#!/usr/bin/perl -w

use strict;

my $threshold = $ARGV[0];

#if no value passed to script use default check value of 15% or less
#before we start with the whiny applescript warnings

if (!$threshold) { $threshold = 15; }

my $osascript_name = "/tmp/battery_check.scpt";
my (%plist,$msg);
my @cmd_output = `/usr/sbin/ioreg -p IODeviceTree -n "battery" -w 0`;

#looking for the following string:

#"IOBatteryInfo" = ({"Voltage"=11925,"Flags"=4,"Amperage"=1705,"Capacity"=4149,"Current"=3717})

foreach my $line (@cmd_output)
{
	if ($line =~ /IOBatteryInfo/i) { %plist = &formatBatteryInfo($line); } 
}

#foreach (keys %plist) { print "$_ => $plist{$_} \n"; }

#my $voltage = sprintf("%.2f", ($plist{'Voltage'}/1000));
#this calculates the remaining charge left...
my $percentage = sprintf("%.1f", ($plist{'Current'}/$plist{'Capacity'})*100); 
$msg = "\"Voltage : $plist{'Voltage'}  Amperage: $plist{'Amperage'}\"" . '& return &';
$msg .= "\"Capacity : $plist{'Capacity'} Current: $plist{'Current'}\"" . '& return & return &';
$msg .= "\"Remaining Charge : [$percentage%] \"" . '& return & return';

# need to create an adapter value - user from macosxhints suggests that this is the number 7
# i have non-standard plug, but it is greater than 7, so i'm going with the theory that anything 7+ means
# the laptop is plugged in, so don't give the warning...

#convert any funny numbers to a nice round int
my $adapter = int($plist{'Flags'});

#print "$adapter\n";
#print "percentage: $percentage ... threshold: $threshold\n";
if (($percentage < $threshold) && ($adapter <= 7))
{
	#print "i need to create applescript warning\n\n";
	(my $osascript = <<"eoj") =~ s/^\t+//gm;
	tell application "Finder"
		activate		
		set myAlert to $msg
		display dialog myAlert buttons {"OK","Sleep"} with icon caution default button 1
		if button returned of result = "Sleep" then
		sleep
		end if
	end tell
eoj
	
	open(OUTFILE,">$osascript_name");
	print OUTFILE $osascript;
	close(OUTFILE);
	
	system("osascript $osascript_name");
}
#### SUBS #####

sub formatBatteryInfo
{
	my %plist;
	my $info = shift;
	
	$info =~ s/^.+"IOBatteryInfo"([^\{]+)\{([^\}]+)\}.+/$2/i;
	#sample result from this regex:
	#"Voltage"=11572,"Flags"=4,"Amperage"=1894,"Capacity"=4149,"Current"=3298
	my @name_values = split(/,/,$info);
	foreach my $pair (@name_values)
	{
		if ($pair =~ /"([^"]+)"\s*=\s*(.+)/) { $plist{$1} = $2; }
	}
	
	foreach (keys %plist) 
	{
		unless($_ =~ /Flags/i)
		{ 
			$plist{$_} = sprintf("%.2f", ($plist{$_}/1000)); 
		}
	}
	
	return %plist;
}