#!/bin/bash

##
## Install i-doit on a GNU/Linux operating system
##

##
## Copyright (C) 2017-22 synetics GmbH, <https://i-doit.com/>
##
## 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/>.
##

set -euo pipefail
IFS=$'\n\t'

##
## Configuration
##
## You **should not** edit these settings.
## You will be asked for your preferred settings.
## To overwrite these settings export them before running this script.
## For example:
##     export MARIADB_INNODB_BUFFER_POOL_SIZE=2G
##     ./idoit-install
##

: "${MARIADB_HOSTNAME:="localhost"}"
: "${MARIADB_SUPERUSER_USERNAME:="root"}"
: "${MARIADB_SUPERUSER_PASSWORD:="idoit"}"
: "${MARIADB_INNODB_BUFFER_POOL_SIZE:="1G"}"
: "${IDOIT_ADMIN_CENTER_PASSWORD:="admin"}"
: "${MARIADB_IDOIT_USERNAME:="idoit"}"
: "${MARIADB_IDOIT_PASSWORD:="idoit"}"
: "${IDOIT_DEFAULT_TENANT:="CMDB"}"
: "${INSTALL_DIR:="/var/www/html"}"
: "${UPDATE_FILE_PRO:="https://i-doit.com/updates.xml"}"
: "${UPDATE_FILE_OPEN:="https://i-doit.org/updates.xml"}"
: "${UPDATE_FILE_EVAL:="https://eval-downloads.i-doit.com/idoit-eval-automatic.zip"}"
: "${SCRIPT_SETTINGS:="/etc/i-doit/i-doit.sh"}"
: "${CONSOLE_BIN:="/usr/local/bin/idoit"}"
: "${JOBS_BIN:="/usr/local/bin/idoit-jobs"}"
: "${CRON_FILE:="/etc/cron.d/i-doit"}"
: "${BACKUP_DIR:="/var/backups/i-doit"}"
: "${RECOMMENDED_PHP_VERSION:="8.0"}"
: "${RECOMMENDED_MARIADB_VERSION:="10.6"}"

##
## Runtime settings
##
## DO NOT EDIT THESE SETTINGS.
##

OS=""
DATE="$(date +%Y-%m-%d)"
TMP_DIR="/tmp/i-doit_${DATE}"
APACHE_USER="www-data"
APACHE_GROUP="www-data"
MIN_CPU_CORES=2
## Be tolerant, use 1000 instead of 1024:
MIN_RAM=$((1000 * 1000 * 1000 * 2))
APACHE_UNIT=""
MARIADB_UNIT=""
MEMCACHED_UNIT=""
PHP_FPM_UNIT=""
APACHE_CONFIG_FILE=""
MARIADB_CONFIG_FILE=""
PHP_CONFIG_FILE=""
MARIADB_SOCKET=""
PHP_FPM_SOCKET=""
APACHE_HTACCESS_SUBSTITUTION="## Insert content from .htaccess file"
BASENAME=$(basename "$0")
PROJECT_VERSION="0.14-dev"

MARIADB_BIN=""
SUDO_BIN=""
UNZIP_BIN=""
WGET_BIN=""
PHP_BIN=""

## /etc/os-release comes with these variables:
## NAME, VERSION, VERSION_ID, PRETTY_NAME and some more…
NAME=""
VERSION=""
VERSION_ID=""
PRETTY_NAME=""

##--------------------------------------------------------------------------------------------------

function execute {
    local status=0
    local ip_address=""

    log "Install i-doit on a GNU/Linux operating system"
    log ""
    log "Attention:"
    log "This script alters your OS. It will install new packages and will change configuration settings."
    log "Only use it on a fresh installation of a GNU/Linux OS."
    log "It comes with absolutely no warranty."
    log "Read the documentation carefully before you continue:"
    log ""
    log "    https://github.com/i-doit/scripts"
    log ""
    log "This script will automatically…"
    log ""
    log "    1) install additional distribution packages,"
    log "    2) alter configuration of your PHP environment,"
    log "    3) alter configuration of your Apache Web server,"
    log "    4) alter configuration of your MariaDB DBMS, and"
    log "    5) download and install the latest version of i-doit pro or open"
    log "    6) deploy cron jobs and an easy-to-use CLI tool for your i-doit instance"
    log "    7) deploy scripts to backup and restore your i-doit instance"
    log ""
    log "You may skip any step if you like."
    log ""

    askYesNo "Do you really want to continue?" || cancel

    log "\\n--------------------------------------------------------------------------------\\n"

    identifyOS

    log "\\n--------------------------------------------------------------------------------\\n"

    checkHardwareRequirements

    log "\\n--------------------------------------------------------------------------------\\n"

    log "This script needs Web access (HTTP/HTTPS on ports 80/443)."
    askNoYes "Do you want to configure a proxy server?" || configureProxy

    log "\\n--------------------------------------------------------------------------------\\n"

    askYesNo "Do you want to configure the operating system?" && configureOS

    log "\\n--------------------------------------------------------------------------------\\n"

    checkSoftwareRequirements

    log "\\n--------------------------------------------------------------------------------\\n"

    askYesNo "Do you want to configure the PHP environment?" && configurePHP && configurePHPFPM

    log "\\n--------------------------------------------------------------------------------\\n"

    askYesNo "Do you want to configure the Apache Web server?" && configureApache

    log "\\n--------------------------------------------------------------------------------\\n"

    askYesNo "Do you want to configure MariaDB?" && configureMariaDB

    log "\\n--------------------------------------------------------------------------------\\n"

    if askYesNo "Do you want to download and install i-doit automatically?"; then
        prepareIDoit
        updateApacheConfig
        installIDoit

        ip_address=$(ip route get 1 | sed 's/^.*src \([^ ]*\).*$/\1/;q')

        log "Your setup is ready. Navigate to"
        log ""
        log "    http://${ip_address}/"
        log ""
        log "with your Web browser and login to the Admin Center 'admin' to create Tenants manually"

        log "\\n--------------------------------------------------------------------------------\\n"

        askYesNo "Do you want to create the initial i-doit tenant automatically?" && create_tenant

        status=1
    else
        log "Your operating system is prepared for the installation of i-doit."
        log "To complete the setup please follow the instructions as described in the i-doit Knowledge Base:"
        log ""
        log "    https://kb.i-doit.com/display/en/Setup"
    fi

    if [[ "$status" = 1 ]]; then
        log "\\n--------------------------------------------------------------------------------\\n"

        if askYesNo "Do you want to configure i-doit cron jobs?"; then
            deployScriptSettings
            deployConsole
            deployJobScript
            deployCronJobs

            log "Cron jobs are successfully activated. To change e-mail address, execution date and time please edit this file:"
            log ""
            log "    $CRON_FILE"
            log ""
            log "There is also a script available for all system users to execute the i-doit console command line tool:"
            log ""
            log "    idoit"
            log ""
            log "The needed cron jobs are defined here:"
            log ""
            log "    $JOBS_BIN"
            log ""
            log "If needed you can change the settings of both the i-doit console and the cron jobs:"
            log ""
            log "    $SCRIPT_SETTINGS"

            status=2
        fi
    fi

    if [[ "$status" = 2 ]]; then
        log "\\n--------------------------------------------------------------------------------\\n"

        if askYesNo "Do you want to backup i-doit automatically?"; then
            deployBackupAndRestore

            log "Backups are successfully activated. Each night a backup will be created."
            log "Backups will be kept for 30 days:"
            log ""
            log "    $BACKUP_DIR"
            log ""
            log "You may create a backup manually:"
            log ""
            log "    idoit-backup"
            log ""
            log "Of course, you are able to restore i-doit from the lastest backup:"
            log ""
            log "    idoit-restore"
            log ""
            log "Settings may be changed here:"
            log ""
            log "    $SCRIPT_SETTINGS"
        fi
    fi

    log "\\n--------------------------------------------------------------------------------\\n"

    case "$OS" in
    "ubuntu1604")
        log "To garantee that all your changes take effect you should restart your system."
        ;;
    esac
}

function identifyOS {
    if [[ ! -f "/etc/os-release" ]]; then
        log "File /etc/os-release is missing"
        abort "Unable to identify operating system"
    fi

    # shellcheck source=/dev/null
    source "/etc/os-release"

    log "Operating system identified as ${PRETTY_NAME}"

    if [[ "$NAME" == "CentOS Linux" && "$VERSION_ID" == "7" ]]; then
        log "Warning: This OS is not officially supported by i-doit"
        abort "Warning: CentOS 7 is out-dated. Please consider to upgrade your OS."

        OS="centos7"
        APACHE_USER="apache"
        APACHE_GROUP="apache"
        APACHE_CONFIG_FILE="/etc/httpd/conf.d/i-doit.conf"
        MARIADB_CONFIG_FILE="/etc/my.cnf.d/99-i-doit.cnf"
        PHP_CONFIG_FILE="/etc/php.d/i-doit.ini"
        MARIADB_SOCKET="/var/lib/mysql/mysql.sock"
        PHP_FPM_SOCKET="/var/run/php-fpm/php-fpm.sock"
        APACHE_UNIT="httpd"
        MARIADB_UNIT="mariadb"
        MEMCACHED_UNIT="memcached"
        PHP_FPM_UNIT="php-fpm"
    elif [[ "$NAME" == "CentOS Linux" && "$VERSION_ID" == "8" ]]; then
        abort "Warning: This OS is not officially supported by i-doit"

        OS="centos8"
        APACHE_USER="apache"
        APACHE_GROUP="apache"
        APACHE_CONFIG_FILE="/etc/httpd/conf.d/i-doit.conf"
        MARIADB_CONFIG_FILE="/etc/my.cnf.d/99-i-doit.cnf"
        PHP_CONFIG_FILE="/etc/php.d/i-doit.ini"
        MARIADB_SOCKET="/var/lib/mysql/mysql.sock"
        PHP_FPM_SOCKET="/var/run/php-fpm/php-fpm.sock"
        APACHE_UNIT="httpd"
        MARIADB_UNIT="mariadb"
        MEMCACHED_UNIT="memcached"
        PHP_FPM_UNIT="php-fpm"
    elif [[ "$NAME" == "Debian GNU/Linux" && "$VERSION" == "12 (bookworm)" ]]; then
        export DEBIAN_FRONTEND="noninteractive"

        OS="debian12"
        APACHE_USER="www-data"
        APACHE_GROUP="www-data"
        APACHE_CONFIG_FILE="/etc/apache2/sites-available/i-doit.conf"
        MARIADB_CONFIG_FILE="/etc/mysql/mariadb.conf.d/99-i-doit.cnf"
        PHP_CONFIG_FILE="/etc/php/8.2/mods-available/i-doit.ini"
        MARIADB_SOCKET="/var/run/mysqld/mysqld.sock"
        PHP_FPM_SOCKET="/var/run/php/php8.2-fpm.sock"
        APACHE_UNIT="apache2"
        MARIADB_UNIT="mysql"
        MEMCACHED_UNIT="memcached"
        PHP_FPM_UNIT="php8.2-fpm"
    elif [[ "$NAME" == "Debian GNU/Linux" && "$VERSION" == "11 (bullseye)" ]]; then
        export DEBIAN_FRONTEND="noninteractive"
        abort "Error: Debian 11 is out-dated. It's not supported anymore. Please upgrade."
        OS="debian11"
        APACHE_USER="www-data"
        APACHE_GROUP="www-data"
        APACHE_CONFIG_FILE="/etc/apache2/sites-available/i-doit.conf"
        MARIADB_CONFIG_FILE="/etc/mysql/mariadb.conf.d/99-i-doit.cnf"
        PHP_CONFIG_FILE="/etc/php/7.4/mods-available/i-doit.ini"
        MARIADB_SOCKET="/var/run/mysqld/mysqld.sock"
        PHP_FPM_SOCKET="/var/run/php/php7.4-fpm.sock"
        APACHE_UNIT="apache2"
        MARIADB_UNIT="mysql"
        MEMCACHED_UNIT="memcached"
        PHP_FPM_UNIT="php7.4-fpm"
    elif [[ "$NAME" == "Debian GNU/Linux" && "$VERSION" == "10 (buster)" ]]; then
        abort "Error: This version of Debian GNU/Linux is not supported anymore. Please upgrade to Debian 12."
    elif [[ "$NAME" == "Debian GNU/Linux" && "$VERSION" == "9 (stretch)" ]]; then
        abort "Error: This version of Debian GNU/Linux is not supported anymore. Please upgrade to Debian 12."
    elif [[ "$NAME" == "Debian GNU/Linux" && "$VERSION" == "8 (jessie)" ]]; then
        abort "Error: This version of Debian GNU/Linux is not supported anymore. Please upgrade to Debian 12."
    elif [[ "$NAME" == "Red Hat Enterprise Linux" && "$VERSION_ID" == 8* ]]; then

        OS="rhel8"
        APACHE_USER="apache"
        APACHE_GROUP="apache"
        APACHE_CONFIG_FILE="/etc/httpd/conf.d/i-doit.conf"
        MARIADB_CONFIG_FILE="/etc/my.cnf.d/99-i-doit.cnf"
        PHP_CONFIG_FILE="/etc/php.d/i-doit.ini"
        MARIADB_SOCKET="/var/lib/mysql/mysql.sock"
        PHP_FPM_SOCKET="/var/run/php-fpm/php-fpm.sock"
        APACHE_UNIT="httpd"
        MARIADB_UNIT="mariadb"
        MEMCACHED_UNIT="memcached"
        PHP_FPM_UNIT="php-fpm"
    elif [[ "$NAME" == "Red Hat Enterprise Linux Server" && "$VERSION_ID" == 7* ]]; then
        abort "Warning: RHEL 7 is out-dated. Please consider to upgrade your OS."

        OS="rhel7"
        APACHE_USER="apache"
        APACHE_GROUP="apache"
        APACHE_CONFIG_FILE="/etc/httpd/conf.d/i-doit.conf"
        MARIADB_CONFIG_FILE="/etc/my.cnf.d/99-i-doit.cnf"
        PHP_CONFIG_FILE="/etc/php.d/i-doit.ini"
        MARIADB_SOCKET="/var/lib/mysql/mysql.sock"
        PHP_FPM_SOCKET="/var/run/php-fpm/php-fpm.sock"
        APACHE_UNIT="httpd"
        MARIADB_UNIT="mariadb"
        MEMCACHED_UNIT="memcached"
        PHP_FPM_UNIT="php-fpm"
    elif [[ "$NAME" == "SLES" && "$VERSION" == 15* ]]; then

        OS="sles15"
        INSTALL_DIR="/srv/www/htdocs"
        APACHE_USER="wwwrun"
        APACHE_GROUP="www"
        APACHE_CONFIG_FILE="/etc/apache2/vhosts.d/i-doit.conf"
        MARIADB_CONFIG_FILE="/etc/my.cnf.d/99-i-doit.cnf"
        PHP_CONFIG_FILE="/etc/php7/conf.d/i-doit.ini"
        MARIADB_SOCKET="/var/run/mysql/mysql.sock"
        PHP_FPM_SOCKET="/var/run/php-fpm.sock"
        APACHE_UNIT="apache2"
        MARIADB_UNIT="mariadb"
        MEMCACHED_UNIT="memcached"
        PHP_FPM_UNIT="php-fpm"
    elif [[ "$NAME" = "SLES" && "$VERSION_ID" == 12* ]]; then
        abort "Error: SLES 12 is out-dated. It's not supported anymore. Please upgrade."
    elif [[ "$NAME" == "openSUSE Leap" && "$VERSION" == 15* ]]; then

        OS="opensuse15"
        INSTALL_DIR="/srv/www/htdocs"
        APACHE_USER="wwwrun"
        APACHE_GROUP="www"
        APACHE_CONFIG_FILE="/etc/apache2/vhosts.d/i-doit.conf"
        MARIADB_CONFIG_FILE="/etc/my.cnf.d/99-i-doit.cnf"
        PHP_CONFIG_FILE="/etc/php7/conf.d/i-doit.ini"
        MARIADB_SOCKET="/var/run/mysql/mysql.sock"
        PHP_FPM_SOCKET="/var/run/php-fpm.sock"
        APACHE_UNIT="apache2"
        MARIADB_UNIT="mariadb"
        MEMCACHED_UNIT="memcached"
        PHP_FPM_UNIT="php-fpm"
    elif [[ "$NAME" = "openSUSE" && "$VERSION_ID" == 12* ]]; then
        abort "Error: openSUSE 12 is out-dated. It's not supported anymore. Please upgrade."
    elif [[ "$NAME" == "Ubuntu" && "$VERSION_ID" == "24.04" ]]; then
        export DEBIAN_FRONTEND="noninteractive"
        OS="ubuntu2404"
        APACHE_USER="www-data"
        APACHE_GROUP="www-data"
        APACHE_CONFIG_FILE="/etc/apache2/sites-available/i-doit.conf"
        MARIADB_CONFIG_FILE="/etc/mysql/mariadb.conf.d/99-i-doit.cnf"
        PHP_CONFIG_FILE="/etc/php/8.3/mods-available/i-doit.ini"
        MARIADB_SOCKET="/var/run/mysqld/mysqld.sock"
        PHP_FPM_SOCKET="/var/run/php/php8.3-fpm.sock"
        APACHE_UNIT="apache2"
        MARIADB_UNIT="mysql"
        MEMCACHED_UNIT="memcached"
        PHP_FPM_UNIT="php8.3-fpm"
    elif [[ "$NAME" == "Ubuntu" && "$VERSION_ID" == "22.04" ]]; then
        export DEBIAN_FRONTEND="noninteractive"

        OS="ubuntu2204"
        APACHE_USER="www-data"
        APACHE_GROUP="www-data"
        APACHE_CONFIG_FILE="/etc/apache2/sites-available/i-doit.conf"
        MARIADB_CONFIG_FILE="/etc/mysql/mariadb.conf.d/99-i-doit.cnf"
        PHP_CONFIG_FILE="/etc/php/8.1/mods-available/i-doit.ini"
        MARIADB_SOCKET="/var/run/mysqld/mysqld.sock"
        PHP_FPM_SOCKET="/var/run/php/php8.1-fpm.sock"
        APACHE_UNIT="apache2"
        MARIADB_UNIT="mysql"
        MEMCACHED_UNIT="memcached"
        PHP_FPM_UNIT="php8.1-fpm"
    elif [[ "$NAME" == "Ubuntu" && "$VERSION_ID" == "20.04" ]]; then
        export DEBIAN_FRONTEND="noninteractive"
        abort "Error: Ubuntu 20.04 is out-dated. It's not supported anymore. Please upgrade."
        OS="ubuntu2004"
        APACHE_USER="www-data"
        APACHE_GROUP="www-data"
        APACHE_CONFIG_FILE="/etc/apache2/sites-available/i-doit.conf"
        MARIADB_CONFIG_FILE="/etc/mysql/mariadb.conf.d/99-i-doit.cnf"
        PHP_CONFIG_FILE="/etc/php/7.4/mods-available/i-doit.ini"
        MARIADB_SOCKET="/var/run/mysqld/mysqld.sock"
        PHP_FPM_SOCKET="/var/run/php/php7.4-fpm.sock"
        APACHE_UNIT="apache2"
        MARIADB_UNIT="mysql"
        MEMCACHED_UNIT="memcached"
        PHP_FPM_UNIT="php7.4-fpm"
    elif [[ "$NAME" == "Ubuntu" && "$VERSION_ID" == "18.04" ]]; then
        abort "Error: Ubuntu 18.04 is out-dated. It's not supported anymore. Please upgrade."
    elif [[ "$NAME" == "Ubuntu" && "$VERSION_ID" == "16.04" ]]; then
        abort "Error: Ubuntu 16.04 is out-dated. It's not supported anymore. Please upgrade."
    else
        abort "Operating system ${PRETTY_NAME} is not supported"
    fi
}

function checkHardwareRequirements {
    local cores=0
    local ram=0
    local arch=""

    log "Check hardware requirements…"

    arch=$(uname -m)

    if [[ "$arch" != "x86_64" ]]; then
        log "Attention! The system architecture is not x86 64 bit, but ${arch}. This could cause unwanted behaviour."

        askNoYes "Do you really want to continue?" || cancel
    fi

    cores=$(nproc)

    if [[ "$cores" -ge "$MIN_CPU_CORES" ]]; then
        log "$cores CPU cores detected; $MIN_CPU_CORES is required minimum"
    else
        log "Less than $MIN_CPU_CORES CPU cores detected"
        log "Found only $cores CPU core(s)."
        log "Your system does not meet the requirements. See:"
        log ""
        log "    <https://kb.i-doit.com/display/en/System+Requirements>"
        log ""
        askNoYes "Do you really want to continue?" || cancel
    fi

    ram=$(vmstat --stats --unit b | grep -i "total memory" | awk '{print $1}')

    if [[ "$ram" -ge "$MIN_RAM" ]]; then
        log "$ram bytes of total memory detected; $MIN_RAM is required minimum"
    else
        log "Less than $MIN_RAM bytes of total memory detected"
        log "Found only $ram bytes."
        log "Your system does not meet the requirements. See:"
        log ""
        log "    <https://kb.i-doit.com/display/en/System+Requirements>"
        log ""
        askNoYes "Do you really want to continue?" || cancel
    fi
}

function checkSoftwareRequirements {
    local failed=0

    log "Check for installed applications and services…"

    MARIADB_BIN=$(command -v mysql)
    SUDO_BIN=$(command -v sudo)
    UNZIP_BIN=$(command -v unzip)
    WGET_BIN=$(command -v wget)
    PHP_BIN=$(command -v php)

    declare -A binaries
    binaries["mariabdb"]="$MARIADB_BIN"
    binaries["sudo"]="$SUDO_BIN"
    binaries["unzip"]="$UNZIP_BIN"
    binaries["wget"]="$WGET_BIN"
    binaries["php"]="$PHP_BIN"
    binaries["systemctl"]=$(command -v systemctl)
    binaries["chronic"]=$(command -v chronic)
    binaries["memcached"]=$(command -v memcached)

    case "$OS" in
    "rhel7" | "rhel8" | "centos7" | "centos8")
        binaries["httpd"]=$(command -v httpd)
        ;;
    *)
        binaries["apachectl"]=$(command -v apachectl)
        ;;
    esac

    for bin in "${!binaries[@]}"; do
        if [[ -x "${binaries[$bin]}" ]]; then
            log "$bin: found"
        else
            log "$bin: missing"
            ((failed++))
        fi
    done

    if [[ -x "$PHP_BIN" ]]; then
        log "Check for installed PHP extensions…"

        case "$OS" in
        ## TODO There is no php-memcached on RHEL 8:
        "rhel8" | "centos8")
            local phpExtensions=(bcmath ctype curl fileinfo gd json ldap
                mbstring mysqli mysqlnd pgsql session soap xml zip)
            ;;
        *)
            local phpExtensions=(bcmath ctype curl fileinfo gd json ldap
                mbstring memcached mysqli mysqlnd pgsql session soap xml zip)
            ;;
        esac

        for phpExtension in "${phpExtensions[@]}"; do
            if "$PHP_BIN" -m | grep "$phpExtension" >/dev/null; then
                log "PHP extension $phpExtension: found"
            else
                log "PHP extension $phpExtension: missing"
                ((failed++))
            fi
        done
    fi

    case "$failed" in
    0)
        log "All software requirements met. Excellent."
        ;;
    1)
        abort "Important software requirement is missing. Please install and configure it."
        ;;
    *)
        abort "Important software requirements are missing. Please install and configure them."
        ;;
    esac
}

function configureOS {
    case "$OS" in
    "debian12")
        configureDebian12
        ;;
    "debian11")
        configureDebian11
        ;;
    "ubuntu2404")
        configureUbuntu2404
        ;;
    "ubuntu2204")
        configureUbuntu2204
        ;;
    "ubuntu2004")
        configureUbuntu2004
        ;;
    "rhel7")
        configureRHEL7
        ;;
    "rhel8")
        configureRHEL8
        ;;
    "centos7")
        configureCentOS7
        ;;
    "centos8")
        configureCentOS8
        ;;
    "sles15")
        configureSLES15
        ;;
    "opensuse15")
        configureOpenSuse15
        ;;
    *)
        abort "Unkown operating system '${OS}'!?!"
        ;;
    esac
}
function configureDebian12 {
    log "Keep your Debian packages up-to-date"
    apt-get -qq --yes update || abort "Unable to update Debian package repositories"
    apt-get -qq --yes full-upgrade || abort "Unable to perform update of Debian packages"
    apt-get -qq --yes clean || abort "Unable to cleanup Debian packages"
    apt-get -qq --yes autoremove || abort "Unable to remove unnecessary Debian packages"

    log "Install required Debian 12 packages"
    apt-get -qq --yes install --no-install-recommends \
        apache2 libapache2-mod-fcgid \
        mariadb-client mariadb-server \
        php-bcmath php-cli php-common php-curl php-fpm php-gd \
        php-ldap php-mbstring php-mysql php-opcache php-pgsql \
        php-soap php-xml php-zip \
        php-memcached \
        memcached unzip sudo moreutils || abort "Unable to install required Debian packages"
}

function configureDebian11 {
    log "Keep your Debian packages up-to-date"
    apt-get -qq --yes update || abort "Unable to update Debian package repositories"
    apt-get -qq --yes full-upgrade || abort "Unable to perform update of Debian packages"
    apt-get -qq --yes clean || abort "Unable to cleanup Debian packages"
    apt-get -qq --yes autoremove || abort "Unable to remove unnecessary Debian packages"

    log "Install required Debian packages"
    apt-get -qq --yes install --no-install-recommends \
        apache2 libapache2-mod-fcgid \
        mariadb-client mariadb-server \
        php7.4-bcmath php7.4-cli php7.4-common php7.4-curl php7.4-fpm php7.4-gd php7.4-json \
        php7.4-ldap php7.4-mbstring php7.4-mysql php7.4-opcache php7.4-pgsql \
        php7.4-soap php7.4-xml php7.4-zip \
        php-memcached \
        memcached unzip sudo moreutils || abort "Unable to install required Debian packages"
}

function configureUbuntu2004 {
    log "Keep your Ubuntu packages up-to-date"
    apt-get -qq --yes update || abort "Unable to update Ubuntu package repositories"
    apt-get -qq --yes full-upgrade || abort "Unable to perform update of Ubuntu packages"
    apt-get -qq --yes clean || abort "Unable to cleanup Ubuntu packages"
    apt-get -qq --yes autoremove || abort "Unable to remove unnecessary Ubuntu packages"

    log "Install required Ubuntu packages"
    apt-get -qq --yes install --no-install-recommends \
        apache2 libapache2-mod-fcgid \
        mariadb-client mariadb-server \
        php7.4-bcmath php7.4-cli php7.4-common php7.4-curl php7.4-fpm php7.4-gd php7.4-json \
        php7.4-ldap php7.4-mbstring php7.4-mysql php7.4-opcache php7.4-pgsql \
        php7.4-soap php7.4-xml php7.4-zip \
        php-memcached \
        memcached unzip moreutils || abort "Unable to install required Ubuntu packages"
}

function configureUbuntu2204 {
    log "Keep your Ubuntu packages up-to-date"
    apt-get -qq --yes update || abort "Unable to update Ubuntu package repositories"
    apt-get -qq --yes full-upgrade || abort "Unable to perform update of Ubuntu packages"
    apt-get -qq --yes clean || abort "Unable to cleanup Ubuntu packages"
    apt-get -qq --yes autoremove || abort "Unable to remove unnecessary Ubuntu packages"

    log "Install required Ubuntu packages"
    apt-get -qq --yes install --no-install-recommends \
        apache2 libapache2-mod-fcgid \
        mariadb-client mariadb-server \
        php8.1-bcmath php8.1-cli php8.1-common php8.1-curl php8.1-fpm php8.1-gd \
        php8.1-ldap php8.1-mbstring php8.1-mysql php8.1-opcache php8.1-pgsql \
        php8.1-soap php8.1-xml php8.1-zip \
        php-memcached \
        memcached unzip moreutils || abort "Unable to install required Ubuntu packages"
}

function configureUbuntu2404 {
    log "Keep your Ubuntu packages up-to-date"
    apt-get -qq --yes update || abort "Unable to update Ubuntu package repositories"
    apt-get -qq --yes full-upgrade || abort "Unable to perform update of Ubuntu packages"
    apt-get -qq --yes clean || abort "Unable to cleanup Ubuntu packages"
    apt-get -qq --yes autoremove || abort "Unable to remove unnecessary Ubuntu packages"

    log "Install required Ubuntu packages"
    apt-get -qq --yes install --no-install-recommends \
        apache2 libapache2-mod-fcgid \
        mariadb-client mariadb-server \
        php8.3-bcmath php8.3-cli php8.3-common php8.3-curl php8.3-fpm php8.3-gd \
        php8.3-ldap php8.3-mbstring php8.3-mysql php8.3-opcache php8.3-pgsql \
        php8.3-soap php8.3-xml php8.3-zip \
        php-memcached \
        memcached unzip moreutils || abort "Unable to install required Ubuntu packages"
}

function configureCentOS7 {
    log "Keep your yum packages up-to-date"
    yum --assumeyes --quiet update || abort "Unable to update yum packages"
    yum --assumeyes --quiet autoremove || abort "Unable to remove out-dated yum packages"
    yum --assumeyes --quiet clean all || abort "Unable to clean yum caches"
    rm -rf /var/cache/yum || abort "Unable to remove orphaned yum caches"

    log "Install some important packages, for example Apache Web server"
    yum --assumeyes --quiet install httpd memcached unzip wget zip || abort "Unable to install packages"

    log "RHEL 7 has out-dated packages for PHP and MariaDB."
    log "This script will fix this issue by enabling these 3rd party repositories:"
    log ""
    log "    Webtatic.com for PHP 7.2"
    log "    Official MariaDB repository for MariaDB 10.3"
    log ""

    if askYesNo "Do you agree with it?"; then
        if ! rpm -qa | grep "epel-release" >/dev/null; then
            log "Import EPEL public GPG key"
            rpm --import --quiet https://dl.fedoraproject.org/pub/epel/RPM-GPG-KEY-EPEL-7 || abort "Unable to import public GPG key from EPEL"
            log "Add EPEL releases"
            rpm -Uvh --quiet https://dl.fedoraproject.org/pub/epel/epel-release-latest-7.noarch.rpm || abort "Unable to install epel-releases via yum"
        fi

        if ! rpm -qa | grep "webtatic-release" >/dev/null; then
            log "Import W            ebtatic public GPG key"
            rpm --import --quiet https://mirror.webtatic.com/yum/RPM-GPG-KEY-webtatic-el7 || abort "Unable to import GPG key from Webtatic"
            log "Add Webtatic releases"
            rpm -Uvh --quiet https://mirror.webtatic.com/yum/el7/webtatic-release.rpm || abort "Unable to add Webtatic"
        fi

        log "Install PHP packages"
        yum --assumeyes --quiet install \
            php72w-bcmath php72w-cli php72w-common php72w-fpm php72w-gd php72w-ldap \
            php72w-mbstring php72w-mysqlnd php72w-opcache php72w-pdo \
            php72w-pecl-memcached php72w-pgsql php72w-soap php72w-xml || abort "Unable to install PHP packages"

        log "Enable MariaDB repository"
        cat <<EOF >/etc/yum.repos.d/MariaDB.repo || abort "Unable to create and edit file '/etc/yum.repos.d/MariaDB.repo'"
# MariaDB 10.3 repository list
# http://downloads.mariadb.org/mariadb/repositories/
[mariadb]
name = MariaDB
baseurl = http://yum.mariadb.org/10.3/centos7-amd64
gpgkey=https://yum.mariadb.org/RPM-GPG-KEY-MariaDB
gpgcheck=1
EOF

        log "Install MariaDB packages"
        rpm --import --quiet https://yum.mariadb.org/RPM-GPG-KEY-MariaDB || abort "Unable to import GPG key from MariaDB"
        ## Suppress unnecessary notices which could confuse the user:
        yum --assumeyes --quiet install MariaDB-server MariaDB-client &>/dev/null || abort "Unable to install MariaDB"
    fi

    log "Install 'moreutils'"
    yum --assumeyes --quiet install moreutils || abort "Unable to install packages"

    for unit in $APACHE_UNIT $MARIADB_UNIT $MEMCACHED_UNIT $PHP_FPM_UNIT; do
        unitctl "enable" "$unit"
        unitctl "start" "$unit"
    done

    log "Allow incoming HTTP traffic"
    systemctl -q is-active firewalld.service || (
        log "Firewall is inactive."
        unitctl "start" "firewalld"
    )
    firewall-cmd --permanent --add-service=http || abort "Unable to configure firewall"
    unitctl "restart" "firewalld"
}

function configureCentOS8 {
    log "Keep your yum packages up-to-date"
    yum --assumeyes --quiet update || abort "Unable to update yum packages"
    yum --assumeyes --quiet autoremove || abort "Unable to remove out-dated yum packages"
    yum --assumeyes --quiet clean all || abort "Unable to clean yum caches"
    rm -rf /var/cache/yum || abort "Unable to remove orphaned yum caches"

    for appStream in httpd:2.4 mariadb:10.3 php:7.4; do
        log "Install AppStream $appStream"
        yum --assumeyes --quiet module install "$appStream"
    done

    log "Install some important packages"
    yum --assumeyes --quiet install \
        memcached unzip wget zip \
        php-bcmath php-gd php-ldap php-mysqli php-mysqlnd \
        php-pgsql php-soap php-zip || abort "Unable to install packages"

    if ! rpm -qa | grep "epel-release" >/dev/null; then
        log "Import EPEL public GPG key"
        rpm --import --quiet https://dl.fedoraproject.org/pub/epel/RPM-GPG-KEY-EPEL-8 || abort "Unable to import public GPG key from EPEL"
        log "Add epel releases repository"
        rpm -Uvh --quiet https://dl.fedoraproject.org/pub/epel/epel-release-latest-8.noarch.rpm || abort "Unable to install epel releases repository"
    fi

    log "Enable PowerTools for CentOS 8"
    dnf --assumeyes --quiet config-manager --set-enabled powertools || abort "Unable to enable PowerTools"

    log "Install moreutils with all dependencies"
    dnf --assumeyes --quiet install moreutils || abort "Unable to install moreutils"

    for unit in $APACHE_UNIT $MARIADB_UNIT $MEMCACHED_UNIT $PHP_FPM_UNIT; do
        unitctl "enable" "$unit"
        unitctl "start" "$unit"
    done

    log "Allow incoming HTTP traffic"
    systemctl -q is-active firewalld.service || (
        log "Firewall is inactive."
        unitctl "start" "firewalld"
    )
    firewall-cmd --permanent --add-service=http || abort "Unable to configure firewall"
    unitctl "restart" "firewalld"
}

function configureRHEL8 {
    log "Keep your yum packages up-to-date"
    yum --assumeyes --quiet update || abort "Unable to update yum packages"
    yum --assumeyes --quiet autoremove || abort "Unable to remove out-dated yum packages"
    yum --assumeyes --quiet clean all || abort "Unable to clean yum caches"
    rm -rf /var/cache/yum || abort "Unable to remove orphaned yum caches"

    for appStream in httpd:2.4 mariadb:10.3 php:7.4; do
        log "Install AppStream $appStream"
        yum --assumeyes --quiet module install "$appStream"
    done

    log "Install some important packages"
    yum --assumeyes --quiet install \
        memcached unzip wget zip \
        php-bcmath php-gd php-ldap php-mysqli php-mysqlnd \
        php-pgsql php-soap php-zip || abort "Unable to install packages"

    if ! rpm -qa | grep "epel-release" >/dev/null; then
        log "Import EPEL public GPG key"
        rpm --import --quiet https://dl.fedoraproject.org/pub/epel/RPM-GPG-KEY-EPEL-8 || abort "Unable to import public GPG key from EPEL"
        log "Add epel releases repository"
        rpm -Uvh --quiet https://dl.fedoraproject.org/pub/epel/epel-release-latest-8.noarch.rpm || abort "Unable to install epel releases repository"
    fi

    log "Enable codeready-builder for RHEL 8"
    subscription-manager repos --enable "codeready-builder-for-rhel-8-x86_64-rpms" || abort "Unable to enable Codeready-Builder"

    log "Install moreutils with all dependencies"
    dnf --assumeyes --quiet install moreutils || abort "Unable to install moreutils"

    for unit in $APACHE_UNIT $MARIADB_UNIT $MEMCACHED_UNIT $PHP_FPM_UNIT; do
        unitctl "enable" "$unit"
        unitctl "start" "$unit"
    done

    log "Allow incoming HTTP traffic"
    systemctl -q is-active firewalld.service || (
        log "Firewall is inactive."
        unitctl "start" "firewalld"
    )
    firewall-cmd --permanent --add-service=http || abort "Unable to configure firewall"
    unitctl "restart" "firewalld"
}

function configureRHEL7 {
    log "Keep your yum packages up-to-date"
    yum --assumeyes --quiet update || abort "Unable to update yum packages"
    yum --assumeyes --quiet autoremove || abort "Unable to remove out-dated yum packages"
    yum --assumeyes --quiet clean all || abort "Unable to clean yum caches"
    rm -rf /var/cache/yum || abort "Unable to remove orphaned yum caches"

    log "Install some important packages, for example Apache Web server"
    yum --assumeyes --quiet install httpd memcached unzip wget zip || abort "Unable to install packages"

    log "RHEL 7 has out-dated packages for PHP and MariaDB."
    log "This script will fix this issue by enabling these 3rd party repositories:"
    log ""
    log "    Webtatic.com for PHP 7.2"
    log "    Official MariaDB repository for MariaDB 10.3"
    log ""

    if askYesNo "Do you agree with it?"; then
        if ! rpm -qa | grep "epel-release" >/dev/null; then
            log "Import EPEL public GPG key"
            rpm --import --quiet https://dl.fedoraproject.org/pub/epel/RPM-GPG-KEY-EPEL-7 || abort "Unable to import public GPG key from EPEL"
            log "Add EPEL releases"
            rpm -Uvh --quiet https://dl.fedoraproject.org/pub/epel/epel-release-latest-7.noarch.rpm || abort "Unable to install epel-releases via yum"
        fi

        if ! rpm -qa | grep "webtatic-release" >/dev/null; then
            log "Import Webtatic public GPG key"
            rpm --import --quiet https://mirror.webtatic.com/yum/RPM-GPG-KEY-webtatic-el7 || abort "Unable to import GPG key from Webtatic"
            log "Add Webtatic releases"
            rpm -Uvh --quiet https://mirror.webtatic.com/yum/el7/webtatic-release.rpm || abort "Unable to add Webtatic"
        fi

        log "Install PHP packages"
        yum --assumeyes --quiet install \
            php72w-bcmath php72w-cli php72w-common php72w-fpm php72w-gd php72w-ldap \
            php72w-mbstring php72w-mysqlnd php72w-opcache php72w-pdo \
            php72w-pecl-memcached php72w-pgsql php72w-soap php72w-xml || abort "Unable to install PHP packages"

        log "Enable MariaDB repository"
        cat <<EOF >/etc/yum.repos.d/MariaDB.repo || abort "Unable to create and edit file '/etc/yum.repos.d/MariaDB.repo'"
# MariaDB 10.3 RedHat repository list
# http://downloads.mariadb.org/mariadb/repositories/
[mariadb]
name = MariaDB
baseurl = http://yum.mariadb.org/10.3/rhel7-amd64
gpgkey=https://yum.mariadb.org/RPM-GPG-KEY-MariaDB
gpgcheck=1
EOF

        log "Install MariaDB packages"
        rpm --import --quiet https://yum.mariadb.org/RPM-GPG-KEY-MariaDB || abort "Unable to import GPG key from MariaDB"
        ## Suppress unnecessary notices which could confuse the user:
        yum --assumeyes --quiet install MariaDB-server MariaDB-client &>/dev/null || abort "Unable to install MariaDB"
    fi

    log "Enable required repository 'rhel-7-server-eus-optional-rpms'"
    subscription-manager repos --enable=rhel-7-server-eus-optional-rpms || abort "Repository cannot be enabled"
    ## Install moreutils *after* EPEL *and* rhel-7-server-eus-optional-rpms have been
    ## enabled!

    log "Install 'moreutils'"
    yum --assumeyes --quiet install moreutils || abort "Unable to install packages"

    for unit in $APACHE_UNIT $MARIADB_UNIT $MEMCACHED_UNIT $PHP_FPM_UNIT; do
        unitctl "enable" "$unit"
        unitctl "start" "$unit"
    done

    log "Allow incoming HTTP traffic"
    systemctl -q is-active firewalld.service || (
        log "Firewall is inactive."
        unitctl "start" "firewalld"
    )
    firewall-cmd --permanent --add-service=http || abort "Unable to configure firewall"
    unitctl "restart" "firewalld"
}

function configureSLES15 {
    local web_repos=""
    local openSuseRepo=""
    local webScriptingModuleAlias="Web_and_Scripting_Module_${VERSION_ID}_x86_64"
    local webScriptingModuleProduct="sle-module-web-scripting/${VERSION_ID}/x86_64"

    log "Keep your packages up-to-date"
    zypper --quiet --non-interactive refresh || abort "Unable to refresh software repositories"
    zypper --quiet --non-interactive update || abort "Unable to update software packages"

    web_repos=$(zypper repos -E | grep -c "$webScriptingModuleAlias")

    if [[ "$web_repos" -lt 2 ]]; then
        log "The following module is required:"
        log ""
        log "    Web and Scripting"
        log ""
        log "This script will activate it."

        if askYesNo "Do you agree with it?"; then
            SUSEConnect -p "$webScriptingModuleProduct" || abort "Unable to active module"
        else
            abort "Essential software repositories are missing"
        fi
    fi

    log "Install software packages"
    zypper --quiet --non-interactive install --no-recommends \
        apache2 \
        mariadb mariadb-client \
        memcached \
        make sudo unzip \
        php7 php7-bcmath php7-bz2 php7-ctype php7-curl php7-fpm php7-gd php7-gettext php7-fileinfo \
        php7-json php7-ldap php7-mbstring php7-mysql php7-opcache php7-openssl php7-pdo php7-pgsql \
        php7-phar php7-posix php7-soap php7-sockets php7-sqlite php7-xsl php7-zip php7-zlib || abort "Unable to install required software packages"

    openSuseRepo=$(zypper repos -E | grep -c "server_php_extensions_php7")

    if [[ "$openSuseRepo" -lt 1 ]]; then
        log "i-doit requires PHP module for memcached"
        log "But this PHP module is not available in SLE standard repositories"
        log "It will be installed from a 3rd-party repository from openSUSE:"
        log ""
        log "    server:php:extensions:php7"
        log ""
        log "Details:"
        log ""
        log "    https://software.opensuse.org/download.html?project=server%3Aphp%3Aextensions%3Aphp7&package=php7-memcached"

        if [[ "$VERSION_ID" == 15 ]]; then
            zypper --quiet --non-interactive addrepo \
                --gpgcheck --refresh \
                https://download.opensuse.org/repositories/server:php:extensions:php7/SLE_15/server:php:extensions:php7.repo || abort "Unable to add repository"
            zypper --quiet --non-interactive --gpg-auto-import-keys refresh || abort "Unable to refresh software repositories"

        elif [[ "$VERSION_ID" == 15.1 ]]; then
            zypper --quiet --non-interactive addrepo \
                --gpgcheck --refresh \
                https://download.opensuse.org/repositories/server:/php:/extensions/SLE_15_SP1/server:php:extensions.repo || abort "Unable to add repository"
            zypper --quiet --non-interactive --gpg-auto-import-keys refresh || abort "Unable to refresh software repositories"

        elif [[ "$VERSION_ID" == 15.2 ]]; then
            zypper --quiet --non-interactive addrepo \
                --gpgcheck --refresh \
                https://download.opensuse.org/repositories/server:/php:/extensions/SLE_15_SP2/server:php:extensions.repo || abort "Unable to add repository"
            zypper --quiet --non-interactive --gpg-auto-import-keys refresh || abort "Unable to refresh software repositories"
        fi
    fi

    zypper --quiet --non-interactive install --no-recommends php7-memcached || abort "Unable to install required software package"

    zypper --quiet --non-interactive clean || abort "Unable to clean up cached software packages"

    for unit in $APACHE_UNIT $MARIADB_UNIT $MEMCACHED_UNIT; do
        unitctl "enable" "$unit"
        unitctl "start" "$unit"
    done

    log "Allow incoming HTTP traffic"
    systemctl -q is-active firewalld.service || (
        log "Firewall is inactive."
        unitctl "start" "firewalld"
    )
    firewall-cmd --permanent --add-service=http || abort "Unable to configure firewall"
    unitctl "restart" "firewalld"

    if [[ ! -x "$(command -v chronic)" ]]; then
        log "Install 'chronic'"
        ## TODO: I know, this seems to be pretty ugly, but:
        ## Why the hack is moreutils not included in the standard repositories?!?
        wget --quiet -O "${TMP_DIR}/chronic" \
            https://git.joeyh.name/index.cgi/moreutils.git/plain/chronic || abort "Unable to download 'chronic'"
        chmod +x "${TMP_DIR}/chronic" || abort "Unable to set executable bit"
        mv "${TMP_DIR}/chronic" /usr/bin || abort "Unable to move 'chronic' to '/usr/bin'"
        wget --quiet -O - https://cpanmin.us | perl - App::cpanminus || abort "Unable to install cpanminus"
        cpanm --quiet --notest --install IPC::Run || abort "Unable to install Perl module IPC::Run"
    fi
}

function configureOpenSuse15 {
    local web_repos=""
    local openSuseRepo=""

    log "Keep your packages up-to-date"
    zypper --quiet --non-interactive refresh || abort "Unable to refresh software repositories"
    zypper --quiet --non-interactive update || abort "Unable to update software packages"

    log "Install software packages"
    zypper --quiet --non-interactive install --no-recommends \
        apache2 \
        mariadb mariadb-client \
        memcached \
        make sudo unzip \
        php7 php7-bcmath php7-bz2 php7-ctype php7-curl php7-fpm php7-gd php7-gettext php7-fileinfo \
        php7-json php7-ldap php7-mbstring php7-mysql php7-memcached php7-opcache php7-openssl php7-pdo \
        php7-pgsql php7-phar php7-posix php7-soap php7-sockets php7-sqlite php7-xsl php7-zip php7-zlib || abort "Unable to install required software packages"

    zypper --quiet --non-interactive clean || abort "Unable to clean up cached software packages"

    for unit in $APACHE_UNIT $MARIADB_UNIT $MEMCACHED_UNIT; do
        unitctl "enable" "$unit"
        unitctl "start" "$unit"
    done

    log "Allow incoming HTTP traffic"
    systemctl -q is-active firewalld.service || (
        log "Firewall is inactive."
        unitctl "start" "firewalld"
    )
    firewall-cmd --permanent --add-service=http || abort "Unable to configure firewall"
    unitctl "restart" "firewalld"

    if [[ ! -x "$(command -v chronic)" ]]; then
        log "Install 'chronic'"
        ## TODO: I know, this seems to be pretty ugly, but:
        ## Why the hack is moreutils not included in the standard repositories?!?
        wget --quiet -O "${TMP_DIR}/chronic" \
            https://git.joeyh.name/index.cgi/moreutils.git/plain/chronic || abort "Unable to download 'chronic'"
        chmod +x "${TMP_DIR}/chronic" || abort "Unable to set executable bit"
        mv "${TMP_DIR}/chronic" /usr/bin || abort "Unable to move 'chronic' to '/usr/bin'"
        wget --quiet -O - https://cpanmin.us | perl - App::cpanminus || abort "Unable to install cpanminus"
        cpanm --quiet --notest --install IPC::Run || abort "Unable to install Perl module IPC::Run"
    fi
}

function configureProxy {
    if [[ -n "${https_proxy+x}" ]]; then
        log "Found proxy settings in environment variable 'https_proxy': $https_proxy"

        askYesNo "Do you want to use this setting?" && return 0
    fi

    echo -n -e "Provide proxy settings [schema: https://username:password@proxy:port]: "

    read -r answer

    if [[ -n "$answer" ]]; then
        log "Set environment variable 'https_proxy' to '${answer}'"
        export https_proxy="$answer"
    else
        log "No settings found. Skip it."
    fi
}

function configurePHP {
    local php_en_mod=""
    local php_version=""

    log "Configure PHP"

    php_version=$(php --version | head -n1 -c7 | tail -c3)

    case "$php_version" in
    "5.4" | "5.5" | "5.6" | "7.0" | "7.1" | "7.2" | "7.3")
        abort "PHP ${php_version} is way too old. Please upgrade. We recommend version ${RECOMMENDED_PHP_VERSION}."
        ;;
    "7.4")
        log "PHP ${php_version} is installed, but this version is deprecated. Please consider to upgrade. We recommend version ${RECOMMENDED_PHP_VERSION}."
        php_en_mod=$(command -v phpenmod)
        ;;
    "8.0")
        php_en_mod=$(command -v phpenmod)
        ;;
    "8.1")
        php_en_mod=$(command -v phpenmod)
        ;;
    "8.2")
        php_en_mod=$(command -v phpenmod)
        ;;
    "8.3")
        php_en_mod=$(command -v phpenmod)
        ;;
    *)
        abort "PHP ${php_version} is not supported. Please follow the system requirements. We recommend version ${RECOMMENDED_PHP_VERSION}."
        ;;
    esac

    log "Write PHP settings to '${PHP_CONFIG_FILE}'"
    cat <<EOF >"$PHP_CONFIG_FILE" || abort "Unable to create and edit file '${PHP_CONFIG_FILE}'"

allow_url_fopen = Yes
file_uploads = On
magic_quotes_gpc = Off
max_execution_time = 300
max_file_uploads = 42
max_input_time = 60
max_input_vars = 10000
memory_limit = 256M
post_max_size = 128M
register_argc_argv = On
register_globals = Off
short_open_tag = On
upload_max_filesize = 128M
display_errors = Off
display_startup_errors = Off
error_reporting = E_ALL & ~E_DEPRECATED & ~E_STRICT
log_errors = On
default_charset = "UTF-8"
default_socket_timeout = 60
date.timezone = Europe/Berlin
session.gc_maxlifetime = 604800
session.cookie_lifetime = 0
mysqli.default_socket = ${MARIADB_SOCKET}
EOF

    ## SLES has no phpenmod:
    if [[ -n "$php_en_mod" ]]; then
        log "Enable PHP settings"
        "$php_en_mod" i-doit
        log "Enable PHP module for memcached"
        "$php_en_mod" memcached
    fi
}

function configurePHPFPM {
    log "Configure PHP-FPM"

    case "$OS" in
    "debian11" | "debian12" | "ubuntu2004" | "ubuntu2204" | "ubuntu2404")
        unitctl "restart" "$PHP_FPM_UNIT"
        ;;
    "rhel7" | "rhel8" | "centos7" | "centos8")
        log "Disable default configuration file"
        mv /etc/php-fpm.d/www.conf{,.bak} || abort "Unable to disable default configuration file"
        log "Put new settings into file '/etc/php-fpm.d/i-doit.conf'"
        cat <<EOF >/etc/php-fpm.d/i-doit.conf || abort "Unable to create and edit file '/etc/php-fpm.d/i-doit.conf'"
[i-doit]
listen = ${PHP_FPM_SOCKET}
user = ${APACHE_USER}
group = ${APACHE_GROUP}
listen.owner = ${APACHE_USER}
listen.group = ${APACHE_GROUP}
pm = dynamic
pm.max_children = 50
pm.start_servers = 5
pm.min_spare_servers = 5
pm.max_spare_servers = 35
security.limit_extensions = .php
EOF

        unitctl "restart" "$PHP_FPM_UNIT"
        ;;
    "sles15" | "opensuse15")
        log "Enable PHP FPM configuration files"
        mv /etc/php7/fpm/php-fpm.conf{.default,} || abort "Unable to move file"
        log "Put new settings into file '/etc/php7/fpm/php-fpm.d/i-doit.conf'"
        cat <<EOF >/etc/php7/fpm/php-fpm.d/i-doit.conf || abort "Unable to create and edit file '/etc/php7/fpm/php-fpm.d/i-doit.conf'"
[i-doit]
listen = ${PHP_FPM_SOCKET}
user = ${APACHE_USER}
group = ${APACHE_GROUP}
listen.owner = ${APACHE_USER}
listen.group = ${APACHE_GROUP}
pm = dynamic
pm.max_children = 5
pm.start_servers = 2
pm.min_spare_servers = 1
pm.max_spare_servers = 3
security.limit_extensions = .php
EOF

        unitctl "enable" "$PHP_FPM_UNIT"
        unitctl "start" "$PHP_FPM_UNIT"
        ;;
    *)
        log "Nope. This OS will stuck on mod_php."
        ;;
    esac
}

function configureApache {
    local a2_en_mod=""
    local a2_dis_mod=""
    local a2_en_site=""
    local a2_dis_site=""
    local hostname=""

    log "Configure Apache Web server"

    hostname="$(cat /etc/hostname)"

    case "$OS" in
    "rhel7" | "rhel8" | "centos7" | "centos8")
        cat <<EOF >${APACHE_CONFIG_FILE} || abort "Unable to create and edit file '${APACHE_CONFIG_FILE}'"
DirectoryIndex index.php
DocumentRoot ${INSTALL_DIR}/

<Directory ${INSTALL_DIR}/>
    AllowOverride None

    ${APACHE_HTACCESS_SUBSTITUTION}
</Directory>

TimeOut 600
ProxyTimeout 600

<FilesMatch "\\.php$">
    <If "-f %{REQUEST_FILENAME}">
        SetHandler "proxy:unix:${PHP_FPM_SOCKET}|fcgi://localhost"
    </If>
</FilesMatch>
EOF

        test ! -d "$INSTALL_DIR" && (
            mkdir -p "$INSTALL_DIR" || abort "Unable to create directory '${INSTALL_DIR}'"
        )

        log "Change directory ownership"
        chown "$APACHE_USER":"$APACHE_GROUP" -R "${INSTALL_DIR}/" || abort "Unable to change ownership"

        log "SELinux: Allow Apache Web server to read/write files under ${INSTALL_DIR}/"
        chcon -t httpd_sys_content_t "${INSTALL_DIR}/" -R || abort "Unable to give read permissions recursively"
        chcon -t httpd_sys_rw_content_t "${INSTALL_DIR}/" -R || abort "Unable to give write permissions recursively"

        ## mpm_event is already enabled on RHEL 8:
        if [[ "$OS" != "rhel8" ]]; then
            log "Disable MPM prefork"
            sed -i "/.* mpm_prefork_module /s/^#*/#/" /etc/httpd/conf.modules.d/00-mpm.conf || abort "sed exited with error"
            log "Enable MPM event"
            sed -i "/^#.* mpm_event_module /s/^#//" /etc/httpd/conf.modules.d/00-mpm.conf || abort "sed exited with error"
        fi

        if [[ "$OS" != "centos8" ]]; then
            log "Disable MPM prefork"
            sed -i "/.* mpm_prefork_module /s/^#*/#/" /etc/httpd/conf.modules.d/00-mpm.conf || abort "sed exited with error"
            log "Enable MPM event"
            sed -i "/^#.* mpm_event_module /s/^#//" /etc/httpd/conf.modules.d/00-mpm.conf || abort "sed exited with error"
        fi

        unitctl "restart" "$APACHE_UNIT"
        ;;
    "sles15" | "opensuse15")
        a2_en_mod=$(command -v a2enmod)

        cat <<EOF >${APACHE_CONFIG_FILE} || abort "Unable to create and edit file '${APACHE_CONFIG_FILE}'"

ServerName ${hostname}

<VirtualHost *:80>
    ServerAdmin i-doit@example.net

    DirectoryIndex index.php
    DocumentRoot ${INSTALL_DIR}/

    <Directory ${INSTALL_DIR}/>
        AllowOverride None

        ${APACHE_HTACCESS_SUBSTITUTION}
    </Directory>

    TimeOut 600
    ProxyTimeout 600

    <FilesMatch "\\.php$">
        <If "-f %{REQUEST_FILENAME}">
            SetHandler "proxy:unix:${PHP_FPM_SOCKET}|fcgi://localhost"
        </If>
    </FilesMatch>

    LogLevel warn
    ErrorLog /var/log/apache2/error.log
    CustomLog /var/log/apache2/access.log combined
</VirtualHost>
EOF

        log "Change directory ownership"
        chown "$APACHE_USER":"$APACHE_GROUP" -R "${INSTALL_DIR}/" || abort "Unable to change ownership"

        log "Enable Apache module proxy"
        "$a2_en_mod" proxy || abort "Unable to enable Apache module proxy"
        log "Enable Apache module proxy_fcgi"
        "$a2_en_mod" proxy_fcgi || abort "Unable to enable Apache module proxy_fcgi"
        log "Enable Apache module rewrite"
        "$a2_en_mod" rewrite || abort "Unable to enable Apache module rewrite"
        log "Enable Apache module mod_access_compat"
        "$a2_en_mod" mod_access_compat || abort "Unable to enable Apache module mod_access_compat"

        unitctl "restart" "$APACHE_UNIT"
        ;;
    "debian11" | "debian12" | "ubuntu2004" | "ubuntu2204" | "ubuntu2404")
        a2_en_site=$(command -v a2ensite)
        a2_dis_site=$(command -v a2dissite)
        a2_en_mod=$(command -v a2enmod)
        a2_dis_mod=$(command -v a2dismod)

        cat <<EOF >${APACHE_CONFIG_FILE} || abort "Unable to create and edit file '${APACHE_CONFIG_FILE}'"
ServerName ${hostname}

<VirtualHost *:80>
    ServerAdmin i-doit@example.net

    DirectoryIndex index.php
    DocumentRoot ${INSTALL_DIR}/

    <Directory ${INSTALL_DIR}/>
        AllowOverride None

        ${APACHE_HTACCESS_SUBSTITUTION}
    </Directory>

    TimeOut 600
    ProxyTimeout 600

    <FilesMatch "\\.php$">
        <If "-f %{REQUEST_FILENAME}">
            SetHandler "proxy:unix:${PHP_FPM_SOCKET}|fcgi://localhost"
        </If>
    </FilesMatch>

    LogLevel warn
    ErrorLog \${APACHE_LOG_DIR}/error.log
    CustomLog \${APACHE_LOG_DIR}/access.log combined
</VirtualHost>
EOF

        log "Disable default VHost"
        "$a2_dis_site" 000-default || abort "Unable to disable default VHost"
        log "Change directory ownership"
        chown "$APACHE_USER":"$APACHE_GROUP" -R "${INSTALL_DIR}/" || abort "Unable to change ownership"
        log "Enable new VHost settings"
        "$a2_en_site" i-doit || abort "Unable to enable VHost settings"
        log "Enable Apache module rewrite"
        "$a2_en_mod" rewrite || abort "Unable to enable Apache module rewrite"
        log "Enable Apache module alias"
        "$a2_en_mod" alias || abort "Unable to enable Apache module alias"
        log "Disable Apache module mpm_prefork"
        "$a2_dis_mod" mpm_prefork || abort "Unable to enable Apache module mpm_prefork"
        log "Enable Apache module mpm_event"
        "$a2_en_mod" mpm_event || abort "Unable to enable Apache module mpm_event"
        log "Enable Apache module proxy"
        "$a2_en_mod" proxy || abort "Unable to enable Apache module proxy"
        log "Enable Apache module proxy_fcgi"
        "$a2_en_mod" proxy_fcgi || abort "Unable to enable Apache module proxy_fcgi"
        log "Enable Apache module setenvif"
        "$a2_en_mod" setenvif || abort "Unable to enable Apache module setenvif"
        log "Let every user read the logs"
        chmod 755 /var/log/apache2 || abort "Unable to change permissions"
        chmod 664 /var/log/apache2/* || abort "Unable to change permissions"
        unitctl "restart" "$APACHE_UNIT"
        ;;
    *)
        a2_en_site=$(command -v a2ensite)
        a2_dis_site=$(command -v a2dissite)
        a2_en_mod=$(command -v a2enmod)

        cat <<EOF >${APACHE_CONFIG_FILE} || abort "Unable to create and edit file '${APACHE_CONFIG_FILE}'"
ServerName ${hostname}

<VirtualHost *:80>
    ServerAdmin i-doit@example.net

    DocumentRoot ${INSTALL_DIR}/
    <Directory ${INSTALL_DIR}/>
        # See ${INSTALL_DIR}/.htaccess for details
        AllowOverride All
        Require all granted
    </Directory>

    LogLevel warn
    ErrorLog \${APACHE_LOG_DIR}/error.log
    CustomLog \${APACHE_LOG_DIR}/access.log combined
</VirtualHost>
EOF

        log "Disable default VHost"
        "$a2_dis_site" 000-default || abort "Unable to disable default VHost"
        log "Change directory ownership"
        chown "$APACHE_USER":"$APACHE_GROUP" -R "${INSTALL_DIR}/" || abort "Unable to change ownership"
        log "Enable new VHost settings"
        "$a2_en_site" i-doit || abort "Unable to enable VHost settings"
        log "Enable Apache module rewrite"
        "$a2_en_mod" rewrite || abort "Unable to enable Apache module rewrite"
        log "Let every user read the logs"
        chmod 755 /var/log/apache2 || abort "Unable to change permissions"
        chmod 664 /var/log/apache2/ || abort "Unable to change permissions"
        unitctl "restart" "$APACHE_UNIT"
        ;;
    esac
}

function configureMariaDB {
    log "Configure MariaDB DBMS"

    echo -e -n "Please enter the MariaDB hostname [leave empty for '${MARIADB_HOSTNAME}']: "
    read -r answer
    if [[ -n "$answer" ]]; then
        MARIADB_HOSTNAME="$answer"
    fi

    secureMariaDB

    # Check mariadb version
    local mariadb_version=""
    mariadb_version=$(mysql --version | head -n1 | sed -e 's/.* Distrib \([0-9]*\.[0-9]*\)\.[0-9]*.*/\1/')

    log "Prepare shutdown of MariaDB"
    "$MARIADB_BIN" \
        -h"$MARIADB_HOSTNAME" \
        -u"$MARIADB_SUPERUSER_USERNAME" -p"$MARIADB_SUPERUSER_PASSWORD" \
        -e"SET GLOBAL innodb_fast_shutdown = 0" || abort "Unable to prepare shutdown"
    unitctl "stop" "$MARIADB_UNIT"

    log "How many bytes of your RAM do you like to spend to MariaDB?"
    echo -n -e "You SHOULD give MariaDB ~ 50 per cent of your RAM. You can use G for Gigabytes or M for Megabytes, e.g. 1024M or 1G [leave empty for '${MARIADB_INNODB_BUFFER_POOL_SIZE}']: "

    read -r answer

    if [[ -n "$answer" ]]; then
        MARIADB_INNODB_BUFFER_POOL_SIZE="$answer"
    fi

    if [[ "$mariadb_version" != "10.11" ]]; then
        log "Move old MariaDB log files"
        mv /var/lib/mysql/ib_logfile[01] "$TMP_DIR" || abort "Unable to remove old log files"

        log "Configure MariaDB settings"
        cat <<EOF >"$MARIADB_CONFIG_FILE" || abort "Unable to create and edit file '${MARIADB_CONFIG_FILE}'"
[mysqld]

# This is the number 1 setting to look at for any performance optimization
# It is where the data and indexes are cached: having it as large as possible will
# ensure MySQL uses memory and not disks for most read operations.
# See https://mariadb.com/kb/en/innodb-buffer-pool/
# Typical values are 1G (1-2GB RAM), 5-6G (8GB RAM), 20-25G (32GB RAM), 100-120G (128GB RAM).
innodb_buffer_pool_size = ${MARIADB_INNODB_BUFFER_POOL_SIZE}
# Use multiple instances if you have innodb_buffer_pool_size > 10G, 1 every 4GB
innodb_buffer_pool_instances = 1
# Redo log file size, the higher the better.
# MySQL/MariaDB writes two of these log files in a default installation.
innodb_log_file_size = 512M
innodb_sort_buffer_size = 64M
sort_buffer_size = 262144 # default
join_buffer_size = 262144 # default
max_allowed_packet = 128M
max_heap_table_size = 32M
query_cache_min_res_unit = 4096
query_cache_type = 1
query_cache_limit = 5M
query_cache_size = 80M
tmp_table_size = 32M
max_connections = 200
innodb_file_per_table = 1
# Disable this (= 0) if you have only one to two CPU cores, change it to 4 for a quad core.
innodb_thread_concurrency = 0
# Disable this (= 0) if you have slow harddisks
innodb_flush_log_at_trx_commit = 1
innodb_flush_method = O_DIRECT
innodb_lru_scan_depth = 2048
table_definition_cache = 1024
table_open_cache = 2048
innodb_stats_on_metadata = 0
sql-mode = ""
EOF

    else
        cat <<EOF >"$MARIADB_CONFIG_FILE" || abort "Unable to create and edit file '${MARIADB_CONFIG_FILE}'"
[mysqld]
# This is the number 1 setting to look at for any performance optimization
# It is where the data and indexes are cached: having it as large as possible will
# ensure MySQL uses memory and not disks for most read operations.
# See https://mariadb.com/kb/en/innodb-buffer-pool/
# Typical values are 1G (1-2GB RAM), 5-6G (8GB RAM), 20-25G (32GB RAM), 100-120G (128GB RAM).
innodb_buffer_pool_size = 1G
# Redo log file size, the higher the better.
# MySQL/MariaDB writes one of these log files in a default installation.
innodb_log_file_size = 512M
innodb_sort_buffer_size = 64M
sort_buffer_size = 262144 # default
join_buffer_size = 262144 # default
max_allowed_packet = 128M
max_heap_table_size = 32M
query_cache_min_res_unit = 4096
query_cache_type = 1
query_cache_limit = 5M
query_cache_size = 80M
tmp_table_size = 32M
max_connections = 200
innodb_file_per_table = 1
# Disable this (= 0) if you have slow hard disks
innodb_flush_log_at_trx_commit = 1
innodb_flush_method = O_DIRECT
innodb_lru_scan_depth = 2048
table_definition_cache = 1024
table_open_cache = 2048
innodb_stats_on_metadata = 0
sql-mode = ""
EOF
    fi

    if [[ -d "/var/log/mysql" ]]; then
        log "Let every user read the logs"
        chmod 755 /var/log/mysql
        chmod 664 /var/log/mysql/
    fi

unitctl "start" "$MARIADB_UNIT"

}

function secureMariaDB {

    local mariadb_version=""
    mariadb_version=$(mysql --version | head -n1 | sed -e 's/.* Distrib \([0-9]*\.[0-9]*\)\.[0-9]*.*/\1/')

    echo -n -e \
        "Please enter a new password for MariaDB's super user '${MARIADB_SUPERUSER_USERNAME}' [leave empty for '${MARIADB_SUPERUSER_PASSWORD}']: "

    read -r answer

    if [[ -n "$answer" ]]; then
        MARIADB_SUPERUSER_PASSWORD="$answer"
    fi

    log "Set $MARIADB_SUPERUSER_USERNAME password and plugin 'mysql_native_password'"
    case "$mariadb_version" in

    "10.11")
        "$MARIADB_BIN" \
            -h"$MARIADB_HOSTNAME" \
            -u"$MARIADB_SUPERUSER_USERNAME" \
            -p"$MARIADB_SUPERUSER_PASSWORD" \
            -e"ALTER USER 'root'@'localhost' IDENTIFIED VIA mysql_native_password USING PASSWORD('${MARIADB_SUPERUSER_PASSWORD}');" || abort "SQL statement failed"
        ;;

    "10.4" | "10.5" | "10.6")
        "$MARIADB_BIN" \
            -h"$MARIADB_HOSTNAME" \
            -u"$MARIADB_SUPERUSER_USERNAME" \
            -p"$MARIADB_SUPERUSER_PASSWORD" \
            -e"SET PASSWORD FOR '${MARIADB_SUPERUSER_USERNAME}'@'localhost' = PASSWORD('${MARIADB_SUPERUSER_PASSWORD}');" \
            -e"ALTER USER '${MARIADB_SUPERUSER_USERNAME}'@'localhost' IDENTIFIED VIA mysql_native_password USING PASSWORD('${MARIADB_SUPERUSER_PASSWORD}');" || abort "SQL statement failed"
        ;;

    "10.1" | "10.2" | "10.3")
        "$MARIADB_BIN" \
            -h"$MARIADB_HOSTNAME" \
            -u"$MARIADB_SUPERUSER_USERNAME" \
            -p"$MARIADB_SUPERUSER_PASSWORD" \
            -e"UPDATE mysql.user SET Password=PASSWORD('${MARIADB_SUPERUSER_PASSWORD}'), plugin='mysql_native_password' WHERE User='${MARIADB_SUPERUSER_USERNAME}';" || abort "SQL statement failed"
        ;;

    *)
        abort "MariaDB ${mariadb_version} is not supported. Please follow the system requirements. We recommend version ${RECOMMENDED_MARIADB_VERSION}."
        ;;
    esac

    case "$OS" in
    "rhel7" | "rhel8" | "centos7" | "centos8")
        log "Allow $MARIADB_SUPERUSER_USERNAME login only from localhost"
        "$MARIADB_BIN" \
            -h"$MARIADB_HOSTNAME" \
            -u"$MARIADB_SUPERUSER_USERNAME" \
            -p"$MARIADB_SUPERUSER_PASSWORD" \
            -e"DELETE FROM mysql.user WHERE User='${MARIADB_SUPERUSER_USERNAME}' AND Host NOT IN ('localhost', '127.0.0.1', '::1');" || abort "SQL statement failed"

        log "Remove anonymous user"
        "$MARIADB_BIN" \
            -h"$MARIADB_HOSTNAME" \
            -u"$MARIADB_SUPERUSER_USERNAME" \
            -p"$MARIADB_SUPERUSER_PASSWORD" \
            -e"DELETE FROM mysql.user WHERE User='';" || abort "SQL statement failed"

        log "Remove test database"
        "$MARIADB_BIN" \
            -h"$MARIADB_HOSTNAME" \
            -u"$MARIADB_SUPERUSER_USERNAME" \
            -p"$MARIADB_SUPERUSER_PASSWORD" \
            -e"DELETE FROM mysql.db WHERE Db='test' OR Db='test_%';" || abort "SQL statement failed"

        log "Flush MariaDB user privileges"
        "$MARIADB_BIN" \
            -h"$MARIADB_HOSTNAME" \
            -u"$MARIADB_SUPERUSER_USERNAME" \
            -p"$MARIADB_SUPERUSER_PASSWORD" \
            -e"FLUSH PRIVILEGES;" || abort "SQL statement failed"
        ;;

    "sles15" | "opensuse15" | "debian11" | "ubuntu2004" | "ubuntu2204" | "ubuntu2404")
        log "Allow $MARIADB_SUPERUSER_USERNAME login only from localhost"
        "$MARIADB_BIN" \
            -h"$MARIADB_HOSTNAME" \
            -u"$MARIADB_SUPERUSER_USERNAME" \
            -p"$MARIADB_SUPERUSER_PASSWORD" \
            -e"DELETE FROM mysql.user WHERE User='${MARIADB_SUPERUSER_USERNAME}' AND Host NOT IN ('localhost', '127.0.0.1', '::1');" || abort "SQL statement failed"

        log "Remove anonymous user"
        "$MARIADB_BIN" \
            -h"$MARIADB_HOSTNAME" \
            -u"$MARIADB_SUPERUSER_USERNAME" \
            -p"$MARIADB_SUPERUSER_PASSWORD" \
            -e"DELETE FROM mysql.user WHERE User='';" || abort "SQL statement failed"

        log "Remove test database"
        "$MARIADB_BIN" \
            -h"$MARIADB_HOSTNAME" \
            -u"$MARIADB_SUPERUSER_USERNAME" \
            -p"$MARIADB_SUPERUSER_PASSWORD" \
            -e"DELETE FROM mysql.db WHERE Db='test' OR Db='test_%';" || abort "SQL statement failed"

        log "Flush MariaDB user privileges"
        "$MARIADB_BIN" \
            -h"$MARIADB_HOSTNAME" \
            -u"$MARIADB_SUPERUSER_USERNAME" \
            -p"$MARIADB_SUPERUSER_PASSWORD" \
            -e"FLUSH PRIVILEGES;" || abort "SQL statement failed"
        ;;
    esac
}

function prepareIDoit {
    local file="${TMP_DIR}/i-doit.zip"
    local update_file_url=""
    local variant=""
    local parse_updates_script=""
    local url=""
    local version=""
    local release_date=""

    log "Cleanup VHost directory"
    rm -rf "${INSTALL_DIR:?}/"* || abort "Unable to remove files"
    rm -f "${INSTALL_DIR}"/.htaccess || abort "Unable to remove files"

    log ""
    log "For evaluation use \033[32mEVAL\033[0m"
    log "If you have a license use \033[32mPRO\033[0m"
    log "If you want the open version use \033[32mOPEN\033[0m"
    log ""

    echo -n -e "Which variant of i-doit do you like to install? [EVAL|pro|open]: "

    read -r wanted_variant

    case "$wanted_variant" in
    "" | "EVAL" | "Eval" | "eval")
        update_file_url="$UPDATE_FILE_EVAL"
        variant="eval"
        ;;
    "PRO" | "Pro" | "pro")
        update_file_url="$UPDATE_FILE_PRO"
        variant="pro"
        ;;
    "OPEN" | "Open" | "open")
        update_file_url="$UPDATE_FILE_OPEN"
        variant="open"
        ;;
    *)
        abort "Unknown variant"
        ;;
    esac

    log "Install i-doit $variant"

    case "$variant" in
    "pro" | "open")
        log "Identify latest version of i-doit $variant"
        test ! -f "$TMP_DIR/updates.xml" &&
            "$WGET_BIN" --quiet -O "${TMP_DIR}/updates.xml" "$update_file_url"
        test -f "$TMP_DIR/updates.xml" ||
            abort "Unable to fetch file from '${update_file_url}'"

        parse_updates_script="${TMP_DIR}/parseupdates.php"

        cat <<EOF >"$parse_updates_script" || abort "Unable to create and edit file '${parse_updates_script}'"
<?php
\$attribute = \$argv[1];
\$xml = new SimpleXMLElement(trim(file_get_contents('${TMP_DIR}/updates.xml')));
echo \$xml->updates->update[count(\$xml->updates->update) - 1]->\$attribute;
EOF

        url=$($PHP_BIN "$parse_updates_script" "filename" | sed "s/-update.zip/.zip/")
        test -n "$url" || abort "Missing URL"

        version=$($PHP_BIN "$parse_updates_script" "version")
        test -n "$version" || abort "Missing version"

        release_date=$($PHP_BIN "$parse_updates_script" "release")
        test -n "$release_date" || abort "Missing release date"

        log "Download i-doit $variant $version (released on ${release_date})"

        "$WGET_BIN" --quiet -O "$file" "$url" || abort "Unable to download installation file"

        ;;
    "eval")
        log "Download i-doit EVAL version"

        "$WGET_BIN" --quiet -O "$file" "$update_file_url" || abort "Unable to download installation file"

        ;;
    *)
        abort "Unknown variant"
        ;;
    esac

    cp "$file" "${INSTALL_DIR}/i-doit.zip" || abort "Unable to copy installation file"

    log "Unzip package"
    cd "$INSTALL_DIR" || abort "Unable to change to installation directory '${INSTALL_DIR}'"
    "$UNZIP_BIN" -q i-doit.zip || abort "Unable to unzip file"

    log "Prepare files and directories"
    rm i-doit.zip || abort "Unable to remove downloaded file"
    chown "$APACHE_USER":"$APACHE_GROUP" -R . || abort "Unable to change ownership"
    find . -type d -name \* -exec chmod 775 {} \; || abort "Unable to change directory permissions"
    find . -type f -exec chmod 664 {} \; || abort "Unable to change file permissions"
}

function updateApacheConfig {
    local htaccessFile="${INSTALL_DIR}/.htaccess"

    log "Update Apache's VHost config from i-doit's htaccess file"

    sed -i \
        -e "/${APACHE_HTACCESS_SUBSTITUTION}/ {" \
        -e "r ${htaccessFile}" \
        -e "d" \
        -e "}" \
        "$APACHE_CONFIG_FILE" || abort "Unable to change config file"

    unitctl "restart" "$APACHE_UNIT"
}

function installIDoit {
    local prefix="php"
    local console="${INSTALL_DIR}/console.php"

    log "Install i-doit via console.php"
    echo -n -e \
        "Please enter a Admin Center password [leave empty for '${IDOIT_ADMIN_CENTER_PASSWORD}']: "
    read -r adminCenterPass

    if [[ -n "$adminCenterPass" ]]; then
        IDOIT_ADMIN_CENTER_PASSWORD="$adminCenterPass"
    fi

    echo -n -e \
        "Please enter a username for a new MySQL user (This user will be authorized to the i-doit databases only) [leave empty for '${MARIADB_IDOIT_USERNAME}']: "
    read -r mariaDBidoitUsername

    if [[ -n "$mariaDBidoitUsername" ]]; then
        MARIADB_IDOIT_USERNAME="$mariaDBidoitUsername"
    fi

    echo -n -e \
        "Please enter a password for a the new MySQL user [leave empty for '${MARIADB_IDOIT_PASSWORD}']: "
    read -r mariaDBidoitPassword

    if [[ -n "$mariaDBidoitPassword" ]]; then
        MARIADB_IDOIT_PASSWORD="$mariaDBidoitPassword"
    fi

    sudo -u "${APACHE_USER}" "${prefix}" "${console}" install \
        -u "$MARIADB_SUPERUSER_USERNAME" \
        -p "$MARIADB_SUPERUSER_PASSWORD" \
        --host="$MARIADB_HOSTNAME" \
        -d idoit_system \
        -U "$MARIADB_IDOIT_USERNAME" \
        -P "$MARIADB_IDOIT_PASSWORD" \
        --admin-password "$IDOIT_ADMIN_CENTER_PASSWORD" \
        -n || abort "Installation of i-doit failed"

    config_file="${INSTALL_DIR}/src/config.inc.php"

    log "Fix configuration file '${config_file}'"

    chown "$APACHE_USER":"$APACHE_GROUP" "$config_file" || abort "Unable to change ownership"
}

function create_tenant {
    local prefix="php"
    local console="${INSTALL_DIR}/console.php"
    local tenant_name="Your company name"

    log "Install i-doit via console.php"
    echo -n -e \
        "Please enter a tenant name [leave empty for '${tenant_name}']: "
    read -r tenantName

    if [[ -n "$tenantName" ]]; then
        tenant_name="$tenantName"
    fi

    sudo -u "${APACHE_USER}" "${prefix}" "${console}" tenant-create \
        -u "$MARIADB_SUPERUSER_USERNAME" \
        -p "$MARIADB_SUPERUSER_PASSWORD" \
        -U "$MARIADB_IDOIT_USERNAME" \
        -P "$MARIADB_IDOIT_PASSWORD" \
        -d idoit_data \
        -t "$tenant_name" \
        -n || abort "Creating tenant failed"

    log "Tenant '$tenant_name' created"
}

function deployScriptSettings {
    local settings_dir=""

    log "Deploy script settings"

    settings_dir=$(dirname "$SCRIPT_SETTINGS")

    test -d "$settings_dir" || (
        mkdir -p "$settings_dir" || abort "Unable to create directory '$settings_dir'"
    )

    cat <<EOF >"$SCRIPT_SETTINGS" || abort "Unable to create and edit file '${SCRIPT_SETTINGS}'"
#!/bin/bash

export CONSOLE_BIN="$CONSOLE_BIN"
export APACHE_USER="$APACHE_USER"
export SYSTEM_DATABASE="idoit_system"
export TENANT_DATABASE="idoit_data"
export TENANT_ID="1"
export MARIADB_USERNAME="$MARIADB_IDOIT_USERNAME"
export MARIADB_PASSWORD="$MARIADB_IDOIT_PASSWORD"
export MARIADB_HOSTNAME="$MARIADB_HOSTNAME"
export INSTANCE_PATH="$INSTALL_DIR"
export IDOIT_USERNAME="admin"
export IDOIT_PASSWORD="admin"
export BACKUP_DIR="$BACKUP_DIR"
# Max. age of backup files (in days):
export BACKUP_AGE=30
EOF
}

function deployConsole {
    log "Deploy i-doit console"
    deployScript idoit
}

function deployJobScript {
    log "Deploy i-doit jobs"
    deployScript idoit-jobs
}

function deployCronJobs {
    local download_url="https://raw.githubusercontent.com/i-doit/scripts/main/cron"
    local file="$TMP_DIR/cron"

    test ! -f "$file" && (
        "$WGET_BIN" --quiet -O "$file" "$download_url" || abort "Unable to fetch file from '${download_url}'"
    )

    sed -i -- "s/www-data/${APACHE_USER}/g" "$file" || abort "Unable to set Apache user"

    chmod 644 "$file" || abort "Unable to set read/write bits"

    mv "$file" "$CRON_FILE" || abort "Unable to move file to '/etc/cron.d/i-doit'"
}

function deployBackupAndRestore {
    log "Deploy backup and restore scripts"

    deployScript idoit-backup
    deployScript idoit-restore

    log "Create the first backup"
    /usr/local/bin/idoit-backup || abort "Backup script returned with error"
}

function deployScript {
    local file="$1"
    local tmp_file="${TMP_DIR}/$file"
    local url="https://raw.githubusercontent.com/i-doit/scripts/main/$file"

    log "Deploy script '$file'"

    test ! -f "$tmp_file" && (
        "$WGET_BIN" --quiet -O "$tmp_file" "$url" || abort "Unable to fetch file from '${url}'"
    )

    chmod 775 "$tmp_file" || abort "Unable to set read/write/executable bits"

    mv "$tmp_file" "/usr/local/bin/$file" || abort "Unable to move file to '/usr/local/bin/'"
}

function unitctl {
    local action="$1"
    local unit="$2"

    log "${action^} $unit"

    systemctl -q "$action" "${unit}.service" || abort "Failed to $action $unit"
}

function setup {
    # We need English to check some command outputs:
    if locale -a | grep "^en_US.utf8" >/dev/null; then
        export LC_ALL="en_US.utf8"
        export LANG="en_US.utf8"
        export LANGUAGE="en_US.utf8"
    elif locale -a | grep "^en_GB.utf8" >/dev/null; then
        export LC_ALL="en_GB.utf8"
        export LANG="en_GB.utf8"
        export LANGUAGE="en_GB.utf8"
    elif locale -a | grep "^C.UTF-8" >/dev/null; then
        export LC_ALL="C.UTF-8"
        export LANG="C.UTF-8"
        export LANGUAGE="C.UTF-8"
    elif locale -a | grep "^C.utf8" >/dev/null; then
        export LC_ALL="C.utf8"
        export LANG="C.utf8"
        export LANGUAGE="C.utf8"
    else
        log "This script may fail because it depends on US/GB English locale. We try it anyway…"
    fi

    test "$(whoami)" = "root" || abort "Superuser rights required"

    mkdir -p "$TMP_DIR" || abort "Unable to create temporary directory"
}

function tearDown {
    test -d "$TMP_DIR" && (rm -rf "$TMP_DIR" || echo "Failed to cleanup" 1>&2)
}

function showUsage {
    log "Usage: $BASENAME [OPTIONS]"
    log ""
    log "Options:"
    log ""
    log "    -h, --help      Print usage"
    log "    -v, --version   Print version"
}

function printVersion {
    log "$PROJECT_VERSION"
}

function log {
    echo -e "$1"
}

function askYesNo {
    echo -n -e "$1 [Y]es [n]o: "

    read -r answer

    case "$answer" in
    "" | "Y" | "Yes" | "y" | "yes")
        return 0
        ;;
    "No" | "no" | "n" | "N")
        return 1
        ;;
    *)
        log "Sorry, what do you mean?"
        askYesNo "$1"
        ;;
    esac
}

function askNoYes {
    echo -n -e "$1 [y]es [N]o: "

    read -r answer

    case "$answer" in
    "" | "No" | "no" | "n" | "N")
        return 0
        ;;
    "Y" | "Yes" | "y" | "yes")
        return 1
        ;;
    *)
        log "Sorry, what do you mean?"
        askNoYes "$1"
        ;;
    esac
}

function finish {
    log "Done. Have fun :-)"
    exit 0
}

function abort {
    echo -e "$1" 1>&2
    echo "Operation failed. Please check what is wrong and try again." 1>&2
    exit 1
}

function cancel {
    echo "Bye"
    exit 0
}

##--------------------------------------------------------------------------------------------------

if [[ "${BASH_SOURCE[0]}" = "$0" ]]; then
    trap tearDown EXIT

    ARGS=$(getopt \
        -o vh \
        --long help,version -- "$@" 2>/dev/null)

    eval set -- "$ARGS"

    while true; do
        case "$1" in
        -h | --help)
            showUsage
            exit 0
            ;;
        -v | --version)
            printVersion
            exit 0
            ;;
        --)
            shift
            break
            ;;
        *)
            log "Unkown option '${1}'."
            showUsage
            exit 1
            ;;
        esac
    done

    setup && execute && finish
fi