#!/usr/bin/perl -w
#
# xmlrpc based munin plugin for monitoring rtorrent's peer count
# prerequisites:
#  - rtorrent 0.7.5 or newer compiled with --with-xmlrpc-c
# check http://libtorrent.rakshasa.no/wiki/RTorrentXMLRPCGuide for further information
#
# written by Gabor Hudiczius
# web: http://projects.cyla.homeip.net/rtwi/wiki/rTorrentOMeter
# email: ghudiczius@gmail.com
#
# 0.2.0 - 080619
#  support for scgi_port and scgi_local
#  configurable via munin env variables
#  initial release
#
#
# Parameters:
#
#	config		required
#
#
# Configurable variables
#
#	src		"socket" when using scgi_socket, or anything else when using scgi_port
#	socket		rTorrent's rpc socket (scgi_local)	- using scgi_local	- needed, when "src" is set to "socket"
#	ip		rTorrent's ip address			- using scgi_port	- needed, when "src" is NOT set to "socket"
#	port		rTorrent's scgi port (scgi_port)	- using scgi_port	- needed, when "src" is NOT set to "socket"
#	category        Change graph category
#
# Configuration example
#
#	[rtom_peers]
#	user username
#	env.src socket
#	env.socket /home/usernametorrent/.socket/rpc.socket
#	env.category Category
#
#	[rtom_peers]
#	env.ip 127.0.0.1
#	env.port 5000
#
#
#%# family=auto


if ( $ARGV[0] and $ARGV[0] eq "config" ) {
	my $category = $ENV{"category"} || "";
	print "graph_title rTorrent peer statistics\n";
	print "graph_args --base 1000 --lower-limit 0\n";
	print "graph_vlabel peers\n";
	print "graph_category filetransfer".${category}."\n";
	print "outgoing.label outgoing\n";
	print "outgoing.draw AREA\n";
	print "outgoing.info number of outgoing connections\n";
	print "incoming.label incoming\n";
	print "incoming.draw STACK\n";
	print "incoming.info number of incoming connections\n";
	print "plain.label plain text\n";
	print "plain.draw LINE2\n";
	print "plain.info number of plain text connections\n";
	print "encrypted.label encrypted\n";
	print "encrypted.draw LINE2\n";
	print "encrypted.info number of encrypted connections\n";
	print "total.label total\n";
	print "total.draw LINE2\n";
	print "total.info total number of connections\n";
 	exit 0;
}

use IO::Socket;

my $src 	= $ENV{"src"} || "";
my $ip		= $ENV{"ip"} || "127.0.0.1";
my $port	= $ENV{"port"} || "5000";
my $socket	= $ENV{"socket"} || "";

# detect rtorrent version
use version;
my $rtorrent_version;
sub rtorrent_version_lower_than {
	if (not length $rtorrent_version){
		if ( ( defined $src ) && ( $src eq "socket" ) ) {
			socket( SOCK, PF_UNIX, SOCK_STREAM, 0 ) or die;
			connect( SOCK, sockaddr_un( $socket ) ) or die $!;
		} else {
			socket( SOCK, PF_INET, SOCK_STREAM, getprotobyname( "tcp" ) );
			connect( SOCK, sockaddr_in( $port, inet_aton( $ip ) ) );
		}
		my $line_version= "<?xml version=\"1.0\" encoding=\"utf-8\"?><methodCall><methodName>system.client_version</methodName></methodCall>";
		my $llen	= length $line_version;
		my $header	= "CONTENT_LENGTH\000${llen}\000SCGI\001\000";
		my $hlen	= length $header;
		$line_version= "${hlen}:${header},${line_version}";
		print SOCK $line_version;
		flush SOCK;
		my $pattern	= qr/<value><string>([0-9.]+)<\/string><\/value>/;
		while ( $line = <SOCK> ) {
			if ( $line =~ /$pattern/ ) {
				$rtorrent_version = $1;
			}
		}
		close (SOCK);
	}
	return version->parse($rtorrent_version) < version->parse($_[0]);
}

my $pattern	= qr/<value><(int|i4|i8|ex\.i8)>(\d+)<\/(int|i4|i8|ex\.i8)><\/value>/;
my $tpattern	= qr/[0-9A-F]{20}/;

my $function_multicall	= rtorrent_version_lower_than('0.9.0') ? 'd.multicall' : 'd.multicall2';
my $function_multicall_arg      = rtorrent_version_lower_than('0.9.0') ? '' : '<param><value><string></string></value></param>';
my $function_hash	= rtorrent_version_lower_than('0.9.0') ? 'd.get_hash=' : 'd.hash=';
my $line		= "<?xml version=\"1.0\" encoding=\"utf-8\"?><methodCall><methodName>$function_multicall</methodName><params>$function_multicall_arg<param><value><string>main</string></value></param><param><value><string>$function_hash</string></value></param><param><value><string>p.multicall=,p.is_encrypted=,p.is_incoming=</string></value></param></params></methodCall>";
my $llen	= length $line;
my $header	= "CONTENT_LENGTH\000${llen}\000SCGI\001\000";
my $hlen	= length $header;
$line		= "${hlen}:${header},${line}";

if ( ( defined $src ) && ( $src eq "socket" ) ) {
	socket( SOCK, PF_UNIX, SOCK_STREAM, 0 );
	connect( SOCK, sockaddr_un( $socket ) );
} else {
	socket( SOCK, PF_INET, SOCK_STREAM, getprotobyname( "tcp" ) );
	connect( SOCK, sockaddr_in( $port, inet_aton( $ip ) ) );
}

print SOCK $line;
flush SOCK;

my $tor = 0;
my $tot = 0;
my $enc = 0;
my $inc = 0;
my $pline = "";
my $ppline = "";
while ( $line = <SOCK> ) {
	if ( $line =~ /$tpattern/ ) {
		$tor += 1;
	} elsif ( $line =~ /$pattern/ ) {
		$tot += 1;
		$enc += $2;
		$line = <SOCK>;
		$line =~ /$pattern/;
		$inc += $2;
	}
	$ppline = $pline;
	$pline = $line;
}
close (SOCK);

my $out = $tot - $inc;
my $pla = $tot - $enc;

print "torrents.value ${tor}\ntotal.value ${tot}\nencrypted.value ${enc}\nplain.value ${pla}\nincoming.value ${inc}\noutgoing.value ${out}\n";

exit;