#!/usr/bin/env bash

# exit if a command fails
set -o errexit

# exit if required variables are not set
set -o nounset

# subshells and functions inherit ERR traps
set -E

# check for dependencies
script_commands="gpg pigz pv rclone"
missing_counter=0
for needed_command in ${script_commands}; do
  if ! hash "${needed_command}" >/dev/null 2>&1; then
    printf "Command not found in PATH: %s\\n" "${needed_command}" >&2
    ((missing_counter++))
  fi
done
if ((missing_counter > 0)); then
  printf "Minimum %d commands are missing in PATH, aborting.\\n" "${missing_counter}" >&2
  exit 1
fi

# store hostname
HOST_NAME="$(hostname)"

# store date
DATE="$(date +%Y-%m-%d)"

# create temporary backup directory
LOCAL_PATH="$(mktemp -d)"

# remove the backup directory on exit
function cleanup {
  rm -rf "${LOCAL_PATH}"
}
trap cleanup EXIT

# retrieve current date
YEAR="$(date +%Y)"
MONTH="$(date +%m)"

# set b2 bucket name prefix
BUCKET_NAME_PREFIX="$(cat "${HOME}"/bin/.backup_prefix.file)"

# set remote backup directory
B2_REMOTE="b2:${BUCKET_NAME_PREFIX}-backups-traefik-${HOST_NAME}"
DROPBOX_REMOTE="dropbox:Backups/Traefik/${HOST_NAME}/${YEAR}-${MONTH}"

# set password file for gpg symmetric encryption
GPG_PASSWORD_FILE="${GPG_PASSWORD_FILE:-"${HOME}/bin/.backup_password.file"}"

# create traefik tarball
TRAEFIK_TARBALL="${LOCAL_PATH}/${DATE}_Traefik.tar.gz.gpg"
cd "${HOME}"/traefik && tar cf - . | pigz -c | gpg --batch --yes --passphrase-file "${GPG_PASSWORD_FILE}" --symmetric --cipher-algo AES256 -z 0 2>/dev/null | pv -t -r -b > "${TRAEFIK_TARBALL}"

# create backup directory on dropbox
rclone mkdir "${DROPBOX_REMOTE}"

# copy files over to dropbox
rclone copy --verbose "${TRAEFIK_TARBALL}" "${DROPBOX_REMOTE}"

# create b2 bucket
rclone mkdir "${B2_REMOTE}"

# copy file to b2 bucket
rclone copy --verbose --fast-list "${TRAEFIK_TARBALL}" "${B2_REMOTE}"