function runMake () {
    run gmake -w -j $(detectNumCPUs) $@
}

function configure () {
    if [[ ! -f configure.ac && ! -f configure.in ]]; then
        echo "ERROR: Neither configure.ac nor configure.in exists in the current directory." >&2
        return 1
    fi

    if [[ ! -f configure ]]; then
        run autoreconf -v -i -f
    fi

    if [[ ! -f "_build/Makefile" ]]; then
        run mkdir -p _build
        run pushd _build
        run ../configure "${configArgs[@]}"
        run popd
    fi
}

function build () {
    configure
    runMake -C "_build" $buildTarget
}

function doc () {
    configure
    runMake -C "_build/$docDirectory" $docTarget
}

function check () {
    build
    runMake -C "_build" check "$@"
}

function clean () {
    run rm -rf "_build"
}

function dist () {
    configure
    runMake -C "_build" dist
}

function install () {
    build
    runMake -C "_build" install
}

function main () {
    local cmd
    case "$1" in
        ""|"build") cmd=build  ;;
        "doc"     ) cmd=doc    ;;
        "check"   ) cmd=check  ;;
        "clean"   ) cmd=clean  ;;
        "dist"    ) cmd=dist   ;;
        "install" ) cmd=install;;
        *)
            echo "Usage: $0 [build | doc | check | clean | dist | install]" >&2
            exit 1
    esac
    if (( $# > 0 )); then
        shift
    fi
    "$cmd" "$@"
}

main "$@"