#!/usr/bin/perl

# batmon.pl - sjb (ottaky@ottaky.com) - 18/07/02 - dead simple battery monitor for ACPI (written for Vaio U1, should work for others)
#
# The constant ACPI points to /proc/acpi - you may need to change this if your kernel puts it somewhere else

use constant ACPI => '/proc/acpi';

use constant BATT => ACPI.'/battery/BAT1';
use constant ACAD => ACPI.'/ac_adapter/ACAD';
use constant TEMP => ACPI.'/thermal_zone/ATF0';

my $battinfo  = &getACPIInfo(BATT.'/info')        || die "Couldn't get battery info";
my $battstate = &getACPIInfo(BATT.'/state')       || die "Couldn't get battery status";
my $acadstate = &getACPIInfo(ACAD.'/state')       || die "Couldn't get ac-adapter status";
my $tempstate = &getACPIInfo(TEMP.'/temperature') || die "Couldn't get temperature status";

print "CPU temperature is ".(($$tempstate{'temperature'}) ? $$tempstate{'temperature'}.' C' : 'unknown')."\n";

die "No battery present.\n" if ($$battinfo{'present'} eq 'no');

print "AC Adapter is ".$$acadstate{'state'}."\n".
      "Battery is ".$$battstate{'charging state'}." at $$battstate{'present rate'} mW\n".
      "Battery is ".
      (sprintf "%.2f", (($$battstate{'remaining capacity'} / $$battinfo{'last full capacity'}) * 100)).
      "% charged at $$battstate{'remaining capacity'} mWh\n";

if ($$acadstate{'state'}          eq 'off-line'    &&
    $$battstate{'charging state'} eq 'discharging' &&
    $$battstate{'present rate'}) {

    print "Time to run is approximately ".
          (int(($$battstate{'remaining capacity'} / $$battstate{'present rate'}) * 60)).
          " minutes\n";
}
elsif ($$acadstate{'state'}          eq 'on-line'  &&
       $$battstate{'charging state'} eq 'charging' &&
       $$battstate{'present rate'}) {
       
    print "Time to full charge is approximately ".
          (int((($$battinfo{'last full capacity'} - $$battstate{'remaining capacity'}) / $$battstate{'present rate'}) * 60)).
	  " minutes\n";
    
}
elsif ($$battstate{'charging state'} eq 'charging' &&
       $$battstate{'present rate'}   == 0) {
       
    print "Battery is fully charged\n";
} 
else {
    print "Your battery does not appear to be charging or discharging??\n";
}

sub getACPIInfo ($) {

    my ($interface) = @_;
    my %info;
    
    if (-e $interface) {
	if (open (INTERFACE, $interface)) {
	    while (<INTERFACE>) {
		my ($label,$value) = (m/^([^:]+):\s+(.+)$/);
                $value =~ s/\D//g  if ($value =~ /^\d/);
		$info{$label} = $value;
	    }
	    close (INTERFACE);
	    return (\%info);
	}
    }
    return undef;
}