# on Windows: perl .\geo_stream.pl [--static|s OR --live|l] <log_file_name>
# on linux: carmel exec perl ./geo_stream.pl [--static|s OR --live|l] <log_file_name>
# options for static:
#   --deduct-time|-d <seconds>     time in seconds to fast-forward log timestamps
#   --test|-t                      output all lines of log.txt (for testing)
#   --sql_trace|-q                 output SQL queries (not currently using MySQL db)
# options for live:
#   --interval|-i <seconds>        time gap between monitoring log file for size change (default: 0.5)	

=begin
monitor memory useage in powershell:
# Get the Perl process ID
$proc = Get-Process perl

# Monitor it
while ($true) {
    $proc.Refresh()
    "{0:HH:mm:ss} | {1} MB" -f (Get-Date), ([math]::Round($proc.WorkingSet64 / 1MB, 2))
    Start-Sleep 2
}
=cut

use 5.34.0;
use lib '.';
use GeoStream;
use Getopt::Long;
use Time::HiRes qw(sleep);
use autodie qw(open close seek);

use utf8;
use open ':std', ':utf8';
binmode STDOUT, ':encoding(UTF-8)';
binmode STDERR, ':encoding(UTF-8)';
STDOUT->autoflush(1);
STDERR->autoflush(1);

# Handle interrupt gracefully
$SIG{INT} = sub { 
    say STDERR "\nShutting down...";
    exit 0;
};

# Command line options
my %opts;
GetOptions(
 	# static file opts:
	'static|s=s'       => \$opts{static},
	'test|t'           => \$opts{test},
	'sql_trace|q'      => \$opts{sql_trace},
	'deduct-time|d=i'  => \$opts{deduct_time},
	# live stream opts:
	'live|l=s'	       => \$opts{live},
    'interval|i=f'     => \$opts{interval},
);

if (my $file = $opts{static}) {
	read_log($file);
}
elsif ($file = $opts{live}) {
	monitor_log($file);
}
else {
#	pod2usage("Error: Must specify either --static or --live mode\n");
	say 'Error: must specify either --static|s or --live|l mode + filename';
}

sub read_log {
	my $file = shift;
	my $geo = GeoStream->new(
		deduct_time => $opts{deduct_time},
		test_output => $opts{test},
		sql_trace   => $opts{sql_trace},
	);

	open my $fh, '<', $file or die "Can't open $file: $!"; # warn $file;
	while (<$fh>) { # say $_;
		$geo->decode_line($_);
	}
	exit 0;
}

sub monitor_log {
	my $log_file = shift;
	my $interval = $opts{interval} // 0.5;

    my $last_size = -s $log_file // die "Cannot access $log_file: $!\n"; # say $last_size;

	my $geo = GeoStream->new();

=begin # maybe unnecessary?
    # if script opened after x-plane started, will die unless simulation start time set:
    unless ( $geo->sim_start_time ) {
        open my $fh, '<', $log_file;
        while (<$fh>) { # say $_;
            next unless  $_ =~ m/X-Plane Started on (.*)/i;
            $geo->set_sim_start_time($_);
        }
        close $fh;
    }
=cut

    while (1) {
        eval {
            my $size = -s $log_file; # say $size;
            if ($size > $last_size) { # warn 'here';
                open my $fh, '<', $log_file;
                seek($fh, $last_size, 0);
                while (my $line = <$fh>) {
                    $geo->decode_line($line);
                }
                close $fh;
                $last_size = $size;
            }
        };
        warn "Error reading $log_file: $@" if $@;
        sleep $interval;
    }
}

__END__

=head1 NAME

geo_stream_live.pl - Monitor X-Plane log file for geographic data

=head1 SYNOPSIS

    geo_stream_live.pl -f <logfile> [-i <interval>]

    Options:
        -f, --file      Log file to monitor (required)
        -i, --interval  Check interval in seconds (default: 0.5)
        -h, --help      Show this help

=head1 DESCRIPTION

Monitors an X-Plane log file in real-time and processes geographic data.
Handles Windows file streaming limitations.

=cut