perl_dir = '/home/geoff/bin';
my $PATH_SEP = '/';
my $temp_dir = '/tmp';
if ($os =~ /win/i) {
    $perl_dir = 'C:\GTools\perl';
    $temp_dir = $perl_dir;
    $PATH_SEP = "\\";
}
unshift(@INC, $perl_dir);
require 'lib_utils.pl' or die "Unable to load 'lib_utils.pl' Check paths in \@INC...\n";
# log file stuff
our ($LF);
my $pgmname = $0;
if ($pgmname =~ /(\\|\/)/) {
    my @tmpsp = split(/(\\|\/)/,$pgmname);
    $pgmname = $tmpsp[-1];
}
my $outfile = $temp_dir.$PATH_SEP."temp.$pgmname.txt";
open_log($outfile);

# user variables
my $VERS = "0.0.1 2013-03-17";
my $load_log = 0;
my $in_dir = '';
my $in_file = '';
my $in_icao = '';
my $in_root = '';

my $fg_scenery = 'G:\S';

my $verbosity = 0;
my $out_file = '';

# ### DEBUG ###
my $debug_on = 0;
# my $def_dir = 'C:\FG\fgdata';
my $def_dir = 'D:\Scenery\terrascenery\data';
# my $test_file = 'D:\Scenery\terrascenery\data\Scenery\Airports\7\0\V\70VA.threshold.xml';
my $test_file = 'G:\S\Airports\L\S\T\LSTZ.threshold.xml';
##my $test_file = 'D:\Scenery\terrascenery\data\Scenery\Airports\L\S\T\LSTZ.threshold.xml';
### program variables
my @warnings = ();
my $cwd = cwd();

sub VERB1() { return $verbosity >= 1; }
sub VERB2() { return $verbosity >= 2; }
sub VERB5() { return $verbosity >= 5; }
sub VERB9() { return $verbosity >= 9; }

sub show_warnings($) {
    my ($val) = @_;
    if (@warnings) {
        prt( "\nGot ".scalar @warnings." WARNINGS...\n" );
        foreach my $itm (@warnings) {
           prt("$itm\n");
        }
        prt("\n");
    } else {
        prt( "\nNo warnings issued.\n\n" ) if (VERB9());
    }
}

sub pgm_exit($$) {
    my ($val,$msg) = @_;
    if (length($msg)) {
        $msg .= "\n" if (!($msg =~ /\n$/));
        prt($msg);
    }
    show_warnings($val);
    close_log($outfile,$load_log);
    exit($val);
}


sub prtw($) {
   my ($tx) = shift;
   $tx =~ s/\n$//;
   prt("$tx\n");
   push(@warnings,$tx);
}

my %icao_hash = ();
my %body_hash = ();
my %thresholds = ();
my $show_runways = 1;
sub show_thresholds_hash() {
    my ($key,$ra,$rcnt,$rllh,$msg,$rev);
    foreach $key (keys %thresholds) {
        $ra = $thresholds{$key};
        $rcnt = scalar @{$ra};
        prt("$key has $rcnt runways\n");
        if ($show_runways) {
            my ($min_lat,$min_lon,$max_lat,$max_lon);
            my ($i,$ra2,$lat,$lon,$rwy,$hdg,$ra3);
            $min_lat = 91;
            $max_lat = -91;
            $min_lon = 181;
            $max_lon = -181;
            my %rwyhash = ();
            for ($i = 0; $i < $rcnt; $i++) {
                #  push(@{$ra4}, [$rwy, $lat, $lon, $hdg, $displ_m, $stopw_m] );
                $ra2 = ${$ra}[$i];  #// extract one
                $rwy = ${$ra2}[0];
                $lat = ${$ra2}[1];
                $lon = ${$ra2}[2];
                $hdg = ${$ra2}[3];
                $min_lat = $lat if ($lat < $min_lat);
                $max_lat = $lat if ($lat > $max_lat);
                $min_lon = $lon if ($lon < $min_lon);
                $max_lon = $lon if ($lon > $max_lon);
                $rwyhash{$rwy} = [] if (!defined $rwyhash{$rwy});
                $ra3 = $rwyhash{$rwy};
                #              0    1    2
                push(@{$ra3}, [$lat,$lon,$hdg]);
            }
            prt("Bounding box $min_lat,$min_lon to $max_lat,$max_lon\n");
            $rcnt = scalar keys(%rwyhash);
            prt("With $rcnt runway markings...\n");
            foreach $key (keys %rwyhash) {
                $ra3 = $rwyhash{$key};
                $rcnt = scalar @{$ra3};
                $msg = '';
                for ($i = 0; $i < $rcnt; $i++) {
                    $rllh = ${$ra3}[$i];
                    $lat = ${$rllh}[0];
                    $lon = ${$rllh}[1];
                    $hdg = ${$rllh}[2];
                    $msg .= "$lat,$lon,$hdg ";
                }

                $rwy = $key;
                $rev = '';
                if ($rwy =~ /^(\d+)(\w*)$/) {
                    $rev = ($1 > 18) ? $1 - 18 : $1 + 18;
                    $rev = '0'.$rev if ($rev < 10);
                    if (defined $2) {
                        $rev .= 'L' if ($2 eq 'R');
                        $rev .= 'R' if ($2 eq 'L');
                        $rev .= 'C' if ($2 eq 'C');
                    }
                }

                # only for display
                $rev .= ' ' while (length($rev) < 3);
                $key .= ' ' while (length($key) < 3);
                prt("Ryw $key - $msg - $rcnt cnt... rev. $rev\n");

            }
        }
    }
}

# the 'key' is the ICAO
# the 'ff'  is the path 'ICAO.threshold.xml' file
# For display output only...
# the 'kcnt' just indicate the file number seq - 0,1,2
# the 'ra2cnt' the runway count seq - 0, 1, 2, 
sub load_xml_file($$$$) {
    my ($key,$ff,$kcnt,$ra2cnt) = @_;
    my $xml = new XML::Simple;
    my $data =  $xml->XMLin($ff);
    if (! defined ${$data}{'runway'}) {
        prt("$kcnt: File [$ff] NOT valid 'ICAO.threshold.xml' file!\n");
        return;
    }
    my $ref_array = ${$data}{'runway'}; # an ARRAY of 'thresholds' HASHES
    my $rhcnt = 0;
    my $rt = ref $ref_array;
    prt("$kcnt: File [$ff] as $rt...\n"); # if (VERB9());
    # 'displ-m' => '91',
    # 'lat' => '37.6117064652036',
    # 'hdg-deg' => '297.91',
    # 'stopw-m' => '0',
    # 'rwy' => '28L',
    # 'lon' => '-122.358344777098'
    my ($displ_m,$lat,$hdg,$stopw_m,$rwy,$lon);
    my ($rh,$ra3,$ra3cnt,$rh3);
    my $dm = 'displ-m';
    my $la = 'lat';
    my $hd = 'hdg-deg';
    my $sw = 'stopw-m';
    my $rw = 'rwy';
    my $lo = 'lon';
    $thresholds{$key} = [] if (!defined $thresholds{$key});
    my $ra4 = $thresholds{$key};
    if ($rt eq 'HASH') {
        $rhcnt++;
        if (defined ${$ref_array}{'threshold'}) {
            $ra3 = ${$ref_array}{'threshold'};
            $ra3cnt = 0;
            foreach $rh3 (@{$ra3}) {
                # should be 2 ends
                $ra3cnt++;
                $rwy = ${$rh3}{$rw};
                $lat = ${$rh3}{$la};
                $lon = ${$rh3}{$lo};
                $hdg = ${$rh3}{$hd};
                $displ_m = (defined ${$rh3}{$dm}) ? ${$rh3}{$dm} : 0;
                $stopw_m = (defined ${$rh3}{$sw}) ? ${$rh3}{$sw} : 0;
                if (defined $rwy && defined $lat && defined $lon && defined $hdg) {
                    prt("$kcnt:$ra2cnt:$rhcnt:$ra3cnt: $key $rwy $lat $lon $hdg $displ_m $stopw_m\n") if (VERB5());
                    push(@{$ra4}, [$rwy, $lat, $lon, $hdg, $displ_m, $stopw_m] );
                } else {
                    prt("$kcnt:$ra2cnt:$rhcnt:$ra3cnt: $key FAILED!\n");
                    prt(Dumper($rh3));
                    pgm_exit(1,"FAILED 2 $ff\n");
                }
            }
        } else {
            prt("OOPS! No 'threshold' defined!\n");
            prt(Dumper($rh));
            pgm_exit(1,"FAILED 1 $ff\n");
        }
        return;
    }
    foreach $rh (@{$ref_array}) {
        #prt(Dumper($rh));
        $rhcnt++;
        if (defined ${$rh}{'threshold'}) {
            $ra3 = ${$rh}{'threshold'};
            $ra3cnt = 0;
            foreach $rh3 (@{$ra3}) {
                # should be 2 ends
                $ra3cnt++;
                $rwy = ${$rh3}{$rw};
                $lat = ${$rh3}{$la};
                $lon = ${$rh3}{$lo};
                $hdg = ${$rh3}{$hd};
                $displ_m = (defined ${$rh3}{$dm}) ? ${$rh3}{$dm} : 0;
                $stopw_m = (defined ${$rh3}{$sw}) ? ${$rh3}{$sw} : 0;
                if (defined $rwy && defined $lat && defined $lon && defined $hdg) {
                    prt("$kcnt:$ra2cnt:$rhcnt:$ra3cnt: $key $rwy $lat $lon $hdg $displ_m $stopw_m\n") if (VERB5());
                    push(@{$ra4}, [$rwy, $lat, $lon, $hdg, $displ_m, $stopw_m] );
                } else {
                    prt("$kcnt:$ra2cnt:$rhcnt:$ra3cnt: $key FAILED!\n");
                    prt(Dumper($rh3));
                    pgm_exit(1,"FAILED 2 $ff\n");
                }
            }
        } else {
            prt("OOPS! No 'threshold' defined!\n");
            prt(Dumper($rh));
            pgm_exit(1,"FAILED 1 $ff\n");
        }
    }
    ### prt(Dumper($data)); 
    ### pgm_exit(1,"Found $ff\n");
}


sub show_icao_hash() {
    my @arr = keys %icao_hash;
    my $kcnt = scalar @arr;
    prt("Got $kcnt ICAO entries in hash...\n");
    my @arr2 = keys %body_hash;
    my $bcnt = scalar @arr2;
    prt("with $bcnt xml type files - "); # .join(" ",@arr2)."\n");
    my ($cnt,$body,$ra,$key,$ra2,$ff,$xml,$data,$ref_array,$rh);
    my ($ra3,$rh3,$ra2cnt,$ra3cnt,$rhcnt);
    my ($ra4);
    # 'displ-m' => '91',
    # 'lat' => '37.6117064652036',
    # 'hdg-deg' => '297.91',
    # 'stopw-m' => '0',
    # 'rwy' => '28L',
    # 'lon' => '-122.358344777098'
    my ($displ_m,$lat,$hdg,$stopw_m,$rwy,$lon);
    my $dm = 'displ-m';
    my $la = 'lat';
    my $hd = 'hdg-deg';
    my $sw = 'stopw-m';
    my $rw = 'rwy';
    my $lo = 'lon';
    foreach $body (@arr2) {
        $cnt = $body_hash{$body};
        prt("$body=$cnt ");
    }
    prt("\n");
    $kcnt = 0;
    foreach $key (@arr) {
        $kcnt++;
        ###next if ($key ne 'KSFO');
        ###next if (defined $exceptions{$key});
        $ra = $icao_hash{$key};
        #               0     1
        # push(@{$ra}, [$body,$ff]);
        $ra2cnt = 0;
        foreach $ra2 (@{$ra}) {
            $ra2cnt++;
            $body = ${$ra2}[0];
            $ff   = ${$ra2}[1];
            if ($body eq 'threshold') {
                load_xml_file($key,$ff,$kcnt,$ra2cnt);
            }
        }

    }
}


sub get_icao_xml($);
# EXCEPTION: LKTB-groundnet.xml
sub get_icao_xml($) {
    my $dir = shift;
    if (! opendir(DIR,"$dir")) {
        prtw("WARNING: Unable to open dir $dir!\n");
        return;
    }
    my @files = readdir(DIR);
    closedir(DIR);
    my ($file,$ff,$dcnt,$icao,$body,$ra);
    my @dirs = ();
    my $fcnt = 0;
    ut_fix_directory(\$dir);
    foreach $file (@files) {
        next if ($file eq '.');
        next if ($file eq '..');
        $ff = $dir.$file;
        if (-d $ff) {
            push(@dirs,$ff);
        } elsif (-f $ff) {
            if ($file =~ /^(\w+)\.(.+)\.xml$/) {
                $icao = $1;
                $body = $2;
                $icao_hash{$icao} = [] if (!defined $icao_hash{$icao});
                $ra = $icao_hash{$icao};
                push(@{$ra}, [$body,$ff]);
                if (defined $body_hash{$body}) {
                    $body_hash{$body}++;
                } else {
                    $body_hash{$body} = 1;
                }
            } elsif ($file =~ /^(\w+)-(.+)\.xml$/) {
                $icao = $1;
                $body = $2;
                $icao_hash{$icao} = [] if (!defined $icao_hash{$icao});
                $ra = $icao_hash{$icao};
                push(@{$ra}, [$body,$ff]);
                if (defined $body_hash{$body}) {
                    $body_hash{$body}++;
                } else {
                    $body_hash{$body} = 1;
                }
            } else {
                prtw("WARNING: What is this? [$ff] [$file] FIX ME\n");
            }
            $fcnt++;
        } else {
            prtw("WARNING: Check this item [$ff] [$file]!\n");
        }
    }
    $dcnt = scalar @dirs;
    foreach $dir (@dirs) {
        get_icao_xml($dir);
    }
}


sub get_groundnet_list($) {
    my $dir = shift;
    if (! opendir(DIR,"$dir")) {
        prtw("WARNING: Unable to open dir $dir!\n");
        return;
    }
    my @files = readdir(DIR);
    closedir(DIR);
    my ($file,$ff,$dcnt);
    my @dirs = ();
    my $fcnt = 0;
    ut_fix_directory(\$dir);
    foreach $file (@files) {
        next if ($file eq '.');
        next if ($file eq '..');
        $ff = $dir.$file;
        if (-d $ff) {
            push(@dirs,$ff);
        } elsif (-f $ff) {
            $fcnt++;
        } else {
            prtw("WARNING: Check this item [$ff] [$file]!\n");
        }
    }
    $dcnt = scalar @dirs;
    prt("Found $fcnt files, and $dcnt directories in [$dir]...\n");
    foreach $dir (@dirs) {
        get_icao_xml($dir);
    }
}

sub process_in_dir($) {
    my $dir = shift;
    if (! opendir(DIR,"$dir")) {
        prtw("WARNING: Unable to open dir $dir!\n");
        return;
    }
    my @files = readdir(DIR);
    closedir(DIR);
    my ($file,$ff,$dcnt);
    my @dirs = ();
    my $fcnt = 0;
    my $aidir = '';
    my $apdir = '';
    my $scdir = '';
    ut_fix_directory(\$dir);
    foreach $file (@files) {
        next if ($file eq '.');
        next if ($file eq '..');
        $ff = $dir.$file;
        if (-d $ff) {
            push(@dirs,$ff);
            if ($file eq 'AI') {
                ut_fix_directory(\$ff);
                $ff .= 'airports';
                if (-d $ff) {
                    $aidir = $ff;
                }
            } elsif ($file eq 'Airports') {
                $apdir = $ff;
            } elsif ($file eq 'Scenery') {
                ut_fix_directory(\$ff);
                $ff .= 'Airports';
                if (-d $ff) {
                    $scdir = $ff;
                }
            }
        } elsif (-f $ff) {
            $fcnt++;
        } else {
            prtw("WARNING: Check this item [$ff] [$file]!\n");
        }
    }
    $dcnt = scalar @dirs;
    prt("Found $fcnt files, and $dcnt directories...\n");
    prt("Found 'AI' directory [$aidir]\n") if (length($aidir));
    prt("Found 'Airports' directory [$apdir]\n") if (length($apdir));
    if (length($scdir)) {
        prt("Found 'Scenery/Airports' directory [$scdir]\n");
        get_groundnet_list($scdir);
    }

}

sub load_file($) {
    my $ff = shift;
    if (-f $ff) {
        prt("Loading file '$ff'...\n");
        my ($file,$dir) = fileparse($ff);
        my ($icao,$body,$ra);
        if ($file =~ /^(\w+)\.(.+)\.xml$/) {
            $icao = $1;
            $body = $2;
            $icao_hash{$icao} = [] if (!defined $icao_hash{$icao});
            $ra = $icao_hash{$icao};
            push(@{$ra}, [$body,$ff]);
            if (defined $body_hash{$body}) {
                $body_hash{$body}++;
            } else {
                $body_hash{$body} = 1;
            }
            if ($body ne 'threshold') {
                prtw("WARNING: File name [$file] does not appear to be of form ICAO.threshold.xml!\nbut will attempt a load...\n");
            }
            load_xml_file($icao,$ff,0,0);
        } elsif ($file =~ /^(\w+)-(.+)\.xml$/) {
            $icao = $1;
            $body = $2;
            $icao_hash{$icao} = [] if (!defined $icao_hash{$icao});
            $ra = $icao_hash{$icao};
            push(@{$ra}, [$body,$ff]);
            if (defined $body_hash{$body}) {
                $body_hash{$body}++;
            } else {
                $body_hash{$body} = 1;
            }
            if ($body ne 'threshold') {
                prtw("WARNING: File name [$file] does not appear to be of form ICAO.threshold.xml!\nbut will attempt a load...\n");
            }
            load_xml_file($icao,$ff,0,0);
        } else {
            prtw("WARNING: File name [$file] does not appear to be of form ICAO.threshold.xml!\nbut will attempt a load...\n");
            load_xml_file("UNKNONW",$in_file,0,0);
        }
    }
}

sub find_icao($$) {
    my ($icao,$root) = @_;
    if (! -d $root) {
        pgm_exit(1,"ERROR: Unable to find ROOT directory [$root]! Check name, location...\n");
    }
    my $len = length($icao);
    if ( !(($len == 3) || ($len == 4)) ) {
        pgm_exit(1,"ERROR: Expect a 3 or 4 character ICAO '$icao'! Got $len. Check value...\n");
    }
    my @arr = ();
    my ($i,$ch);
    my $path = $root.$PATH_SEP.'Airports';
    if (! -d $path) {
        pgm_exit(1,"ERROR: Unable to find ROOT directory '$path'! Check name, location...\n");
    }
    for ($i = 0; $i < $len; $i++) {
        $ch = substr($icao,$i,1);
        push(@arr,$ch);
        if ($i < 3) {
            $path .= $PATH_SEP.$ch;
        }
    }
    my $file = $path.$PATH_SEP."$icao.threshold.xml";
    if (-f $file) {
        load_file($file);
    } else {
        prt("Finding '$icao', in '$root', file $file FAILED\n");
    }
}


#########################################
### MAIN ###
parse_args(@ARGV);
if (length($in_icao)) {
    find_icao($in_icao,$in_root);
} elsif (length($in_file)) {
    load_file($in_file);
} elsif (length($in_dir)) {
    process_in_dir($in_dir);
}

###show_icao_hash();
show_thresholds_hash();

pgm_exit(0,"");
########################################

sub need_arg {
    my ($arg,@av) = @_;
    pgm_exit(1,"ERROR: [$arg] must have a following argument!\n") if (!@av);
}

sub parse_args {
    my (@av) = @_;
    my ($arg,$sarg);
    while (@av) {
        $arg = $av[0];
        if ($arg =~ /^-/) {
            $sarg = substr($arg,1);
            $sarg = substr($sarg,1) while ($sarg =~ /^-/);
            if (($sarg =~ /^h/i)||($sarg eq '?')) {
                give_help();
                pgm_exit(0,"Help exit(0)");
            } elsif ($sarg =~ /^v/) {
                if ($sarg =~ /^v.*(\d+)$/) {
                    $verbosity = $1;
                } else {
                    while ($sarg =~ /^v/) {
                        $verbosity++;
                        $sarg = substr($sarg,1);
                    }
                }
                prt("Verbosity = $verbosity\n") if (VERB1());
            } elsif ($sarg =~ /^l/) {
                if ($sarg =~ /^ll/) {
                    $load_log = 2;
                } else {
                    $load_log = 1;
                }
                prt("Set to load log at end. ($load_log)\n") if (VERB1());
            } elsif ($sarg =~ /^o/) {
                need_arg(@av);
                shift @av;
                $sarg = $av[0];
                $out_file = $sarg;
                prt("Set out file to [$out_file].\n") if (VERB1());
            } else {
                pgm_exit(1,"ERROR: Invalid argument [$arg]! Try -?\n");
            }
        } else {
            # what do we have here?
            if (-f $arg) {
                $in_file = $arg;
            } elsif (-d $arg) {
                $in_dir = $arg;
                prt("Set direcotry input to [$in_dir]\n") if (VERB1());
            } elsif ((length($arg) == 4)||(length($arg) == 3)) {
                $in_icao = $arg;
                prt("Set ICAO input to [$in_icao]\n") if (VERB1());
            }
        }
        shift @av;
    }

    if ($debug_on) {
        prtw("WARNING: DEBUG is ON!\n");
        if ((length($in_file) == 0) && length($test_file) && ( -f $test_file )) {
            $in_file = $test_file;
            prt("Set DEFAULT input file to [$in_file]\n");
        #} elsif ((length($in_dir) ==  0) && length($def_dir) && ( -d $def_dir )) {
        #    $in_dir = $def_dir;
        #    prt("Set DEFAULT input directory to [$in_dir]\n");
        }
        $load_log = 2;
    }
    if ((length($in_dir) ==  0)&&(length($in_file) == 0)&&(length($in_icao) == 0)) {
        pgm_exit(1,"ERROR: No inputs found in command!\n");
    }
    if (length($in_file) && (! -f $in_file)) {
        pgm_exit(1,"ERROR: Unable to find file [$in_file]! Check name, location...\n");
    }
    if (length($in_dir) && (! -d $in_dir)) {
        pgm_exit(1,"ERROR: Unable to find in directory [$in_dir]! Check name, location...\n");
    }
    if (length($in_root) && (! -d $in_root)) {
        pgm_exit(1,"ERROR: Unable to find ROOT directory [$in_root]! Check name, location...\n");
    }
    if (length($in_icao)) {
        if (length($in_root) == 0) {
            $in_root = $fg_scenery;
        }
        if (! -d $in_root) {
            pgm_exit(1,"ERROR: Unable use ICAO '$in_icao', without scenery ROOT directory [$in_root]!\n");
        }
    }

}

sub give_help {
    prt("$pgmname: version $VERS\n");
    prt("Usage: $pgmname [options] fg-root-dir or in-file\n");
    prt("Options:\n");
    prt(" --help  (-h or -?) = This help, and exit 0.\n");
    prt(" --verb[n]     (-v) = Bump [or set] verbosity. def=$verbosity\n");
    prt(" --load        (-l) = Load LOG at end. ($outfile)\n");
    prt(" --out <file>  (-o) = Write output to this file.\n");
}

sub info() {
    my $txt = <<EOF;
from : http://wiki.flightgear.org/About_Scenery/Airports

For the transition periode (FlightGear 2.0.0 till 2.4.0), a new property was introduced. 
Users of those versions can choose which set of data to use, by toggleing the property 
/sim/use-custom-scenery-data. 

Whenever this boolean property is set to false, ground network data will be read from 
\$FG_ROOT/AI/Airports/[ICAO] and when set to true, it is read from 
\$FG_SCENERY/Airports/[I]/[C]/[A]/[ICAO].groundnet.xml. 

This property controls the following: 
 Reading of startup information: When set to "true", the runway dimension data in apt.dat 
 are overwritten by those in the \$FG_SCENERY/Airports/[I]/[C]/[A], so that there is more 
 flexibility in regenerating the terrain tiles without having to force the updated runway 
 positions back into apt.dat. 
 Use of ground networks. 
 Runway-use files. 

Re: XML::Simple
from : http://www.techrepublic.com/article/parsing-xml-documents-with-perls-xmlsimple/5363190

There used to be two ways of doing this: 
setting up callback handlers that get invoked when a particular element type is recognized (SAX), or 
creating an XML document tree and using tree navigation methods to access individual content fragments (DOM).

shell> perl -MCPAN -e shell
cpan> install XML::Simple 

File: D:\\Scenery\\terrascenery\\data\\Scenery\\Airports\\7\\0\\V\\70VA.threshold.xml
\$VAR1 = {
          'runway' => {
                      'threshold' => [
                                     {
                                       'displ-m' => '0',
                                       'lat' => '37.0739669185387',
                                       'hdg-deg' => '54.00',
                                       'stopw-m' => '0',
                                       'rwy' => '06',
                                       'lon' => '-79.8297582101689'
                                     },
                                     {
                                       'displ-m' => '0',
                                       'lat' => '37.0768690288565',
                                       'hdg-deg' => '234.00',
                                       'stopw-m' => '0',
                                       'rwy' => '24',
                                       'lon' => '-79.824751694029'
                                     }
                                   ]
                    }
        };

File:  D:\\Scenery\\terrascenery\\data\\Scenery\\Airports\\K\\S\\F\\KSFO.threshold.xml
ie \$ref_array = \${\$data}{'runway'}; # an ARRAY of 'thresholds' HASHES
so foreach \$rh (\@{\$ref_array}) {
then 
\$VAR1 = {
          'runway' => [
                      {
                        'threshold' => [
                                       {
                                         'displ-m' => '150',
                                         'lat' => '37.6089861020029',
                                         'hdg-deg' => '27.70',
                                         'stopw-m' => '0',
                                         'rwy' => '01L',
                                         'lon' => '-122.382198312909'
                                       },
                                       {
                                         'displ-m' => '107',
                                         'lat' => '37.6272055903445',
                                         'hdg-deg' => '207.70',
                                         'stopw-m' => '0',
                                         'rwy' => '19R',
                                         'lon' => '-122.370122207455'
                                       }
                                     ]
                      },
                      {
                        'threshold' => [
                                       {
                                         'displ-m' => '73',
                                         'lat' => '37.6068179874086',
                                         'hdg-deg' => '27.71',
                                         'stopw-m' => '0',
                                         'rwy' => '01R',
                                         'lon' => '-122.380713288884'
                                       },
                                       {
                                         'displ-m' => '0',
                                         'lat' => '37.6278236033164',
                                         'hdg-deg' => '207.71',
                                         'stopw-m' => '0',
                                         'rwy' => '19L',
                                         'lon' => '-122.366784743638'
                                       }
                                     ]
                      },
                      {
                        'threshold' => [
                                       {
                                         'displ-m' => '91',
                                         'lat' => '37.6287336332232',
                                         'hdg-deg' => '117.90',
                                         'stopw-m' => '0',
                                         'rwy' => '10L',
                                         'lon' => '-122.39339042147'
                                       },
                                       {
                                         'displ-m' => '91',
                                         'lat' => '37.6135315946418',
                                         'hdg-deg' => '297.90',
                                         'stopw-m' => '0',
                                         'rwy' => '28R',
                                         'lon' => '-122.357141284717'
                                       }
                                     ]
                      },
                      {
                        'threshold' => [
                                       {
                                         'displ-m' => '91',
                                         'lat' => '37.6252893238143',
                                         'hdg-deg' => '117.91',
                                         'stopw-m' => '0',
                                         'rwy' => '10R',
                                         'lon' => '-122.390718180036'
                                       },
                                       {
                                         'displ-m' => '91',
                                         'lat' => '37.6117064652036',
                                         'hdg-deg' => '297.91',
                                         'stopw-m' => '0',
                                         'rwy' => '28L',
                                         'lon' => '-122.358344777098'
                                       }
                                     ]
                      }
                    ]
        };

EOF
    return $txt;
}

# eof - template.pl