#!/bin/sh

addl()
{
    lines=`wc $1|awk '{print $1}'`
    head -n $lines $2 > $2head.tmp
    diff $1 $2head.tmp >/dev/null 2>/dev/null
    ret=$?
    rm -f $2head.tmp
    if [ $ret -eq 0 ]
    then
        echo "$2 LICENSE ready!"
    elif [ $ret -eq 1 ]
    then
        cat $1 $2 > $2.tmp
        mv $2.tmp $2
        echo "LICENSE file $1 add to $2"
    else
        echo "error"
    fi
}

dell()
{
    lines=`wc $1|awk '{print $1}'`
    head -n $lines $2 > $2head.tmp
    diff $1 $2head.tmp >/dev/null 2>/dev/null
    ret=$?
    rm -f $2head.tmp
    if [ $ret -eq 0 ]
    then
        sed -e "1,$lines d" $2 >$2.tmp
        echo "$2 LICENSE removed!"
        mv $2.tmp $2
    elif [ $ret -eq 1 ]
    then
        echo "LICENSE not found in $2!"
    else
        echo error
    fi
}

if [ $# -lt 3 ]
then
    echo "Usage: lic -a|-d LICENSE.txt files..."
    exit 1
fi

act=$1
licf=$2.tmp
cp $2 $licf
echo "">>$licf

argi=1
for arg in $*
do
    if [ $argi -eq 1 ]
    then
        argi=2
    elif [ $argi -eq 2 ]
    then
        argi=3
    else
        if [ $act = '-a' ]
        then
            addl $licf $arg
        else
            dell $licf $arg
        fi
    fi
done
rm -f $licf
