#!/bin/bash

# kf2-srv is a command line tool for managing a set of Killing Floor 2 servers.
# Copyright (C) 2019 GenZmeY
# mailto: genzmey@gmail.com
# 
# This program 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 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 General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <https://www.gnu.org/licenses/>.

source /etc/steamcmd/steamcmd.conf
source /etc/kf2-srv/kf2-srv.conf

ScriptFullname=$(readlink -e "$0")
ScriptName=$(echo "$ScriptFullname" | awk -F '/' '{print $NF;}')
AppNum="232130"
InstallDir="/usr/games/kf2-srv"
AppBin="$InstallDir/Binaries/Win64/KFGameSteamServer.bin.x86_64"
DefaultConfigDir="$InstallDir/KFGame/Config"
InstanceConfigDir="$DefaultConfigDir/instances"
InstanceConfigLnk="/etc/kf2-srv/instances"
MainConfigTemplate="/etc/kf2-srv/main.conf.template"

function show_help ()
{
	echo "kf2-srv"
	echo ""
	echo "Usage:"
	echo "$ScriptName OPTION  [INSTANCE]"
	echo ""
	echo "Mandatory arguments to long options are mandatory for short options too."
	echo "  -n, --new      INSTANCE   TODO: description"
	echo "  -d, --delete  [INSTANCE]  TODO: description"
	echo "  -l, --list                TODO: description"
	echo "  -s, --status  [INSTANCE]  TODO: description"
	echo "  -u, --update              TODO: description"
	echo "  -r. --run                 TODO: description"
	echo "      --start   [INSTANCE]  TODO: description"
	echo "      --stop    [INSTANCE]  TODO: description"
	echo "      --enable  [INSTANCE]  TODO: description"
	echo "      --disable [INSTANCE]  TODO: description"
	echo "      --map-sync            TODO: description"
	echo "      --ban-sync            TODO: description"
	echo "      --map-rotate-save     TODO: description"
	echo "      --map-rotate-load     TODO: description"
	echo "  -h, --help                display this help and exit"
}

# Use this function with non-root user only!!!
function run_as_root () # $@: Args
{
	if [[ -n $(groups "$USER" | grep -Fo 'wheel') ]]; then
		sudo "$ScriptFullname" $@
	else
		echo "You must be root or sudo-user to run this command."
		return 1
	fi
}

function service_name () # $1: Instance
{
	echo "kf2-srv@$1.service"
}

function show_instances ()
{
	find "$InstanceConfigDir" -maxdepth 1 -mindepth 1 -type d -printf "%f\n"
}

function instance_exists () # $1: Instance
{
	if show_instances | grep -qP "^.*[ ]*$1[ ]*.*$" ; then
		return 0
	else
		return 1
	fi
}

function server_exists ()
{
	if [[ -n $(ls "$InstallDir") ]]; then
		return 0
	else
		return 1
	fi
}

function updates_aviable ()
{
	# TODO: implementation
	return 0
}

function new_instance () # $1: InstanceName
{
	local Instance="$1"
	if [[ -z "$Instance" ]]; then
		echo "Name of instance must be set"
		exit 1
	elif ! server_exists; then
		echo "You must install server first"
		echo "Run \"$ScriptName --update\" to install it"
		exit 1
	elif instance_exists "$Instance"; then
		echo "Instance $Instance already exists"
		exit 1
	fi

	local InstanceDir="$InstanceConfigDir/$Instance"
	if [[ -d "$InstanceDir" ]]; then
		echo "$InstanceDir already exists"
		exit 1
	fi

	mkdir -p "$InstanceDir/LinuxServer" && chown -R "$SteamUser:$SteamUser" "$InstanceDir"

	cp -a "$MainConfigTemplate"                                         "$InstanceDir/main.conf"
	cp -a "$DefaultConfigDir/KFAI.ini"                                  "$InstanceDir"
	cp -a "$DefaultConfigDir/KFWeb.ini"                                 "$InstanceDir"
	cp -a "$DefaultConfigDir/LinuxServer-KFEngine.ini"                  "$InstanceDir"
	cp -a "$DefaultConfigDir/LinuxServer-KFGame.ini"                    "$InstanceDir"
	cp -a "$DefaultConfigDir/LinuxServer-KFInput.ini"                   "$InstanceDir"
	cp -a "$DefaultConfigDir/LinuxServer-KFSystemSettings.ini"          "$InstanceDir"
	cp -a "$DefaultConfigDir/LinuxServer/LinuxServerEngine.ini"         "$InstanceDir/LinuxServer"
	cp -a "$DefaultConfigDir/LinuxServer/LinuxServerGame.ini"           "$InstanceDir/LinuxServer"
	cp -a "$DefaultConfigDir/LinuxServer/LinuxServerInput.ini"          "$InstanceDir/LinuxServer"
	cp -a "$DefaultConfigDir/LinuxServer/LinuxServerSystemSettings.ini" "$InstanceDir/LinuxServer"

	echo "Instance $Instance created. See $InstanceDir for edit configuration"
}

function delete_instance () # $1: [InstanceName]
{
	local Instance="$1"
	if [[ -z "$Instance" ]]; then
		echo "Are you sure you want to delete all instances? [y/N]"
		local Answ="N"
		read Answ
		if [[ "$Answ" == "y" || "$Answ" == "Y" ]]; then
			for Instance in $(show_instances)
			do
				stop_instance "$Instance"
				delete_instance "$Instance"
			done
		fi
	elif instance_exists "$Instance"; then
		local InstanceDir="$InstanceConfigDir/$Instance"
		stop_instance "$Instance"
		rm -rf "$InstanceDir"
		echo "Instance $Instance removed"
	else
		echo "Instance $Instance not exists"
	fi
}

function show_status_implementation () # $1: [InstanceName]
{
	local Instance="$1"
	if [[ -n "$Instance" ]]; then
		if systemctl -q is-enabled $(service_name "$Instance"); then
			local IsEnabled="enabled"
		else
			local IsEnabled="disabled"
		fi
		if systemctl | grep $(service_name "$Instance") | grep -q 'running' ; then
			local IsRuning="running"
		else
			local IsRuning="dead"
		fi
		local Description=$(grep -P 'Description=' "$InstanceConfigDir/$Instance/main.conf" | sed -r 's/(Description=|")//g')
		echo -e "$Instance:$IsEnabled:$IsRuning:$Description"
	else
		echo -e "INSTANCE:AUTORUN:STATE:DESCRIPTION"
		for Instance in $(show_instances)
		do
			show_status_implementation "$Instance"
		done
	fi
}

function show_status () # $1: [InstanceName]
{
	show_status_implementation "$1" | column -t -s :
}

function update_kf2 ()
{
	if [[ -n "$BranchName" ]]; then
		local BetaArg="-beta $BranchName"
	fi
	if ! server_exists; then # First install
		chown "root:$SteamUser" "$InstallDir"
		steamcmd +login $SteamLogin +force_install_dir $InstallDir +app_update $AppNum $BetaArg validate +exit
		mkdir "$InstanceConfigDir" && chown "$SteamUser:$SteamUser" "$InstanceConfigDir"
		ln -s "$InstanceConfigDir" "$InstanceConfigLnk"
	elif updates_aviable; then # Update
		stop_instance
		steamcmd +login $SteamLogin +force_install_dir $InstallDir +app_update $AppNum $BetaArg +exit
		start_instance
	fi
}

function start_instance () # $1: [InstanceName]
{
	local Instance="$1"
	if [[ -n "$Instance" ]] ; then
		if instance_exists "$Instance"; then
			systemctl start $(service_name "$Instance")
		else
			echo "Instance $Instance not exitst"
		fi
	else
		for Instance in $(show_instances)
		do
			if systemctl -q is-enabled $(service_name "$Instance") ; then
				start_instance "$Instance"
			fi
		done
	fi
}

function stop_instance () # $1: [InstanceName]
{
	local Instance="$1"
	if [[ -n "$Instance" ]]; then
		if instance_exists "$Instance"; then
			systemctl stop $(service_name "$Instance")
		else
			echo "Instance $Instance not exitst"
		fi
	else
		for Instance in $(show_instances)
		do
			stop_instance "$Instance"
		done
	fi
}

function enable_instance () # $1: [InstanceName]
{
	local Instance="$1"
	if [[ -n "$Instance" ]]; then
		if instance_exists "$Instance"; then
			systemctl enable $(service_name "$Instance")
		else
			echo "Instance $Instance not exitst"
		fi
	else
		for Instance in $(show_instances)
		do
			enable_instance "$Instance"
		done
	fi
}

function disable_instance () # $1: [InstanceName]
{
	local Instance="$1"
	if [[ -n "$Instance" ]]; then
		if instance_exists "$Instance"; then
			systemctl disable $(service_name "$Instance")
		else
			echo "Instance $Instance not exitst"
		fi
	else
		for Instance in $(show_instances)
		do
			disable_instance "$Instance"
		done
	fi
}

function run ()
{
	if [[ "$USER" == "$SteamUser" ]]; then
		"$AppBin" "$@"
	elif [[ -n $(groups "$USER" | grep -Fo 'wheel') ]] || [[ "$EUID" -eq 0 ]]; then
		sudo -u "$SteamUser" "$AppBin" "$@"
	else
		echo "You must be a $SteamUser, root or sudo-user to run this command."
	fi
}

function map_sync ()
{
	# TODO: implementation
	# подсмотреть в скрипте старого серва
	# либо забить хер и перевести всё на steamworkshop
	# последний вариант наверное даже правильнее
	echo "Dummy..."
}

function ban_sync ()
{
	# TODO: implementation
	echo "Dummy..."
}

function map_rotate_save ()
{
	# TODO: implementation
	echo "Dummy..."
}

function map_rotate_load ()
{
	# TODO: implementation
	echo "Dummy..."
}

if [[ $# -eq 0 ]]; then show_help; exit 0; fi
case $1 in
	-h|--help            ) show_help;                                                                 ;;
	-n|--new             ) if [[ "$EUID" -eq 0 ]]; then new_instance     "$2"; else run_as_root $@; fi;;
	-d|--delete          ) if [[ "$EUID" -eq 0 ]]; then delete_instance  "$2"; else run_as_root $@; fi;;
	-l|--list            ) show_instances;                                                            ;;
	-s|--status          ) show_status                                   "$2";                        ;;
	-u|--update          ) if [[ "$EUID" -eq 0 ]]; then update_kf2           ; else run_as_root $@; fi;;
	-r|--run             ) run $@ ;                                                                   ;;
	   --start           ) if [[ "$EUID" -eq 0 ]]; then start_instance   "$2"; else run_as_root $@; fi;;
	   --stop            ) if [[ "$EUID" -eq 0 ]]; then stop_instance    "$2"; else run_as_root $@; fi;;
	   --enable          ) if [[ "$EUID" -eq 0 ]]; then enable_instance  "$2"; else run_as_root $@; fi;;
	   --disable         ) if [[ "$EUID" -eq 0 ]]; then disable_instance "$2"; else run_as_root $@; fi;;
	   --map-sync        ) map_sync;                                                                  ;;
	   --ban-sync        ) ban_sync;                                                                  ;;
	   --map-rotate-save ) map_rotate_save;                                                           ;;
	   --map-rotate-load ) map_rotate_load;                                                           ;;
esac