#!/bin/bash
if [ "$(id -u)" != 0 ]
then
    exec sudo -- "$0" "$@"
    exit 1
fi

loudly()
{
    (set -x
    "$@")
}

f()
{
    OUTPUT=/boot/initrd.img-$1${OUTPUT_TAG}
    /usr/sbin/mkinitramfs \
         -d /usr/local/lib/samizdat-rhizome/initramfs-tools/ \
         -o "$OUTPUT" \
         -k "$1" || return
    loudly ln -sf "${OUTPUT#/}" /initrd.img
}

OUTPUT_TAG=.samizdat
while [ $# -gt 0 ]
do
    case "$1" in
        -s|--system) OUTPUT_TAG=; shift; continue;;
        --) shift; break;;
        -?) exit 1;;
        *) break;;
    esac
done

if [ "$1" ]
then
    k=/boot/vmlinuz-$1
    if ! [ -e "$k" ]
    then
        printf 'Error: No such file: %s\n' "$k" >&2
    fi
    f "$1" || exit
    ln -sf "vmlinuz-$1" /vmlinuz
elif [ -L /vmlinuz ]
then
    l=$(readlink /vmlinuz)
    v=${l#boot/vmlinuz-}
    [ -e "/boot/vmlinuz-$v" ] || exit
    f "$v"
else
    printf 'Error: Could not determine kernel version.  Create /vmlinuz or specify a version.' >&2
    exit 1
fi