#! /bin/sh
set -e

# adapted from '/etc/kernel/postinst.d/zz-update-grub and
# /usr/lib/kernel/install.d/90-loaderentry.install, see also
# https://kernel-team.pages.debian.net/kernel-handbook/ch-update-hooks.html



# - cleanup - gently delete all kernels not in kernel-keep-list

if command -V systemd-detect-virt >/dev/null 2>&1 &&
	systemd-detect-virt --quiet --container; then
	exit 0
fi

cleanup() {

	for mount in "${MOUNTROOT}"/* ; do
		if echo "${mount}" | grep -qE '[0-9a-fA-F]{4}-[0-9a-fA-F]{4}' && \
			mountpoint -q "${mount}"; then
			umount "${mount}" || \
			    { warn "umount of ${mount} failed - failure"; exit 0; }
		fi
	done

}

trap cleanup EXIT INT TERM QUIT

. /usr/share/pve-kernel-helper/scripts/functions

LOADER_TITLE="Proxmox Virtual Environment"
if [ -d /etc/pve/ ]; then
	LOADER_TITLE="Proxmox Virtual Environment"
elif [ -d /usr/share/doc/proxmox-mailgateway/ ]; then
	LOADER_TITLE="Proxmox Mailgateway"
elif [ -d /usr/share/doc/proxmox-backup/ ]; then
	LOADER_TITLE="Proxmox Backup Server"
fi

potential_esps(){
	lsblk --list -o PATH,UUID,FSTYPE,PARTTYPE,MOUNTPOINT |
	awk '$3 == "vfat" && $4 == "c12a7328-f81f-11d2-ba4b-00a0c93ec93b" && $5 == "" {print $1,$2}'
}

update_esps() {
	if [ ! -f "${ESP_LIST}" ]; then
	    warn "No ${ESP_LIST} found, skipping ESP sync."
	    exit 0
	fi
	if [ -f /etc/kernel/cmdline ]; then
		CMDLINE="$(cat /etc/kernel/cmdline)"
	else
		warn "No /etc/kernel/cmdline found - falling back to /proc/cmdline"
		# remove initrd entries
		CMDLINE="$(perl -pe 's/\binitrd=([0-9a-zA-Z\\\/.-])*\s*//g;' /proc/cmdline)"
	fi

	loop_esp_list update_esp_func
}

update_esp_func() {
	if ! (echo "${curr_uuid}" | grep -qE '[0-9a-fA-F]{4}-[0-9a-fA-F]{4}'); then
		warn "WARN: ${curr_uuid} read from ${ESP_LIST} does not look like a VFAT-UUID - skipping"
		return
	fi

	path="/dev/disk/by-uuid/$curr_uuid"
	if [ ! -e "${path}" ]; then
		warn "WARN: ${path} does not exist - clean '${ESP_LIST}'! - skipping"
		return
	fi

	mountpoint="${MOUNTROOT}/${curr_uuid}"
	mkdir -p "${mountpoint}" || \
		{ warn "creation of mountpoint ${mountpoint} failed - skipping"; return; }
	mount "${path}" "${mountpoint}" || \
		{ warn "mount of ${path} failed - skipping"; return; }
	if [ -d /sys/firmware/efi ]; then
		if [ ! -f "${mountpoint}/$PMX_LOADER_CONF" ]; then
			warn "${path} contains no loader.conf - skipping"
			return
		fi
		if [ ! -d "${mountpoint}/$PMX_ESP_DIR" ]; then
			warn "${path}/$PMX_ESP_DIR does not exist- skipping"
			return
		fi
	elif [ ! -d "${mountpoint}/grub" ]; then
		warn "${path} contains no grub directory - skipping"
		return
	fi
	warn "Copying and configuring kernels on ${path}"
	copy_and_config_kernels "${mountpoint}"
	if [ -d /sys/firmware/efi ]; then
		remove_old_kernels_efi "${mountpoint}"
	else
		remove_old_kernels_legacy "${mountpoint}"
		mount --bind "${mountpoint}" "/boot"
		update-grub
		umount /boot

	fi

	umount "${mountpoint}" || \
		{ warn "umount of ${path} failed - failure"; exit 0; }

	rmdir "${mountpoint}" || true
}

copy_and_config_kernels() {
	esp="$1"


	for kver in ${BOOT_KVERS}; do

		linux_image="/boot/vmlinuz-${kver}"
		initrd="/boot/initrd.img-${kver}"

		if [ ! -f "${linux_image}" ]; then
			warn "No linux-image ${linux_image} found - skipping"
			continue
		fi
		if [ ! -f "${initrd}" ]; then
			warn "No initrd-image ${initrd} found - skipping"
			continue
		fi

		if [ -d /sys/firmware/efi ]; then

			warn "	Copying kernel and creating boot-entry for ${kver}"
			KERNEL_ESP_DIR="${PMX_ESP_DIR}/${kver}"
			KERNEL_LIVE_DIR="${esp}/${KERNEL_ESP_DIR}"
			mkdir -p "${KERNEL_LIVE_DIR}"
			cp -u --preserve=timestamps "${linux_image}" "${KERNEL_LIVE_DIR}/"
			cp -u --preserve=timestamps "${initrd}" "${KERNEL_LIVE_DIR}/"

			# create loader entry
			cat > "${esp}/loader/entries/proxmox-${kver}.conf" <<- EOF
				title    ${LOADER_TITLE}
				version  ${kver}
				options   ${CMDLINE}
				linux    /${KERNEL_ESP_DIR}/vmlinuz-${kver}
				initrd   /${KERNEL_ESP_DIR}/initrd.img-${kver}
			EOF
		else
			warn "	Copying kernel ${kver}"
			cp -u --preserve=timestamps "${linux_image}" "${esp}/"
			cp -u --preserve=timestamps "${initrd}" "${esp}/"
		fi
	done

}

remove_old_kernels_efi() {
	esp="$1"

	for kerneldir in "${esp}/${PMX_ESP_DIR}"/*; do
		if [ ! -d "${kerneldir}" ]; then
			warn "	${kerneldir} is not a directory - skipping"
			continue
		fi

		kver="$(echo "${kerneldir}" | sed -r "s#^${esp}/${PMX_ESP_DIR}/(.+)\$#\\1#")"

		echo "${BOOT_KVERS}" | grep -q "${kver}" && continue;
		warn "	Removing old version ${kver}"
		rm -rf "${kerneldir}"
		rm -f "${esp}/loader/entries/proxmox-${kver}.conf"
	done

}

remove_old_kernels_legacy() {
	esp="$1"

	for kernel in "${esp}/"vmlinuz-*; do
		kver="$(echo "${kernel}" | sed -r "s#^${esp}/vmlinuz-(.+)\$#\\1#")"

		echo "${BOOT_KVERS}" | grep -q "${kver}" && continue;
		warn "	Removing old version ${kver}"
		rm -rf "${esp}/vmlinuz-${kver}"
		rm -rf "${esp}/initrd.img-${kver}"
	done

}

set -- $DEB_MAINT_PARAMS
mode="${1#\'}"
mode="${mode%\'}"
case $0:$mode in
	# Only run on postinst configure and postrm remove, to avoid wasting
	# time by calling update-grub multiple times on upgrade and removal.
	# Also run if we have no DEB_MAINT_PARAMS, in order to work with old
	# kernel packages.
	*/postinst.d/*:|*/postinst.d/*:configure)
		reexec_in_mountns "$@"
		BOOT_KVERS="$(boot_kernel_list "$@")"
		update_esps
	;;
	 */postrm.d/*:|*/postrm.d/*:remove)
		reexec_in_mountns "$@"
		# no newly installed kernel
		BOOT_KVERS="$(boot_kernel_list)"
		update_esps
	;;
esac

exit 0
