#!/bin/sh

VERSION=$(cat version)
DATE=$(date +%Y%m%d)

PREFIX=/usr/local
BINDIR="${PREFIX}/bin"
LIBDIR="${PREFIX}/lib"
DOCDIR="${PREFIX}/share/doc"
MANDIR="${PREFIX}/share/man"

BINDIR_set=
LIBDIR_set=
DOCDIR_set=
MANDIR_set=

get_optval(){
    local ret
    case "$1" in
        --*=?*)
            echo "${1:9}"
            ret=0
            ;;
        *)
            echo "${2}"
            ret=1
            ;;
    esac
    return ${ret}
}

set_prefix() {
    local ret
    PREFIX=$(get_optval "$1" "$2")
    ret=$?
    [ -z "${BINDIR_set}" ] && BINDIR="${PREFIX}/bin"
    [ -z "${LIBDIR_set}" ] && LIBDIR="${PREFIX}/lib"
    [ -z "${DOCDIR_set}" ] && DOCDIR="${PREFIX}/share/doc"
    [ -z "${MANDIR_set}" ] && MANDIR="${PREFIX}/share/man"
    return ${ret}
}

set_bindir() {
    local ret
    BINDIR=$(get_optval "$1" "$2")
    ret=$?
    BINDIR_set=1
    return ${ret}
}

set_libdir() {
    local ret
    LIBDIR=$(get_optval "$1" "$2")
    ret=$?
    LIBDIR_set=1
    return ${ret}
}

set_docdir() {
    local ret
    DOCDIR=$(get_optval "$1" "$2")
    ret=$?
    DOCDIR_set=1
    return ${ret}
}

set_mandir() {
    local ret
    MANDIR=$(get_optval "$1" "$2")
    ret=$?
    MANDIR_set=1
    return ${ret}
}

while [ $# -ne 0 ]; do
    case "$1" in
        --prefix*)  set_prefix "$1" "$2" && shift || shift 2;;
        --bindir*)  set_bindir "$1" "$2" && shift || shift 2;;
        --libdir*)  set_libdir "$1" "$2" && shift || shift 2;;
        --docdir*)  set_docdir "$1" "$2" && shift || shift 2;;
        --mandir*)  set_mandir "$1" "$2" && shift || shift 2;;
    esac
done

sed -r -e "s,@@BINDIR@@,${BINDIR},g;"   \
       -e "s,@@LIBDIR@@,${LIBDIR},g;"   \
       -e "s,@@DOCDIR@@,${DOCDIR},g;"   \
       -e "s,@@MANDIR@@,${MANDIR},g;"   \
       -e "s,@@VERSION@@,${VERSION},g;" \
       -e "s,@@DATE@@,${DATE},g;"       \
        Makefile.in >Makefile