#!/bin/bash
#
# restic-cron - Runs a Restic backup on the homedir
#
# by Paul van Tilburg <paul@luon.net>

# Nofication function
notify() {
  notify-send -i deja-dup "$1"
  test -z "$RESTIC_QUIET" && echo "I: $1"
}

# Check if a --verbose argument is passed, otherwise use quiet
RESTIC_QUIET="--quiet"
if [ "$1" = "--verbose" ]; then
  RESTIC_QUIET=""
fi

# Allow for connecting to X11 and the SSH agent
export SSH_AUTH_SOCK=/run/user/1000/keyring/ssh
export SSH_AGENT_PID=$(pidof ssh-agent)

# Restic settings
RESTIC_BACKUP_OPTIONS="--exclude-file=$HOME/.config/restic/exclude"
RESTIC_FORGET_OPTIONS="--keep-weekly=4 --keep-monthly=12 --keep-yearly=60"
RESTIC_DIR="$HOME"
export RESTIC_REPOSITORY="sftp://void//media/Backup/entropy"

# Start the backup by asking for the passphrase
notify "Starting backup…"
sleep 3
export RESTIC_PASSWORD=$(zenity --title="Restic backup passphrase" --password)

if [ -z "$RESTIC_PASSWORD" ]; then
  notify "Backup aborted due to empty passphrase or cancellation!"
  exit 1
fi

# Create a new backup
test -z "$RESTIC_QUIET" && echo "I: Backup step…"
restic $RESTIC_QUIET backup $RESTIC_DIR $RESTIC_BACKUP_OPTIONS
status=$?
if [ $status -ne 0 ]; then
  notify "Unable to finish the backup!"
  exit 2
fi

# Forget old snapshots
test -z "$RESTIC_QUIET" && echo "I: Forget step…"
restic $RESTIC_QUIET forget $RESTIC_FORGET_OPTIONS
status=$?
if [ $status -ne 0 ]; then
  echo "E: Exit code was $status"
  notify "Was not able to forget old snapshots!"
  exit 3
fi

# Prune the repository
test -z "$RESTIC_QUIET" && echo "I: Prune step…"
restic $RESTIC_QUIET prune
status=$?
if [ $status -ne 0 ]; then
  echo "E: Exit code was $status"
  notify "Was not able to prune the repository!"
  exit 4
fi

# Verify the backup
test -z "$RESTIC_QUIET" && echo "I: Check step…"
restic $RESTIC_QUIET check
status=$?
if [ $status -ne 0 ]; then
  echo "E: Exit code was $status"
  notify "Repository check of the backup failed!"
  exit 5
fi

notify "Backup finished!"