#!/bin/sh
# Requirements : borgbackup

# Read configuration
. /etc/fcn-toolbox/backup.cfg

if [ -z "${LOCAL_DIR}" ]; then
  echo >&2 "LOCAL_DIR is not set.  Aborting.";
  exit 1;
fi

if [ -z "${REMOTE_ENABLE}" ]; then

  echo >&2 "REMOTE_ENABLE is not set.  Aborting.";
  exit 1;

elif [ ${REMOTE_ENABLE} = true ]; then

  if [ -z "${REMOTE_USER}" ]; then
    echo >&2 "REMOTE_USER is not set.  Aborting.";
    exit 1;
  fi

  if [ -z "${REMOTE_HOSTNAME}" ]; then
    echo >&2 "REMOTE_HOSTNAME is not set.  Aborting.";
    exit 1;
  fi

  if [ -z "${REMOTE_DIR}" ]; then
    echo >&2 "REMOTE_DIR is not set.  Aborting.";
    exit 1;
  fi

fi

if [ -z "${PGSQL_EXCLUDE_DATNAME}" ]; then
  PGSQL_EXCLUDE_DATNAME="['template_']"
fi

HOSTNAME=`hostname`
LOCAL_DEST=${LOCAL_DIR}/${HOSTNAME}.borg

DATE=`date +%Y-%m-%d`
BACKUP_NAME="${HOSTNAME}_${DATE}"

# Temporary directory for backup
BACKUP_TEMP="${LOCAL_DIR}/output-daily"

if ! type "borg" > /dev/null; then
  echo >&2 "borgbackup is not installed.  Aborting.";
  exit 1;
fi

if [ -d "${BACKUP_TEMP}" ]; then
  echo >&2 "Directory ${BACKUP_TEMP} already exists.  Aborting.";
  exit 1;
else
  mkdir "${BACKUP_TEMP}"
fi

# Backup ejabberd data if ejabberd_ctl is available
if type "ejabberdctl" > /dev/null; then
  EJABBERD_BACKUP=`mktemp -p ~ejabberd/`
  ejabberdctl backup "$EJABBERD_BACKUP"
  mv "$EJABBERD_BACKUP" $BACKUP_TEMP/ejabberd.backup
fi

# Backup PostgreSQL data if pg_dump is available, and user postgres exists
if type "pg_dump" > /dev/null; then
  if id -u "postgres" > /dev/null 2>&1; then
    PG_DBS=`sudo -i -u postgres psql template1 -t -c "SELECT datname FROM pg_database WHERE NOT datname LIKE ANY(ARRAY${PGSQL_EXCLUDE_DATNAME})"`
    for PG_DB in $PG_DBS
    do
      PG_BACKUP=`sudo -u postgres mktemp -t pg_dump_XXXX`
      sudo -u postgres -i pg_dump -Z3 -Fc "${PG_DB}" > "${PG_BACKUP}"
      mv "${PG_BACKUP}" "${BACKUP_TEMP}/pgsql_${PG_DB}_Fc.dump"
    done
  fi
fi

if [ ! -d "${LOCAL_DEST}" ]; then
  # Initialize local borg repository
  borg init --encryption=none "${LOCAL_DEST}"
fi

# Do local backup
borg create --exclude-from /etc/fcn-toolbox/backup.exclude ${LOCAL_DEST}::${BACKUP_NAME} "${BACKUP_TEMP}" ${BACKUP_DIR_INCL}

# Prune local archives to keep only 7 daily, and 4 weekly, and 3 monthly ones
borg prune --keep-daily=7 --keep-weekly=4 --keep-monthly=3 ${LOCAL_DEST}

if [ ${REMOTE_ENABLE} = true ]; then

  REMOTE_DEST=${REMOTE_DIR}/${HOSTNAME}.borg

  # Quick check of the remote repository before doing a remote backup
  if borg check --repository-only ${REMOTE_USER}@${REMOTE_HOSTNAME}:${REMOTE_DEST}; then
    # Do remote backup
    borg create --exclude-from /etc/fcn-toolbox/backup.exclude ${REMOTE_USER}@${REMOTE_HOSTNAME}:${REMOTE_DEST}::${BACKUP_NAME} "${BACKUP_TEMP}" ${BACKUP_DIR_INCL}
    # Prune remote archives to keep only 7 daily, and 4 weekly, and 3 monthly ones
    borg prune --keep-daily=7 --keep-weekly=4 --keep-monthly=3 ${REMOTE_USER}@${REMOTE_HOSTNAME}:${REMOTE_DEST}
  else
    echo >&2 "Remote repository is missing of corrupted. Try running: "
    echo >&2 "borg init --encryption=none ${REMOTE_USER}@${REMOTE_HOSTNAME}:${REMOTE_DEST}"
  fi

fi

# Delete temporary directory
rm -rf "${BACKUP_TEMP}"