#!/usr/bin/perl
#
# Open an SSH tunnel using the Net::OpenSSH module and keep it opened with an infinite loop.
#
# Note: this is a temporary solution to avoid directly calling the SSH command.
#

use strict;
use warnings;
use Anvil::Tools;
use Net::OpenSSH;

$| = 1;

my $THIS_FILE           =  ($0 =~ /^.*\/(.*)$/)[0];
my $running_directory   =  ($0 =~ /^(.*?)\/$THIS_FILE$/)[0];
if (($running_directory =~ /^\./) && ($ENV{PWD}))
{
	$running_directory =~ s/^\./$ENV{PWD}/;
}

my $anvil = Anvil::Tools->new();
my $ssh_fh;

sub open_ssh_tunnel
{
	my $parameters          = shift;

	# Required parameters:
	my $remote_user         = $parameters->{remote_user};
	my $target              = $parameters->{target};
	my $forward_local_port  = $parameters->{forward_local_port};
	my $forward_remote_port = $parameters->{forward_remote_port};

	if ((not defined $remote_user)
		or (not defined $target)
		or (not defined $forward_local_port)
		or (not defined $forward_remote_port))
	{
		return 1;
	}

	# Optional parameters:
	my $port                = $parameters->{port} ? $parameters->{port} : 22;

	my $ssh_fh_key          = $remote_user."\@".$target.":".$port;
	my $query               = "
SELECT anv.anvil_password
FROM hosts AS hos
JOIN anvils AS anv
ON hos.host_uuid = anv.anvil_node1_host_uuid
OR hos.host_uuid = anv.anvil_node2_host_uuid
WHERE hos.host_name = ".$anvil->Database->quote($target)."
;";

	my $password = $anvil->Database->query({ query => $query, source => $THIS_FILE, line => __LINE__ })->[0]->[0];

	my ($output, $error, $return_code) = $anvil->Remote->call({
		remote_user => $remote_user,
		target      => $target,
		password    => $password,
		shell_call  => $anvil->data->{path}{exe}{echo}." 1",
		no_cache    => 1,
	});
	$anvil->Log->variables({ source => $THIS_FILE, line => __LINE__, level => 2, list => {
		output      => $output,
		error       => $error,
		return_code => $return_code
	} });

	if ($output eq "1")
	{
		$ssh_fh = $anvil->data->{cache}{ssh_fh}{$ssh_fh_key};

		delete $anvil->data->{cache}{ssh_fh}{$ssh_fh_key};

		$anvil->Log->variables({ source => $THIS_FILE, line => __LINE__, level => 2, list => {
			is_ssh_fh_defined => defined $ssh_fh ? 1 : 0
		} });
	}

	$ssh_fh->system({ ssh_opts => [ "-O", "forward",
		"-L0.0.0.0:".$forward_local_port.":0.0.0.0:".$forward_remote_port ] });

	return 0;
}

sub close_ssh_tunnel
{
	if (defined $ssh_fh->disconnect)
	{
		$ssh_fh->disconnect();

		$anvil->Log->variables({ source => $THIS_FILE, line => __LINE__, level => 2, list => {
			message => "SSH tunnel disconnected."
		} });
	}

	$anvil->nice_exit({ exit_code => 0 });
}

$SIG->{INT}  = \&close_ssh_tunnel;
$SIG->{TERM} = \&close_ssh_tunnel;

$anvil->Get->switches;

$anvil->Database->connect;
$anvil->Log->entry({ source => $THIS_FILE, line => __LINE__, level => 2, secure => 0, key => "log_0132" });
if (not $anvil->data->{sys}{database}{connections})
{
	# No databases, exit.
	$anvil->Log->entry({ source => $THIS_FILE, line => __LINE__, level => 0, 'print' => 1, priority => "err", key => "error_0003" });
	$anvil->nice_exit({ exit_code => 1 });
}

if (open_ssh_tunnel({
	remote_user         => $anvil->data->{switches}{'remote-user'},
	target              => $anvil->data->{switches}{'target'},
	port                => $anvil->data->{switches}{'port'},
	forward_local_port  => $anvil->data->{switches}{'forward-local-port'},
	forward_remote_port => $anvil->data->{switches}{'forward-remote-port'}
}) > 0)
{
	$anvil->nice_exit({ exit_code => 1 });
}

my $is_ssh_tunnel_alive = 1;

while($is_ssh_tunnel_alive)
{
	$is_ssh_tunnel_alive = $ssh_fh->test('echo');

	sleep(60);
}

close_ssh_tunnel();