#!/bin/bash

#######
### Copy customized jails, filters and action configuration files to fail2ban
### directory and activate them
#######


### set script output colours
normal="\e[0m"
err="\e[1;31m"
ok="\e[32m"
lit="\e[93m"
info="\e[96m"
note="\e[95m"


### functions

function copyFailure {
    echo
    echo -e "${err}There was a problem backing up your current configuration."
    echo -e "This suggests some kind of permissions error. Please remedy this" \
        "and rerun"
    echo -e "this script."
    echo
    echo -e "${note}Error backing up: ${lit}$1"
    echo
    echo -e "${err}Exiting.${normal}"
    echo
    exit 100
}

### end of functions


### pre-requisites
# exit script if fail2ban is not installed
if ! [ -x "$(command -v fail2ban-client)" ]; then
    echo
    echo -e "${err}Cannot find fail2ban, is it installed? Exiting script." \
        "${normal}"
    echo
    exit 1
fi

# check if running as root
if [ "$(id -u)" -ne 0 ]; then
    echo
    echo -e "${err}This script MUST be run as ROOT. Exiting.${normal}"
    echo
    exit 2
fi


### default values for variables
F2B_DIR="$1"
echo "(testing: base-dir is: ${F2B_DIR})"


### user info preamble
echo
echo -e "${note}------------------------------------------------------------" \
    "--------------------${normal}"
echo -e "${info}This script will copy customized configuration files to your" \
    "fail2ban"
echo -e "configuration directory.  It will backup any existing files with the" \
    "extension"
echo -e "${note}'.original'${info}.${normal}"
echo
echo -e "${info}Please ensure you have reviewed the ${note}README${info} in" \
    "this git archive and/or it's"
echo -e "associated wiki or the blog post at${note}" \
    "https://mytechiethoughts.com${info} to understand"
echo -e "how to customize these template files.${normal}"
echo -e "${note}------------------------------------------------------------" \
    "--------------------${normal}"
echo


### copy template files
# note: prefixing cp with '\' to override any alias settings
# copy .local files
if [ "$(\cp --force --backup=simple --suffix=.original \
    etc/fail2ban/*.local "${F2B_DIR}/")" -ne 0 ]; then
        copyFailure 'general config files (.local)'
fi
echo -e "${info}Copy general configuration files${normal} -- ${ok}[OK]${normal}"

# copy action configuration files
if [ "$(\cp --force --backup=simple --suffix=.original \
    etc/fail2ban/action.d/* "${F2B_DIR}/action.d/")" -ne 0 ]; then
        copyFailure 'action files'
fi
echo -e "${info}Copy action configuration files${normal} -- ${ok}[OK]${normal}"

# copy filter configuration files
if [ "$(\cp --force --backup=simple --suffix=.original \
    etc/fail2ban/filter.d/* "${F2B_DIR}/filter.d/")" -ne 0 ]; then
        copyFailure 'filter files'
fi
echo -e "${info}Copy filter configuration files${normal} -- ${ok}[OK]${normal}"

# copy jail configuration files
if [ "$(\cp --force --backup=simple --suffix=.original \
    etc/fail2ban/jail.d/* "${F2B_DIR}/jail.d/")" -ne 0 ]; then
        copyFailure 'jail files'
fi
echo -e "${info}Copy jail configuration files${normal} -- ${ok}[OK]${normal}"


### user post-amble
echo
echo -e "${note}------------------------------------------------------------" \
    "--------------------${normal}"
echo -e "${ok}Script operations completed successfully!"
echo
echo -e "${info}You can now customize the template files if/as you desire." \
    "Then do the"
echo -e "following to load and confirm your new configuration:${normal}"
echo -e "1. systemctl restart fail2ban.service"
echo -e "2. systemctl --full --no-pager status fail2ban.service"
echo -e "3. fail2ban-client status"
echo
echo -e "${note}To revert your configuration, simply copy the ${lit}.original" \
    "${note}files over the modified"
echo -e "files.  For example, ${lit}cp jail.local.original jail.local${normal}"
echo -e "${note}--------------------------------Script--Complete------------" \
    "--------------------${normal}"
echo


### exit gracefully
exit 0