#!/bin/bash
#
# .---.                  .              .
# |                      |              |
# |--- .--. .-.  .-.  .-.|  .-. .--.--. |.-.  .-. .--.  .-.
# |    |   (.-' (.-' (   | (   )|  |  | |   )(   )|  | (.-'
# '    '     --'  --'  -' -  -' '  '   -' -'   -' '   -  --'
#
#                    Freedom in the Cloud
#
# Database functions
#
# License
# =======
#
# Copyright (C) 2014-2016 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/>.

# default MariaDB password
MARIADB_PASSWORD=

# Used to indicate whether the backup contains MariaDB databases or not
BACKUP_INCLUDES_DATABASES="no"

# contains the mysql root password which
# is used for backups and repair
DATABASE_PASSWORD_FILE=/root/dbpass

function backup_database_local {
    # Makes local backups of databases which can then be automatically rolled
    # back if corruption is detected
    database_name=$1

    backup_databases_script=/usr/bin/backupdatabases
    echo '' >> $backup_databases_script
    echo "# Backup the ${database_name} database" >> $backup_databases_script
    echo "TEMPFILE=/root/${database_name}.sql" >> $backup_databases_script
    echo 'DAILYFILE=/var/backups/${database_name}_daily.sql' >> $backup_databases_script
    echo "mysqldump --password=\"\$MYSQL_PASSWORD\" ${database_name} > \$TEMPFILE" >> $backup_databases_script
    echo 'FILESIZE=$(stat -c%s $TEMPFILE)' >> $backup_databases_script
    echo 'if [ "$FILESIZE" -eq "0" ]; then' >> $backup_databases_script
    echo '    if [ -f $DAILYFILE ]; then' >> $backup_databases_script
    echo '        cp $DAILYFILE $TEMPFILE' >> $backup_databases_script
    echo '' >> $backup_databases_script
    echo '        # try to restore yesterdays database' >> $backup_databases_script
    echo "        mysql -u root --password=\"\$MYSQL_PASSWORD\" ${database_name} -o < \$DAILYFILE" >> $backup_databases_script
    echo '' >> $backup_databases_script
    echo '        # Send a warning email' >> $backup_databases_script
    echo "        echo \"Unable to create a backup of the ${database_name} database. Attempted to restore from yesterdays backup\" | mail -s \"${database_name} backup\" \$EMAIL" >> $backup_databases_script
    echo '    else' >> $backup_databases_script
    echo '        # Send a warning email' >> $backup_databases_script
    echo "        echo \"Unable to create a backup of the ${database_name} database.\" | mail -s \"${database_name} backup\" \$EMAIL" >> $backup_databases_script
    echo '    fi' >> $backup_databases_script
    echo 'else' >> $backup_databases_script
    echo '    chmod 600 $TEMPFILE' >> $backup_databases_script
    echo '    mv $TEMPFILE $DAILYFILE' >> $backup_databases_script
    echo '' >> $backup_databases_script
    echo '    # Make the backup readable only by root' >> $backup_databases_script
    echo '    chmod 600 $DAILYFILE' >> $backup_databases_script
    echo 'fi' >> $backup_databases_script

    weekly_backup_script=/etc/cron.weekly/backupdatabasesweekly
    if ! grep -q "${database_name}" ${weekly_backup_script}; then
        echo '' >> ${weekly_backup_script}
        echo "# ${database_name}" >> ${weekly_backup_script}
        echo "if [ -f /var/backups/${database_name}_weekly.sql ]; then" >> ${weekly_backup_script}
        echo "  cp -f /var/backups/${database_name}_weekly.sql /var/backups/${database_name}_2weekly.sql" >> ${weekly_backup_script}
        echo 'fi' >> ${weekly_backup_script}
        echo "if [ -f /var/backups/${database_name}_daily.sql ]; then" >> ${weekly_backup_script}
        echo "  cp -f /var/backups/${database_name}_daily.sql /var/backups/${database_name}_weekly.sql" >> ${weekly_backup_script}
        echo 'fi' >> ${weekly_backup_script}
    fi

    monthly_backup_script=/etc/cron.monthly/backupdatabasesmonthly
    if ! grep -q "${database_name}" ${monthly_backup_script}; then
        echo '' >> ${monthly_backup_script}
        echo "# ${database_name}" >> ${monthly_backup_script}
        echo "if [ -f /var/backups/${database_name}_monthly.sql ]; then" >> ${monthly_backup_script}
        echo "  cp -f /var/backups/${database_name}_monthly.sql /var/backups/${database_name}_2monthly.sql" >> ${monthly_backup_script}
        echo 'fi' >> ${monthly_backup_script}
        echo "if [ -f /var/backups/${database_name}_weekly.sql ]; then" >> ${monthly_backup_script}
        echo "  cp -f /var/backups/${database_name}_weekly.sql /var/backups/${database_name}_monthly.sql" >> ${monthly_backup_script}
        echo 'fi' >> ${monthly_backup_script}
    fi

    if ! grep -q "${database_name}" /etc/cron.hourly/repair; then
        echo "${PROJECT_NAME}-repair-database ${database_name}" >> /etc/cron.hourly/repair
        # remove legacy stuff
        sed -i 's|/usr/bin/repairdatabase redmatrix||g' /etc/cron.hourly/repair
    fi
}

function get_mariadb_password {
    if [ -f /home/$MY_USERNAME/README ]; then
        if grep -q "MariaDB password" /home/$MY_USERNAME/README; then
            if [ -f $DATABASE_PASSWORD_FILE ]; then
                MARIADB_PASSWORD=$(cat $DATABASE_PASSWORD_FILE)
            else
                MARIADB_PASSWORD=$(cat /home/$MY_USERNAME/README | grep "MariaDB password" | awk -F ':' '{print $2}' | sed 's/^ *//')
                echo "$MARIADB_PASSWORD" > $DATABASE_PASSWORD_FILE
                chmod 600 $DATABASE_PASSWORD_FILE
            fi
        fi
    fi
}

function install_mariadb {
    if [[ $(is_completed $FUNCNAME) == "1" ]]; then
        return
    fi
    apt-get -yq install python-software-properties debconf-utils
    apt-get -yq install software-properties-common
    apt-get -yq update

    function_check get_mariadb_password
    get_mariadb_password
    if [ ! $MARIADB_PASSWORD ]; then
        if [ -f $IMAGE_PASSWORD_FILE ]; then
            MARIADB_PASSWORD="$(printf `cat $IMAGE_PASSWORD_FILE`)"
        else
            MARIADB_PASSWORD="$(openssl rand -base64 32 | cut -c1-${MINIMUM_PASSWORD_LENGTH})"
        fi
        echo "$MARIADB_PASSWORD" > $DATABASE_PASSWORD_FILE
        chmod 600 $DATABASE_PASSWORD_FILE

        echo '' >> /home/$MY_USERNAME/README
        echo '' >> /home/$MY_USERNAME/README
        echo '# MariaDB / MySql' >> /home/$MY_USERNAME/README
        echo $"Your MariaDB password is: $MARIADB_PASSWORD" >> /home/$MY_USERNAME/README
        echo '' >> /home/$MY_USERNAME/README
        chown $MY_USERNAME:$MY_USERNAME /home/$MY_USERNAME/README
        chmod 600 /home/$MY_USERNAME/README
    fi

    debconf-set-selections <<< "mariadb-server mariadb-server/root_password password $MARIADB_PASSWORD"
    debconf-set-selections <<< "mariadb-server mariadb-server/root_password_again password $MARIADB_PASSWORD"
    apt-get -yq install mariadb-server
    apt-get -yq remove --purge apache*
    if [ -d /etc/apache2 ]; then
        rm -rf /etc/apache2
        echo $'Removed Apache installation after MariaDB install'
    fi

    if [ ! -d /etc/mysql ]; then
        echo $"ERROR: mariadb-server does not appear to have installed. $CHECK_MESSAGE"
        exit 54
    fi

    mysqladmin -u root password "$MARIADB_PASSWORD"
    mark_completed $FUNCNAME
}

function backup_databases_script_header {
    if [ ! -f /usr/bin/backupdatabases ]; then
        # daily
        echo '#!/bin/sh' > /usr/bin/backupdatabases
        echo '' >> /usr/bin/backupdatabases
        echo "EMAIL='$MY_EMAIL_ADDRESS'" >> /usr/bin/backupdatabases
        echo '' >> /usr/bin/backupdatabases
        echo -n 'MYSQL_PASSWORD=$(cat ' >> /usr/bin/backupdatabases
        echo "$DATABASE_PASSWORD_FILE)" >> /usr/bin/backupdatabases
        echo 'umask 0077' >> /usr/bin/backupdatabases
        echo '' >> /usr/bin/backupdatabases
        echo '# exit if we are backing up to friends servers' >> /usr/bin/backupdatabases
        echo "if [ -f $FRIENDS_SERVERS_LIST ]; then" >> /usr/bin/backupdatabases
        echo '  exit 1' >> /usr/bin/backupdatabases
        echo 'fi' >> /usr/bin/backupdatabases
        chmod 600 /usr/bin/backupdatabases
        chmod +x /usr/bin/backupdatabases

        echo '#!/bin/sh' > /etc/cron.daily/backupdatabasesdaily
        echo '/usr/bin/backupdatabases' >> /etc/cron.daily/backupdatabasesdaily
        chmod 600 /etc/cron.daily/backupdatabasesdaily
        chmod +x /etc/cron.daily/backupdatabasesdaily

        # weekly
        echo '#!/bin/sh' > /etc/cron.weekly/backupdatabasesweekly
        echo '' >> /etc/cron.weekly/backupdatabasesweekly
        echo 'umask 0077' >> /etc/cron.weekly/backupdatabasesweekly

        chmod 600 /etc/cron.weekly/backupdatabasesweekly
        chmod +x /etc/cron.weekly/backupdatabasesweekly

        # monthly
        echo '#!/bin/sh' > /etc/cron.monthly/backupdatabasesmonthly
        echo '' >> /etc/cron.monthly/backupdatabasesmonthly
        echo 'umask 0077' >> /etc/cron.monthly/backupdatabasesmonthly

        chmod 600 /etc/cron.monthly/backupdatabasesmonthly
        chmod +x /etc/cron.monthly/backupdatabasesmonthly
    fi
}

function repair_databases_script {
    if [ -f /etc/cron.hourly/repair ]; then
        sed -i "s|/usr/bin/repairdatabase|${PROJECT_NAME}-repair-database|g" /etc/cron.hourly/repair
    fi

    if [[ $(is_completed $FUNCNAME) == "1" ]]; then
        return
    fi

    if [ ! -f $DATABASE_PASSWORD_FILE ]; then
        return
    fi

    echo '#!/bin/bash' > /etc/cron.hourly/repair
    echo '' >> /etc/cron.hourly/repair
    chmod 600 /etc/cron.hourly/repair
    chmod +x /etc/cron.hourly/repair

    mark_completed $FUNCNAME
}

function remove_database {
    app_name="$1"
    if [ ! -d $INSTALL_DIR ]; then
        mkdir $INSTALL_DIR
    fi
    echo "drop database ${app_name};
quit" > $INSTALL_DIR/batch.sql
    chmod 600 $INSTALL_DIR/batch.sql
    mysql -u root --password="$MARIADB_PASSWORD" < $INSTALL_DIR/batch.sql
    shred -zu $INSTALL_DIR/batch.sql
}

function create_database {
    app_name="$1"
    app_admin_password="$2"
    app_admin_username=$3
    if [ ! -d $INSTALL_DIR ]; then
        mkdir $INSTALL_DIR
    fi
    if [ ! $app_admin_username ]; then
        app_admin_username=${app_name}admin
    fi
    echo "create database ${app_name};
CREATE USER '$app_admin_username@localhost' IDENTIFIED BY '${app_admin_password}';
GRANT ALL PRIVILEGES ON ${app_name}.* TO '$app_admin_username@localhost';
quit" > $INSTALL_DIR/batch.sql
    chmod 600 $INSTALL_DIR/batch.sql
    mysql -u root --password="$MARIADB_PASSWORD" < $INSTALL_DIR/batch.sql
    shred -zu $INSTALL_DIR/batch.sql
}

function initialise_database {
    database_name=$1
    database_file=$2
    mysql -u root --password="$MARIADB_PASSWORD" -D $database_name < $database_file
    if [ ! "$?" = "0" ]; then
        exit 62952
    fi
}

function run_query {
    database_name=$1
    database_query=$2
    mysql -u root --password="$MARIADB_PASSWORD" -e "$database_query" $database_name
}

function drop_database {
    database_name=$1
    get_mariadb_password
    mysqladmin -uroot -p"$MARIADB_PASSWORD" -f drop $database_name
}

function database_reinstall {
    apt-get -yq purge mariadb*
    rm -rf /var/lib/mysql
    rm -rf /etc/mysql
    apt-get -yq install mariadb-server
}

# NOTE: deliberately there is no "exit 0"