#!/bin/sh -e

usage () {
    echo "Usage: $0 [-h|--help|-v|--verbose]"
    echo ""
    echo "  -h | --help      print this help"
    echo "  -v | --verbose   be verbose (messages go to STDOUT)"
    echo "  -V | --version   print version information"
    echo "  -D | --debug     debug mode"
    echo ""
    echo " Possible return values:"
    echo "  0  most likely running on a laptop"
    echo "  1  most likely NOT running on a laptop"
    echo "  2  called with unknown option, -h, --help, -V, --version, -D or --debug"
}

PRINTIT="/bin/true" # /bin/true accepts any option but never prints anything
EXIT="exit" # replaced in debug mode by /bin/true

# Check wether we were asked to be verbose

if [ "$1" != "" ]; then
    case "$1" in
        "-v"|"--verbose")
            PRINTIT="echo"
            ;;
        "-V"|"--version")
            echo "Version: 0.16"
            exit 2
            ;;
        "-h"|"--help")
            usage
            exit 2
            ;;
        "-D"|"--debug")
            EXIT="/bin/true"
            set -x
            ;;
        *)
            echo "UNKNOWN OPTION: $1"
            usage
            exit 2
            ;;
    esac
fi

# Are we a mac?
if test -d /proc/pmu; then
        batteries=$(grep Battery /proc/pmu/info | cut -f2 -d:)
        if test "$batteries" -ne 0; then
            $PRINTIT "We're a laptop (Mac: batteries found)" >&2;
            $EXIT 0
        fi
        exit 1
fi

if dmidecode="$(command -v dmidecode)" && [ -r /dev/mem -a -x "$dmidecode" ]
then
        # dmidecode to grab the Chassis type
        dmitype=$("$dmidecode" --string chassis-type)

        if test "$dmitype" = "Notebook" || \
           test "$dmitype" = "Portable" || \
           test "$dmitype" = "Laptop"   || \
           test "$dmitype" = "Hand Held"; then
            $PRINTIT "We're a laptop (dmidecode returned \"$dmitype\")" >&2
            $EXIT 0
        fi

        # turn back on for debugging
        #echo "$dmitype"
fi

if [ -e /sys/devices/virtual/dmi/id/chassis_type ] ; then
    chassis_type="$(cat /sys/devices/virtual/dmi/id/chassis_type)"
    case "$chassis_type" in
        8) # Portable
            $PRINTIT "We're a portable (chassis_type is $chassis_type)" >&2
            $EXIT 0
            ;;
        9) # Laptop
            $PRINTIT "We're a laptop (chassis_type is $chassis_type)" >&2
            $EXIT 0
            ;;
        10) # Notebook
            $PRINTIT "We're a notebook (chassis_type is $chassis_type)" >&2
            $EXIT 0
            ;;
        11) # Hand Held
            $PRINTIT "We're a hand held (chassis_type is $chassis_type)" >&2
            $EXIT 0
            ;;
    esac
fi

# check for non device ACPI batteries
/sbin/modprobe battery 2> /dev/null || true
sysfs_power_supply=/sys/class/power_supply
if [ -d $sysfs_power_supply ]; then
	for power_supply in $(ls $sysfs_power_supply)
	do
		if (
			grep -q Battery $sysfs_power_supply/$power_supply/type 2>/dev/null
		) && (
			! grep -q Device $sysfs_power_supply/$power_supply/scope 2>/dev/null
		)
		then
			$PRINTIT "We're a laptop (non device ACPI batteries found)" >&2
			$EXIT 0
		fi
	done
fi
# old interface:
if [ -d /proc/acpi/battery ]; then
        results=`find /proc/acpi/battery -mindepth 1 -type d`
        if [ ! -z "$results" ]; then
            $PRINTIT "We're a laptop (ACPI batteries found)" >&2
            $EXIT 0
        fi
fi


# check for APM batteries. This sucks, because we'll only get a valid response
# if the laptop has a battery fitted at the time
if [ -f /proc/apm ]; then
    battery=`awk '{print $6}' </proc/apm`
    if [ "$battery" != "0xff" ] && [ "$battery" != "0x80" ]; then
        $PRINTIT "We're a laptop (APM batteries found)" >&2
        $EXIT 0
    fi
fi

$PRINTIT "We're not on a laptop (no relevant hint found)" >&2
$EXIT 1