#!/usr/bin/env bash
# Pi-hole: A black hole for Internet advertisements
# (c) 2015, 2016 by Jacob Salmela
# Network-wide ad blocking via your Raspberry Pi
# http://pi-hole.net
# Completely uninstalls Pi-hole
#
# Pi-hole is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 2 of the License, or
# (at your option) any later version.

# Must be root to uninstall
if [[ $EUID -eq 0 ]];then
	echo "You are root."
else
	echo "sudo will be used for the install."
  # Check if it is actually installed
  # If it isn't, exit because the unnstall cannot complete
  if [[ $(dpkg-query -s sudo) ]];then
		export SUDO="sudo"
  else
    echo "Please install sudo or run this as root."
    exit 1
  fi
fi

function removeAndPurge {
	# Purge dependencies
	echo "Purging dependencies!"
	$SUDO apt-get -y remove --purge dnsutils bc toilet
	$SUDO apt-get -y remove --purge dnsmasq
	$SUDO apt-get -y remove --purge lighttpd php5-common php5-cgi php5

	# Remove dependency config files
	echo "Removing dnsmasq config files..."
	$SUDO rm /etc/dnsmasq.conf /etc/dnsmasq.conf.orig /etc/dnsmasq.d/01-pihole.conf &> /dev/null

	# Call removeNoPurge to remove PiHole specific files
	removeNoPurge
}

function removeNoPurge {
	# Only web directories/files that are created by pihole should be removed.
	echo "Removing the Pi-hole Web server files..."
	$SUDO rm -rf /var/www/html/admin &> /dev/null
	$SUDO rm -rf /var/www/html/pihole &> /dev/null
	$SUDO rm /var/www/html/index.lighttpd.orig &> /dev/null

	# If the web directory is empty after removing these files, then the parent html folder can be removed.
	if [ -d "/var/www/html" ]; then
		if [[ ! "$(ls -A /var/www/html)" ]]; then
    			$SUDO rm -rf /var/www/html &> /dev/null
		fi
	fi

	# Attempt to preserve backwards compatibility with older versions
	# to guarantee no additional changes were made to /etc/crontab after
	# the installation of pihole, /etc/crontab.pihole should be permanently
	# preserved.
	if [[ -f /etc/crontab.orig ]]; then
		echo "Initial Pi-hole cron detected.  Restoring the default system cron..."
		$SUDO mv /etc/crontab /etc/crontab.pihole
		$SUDO mv /etc/crontab.orig /etc/crontab
		$SUDO service cron restart
	fi

	# Attempt to preserve backwards compatibility with older versions
	if [[ -f /etc/cron.d/pihole ]];then
		echo "Removing cron.d/pihole..."
		$SUDO rm /etc/cron.d/pihole &> /dev/null
	fi

	echo "Removing config files and scripts..."
	$SUDO rm -rf /etc/lighttpd/ &> /dev/null
	$SUDO rm /var/log/pihole.log &> /dev/null
	$SUDO rm /usr/local/bin/gravity.sh &> /dev/null
	$SUDO rm /usr/local/bin/chronometer.sh &> /dev/null
	$SUDO rm /usr/local/bin/whitelist.sh &> /dev/null
	$SUDO rm /usr/local/bin/piholeLogFlush.sh &> /dev/null
	$SUDO rm /usr/local/bin/piholeDebug.sh &> /dev/null
	$SUDO rm -rf /var/log/*pihole* &> /dev/null
	$SUDO rm -rf /etc/pihole/ &> /dev/null
	$SUDO rm -rf /etc/.pihole/ &> /dev/null

}

######### SCRIPT ###########
echo "WARNING: This is destructive if run on any non-Debian based OS"
echo "(SAFE TO RUN ON RASPBIAN)"
while true; do
	read -p "Do you wish to purge PiHole's dependencies from your OS?" yn
	case $yn in
		[Yy]* ) removeAndPurge; break;;
	
		[Nn]* ) removeNoPurge; break;;
	esac
done