#!/usr/bin/env bash

# Author        : Allan Christensen
# First Created : 05012022 (DD-MM-YYYY)
# Description   : Installs DokuWiki on Ubuntu 24.04
# License       : MIT License (see LICENSE file for details)

#
# Are we root
#
if [[ $(id -u) -ne 0 ]]; then echo "" && echo "Must be root or use sudo" && echo "" ; exit 1 ; fi

#
# Get php-fpm version
#
phpfpm=$(systemctl list-unit-files --type=service | awk '/php[0-9]+\.[0-9]+-fpm\.service/ {sub(".service","",$1); print $1; exit}')
if [[ -z "$phpfpm" ]]; then printf "\nUnable to detect php-fpm version. Is PHP-FPM installed?\n\n" ; exit 1 ; fi

#
# Check if required services are running or not
# 
for svc in nginx "$phpfpm"; do systemctl is-active --quiet "$svc" || { printf "\n%s is not running, cannot continue...\n\n" "${svc^}" ; exit 1 ; }; done

#
# Define variables and functions
#
hostname="$1"

#
# Function usage
#
usage () {
    printf -- "\ndokuwikiinstall\n\n"
    printf -- "Installs DokuWiki on Ubuntu\n\n"
    printf -- "Usage:\n"
    printf -- "sudo ./dokuwikiinstall <domain>\n"
    printf -- "Examples:\n"
    printf -- "sudo ./dokuwikiinstall wiki.something.xyz\n\n"
}

#
# Parse and validate input
#
if [[ $# -ne 1 ]]; then
    usage
    printf "ERROR: Exactly one argument (the domain ony).\n\n"
    exit 1
fi

# Convert to lowercase (domains are case-insensitive)
hostname=$(echo "$hostname" | tr '[:upper:]' '[:lower:]')

# Ensure domain is not empty
if [[ -z "$hostname" ]]; then
    printf "ERROR: Domain cannot be empty.\n\n"
    usage
    exit 1
fi

# Disallow spaces, slashes, or underscores
if [[ "$hostname" =~ [[:space:]/_] ]]; then
    printf "ERROR: Domain cannot contain spaces, slashes, or underscores.\n\n"
    exit 1
fi

# Validate domain format (RFC 1123)
if [[ ! "$hostname" =~ ^([a-z0-9]+(-[a-z0-9]+)*\.)+[a-z]{2,}$ ]]; then
    printf "ERROR: Invalid domain format.\n"
    printf "Example of valid input: wiki.example.com\n\n"
    exit 1
fi

# Prevent accidental overwrite of existing Nginx config
if [[ -f "/etc/nginx/conf.d/${hostname}.conf" ]]; then
    printf "\nERROR: A configuration file already exists for %s.\n" "$hostname"
    printf "Refusing to overwrite existing site.\n\n"
    exit 1
fi

# Check for existing references in other Nginx configs
hostcheck=$(grep -r --exclude="README.md" "$hostname" /etc/nginx/ 2>/dev/null || true)
if [[ -n "$hostcheck" ]]; then
    printf "\nFound existing configuration mentioning %s — aborting to avoid collision.\n\n" "$hostname"
    exit 1
fi

#
# Let's go
#
clear

#
# Ensure curl is available
#
for tool in curl unzip wget; do dpkg -s "$tool" &>/dev/null || apt install -y "$tool" ; done

#
# Clone nginx-snippets; if nginx-snippets exists then just pull latest changes
#
nginxsnippets="/etc/nginx/nginx-snippets"
repo="https://git.x-files.dk/webserver/nginx-snippets.git"
if [[ -d "$nginxsnippets/.git" ]]; then git -C "$nginxsnippets" pull --quiet; else git clone --quiet "$repo" "$nginxsnippets"; fi

#
# Download the latest DokuWiki
#
wikidir="/var/www/html/$hostname" ; mkdir -p "$wikidir"
curl -sL https://download.dokuwiki.org/src/dokuwiki/dokuwiki-stable.tgz | tar -xzf - -C "$wikidir" --strip-components=1 || { echo "Download or extraction failed"; exit 1; }
chown -R www-data: "$wikidir"

#
# Create a DokuWiki nginx configuration file
#
cp "$nginxsnippets/hostfiles/dokuwiki.80.conf" /etc/nginx/conf.d/"$hostname".conf
sed -i -- "s/DOMAIN/$hostname/g" /etc/nginx/conf.d/"$hostname".conf
sed -i "s/PHPVERSION/$phpfpm/" /etc/nginx/conf.d/"$hostname".conf

#
# Restarting Nginx and Phpfpm for changes to take effect
#
printf "\nRestarting services...\n"
systemctl restart "$phpfpm"
systemctl restart nginx

#
# Create postinstall script
#
cat > /tmp/dokuwiki-postinstall <<EOF
#!/usr/bin/env bash

#
# DokuWiki Postinstall Script
#

#
# Are we root?
#
if [[ $(id -u) -ne 0 ]]; then echo "" && echo "Must be root or use sudo" && echo "" ; exit ; fi

#
# Hardening of DokuWiki
#
sed -i 's/^[[:space:]]*#\s*location /location /g' /etc/nginx/conf.d/"$hostname".conf

#
# Restart Nginx for changes to take effect
#
systemctl restart nginx

#
# Cleaning up
#
rm -f /tmp/dokuwiki-postinstall
EOF

chmod 755 /tmp/dokuwiki-postinstall

#
# DokuWiki postinstall notice
#
wikinotice=$(cat <<EOF
-----------------------------------------------------------------------------------
IMPORTANT: Go to http://$hostname/install.php in order to complete the installation:

Don't worry about the warning on the right side of the page this will be
fixed as there still is a post install step to do.

Once done run the following command as root or using sudo.

sudo /tmp/dokuwiki-postinstall
-----------------------------------------------------------------------------------
EOF
)

#
# Print notice
#
printf '\n%s\n' "$wikinotice"

#
# All done
#
printf "\nAll Done...\n"

#
# End of script
#