#!/bin/sh
#
# ver. 1.0
#
# process last output ( calculate sum of time )
#     written by Shuhei Ohkado <shuhei@yl.is.s.u-tokyo.ac.jp>
#
# needs NIS:
#     If you are not in NIS environment, change 'ypcat passwd' to 'cat /etc/passwd'
#

lastnum=10;

usage()
{
    echo "Usage: $0 -num <num>";
    exit;
}

go_out=0;
while [ "X$*" != "X" -a $go_out -eq 0 ];
do
    case $1 in
    -n*)  lastnum=$2; shift 2;;
    -h*)  usage; exit;;
    -a*)  lastnum=-1; shift 1; go_out=1;;
    -*) echo "unknoow option $1"; exit;;
    *) go_out=1;
    esac
done

if [ "X$*" != "X" ]; then
    lastnum=$1
fi

if [ $lastnum -lt 0 ]; then
    lastcom="last";
else
    lastcom="last -$lastnum";
fi

active_user()
{
    ypcat passwd | awk -F: '{print $1,$2}' | \
    while read  user pass
    do
    if [ '\*' != \\$pass ]; then
	echo "$user \c"
    fi
    done
}

ulist=`active_user | tr - _`;

for u in $ulist
do
    us=`echo $u|tr - _`
    eval "T${us}=0"
done

for u in $ulist
do
    eval "T${u}=0"
done

eval $lastcom | awk -F' ' '{print $1, $NF}' | \
{
    while read user time
    do
	user=`echo ${user} | tr - _`
	if [ "X$user" = "Xreboot" -o "X$user" = "Xwtmp" -o "X$user" = "X" ]; then
	    continue;
	fi
	if [ "X$time" = "Xin" ]; then
	    echo "$user is still logged in"
	    continue;
	fi

	eval `echo $time | \
	sed -e\
	's/(\(\([0-9]*\)+\)*\([0-9][0-9]\):\([0-9][0-9]\))/\day=\2;hour=\3;min=\4;/'`

        if [ "X$day" = "X" ]; then
	    day=0;
	fi
	eval 'o=`expr $day \* 24`;o=`expr $o + $hour`;o=`expr $o \* 60`;tot=`expr $o + $min`'
	eval "T$user=\`expr \$T$user + $tot\`"
    done

    for u in $ulist
    do
	tot=`eval "echo \\$T$u"`
	if [ $tot -ne 0 ]; then
	    echo "$u = $tot"
	fi
    done | sort +2 -n
}

exit