#!/bin/bash
backupcfg="/etc/backup.cfg"

if [ $UID -ne 0 ]; then
	echo "Keine Rootrechte."
	exit 1
fi

input() {
        output=""
        echo "${1}"
        read -r -p "[${2}]: " output
        test -z "${output}" && output="${2}"
        return 0
}

multiplechoice() {
        output=""
        local done=""
        local input=("${@}")
        #for i in $(seq 1 "$(( ${#input[@]} - 1 ))"); do
        for i in $(seq 0 "$(( ${#input[@]} - 1 ))"); do
                if [[ "${i}" == "0" ]]; then
                        choices="${input[$i]}"
                        use="${input[$i]}"
                else
                        choices="${choices}|${input[$i]}"
                        use+=" ${input[$i]}"
                fi
        done
        while input "[${choices}]: " "${input[0]}"; do
                for i in $(seq 0 "${#input[@]}"); do
                        if [[ "${output}" == "${input[$i]}" ]] || [[ "${output}" == "${input[$i]:0:2}" ]]; then
                                output="${input[$i]}"
                                done=1
                        fi
                done
                if [[ -z "${done}" ]]; then
                        echo wronginput "${output}"
                        echo use these: "${use}"
                else
                        break
                fi

        done
}

echo "Bitte Backupgerät noch nicht anschliessen!"
read
DISKS_DETAILS=$(lsblk -l -o KNAME,TYPE,SIZE,MODEL|grep disk)
echo "${DISKS_DETAILS}"
echo ""
echo "Nun das Gerät anschliessen und das neue in der Liste auswaehlen"
read
DISKS_DETAILS=$(lsblk -l -o KNAME,TYPE,SIZE,MODEL|grep disk)
echo "${DISKS_DETAILS}"
multiplechoice $(echo "${DISKS_DETAILS}"|awk '{print $1}')
TARGET_PHY_DISK="/dev/${output}"

parted -a optimal "${TARGET_PHY_DISK}" -s -- mklabel gpt
sleep 5
parted -a optimal "${TARGET_PHY_DISK}" unit mib -s -- mkpart backup btrfs 1 100%
sleep 5
sync

if ! cryptsetup luksFormat "${TARGET_PHY_DISK}1"; then
	echo "Konnte ${TARGET_PHY_DISK} nicht verschluesseln."
	exit 1
else
	UUID="$(lsblk -l -o KNAME,UUID | grep "$(basename ${TARGET_PHY_DISK})1"|awk '{print $2}')"
	if ! cryptsetup open "/dev/disk/by-uuid/${UUID}" "luks-${UUID}"; then
		echo "Konnte /dev/disk/by-uuid/${UUID} nicht oeffnen."
		exit 1
	fi
fi

if ! mkfs.btrfs -f "/dev/mapper/luks-${UUID}"; then
	echo "Konnte /dev/mapper/luks-${UUID} nicht formatieren"
	exit 1
fi

cryptsetup close "luks-${UUID}"

echo "UUID=\"${UUID}\"" > "${backupcfg}"

echo "Erstellen des Containers fertig."