#!/usr/bin/env bash

main() {
  while getopts ":l:" opt; do
    case "${opt}" in
      l)
        unset VM_FILTER
        IFS="," read -r -a VM_FILTER <<< "$OPTARG"
        ;;
      *)
        usage
        ;;
    esac
  done

  local backup_location="/spool/backups"

  if [[ "${#VM_FILTER[*]}" -gt 0 ]]; then
    backup_vms "$backup_location" "${VM_FILTER[@]}"
  else
    backup_vms "$backup_location"
  fi
}

lxc() {
	local lxc_cmd="${TARGET:-lxc}"
	command "$lxc_cmd" "$@"
}

list_vms() {
	lxc list -c n -f csv,noheader
}

usage() { echo "Usage: ${0##*/} [-l vm1,vm2,...]"; exit 1; }

backup_vms() {
  local backup_location="$1"; shift
  local vms=("$@")

  # when no argument use list of all VMs
  if ((${#vms[@]} == 0)); then
    mapfile -t vms < <(list_vms)
  fi

  for vm in "${vms[@]}"; do
    [[ -n $vm ]] || continue
    start_backup "$vm" "$backup_location"
  done
}

start_backup() {
  local vm=$1
  local backup_base="$2"
  local destination="${backup_base}/${vm}"
  echo "$vm -> $destination"

  # Check destination base exists
  # Check VM folder exists
  # Check if archive already exists
  echo "lxc export "$vm" "$destinationi/${vm}_$(date +"%Y-%m-%d_%H-%M-%S").tar.gz""
  lxc export "$vm" "$destinationi/${vm}_$(date +"%Y-%m-%d_%H-%M-%S").tar.gz"
}

main "$@"