installroot=$1
destdir=$2

mkdir -p $installroot
touch $installroot/.testcap
if setcap cap_net_raw+p $installroot/.testcap >& /dev/null; then
    capsargs=""
else
    capsargs="--setopt=tsflags=nocapps"
fi
rm $installroot/.testcap
pkglist=$(cat $(dirname $0)/pkglist | tr "\r\n" " ")
mydir=$(dirname $0)
mkdir -p $installroot/proc $installroot/sys $installroot/dev
unshare -f -p -m bash -c "
mount -o bind /proc $installroot/proc
mount -o bind /sys $installroot/sys
mount -o bind /dev $installroot/dev
yum  -y $capsargs --releasever=8  --installroot=$installroot install $pkglist
cp -a $mydir/dracut $installroot/usr/lib/dracut/modules.d/97diskless
chmod a+x $installroot/usr/lib/dracut/modules.d/97diskless/*
"
for kernel in $(ls $installroot/boot/vmlinuz-*|grep -v rescue|sed -e s/.*vmlinuz-//); do
    echo -n "Creating diskless initramfs for $kernel"
    chroot $installroot dracut -v --xz -N -m "diskless base terminfo" -f boot/initramfs-diskless-$kernel.img $kernel
done
latestkernel=$(ls $installroot/boot/vmlinuz-*|grep -v rescue|sed -e s/.*vmlinuz-//|tail -n 1)
mkdir -p $destdir/boot/efi/boot $destdir/boot/initramfs
cp $installroot/boot/vmlinuz-$latestkernel $destdir/boot/kernel 
cp $installroot/boot/initramfs-diskless-$latestkernel.img $destdir/boot/initramfs/distribution
cp $installroot/boot/efi/EFI/BOOT/BOOTX64.EFI $destdir/boot/efi/boot
cp $installroot/boot/efi/EFI/centos/grubx64.efi $destdir/boot/efi/boot

# link kernel, initrd, grub, and shim as appropriate

# use xz, minimize https burden and transfer penalty
mksquashfs $installroot $destdir/rootimg.sfs -comp xz