#!/usr/bin/env bash

# Backup MySQL/MariaDB
# default is per table dump, can be set to one full dump
# config override set in borg.backup.mysql.settings
# if run as mysql user, be sure user is in the backup group

# Run -I first to initialize repository
# There are no automatic repository checks unless -C is given

# set last edit date + time
MODULE="mysql"
MODULE_VERSION="1.0.0";

DIR="${BASH_SOURCE%/*}"
if [[ ! -d "$DIR" ]]; then DIR="$PWD"; fi
# init system
. "${DIR}/borg.backup.functions.init.sh";

# include and exclude file
INCLUDE_FILE="borg.backup.mysql.include";
EXCLUDE_FILE="borg.backup.mysql.exclude";
SCHEMA_ONLY_FILE="borg.backup.mysql.schema-only";
# init check file
BACKUP_INIT_CHECK="borg.backup.mysql.init";

# check valid data
. "${DIR}/borg.backup.functions.check.sh";
# if info print info and then abort run
. "${DIR}/borg.backup.functions.info.sh";

# if there is an DB extra config
# on current installs there should be a root or mysql user with unix socket connection
# the script should by run as the mysql or root user (sudo -u mysql ...)
if [ -f "${MYSQL_DB_CONFIG}" ]; then
	# MYSQL_DB_CONFIG='/root/.my.cnf';
	MYSQL_DB_CONFIG_PARAM="--defaults-extra-file=${MYSQL_DB_CONFIG}";
fi;
MYSQL_BASE_PATH='/usr/bin/';
MYSQL_DUMP=${MYSQL_BASE_PATH}'mysqldump';
MYSQL_CMD=${MYSQL_BASE_PATH}'mysql';
# no dump or mysql, bail
if [ ! -f "${MYSQL_DUMP}" ]; then
	echo "[! $(date +'%F %T')] mysqldump binary not found";
	exit 1;
fi;
if [ ! -f "${MYSQL_CMD}" ]; then
	echo "[! $(date +'%F %T')] mysql binary not found";
	exit 1;
fi;
# check that the user can actually do, else abort here
# note: this is the only way to not error
_MYSQL_CHECK=$(mysqladmin ${MYSQL_DB_CONFIG_PARAM} ping 2>&1);
_MYSQL_OK=$(echo "${_MYSQL_CHECK}" | grep "is alive");
if [ -z "${_MYSQL_OK}" ]; then
	echo "[! $(date +'%F %T')] Current user has no access right to mysql database";
	exit 1;
fi;
# below is for file name only
# set DB_VERSION (Distrib n.n.n-type)
# NEW: mysql  Ver 15.1 Distrib 10.5.12-MariaDB, for debian-linux-gnu (x86_64) using  EditLine wrapper
# OLD: mysql  Ver 14.14 Distrib 5.7.35, for Linux (x86_64) using  EditLine wrapper
_DB_VERSION_TYPE=$("${MYSQL_CMD}" --version);
_DB_VERSION=$(echo "${_DB_VERSION_TYPE}" | sed 's/.*Distrib \([0-9]\{1,\}\.[0-9]\{1,\}\)\.[0-9]\{1,\}.*/\1/');
DB_VERSION=$(echo "${_DB_VERSION}" | cut -d " " -f 1);
# temporary until correct type detection is set
DB_TYPE="mysql";
# try to get type from -string, if empty set mysql
# if [[ ${_DB_VERSION_TYPE##*-*} ]]; then
# 	DB_TYPE="mysql";
# else
# 	DB_TYPE=$(echo "${_DB_TYPE}" | sed -e 's/.*[0-9]-\([A-Za-z]\{1,\}\).*/\1/');
# fi;
DB_PORT='3306';
DB_HOST='local';

# those dbs have to be dropped with skip locks (single transaction)
NOLOCKDB="information_schema performance_schema"
NOLOCKS="--single-transaction"
# those tables need to be dropped with EVENTS
EVENTDB="mysql"
EVENTS="--events"

# ALL IN ONE FILE or PER DATABASE FLAG
if [ ! -z "${DATABASE_FULL_DUMP}" ]; then
	SCHEMA_ONLY='';
	schema_flag='data';
	if [ "${DATABASE_FULL_DUMP}" = "schema" ]; then
		SCHEMA_ONLY='--no-data';
		schema_flag='schema';
	fi;
	echo "--- [all databases: $(date +'%F %T')] --[${MODULE}]------------------------------------>";
	# We only do a full backup and not per table backup here
	# Filename
	FILENAME="all-${schema_flag}-${DB_TYPE}_${DB_VERSION}_${DB_HOST}_${DB_PORT}.sql"
	# backup set:
	BACKUP_SET_NAME="all-${schema_flag}-${BACKUP_SET}";
	BACKUP_SET_PREFIX="all-";
	# borg call
	BORG_CALL=$(echo "${_BORG_CALL}" | sed -e "s/##FILENAME##/${FILENAME}/" | sed -e "s/##BACKUP_SET##/${BACKUP_SET_NAME}/");
	BORG_PRUNE=$(echo "${_BORG_PRUNE}" | sed -e "s/##BACKUP_SET_PREFIX##/${BACKUP_SET_PREFIX}/");
	if [ ${DEBUG} -eq 1 ] || [ ${DRYRUN} -eq 1 ]; then
		echo "export BORG_BASE_DIR=\"${BASE_FOLDER}\";";
		echo "${MYSQL_DUMP} ${MYSQL_DB_CONFIG_PARAM} --all-databases --create-options --add-drop-database --events ${SCHEMA_ONLY} | ${BORG_CALL}";
		echo "${BORG_PRUNE}";
	fi;
	if [ ${DRYRUN} -eq 0 ]; then
		${MYSQL_DUMP} ${MYSQL_DB_CONFIG_PARAM} --all-databases --create-options --add-drop-database --events ${SCHEMA_ONLY} | ${BORG_CALL};
		_backup_error=$?;
		if [ $_backup_error -ne 0 ]; then
			echo "[! $(date +'%F %T')] Backup creation failed for full dump with error code: ${_backup_error}";
			exit $_backup_error;
		fi;
	fi;
	echo "Prune repository with keep${KEEP_INFO:1}";
	${BORG_PRUNE};
else
	${MYSQL_CMD} ${MYSQL_DB_CONFIG_PARAM} -B -N -e "show databases" |
	while read db; do
		echo "--- [${db}: $(date +'%F %T')] --[${MODULE}]------------------------------------>";
		# exclude checks
		include=0;
		if [ -s "${BASE_FOLDER}${INCLUDE_FILE}" ]; then
			while read incl_db; do
				if [ "${db}" = "${incl_db}" ]; then
					include=1;
					break;
				fi;
			done<"${BASE_FOLDER}${INCLUDE_FILE}";
		else
			include=1;
		fi;
		exclude=0;
		if [ -f "${BASE_FOLDER}${EXCLUDE_FILE}" ]; then
			while read excl_db; do
				if [ "${db}" = "${excl_db}" ]; then
					exclude=1;
					break;
				fi;
			done<"${BASE_FOLDER}${EXCLUDE_FILE}";
		fi;
		if [ ${include} -eq 1 ] && [ ${exclude} -eq 0 ]; then
			# lock check
			nolock='';
			for nolock_db in $NOLOCKDB;
			do
				if [ "$nolock_db" = "$db" ];
				then
					nolock=$NOLOCKS;
				fi;
			done;
			# event check
			event='';
			for event_db in $EVENTDB;
			do
				if [ "$event_db" = "$db" ];
				then
					event=$EVENTS;
				fi;
			done;
			# set dump type
			SCHEMA_ONLY=''; # empty for all
			schema_flag='data'; # or data
			if [ -s "${BASE_FOLDER}${SCHEMA_ONLY_FILE}" ]; then
				while read schema_db; do
					if [ "${db}" = "${schema_db}" ]; then
						SCHEMA_ONLY='--no-data';
						schema_flag='schema';
						# skip out
						break;
					fi;
				done<"${BASE_FOLDER}${SCHEMA_ONLY_FILE}";
			fi;
			# prepare borg calls
			FILENAME="${db}-${schema_flag}-${DB_TYPE}_${DB_VERSION}_${DB_HOST}_${DB_PORT}.sql"
			# backup set:
			BACKUP_SET_NAME="${db}-${schema_flag}-${BACKUP_SET}";
			BACKUP_SET_PREFIX="${db}-"
			# borg call
			BORG_CALL=$(echo "${_BORG_CALL}" | sed -e "s/##FILENAME##/${FILENAME}/" | sed -e "s/##BACKUP_SET##/${BACKUP_SET_NAME}/");
			BORG_PRUNE=$(echo "${_BORG_PRUNE}" | sed -e "s/##BACKUP_SET_PREFIX##/${BACKUP_SET_PREFIX}/");
			# debug or dry run
			if [ ${DEBUG} -eq 1 ] || [ ${DRYRUN} -eq 1 ]; then
				echo "export BORG_BASE_DIR=\"${BASE_FOLDER}\";";
				echo "${MYSQL_DUMP} ${MYSQL_DB_CONFIG_PARAM} $nolock $event --opt ${SCHEMA_ONLY} --add-drop-database --databases ${db} | ${BORG_CALL};"
			fi;
			# backup
			if [ ${DRYRUN} -eq 0 ]; then
				$MYSQL_DUMP ${MYSQL_DB_CONFIG_PARAM} $nolock $event --opt ${SCHEMA_ONLY} --add-drop-database --databases ${db} | ${BORG_CALL};
				_backup_error=$?;
				if [ $_backup_error -ne 0 ]; then
					echo "[! $(date +'%F %T')] Backup creation failed for ${db} dump with error code: ${_backup_error}";
					exit $_backup_error;
				fi;
			fi;
			echo "Prune repository prefixed ${BACKUP_SET_PREFIX} with keep${KEEP_INFO:1}";
			${BORG_PRUNE};
		else
			echo "- [E] ${db}";
		fi;
	done;
fi;

. "${DIR}/borg.backup.functions.close.sh";

# __END__