#! /usr/bin/perl

#  Copyright (C) 2008 Joey Schulze <joey@infodrom.org>
#
#  This program is free software; you can redistribute it and/or modify
#  it under the terms of the GNU General Public License as published by
#  the Free Software Foundation; version 2 dated June, 1991.
#
#  This program is distributed in the hope that it will be useful,
#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#  GNU General Public License for more details.
#
#  You should have received a copy of the GNU General Public License
#  along with this program;  if not, write to the Free Software
#  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.

# Source: http://www.infodrom.org/Infodrom/tools/munin.html

# Supported configuration:
#
#   [ipmi_fans]
#   user root
#   env.ipmitool /usr/bin/ipmitool

use strict;
use warnings;

my $ipmitool = '/usr/bin/ipmitool';

$ipmitool = $ENV{'ipmitool'} if exists $ENV{'ipmitool'};

sub gather
{
    my %info;

    return undef unless -x $ipmitool;

    if (open (my $ipmi, "$ipmitool sensor|")) {
	while (<$ipmi>) {
	    next unless /^Fan [^|]*(\d+)\s+[^|]*\|\s+(\d+(\.\d+)?)\s+\|/;
	    $info{$1} = $2;
	}
	close $ipmi;
    }
    return undef unless %info;
    return \%info;
}

sub descriptions
{
    my $info = shift;
    my %descr;
    my $gotcha = 0;
    my $fan = 0;

    return undef unless -x $ipmitool;

    if (open (my $ipmi, "$ipmitool -v sdr|")) {
        while (<$ipmi>) {
	    if (/^$/) {
		$gotcha = 0;
		next;
	    }
	    next unless $gotcha || /^Sensor ID\s+:\s+Fan [^|]*(\d+)\s+[^|]*/;

	    if ($gotcha) {
		$descr{$fan} = $1 if /^ Entity ID\s+:\s+[^\(]*\(([^\)]*)\)/;
	    } else {
		$gotcha = 1;
		$fan = $1;
	    }

	}
	close $ipmi;
    }

    return undef unless %descr;
    return \%descr;
}

my $info = gather;
if (@ARGV) {
    if ($ARGV[0] eq 'autoconf' || $ARGV[0] eq 'detect') {
	if ($info) {
	    print "yes\n";
	    exit 0;
	} else {
	    print "no\n";
	    exit 1;
	}
    } elsif ($ARGV[0] eq 'config') {
	exit unless $info;

	my $descr = descriptions $info;
	print "graph_title Fan speed\n";
	print "graph_args -l 0\n";
	print "graph_vlabel rpm\n";
	print "graph_category sensors\n";
	print "graph_info This graph shows the speed of fans active in the machine.\n";
	foreach my $fan (sort keys %$info) {
	    if (defined $descr && exists $descr->{$fan}) {
		printf "fan_%d.label Fan %d (%s)\n", $fan, $fan, $descr->{$fan};
	    } else {
		printf "fan_%d.label Fan %d\n", $fan, $fan;
	    }
	}
	exit 0;
    }
}

foreach my $fan (sort keys %$info) {
    printf "fan_%d.value %9.2f\n", $fan, $info->{$fan};
}