#!/bin/bash

TOP="${0%/*}/.."
LICENSE="$TOP/LICENSE-BSD"
EXCLUDE=""

show_usage () {
    echo "usage: $0 [options]"
    echo "The possible options are:"
    echo "  --dry-run|-n         Just find files lacking license info."
    echo "  --license|-L <file>  Use file to obtain license text."
    echo "  --git|-g             Add license only to files in the repository."
    echo "  --exclude|-e <pat>   Exclude files matching egrep pattern <pat>."
    echo "  --help|-h            Show this help and exit."
}

fatal () {
    local _err _msg

    _err="$1"
    shift
    _msg="$*"

    echo "fatal error: $_msg"
    exit $_err
}

enlicense () {
    local _file _in _out

    case $1 in
        *-func-info.c)
            return 0
            ;;
    esac

    _file="$1"
    _in="$1.no-license"
    _out="$1.license"

    cp $_file $_in
    echo "Inserting licensing information to $_file..."
    echo "/*"                                    > $_out
    cat $LICENSE | sed 's/^    /  /g;s/^/ * /g' \
                 | sed 's/ *$//g'               >> $_out
    echo " */"                                  >> $_out
    echo ""                                     >> $_out
    cat $_in                                    >> $_out
    cp $_out $_file
}

find_missing_licenses () {
    local _lacking _files _f

    _lacking=""
    if [ -z "$EXCLUDE" ]; then
        _files="`find . -name '*.[hc]'`"
    else
        _files="`find . -name '*.[hc]' | egrep -v -e $EXCLUDE`"
    fi

    for _f in $_files; do
        _f="${_f#./}"
        grep -ql 'Copyright .*Intel .*' $_f
        if [ $? != 0 ]; then
            if [ "$GIT" = "y" ]; then
                git ls-files | grep -q "$_f\$" && _lacking="$_lacking $_f" || :
            else
                _lacking="$_lacking $_f"
            fi
        fi
    done

    echo "$_lacking"
}


DRY_RUN=""
GIT=""

while [ "${1#-}" != "$1" -a -n "$1" ]; do
    case $1 in
        --dry-run|-n)
            DRY_RUN="y"
            ;;
        --license|-L)
            if [ -n "$2" ]; then
                shift
                LICENSE="$1"
            else
                fatal 1 "missing license argument"
            fi
            ;;
        --git|-g)
            GIT="y"
            ;;
        --exclude|-e)
            if [ -n "$2" ]; then
                shift
                EXCLUDE="$1"
            else
                fatal 1 "missing exclusion pattern"
            fi
            ;;
        --help|-h)
            show_usage
            exit 0
            ;;
         *)
            echo "Unknown command line option \'$1\'."
            show_usage
            exit 1
            ;;
    esac
    shift
done

if [ ! -f "$LICENSE" ]; then
    fatal 1 "license file \'$LICENSE\' missing"
fi

pushd $TOP >& /dev/null

lacking="`find_missing_licenses`"

for f in $lacking; do
    if [ "$DRY_RUN" != "y" ]; then
        enlicense $f
    else
        echo "$f is lacking licensing information."
    fi
done