#!/bin/bash
## File: cloud_backup.sh
## This automates backup of your nextcloud.
## Run as a backup user with the group rights of www-data and the ricght to sudo as that user.
## Within mariadb an user should exist, which has read permissions to everything, but only that!

source ~/.config/cloud_backup.conf

## Returns the binaries full path if existent.
function which_is() {
	declare -n RETVAL=$1;  # declare RETVAL a reference of $1
	local EXECUTABLE=$2;
	local WITHFULLPATH=$(which ${EXECUTABLE} 2>/dev/null);
	if [ -x "$WITHFULLPATH" ]; then
		RETVAL="$WITHFULLPATH";
		return 0;
	else
		RETVAL="$EXECUTABLE not found!";
		return 1;
	fi
}

## Log levels for messages
LLMUTE=0
LLMDTRY=1
LLERROR=2
LLWARNING=3
LLINFO=4
LLDEBUG=5
## Actual log level of the logger used
LOGLEVEL=$LLDEBUG

## Write log of the script
function logger() {
	local LOGGINGLEVEL=$1;
	local LOGMESSAGE=$2;
	local _NOW=$($DATE +%Y%m%d_%H:%M:%S);
	if [[ $LOGLEVEL -ge $LOGGINGLEVEL ]]; then
		echo "cloud_backup $_NOW: ${LOGMESSAGE}" >> $LOGFILE;
	fi
	if [[ $LOGLEVEL -eq $LLDEBUG ]]; then
		echo "cloud_backup $_NOW: ${LOGMESSAGE}";
	fi
}

## updates nextcloud files cache for a given path
## $1 Path to update nextcloud filescache on.
##    Attention: path is relative to nextcloud data folder without '/'!
## return 0 in case of success, 1 on fail.
update_filescache() {
	local CLOUDPATH=$1;
	logger $LLINFO "Updating file cache for $CLOUDPATH.";
	logger $LLDEBUG "$SUDO -u www-data $PHP ${CONFIG_NC_BASE}occ files:scan --path=\"$CLOUDPATH\"";
	$SUDO -u www-data $PHP ${CONFIG_NC_BASE}occ files:scan --path="$CLOUDPATH";
	return $?;
}

## Cleanup and exit with exit value given.
function clean_up() {
	local EXITVAL=$1;
	logger $LLINFO "Cleaning up on exit $EXITVAL.";
	# re-enable the cloud under all circumstances!
	logger $LLINFO "Re-enabling cloud, switching maintenance mode off.";
	$SUDO -u www-data $PHP ${CONFIG_NC_BASE}occ maintenance:mode --off;
	logger $LLINFO "Making log file $CONFIG_NC_LOGPATH visible to cloud.";
	update_filescache ${CONFIG_NC_LOGPATH}; # make logfile visible in cloud
	if [ $? -ne 0 ]; then logger $LLWARNING "Could not update files cache of nextcloud!"; fi
	logger $LLMDTRY "Exiting on $EXITVAL.";
	exit $EXITVAL;
}

#echo "Levels $LLMUTE $LLMDTRY $LLERROR $LLWARNING $LLINFO $LLDEBUG Loglevel: $LOGLEVEL";

## Check binaries availability
which_is SUDO 'sudo';
if [ $? -ne 0 ]; then echo $SUDO; exit 1; fi

which_is DATE 'date';
if [ $? -ne 0 ]; then echo $DATE; exit 1; fi

which_is MYSQLDUMP 'mysqldump';
if [ $? -ne 0 ]; then echo $MYSQLDUMP; exit 1; fi

which_is RSYNC 'rsync';
if [ $? -ne 0 ]; then echo $RSYNC; exit 1; fi

which_is LN 'ln';
if [ $? -ne 0 ]; then echo $LN; exit 1; fi

which_is RM 'rm';
if [ $? -ne 0 ]; then echo $RM; exit 1; fi

which_is SSH 'ssh';
if [ $? -ne 0 ]; then echo $SSH; exit 1; fi

which_is PHP 'php';
if [ $? -ne 0 ]; then echo $PHP; exit 1; fi

which_is TOUCH 'touch'
if [ $? -ne 0 ]; then echo $TOUCH; exit 1; fi

which_is CHOWN 'chown'
if [ $? -ne 0 ]; then echo $CHOWN; exit 1; fi

# Add slash to paths if missing
if [ "${BACKUP_TARGET:${#BACKUP_TARGET}-1:1}" != "/" ]; then
  BACKUP_TARGET=$BACKUP_TARGET/
fi

if [ "${CONFIG_NC_DATA:${#CONFIG_NC_DATA}-1:1}" != "/" ]; then
  CONFIG_NC_DATA=$CONFIG_NC_DATA/
fi

if [ "${CONFIG_NC_BASE:${#CONFIG_NC_BASE}-1:1}" != "/" ]; then
  CONFIG_NC_BASE=$CONFIG_NC_BASE/
fi
if [ "${CONFIG_NC_LOGPATH:${#CONFIG_NC_LOGPATH}-1:1}" != "/" ]; then
  CONFIG_NC_LOGPATH=$CONFIG_NC_LOGPATH/
fi

## Logfile in nextcloud to have a visible result.
RUNDATE=$($DATE +%Y_%m_%d)
LOGFILE="$CONFIG_NC_DATA$CONFIG_NC_LOGPATH${RUNDATE}_cloudbackup.log";
$TOUCH ${LOGFILE};
if [ $? -ne 0 ]; then
  echo "Could not create log file! exiting.";
  exit 1;
fi
logger $LLINFO "Chown logfile $LOGFILE.";
$CHOWN :www-data ${LOGFILE};
if [ $? -ne 0 ]; then
  logger $LLWARNING "Cloud not set group ownership of log file."; # The logfile may not appaer in the clouds dedicated folder.
  exit 1;
fi

logger $LLINFO "Making log file $CONFIG_NC_LOGPATH visible to cloud.";
update_filescache $CONFIG_NC_LOGPATH; # make logfile visible in cloud
if [ $? -ne 0 ]; then
  logger $LLWARNING "Could not update files cache of nextcloud!";
fi

TODAY=$($DATE +%y%m%d_%H%M)

logger $LLMDTRY "Starting backup for ${TODAY}.";
## Let nextcloud enter maintenance mode
logger $LLDEBUG "$SUDO -u www-data $PHP ${CONFIG_NC_BASE}occ maintenance:mode --on;";
logger $LLINFO "Enabling maintenance mode of nextcloud.";
$SUDO -u www-data $PHP ${CONFIG_NC_BASE}occ maintenance:mode --on;
if [[ "$?" != "0" ]]; then logger $LLERROR "Setting nextcloud maintenance mode failed!"; clean_up 1; fi
## Dump mariadb
logger $LLDEBUG "$MYSQLDUMP --single-transaction -h ${CONFIG_NC_DB_SERVER} -u ${CONFIG_NC_DB_USER} -p${CONFIG_NC_DB_PASSWD} ${CONFIG_NC_DB_NAME} > $CONFIG_NC_DATA/${TODAY}_nextcloud.sqlbkp;";
logger $LLINFO "Dumping nextcloud database.";
$MYSQLDUMP --single-transaction -h ${CONFIG_NC_DB_SERVER} -u ${CONFIG_NC_DB_USER} ${CONFIG_NC_DB_NAME} > $CONFIG_NC_DATA/${TODAY}_nextcloud.sqlbkp;
if [[ "$?" != "0" ]]; then logger $LLERROR "Dump of the nextcloud database failed!"; clean_up 1; fi
## Connect to Borg Repo and backup the:
## - config folder,
## - data folder,
## - theme folder,
## - dumped database

# Simple backup with rsync
# local-mode, tossh-mode, fromssh-mode

### do not edit ###
RSYNCCONF=(--delete)

LAST="last"; INC="--link-dest=$BACKUP_TARGET$LAST"

if [ "$SSHUSER" ] && [ "$SSHPORT" ]; then
  S="$SSH -p $SSHPORT -l $SSHUSER";
else
  logger $LLERROR "Invalid ssh command, port or user: »$SSH« »$SSHPORT« «$SSHUSER«";
  clean_up 1;
fi

for SOURCE in "${BACKUP_SOURCES[@]}"; do
  logger $LLDEBUG "$RSYNC -e $S --exclude-from=$CONFIG_EXCLUDE -avR $SOURCE ${RSYNCCONF[@]} $TOSSH:$BACKUP_TARGET$TODAY $INC";
  logger $LLINFO "Rsyncing $SOURCE.";
  $RSYNC -e "$S" --exclude-from=$CONFIG_EXCLUDE -avR "$SOURCE" "${RSYNCCONF[@]}" "$TOSSH:$BACKUP_TARGET$TODAY" $INC;
  if [ $? -ne 0 ]; then logger $LLERROR "Rsync of $SOURCE failed!"; fi
done
if [ "$S" ] && [ "$TOSSH" ] && [ -z "$FROMSSH" ]; then
  logger $LLDEBUG "$S $TOSSH $LN -nsf $BACKUP_TARGET$TODAY $BACKUP_TARGET$LAST";
  logger $LLINFO "Setting Link to last to »$BACKUP_TARGET$TODAY«";
  $S $TOSSH "$LN -nsf $BACKUP_TARGET$TODAY $BACKUP_TARGET$LAST";
  if [ $? -ne 0 ]; then logger $LLERROR "Resetting link to last backup of todays failed!"; clean_up 1; fi
fi
logger $LLMDTRY "Backup of nextcloud done, cleaning up.";

#if [[ "$?" != "0" ]]; then $(logger 1 "Borgbackup of the nextcloud data folder failed!"); exit 1; fi
#if [[ "$?" != "0" ]]; then $(logger 1 "Borgbackup of the nextcloud database failed!"); exit 1; fi

## End maintenance mode of nextcloud end exit 0
clean_up 0;
## EOF