#!/bin/bash

DATTOBD="synosnap"

main()
{
	action="$1"
	case "${action}" in
		configure)
			action_configure $@
		;;
		abort-upgrade)
			action_abort_upgrade $@
		;;
		abort-remove)
			action_abort_remove $@
		;;
		abort-deconfigure)
			action_abort_deconfigure $@
		;;
		*)
			echo "preinst called with unknown argument '$1'" >&2
			exit 1
		;;
	esac

	return $?
}

TEXT_COLOR='\033[0;31m' #Red
BG_COLOR='\033[43m' # Yellow background
NC='\033[0m' # No Color

function echo_highlight() {
    echo -e "${TEXT_COLOR}${BG_COLOR}$1${NC}"
}


update_initrd()
{
	dkms_output=$(dkms status | grep synosnap | grep install)

	kernel_versions=()
	while IFS=',/' read -r -a line_array; do
		kernel_version=$(echo "${line_array[2]}" | tr -d '[:space:]')
		kernel_versions+=("$kernel_version")
	done <<< "$dkms_output"

	echo "Found synosnap installed by dkms in the following kernel versions: ${kernel_versions[@]}"
	echo "Start updating initrd and backup old initrd for these kernel versions..."

	for kernel_version in "${kernel_versions[@]}"; do
		# Find out what the proper filename for initrd
		# if not found the proper initrd name, intrd will be empty string
		for initrd in "initrd.img-$kernel_version" "initramfs-$kernel_version.img" "initrd-$kernel_version.img" "initrd-$kernel_version" ''; do
			[[ $initrd && -f /boot/$initrd ]] && break
		done
		if ! [[ $initrd ]]; then
			# Return if we cannot find an initrd.
			echo_highlight "Warning: Unable to find an initial ram disk that we know how to handle." \
				"Will not try to make an initrd, plesae do it manually."
			return 1
		fi

		# get the size (MB) of the initrd
		initrd_size=$(du -m /boot/$initrd | cut -f1)

		# backup old initrd
		echo "Backing up /boot/$initrd to /boot/$initrd.old-syno"
		cp -fv "/boot/$initrd" "/boot/$initrd.old-syno"
		if [ $? -ne 0 ]; then
			echo_highlight "Failed to backup /boot/$initrd to /boot/$initrd.old-syno"
			echo_highlight "One possible cause is insufficient free space on the /boot volume (at least $initrd_size MB required)."
			return 1
		fi

		echo "Making new /boot/$initrd"
		echo "If next boot fails, revert to /boot/$initrd.old-syno image"

		if type "update-initramfs" &> /dev/null; then
			echo "Configuring update-initramfs, please wait..."
			update-initramfs -u -k $kernel_version
		elif type "mkinitrd" &> /dev/null; then
			echo "Configuring initrd, please wait..."
			mkinitrd -f /boot/$initrd $kernel_version
		fi

		if [ $? -ne 0 ]; then
			echo_highlight "Failed to update /boot/$initrd"
			echo_highlight "One possible cause is insufficient free space on the /boot volume (at least $initrd_size MB required)."
			return 1
		fi
	done


	return 0
}


migrate_data()
{
	exist=$(ls /opt/Synology/ActiveBackupforBusiness/data/snapshot-history-db.sqlite 2>/dev/null || true)

	if [[ -n "$exist" ]];then
		mv /opt/Synology/ActiveBackupforBusiness/data/snapshot-history-db.sqlite /opt/synosnap/snapshot-history-db.sqlite
	fi
}

action_configure()
{
	dattobd_version="$(dpkg-query --show --showformat='${Version}' synosnap)"

	if [ -f /etc/os-release ]; then
		. /etc/os-release
		DISTRO=$ID
		DISTROVER=$VERSION_ID
		if [ "$DISTRO" = "debian" ] && dpkg --compare-versions "$DISTROVER" ge "12"; then
			echo "* Debian 12+ detected, disable DKMS autoinstall"
			# ABB #11026 remove AUTOINSTALL="yes" from dkms.conf
			sed -i '/AUTOINSTALL="yes"/d' /usr/src/${DATTOBD}-${dattobd_version}/dkms.conf
		fi
	fi

	# check env varirable SYNO_AGENT_INSTALL_FOLDER is set or not
	if [ -z "$SYNO_AGENT_INSTALL_FOLDER" ]; then
		echo_highlight "SYNO_AGENT_INSTALL_FOLDER is not set"
		exit 1
	fi

	if [ -f "$SYNO_AGENT_INSTALL_FOLDER/dkms_common.postinst" ]; then
		$SYNO_AGENT_INSTALL_FOLDER/dkms_common.postinst ${DATTOBD} ${dattobd_version}
	else
		echo_highlight "unexpected error: dkms_common.postinst is not found"
		exit 1
	fi

	dkms status | grep synosnap | grep install

	if [ "$?" -ne "0" ];then
		echo "DRIVER_INSTALL_RESULT=1" > /opt/synosnap/result
		exit 1
	fi

	# for reload boot script
	update_initrd

	if [ "$?" -ne "0" ];then
		echo "DRIVER_INSTALL_RESULT=1" > /opt/synosnap/result
		exit 1		
	fi

	echo "DRIVER_INSTALL_RESULT=0" > /opt/synosnap/result


	if [ -f /opt/synosnap/enroll ];then
		. /opt/synosnap/enroll
	fi

	if [ "$ENROLL" == "1" ];then
		echo_highlight "****"
		echo_highlight "secure boot is enabled"
		echo_highlight "please use sudo mokutil --import /opt/synosnap/MOK.der to enroll new key"
		echo_highlight "after enrolled the new key, reboot your device"
		echo_highlight "****"
	else
		modprobe ${DATTOBD}
	fi

	migrate_data

	return 0
}

action_abort_upgrade()
{
	new_version="$2"

	return 0
}

action_abort_remove()
{
	in_favour_package_name="$3"
	new_version="$4"

	return 0
}

action_abort_deconfigure()
{
	in_favour_package_name="$3"
	in_favour_package_version="$4"
	conflicting_package_name="$6"
	conflicting_package_version="$7"

	return 0
}

main $@
exit $?