#!/bin/bash

set -e

###
# Fetch information from YNH settings
###
RESTIC_SERVER=$(yunohost app setting restic server)
RESTIC_SERVER_PORT=$(yunohost app setting restic port)
RESTIC_SERVER_USER=$(yunohost app setting restic ssh_user)
RESTIC_PATH=$(yunohost app setting restic backup_path)

RESTIC_PASSWORD="$(yunohost app setting restic passphrase)"
RESTIC_REPOSITORY_BASE=sftp://$RESTIC_SERVER_USER@$RESTIC_SERVER:$RESTIC_SERVER_PORT/$RESTIC_PATH/

RESTIC_COMMAND=/usr/local/bin/restic
LOGFILE=/var/log/restic_backup.log
ERRFILE=/var/log/restic_backup.err

do_need_mount() {
    work_dir="$1"
    name="$2"
    repo="$3"
    size="$4"
    description="$5"
    export RESTIC_PASSWORD
    export RESTIC_REPOSITORY=${RESTIC_REPOSITORY_BASE}/$name

    # On essaie de lister les snapshots, sinon on initialise le depot
    $RESTIC_COMMAND list snapshots > >(tee -a $LOGFILE) 2> >(tee -a $ERRFILE >&2) || $RESTIC_COMMAND init > >(tee -a $LOGFILE) 2> >(tee -a $ERRFILE >&2)
}

do_backup() {

    work_dir="$1"
    name="$2"
    repo="$3"
    size="$4"
    description="$5"
    export RESTIC_PASSWORD
    export RESTIC_REPOSITORY=${RESTIC_REPOSITORY_BASE}/$name
    current_date=$(date +"%d_%m_%y_%H:%M")
    pushd $work_dir
    $RESTIC_COMMAND backup ./ > >(tee -a $LOGFILE) 2> >(tee -a $ERRFILE >&2)
    backup_return_code="$?"
    popd

    # On ne nettoie que si la sauvegarde s'est bien passee
    if [ "$backup_return_code" -eq "0" ];then
        $RESTIC_COMMAND forget --keep-daily 7 --keep-weekly 8 --keep-monthly 12 > >(tee -a $LOGFILE) 2> >(tee -a $ERRFILE >&2)
    else
        echo "Something went wrong during backup" > >(tee -a $ERRFILE >&2)
        exit 1
    fi
}

work_dir=$2
name=$3

size=$5
description=$6

case "$1" in
  need_mount)
    do_need_mount $work_dir $name $repo $size $description
    ;;
  backup)
    do_backup $work_dir $name $repo $size $description
    ;;
  mount)
    do_need_mount $work_dir $name $repo $size $description
    ;;
  *)
    echo "hook called with unknown argument \`$1'" >&2
    exit 1
    ;;
esac

exit 0