#!/bin/bash
#
# .---.                  .              .
# |                      |              |
# |--- .--. .-.  .-.  .-.|  .-. .--.--. |.-.  .-. .--.  .-.
# |    |   (.-' (.-' (   | (   )|  |  | |   )(   )|  | (.-'
# '    '     --'  --'  -' -  -' '  '   -' -'   -' '   -  --'
#
#                    Freedom in the Cloud
#
# Checks and repairs a given database

# License
# =======
#
# Copyright (C) 2015-2016 Bob Mottram <bob@freedombone.net>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

PROJECT_NAME='freedombone'
COMPLETION_FILE=$HOME/${PROJECT_NAME}-completed.txt
CONFIG_FILE=$HOME/${PROJECT_NAME}.cfg

export TEXTDOMAIN=${PROJECT_NAME}-repair-databases
export TEXTDOMAINDIR="/usr/share/locale"

# The database to be repaired
DATABASE=$1

ADMIN_USERNAME=$(cat $COMPLETION_FILE | grep "Admin user" | awk -F ':' '{print $2}')
ADMIN_EMAIL_ADDRESS=${ADMIN_USERNAME}@${HOSTNAME}

# Frequency - daily/weekly
BACKUP_TYPE='daily'


# migrate from database password file to using the password store
DATABASE_PASSWORD_FILE=/root/dbpass
if [ -f $DATABASE_PASSWORD_FILE ]; then
    MARIADB_PASSWORD=$(cat $DATABASE_PASSWORD_FILE)
    ${PROJECT_NAME}-pass -u root -a mariadb -p "$MARIADB_PASSWORD"
    stored_password=$(${PROJECT_NAME}-pass -u root -a mariadb)
    if [[ "$stored_password" == "$MARIADB_PASSWORD" ]]; then
        shred -zu $DATABASE_PASSWORD_FILE
    fi
fi

MYSQL_ROOT_PASSWORD=$(${PROJECT_NAME}-pass -u root -a mariadb)

TEMPFILE=/root/repair-database-$DATABASE

umask 0077

if [ $2 ]; then
    BACKUP_TYPE=$2
fi

# check the database
mysqlcheck -c -u root --password="$MYSQL_ROOT_PASSWORD" $DATABASE > $TEMPFILE

# Attempt to repair the database if it contains errors
if grep -q "Error" "$TEMPFILE"; then
    mysqlcheck -u root --password="$MYSQL_ROOT_PASSWORD" --auto-repair $DATABASE
else
    # No errors were found, so exit
    rm -f $TEMPFILE
    exit 0
fi
rm -f $TEMPFILE

# Check the database again
mysqlcheck -c -u root --password="$MYSQL_ROOT_PASSWORD" $DATABASE > $TEMPFILE

# If it still contains errors then restore from backup
if grep -q "Error" "$TEMPFILE"; then
    mysql -u root --password="$MYSQL_ROOT_PASSWORD" $DATABASE -o < /var/backups/${DATABASE}_${BACKUP_TYPE}.sql

    # Send a warning email
    echo $"$DATABASE database corruption could not be repaired. Restored from backup." | mail -s $"${PROJECT_NAME} database maintenance" $ADMIN_EMAIL_ADDRESS
    rm -f $TEMPFILE

    exit 1
fi
rm -f $TEMPFILE

exit 0