#!/bin/bash
# LinuxGSM command_monitor.sh module
# Author: Daniel Gibbs
# Contributors: https://linuxgsm.com/contrib
# Website: https://linuxgsm.com
# Description: Monitors server by checking for running processes
# then passes to gamedig and gsquery.

commandname="MONITOR"
commandaction="Monitoring"
moduleselfname="$(basename "$(readlink -f "${BASH_SOURCE[0]}")")"
fn_firstcommand_set

fn_monitor_check_monitoring() {
	if [ -f "${lockdir}/${selfname}.lock" ]; then
		# Part of migration to v23.5.0. #4296
		rm -f "${lockdir:?}/${selfname}.lock"
		date '+%s' > "${lockdir:?}/${selfname}-monitoring.lock"
	elif [ ! -f "${lockdir}/${selfname}-monitoring.lock" ]; then
		# Monitor does not run if lockfile is not found.
		fn_print_dots "Checking lockfile"
		fn_print_checking_eol
		fn_script_log_info "Checking lockfile: CHECKING"
		fn_print_error "Checking lockfile: No lockfile found"
		fn_print_error_eol_nl
		fn_script_log_error "Checking lockfile: No lockfile found: ERROR"
		echo -e "* Start ${selfname} to run monitor."
		core_exit.sh
	fi
}

fn_monitor_check_install() {
	if [ "$(pgrep -fc -u "${USER}" "/bin/bash ./${selfname} install")" != "0" ] || [ "$(pgrep -fcx -u "${USER}" "/bin/bash ./${selfname} i")" != "0" ] || [ "$(pgrep -fcx -u "${USER}" "/bin/bash ./${selfname} auto-install")" != "0" ] || [ "$(pgrep -fcx -u "${USER}" "/bin/bash ./${selfname} ai")" != "0" ]; then
		fn_print_dots "Checking installer"
		fn_print_checking_eol
		fn_script_log_info "Checking installer: CHECKING"
		fn_print_info "Checking installer: LinuxGSM is installing"
		fn_print_info_eol_nl
		fn_script_log_pass "Checking installer: LinuxGSM is installing"
		core_exit.sh
	fi
}

fn_monitor_check_debug() {
	if [ "$(pgrep -fcx -u "${USER}" "/bin/bash ./${selfname} debug")" != "0" ] || [ "$(pgrep -fcx -u "${USER}" "/bin/bash ./${selfname} d")" != "0" ]; then
		fn_print_dots "Checking debug"
		fn_print_checking_eol
		fn_print_info "Checking debug: Debug is running"
		fn_print_info_eol_nl
		fn_script_log_pass "Checking debug: Debug is running"
		core_exit.sh
	fi
}

fn_monitor_check_details() {
	if [ "$(pgrep -fcx -u "${USER}" "/bin/bash ./${selfname} details")" != "0" ] || [ "$(pgrep -fcx -u "${USER}" "/bin/bash ./${selfname} dt")" != "0" ]; then
		fn_print_dots "Checking details"
		fn_print_checking_eol
		fn_print_info "Checking details: Details is running"
		fn_print_info_eol_nl
		fn_script_log_pass "Checking details: Details is running"
		core_exit.sh
	fi
}

fn_monitor_check_starting() {
	# Remove stale lockfile.
	if [ -f "${lockdir}/${selfname}-starting.lock" ]; then
		if [ "$(find "${lockdir}/${selfname}-starting.lock" -mmin +5)" ]; then
			fn_print_dots "Checking start"
			fn_print_checking_eol
			fn_print_warn "Checking start: Removing stale lockfile"
			fn_print_warn_eol_nl
			fn_script_log_warn "Checking start: Removing stale lockfile"
			rm -f "${lockdir:?}/${selfname}-starting.lock"
		fi
	fi

	if [ -f "${lockdir}/${selfname}-starting.lock" ] && [[ "$(pgrep -fcx -u "${USER}" "/bin/bash ./${selfname} start")" != "0" || "$(pgrep -fcx -u "${USER}" "/bin/bash ./${selfname} s")" != "0" ]]; then
		fn_print_dots "Checking start"
		fn_print_checking_eol
		fn_print_info "Checking start: LinuxGSM is starting"
		fn_print_info_eol_nl
		fn_script_log_info "Checking backup: LinuxGSM is starting"
		core_exit.sh
	fi
}

fn_monitor_check_stopping() {
	# Remove stale lockfile.
	if [ -f "${lockdir}/${selfname}-stopping.lock" ]; then
		if [ "$(find "${lockdir}/${selfname}-stopping.lock" -mmin +5)" ]; then
			fn_print_dots "Checking stop"
			fn_print_checking_eol
			fn_print_warn "Checking stop: Removing stale lockfile"
			fn_print_warn_eol_nl
			fn_script_log_warn "Checking stop: Removing stale lockfile"
			rm -f "${lockdir:?}/${selfname}-stopping.lock"
		fi
	fi

	if [ -f "${lockdir}/${selfname}-stopping.lock" ] && [[ "$(pgrep -fcx -u "${USER}" "/bin/bash ./${selfname} stop")" != "0" || "$(pgrep -fcx -u "${USER}" "/bin/bash ./${selfname} s")" != "0" ]]; then
		fn_print_dots "Checking stop"
		fn_print_checking_eol
		fn_print_info "Checking stop: LinuxGSM is stopping"
		fn_print_info_eol_nl
		fn_script_log_info "Checking backup: LinuxGSM is stopping"
		core_exit.sh
	fi
}

fn_monitor_check_restart_request() {
	if [ -f "${lockdir}/${selfname}-restart-request.lock" ]; then
		fn_print_dots "Checking restart: "
		fn_print_checking_eol
		fn_print_info "Checking restart: Restart requested: "
		fn_print_info_eol_nl
		fn_script_log_info "Checking restart: Restart requested"
		check_players_online.sh
		if [ -n "${playersonline}" ]; then
			fn_print_info_nl "${playersonline} players are on the server: restart postponed"
			fn_script_log_info "${playersonline} players are on the server: restart postponed"
			echo "${playersonline}" > "${lockdir:?}/${selfname}-player-numbers.lock"
			date '+%s' > "${lockdir:?}/${selfname}-restart-request.lock"
			core_exit.sh
		fi
		command_restart.sh
		core_exit.sh
	fi
}

fn_monitor_check_backup() {
	# Remove stale lockfile.
	if [ -f "${lockdir}/backup.lock" ]; then
		if [ "$(find "${lockdir}/backup.lock" -mmin +60)" ]; then
			fn_print_dots "Checking backup"
			fn_print_checking_eol
			fn_print_warn "Checking backup: Removing stale lockfile"
			fn_print_warn_eol
			fn_script_log_warn "Checking backup: Removing stale lockfile"
			rm -f "${lockdir:?}/backup.lock"
		fi
	fi

	if [ -f "${lockdir}/backup.lock" ] && [[ "$(pgrep -fcx -u "${USER}" "/bin/bash ./${selfname} backup")" != "0" || "$(pgrep -fcx -u "${USER}" "/bin/bash ./${selfname} b")" != "0" ]]; then
		fn_print_dots "Checking backup"
		fn_print_checking_eol
		fn_print_info "Checking backup: Backup is running"
		fn_print_info_eol_nl
		fn_script_log_info "Checking backup: Backup is running"
		core_exit.sh
	fi
}

fn_monitor_check_update() {
	# Remove stale lockfile.
	if [ -f "${lockdir}/update.lock" ]; then
		if [ "$(find "${lockdir}/update.lock" -mmin +15)" ]; then
			fn_print_dots "Checking update"
			fn_print_checking_eol
			fn_print_warn "Checking update: Removing stale lockfile"
			fn_print_warn_eol_nl
			fn_script_log_warn "Checking update: Removing stale lockfile"
			rm -f "${lockdir:?}/update.lock"
		fi
	fi

	if [ -f "${lockdir}/update.lock" ] && [[ "$(pgrep -fcx -u "${USER}" "/bin/bash ./${selfname} update")" != "0" || "$(pgrep -fcx -u "${USER}" "/bin/bash ./${selfname} validate")" != "0" || "$(pgrep -fcx -u "${USER}" "/bin/bash ./${selfname} v")" != "0" || "$(pgrep -fc force-update "${USER}" "/bin/bash ./${selfname} fu")" != "0" ]]; then
		fn_print_dots "Checking update"
		fn_print_checking_eol
		fn_print_info "Checking update: LinuxGSM is updating the game server"
		fn_print_info_eol_nl
		fn_script_log_pass "Checking update: LinuxGSM is updating the game server"
		core_exit.sh
	fi
}

# Source engine games may display a messages to indicate the server needs restarting.
fn_monitor_check_update_source() {
	if [ -f "${consolelogdir}/${selfname}-console.log" ] && [ "${engine}" == "source" ]; then
		if grep -q "Your server needs to be restarted in order to receive the latest update." "${consolelogdir}/${selfname}-console.log"; then
			fn_print_dots "Checking update"
			fn_print_checking_eol
			fn_script_log_info "Checking update: CHECKING"
			fn_print_ok "Checking update"
			fn_print_ok_eol_nl
			fn_script_log_info "Checking update: ${selfname} has requested a restart for an update to be applied"
			alert="update-restart-request"
			alert.sh
			command_restart.sh
			core_exit.sh
		fi
	fi
}

fn_monitor_check_session() {
	fn_print_dots "Checking session"
	fn_print_checking_eol
	fn_script_log_info "Checking session: CHECKING"
	# Tmux session width and height needs to be reviewed as may no longer be required.
	sessionwidth="80"
	sessionheight="23"
	# Check for PIDS with identical tmux sessions running.
	if [ "$(pgrep -fcx "tmux -L ${socketname} new-session -d -x ${sessionwidth} -y ${sessionheight} -s ${sessionname}")" -ge "2" ]; then
		fn_print_error "Checking session: There are PIDS with identical tmux sessions running"
		fn_print_error_eol_nl
		fn_script_log_error "Checking session: ERROR"
		fn_script_log_error "Checking session: There are PIDS with identical tmux sessions running"
		fn_script_log_error "Checking session: Killing all tmux sessions with the socketname name ${socketname} and session name ${sessionname}"
		pkill -f "tmux -L ${socketname} new-session -d -x ${sessionwidth} -y ${sessionheight} -s ${sessionname}"
		command_restart.sh
		core_exit.sh
	# Check for tmux pids with the same tmux session and socket names. This will reduce issues with migration to release v23.5.0. #4296
	elif [ "$(pgrep -fc -u "${USER}" "tmux -L ${sessionname} new-session -d -x ${sessionwidth} -y ${sessionheight} -s ${sessionname}")" != "0" ]; then
		fn_print_error "Checking session: PIDS with the same tmux session and socket names are running"
		fn_print_error_eol_nl
		fn_script_log_error "Checking session: ERROR"
		fn_script_log_error "Checking session: PIDS with the same tmux session and socket names are running"
		fn_script_log_error "Checking session: Killing session with the socketname name ${sessionname} and session name ${sessionname}"
		pkill -f "tmux -L ${sessionname} new-session -d -x ${sessionwidth} -y ${sessionheight} -s ${sessionname}"
		command_restart.sh
		core_exit.sh
	# Check for tmux pids that are using the old type of tmux session. This will reduce issues with migration to release v23.5.0. #4296
	elif [ "$(pgrep -fc -u "${USER}" "tmux new-session -d -x ${sessionwidth} -y ${sessionheight} -s ${sessionname}")" != "0" ]; then
		fn_print_error "Checking session: PIDS with old type tmux session are running"
		fn_print_error_eol_nl
		fn_script_log_error "Checking session: ERROR"
		fn_script_log_error "Checking session: PIDS with old type tmux session are running"
		fn_script_log_error "Checking session: Killing session with the session name ${sessionname}"
		pkill -f "tmux new-session -d -x ${sessionwidth} -y ${sessionheight} -s ${sessionname}"
		command_restart.sh
		core_exit.sh
	elif [ "${status}" != "0" ]; then
		fn_print_ok "Checking session"
		fn_print_ok_eol_nl
		fn_script_log_pass "Checking session: OK"
		# send LinuxGSM stats if monitor is OK.
		if [ "${stats}" == "on" ] || [ "${stats}" == "y" ] && [ "${querymode}" == "1" ]; then
			info_stats.sh
		fi
	else
		fn_print_error "Checking session"
		fn_print_fail_eol_nl
		fn_script_log_fail "Checking session: FAIL"
		alert="monitor-session"
		alert.sh
		fn_script_log_info "Checking session: Monitor is restarting ${selfname}"
		command_restart.sh
		core_exit.sh
	fi
}

# Monitor will check queryport is set before continuing.
fn_monitor_check_queryport() {
	if [ -z "${queryport}" ] || [ "${queryport}" == "0" ]; then
		fn_print_dots "Checking port"
		fn_print_checking_eol
		fn_script_log_info "Checking port: CHECKING"
		if [ -n "${rconenabled}" ] && [ "${rconenabled}" != "true" ] && [ "${shortname}" == "av" ]; then
			fn_print_warn "Checking port: Unable to query, rcon is not enabled"
			fn_script_log_warn "Checking port: Unable to query, rcon is not enabled"
		else
			fn_print_error "Checking port: Unable to query, queryport is not set"
			fn_script_log_error "Checking port: Unable to query, queryport is not set"
		fi
		core_exit.sh
	fi
}

fn_query_gsquery() {
	if [ ! -f "${modulesdir}/query_gsquery.py" ]; then
		fn_fetch_file_github "lgsm/modules" "query_gsquery.py" "${modulesdir}" "chmodx" "norun" "noforce" "nohash"
	fi
	"${modulesdir}"/query_gsquery.py -a "${queryip}" -p "${queryport}" -e "${querytype}" > /dev/null 2>&1
	querystatus="$?"
}

fn_query_tcp() {
	bash -c "exec 3<> /dev/tcp/'${queryip}'/'${queryport}'" > /dev/null 2>&1
	querystatus="$?"
}

fn_monitor_query() {
	# Will loop and query up to 5 times every 15 seconds.
	# Query will wait up to 60 seconds to confirm server is down as server can become non-responsive during map changes.
	totalseconds=0
	for queryattempt in {1..5}; do
		for queryip in "${queryips[@]}"; do
			fn_print_dots "Querying port: ${querymethod}: ${queryip}:${queryport} : ${totalseconds}/${queryattempt}"
			fn_print_querying_eol
			fn_script_log_info "Querying port: ${querymethod}: ${queryip}:${queryport} : ${queryattempt} : QUERYING"
			# querydelay
			if [ "$(head -n 1 "${lockdir}/${selfname}-started.lock")" -gt "$(date "+%s" -d "${querydelay} mins ago")" ]; then
				fn_print_ok "Querying port: ${querymethod}: ${ip}:${queryport} : ${totalseconds}/${queryattempt}"
				fn_print_delay_eol_nl
				fn_script_log_info "Querying port: ${querymethod}: ${ip}:${queryport} : ${queryattempt} : DELAY"
				fn_script_log_info "Query bypassed: ${gameservername} started less than ${querydelay} minutes ago"
				fn_script_log_info "Server started: $(date -d "@$(head -n 1 "${lockdir}/${selfname}-started.lock")")"
				fn_script_log_info "Current time: $(date)"
				monitorpass=1
				core_exit.sh
			# will use query method selected in fn_monitor_loop
			# gamedig
			elif [ "${querymethod}" == "gamedig" ]; then
				query_gamedig.sh
			# gsquery
			elif [ "${querymethod}" == "gsquery" ]; then
				fn_query_gsquery
			#tcp query
			elif [ "${querymethod}" == "tcp" ]; then
				fn_query_tcp
			fi

			if [ "${querystatus}" == "0" ]; then
				# Server query OK.
				fn_print_ok "Querying port: ${querymethod}: ${queryip}:${queryport} : ${totalseconds}/${queryattempt}"
				fn_print_ok_eol_nl
				fn_script_log_pass "Querying port: ${querymethod}: ${queryip}:${queryport} : ${queryattempt} : OK"
				monitorpass=1
				if [ "${querystatus}" == "0" ]; then
					# Add query data to log.
					if [ "${gdname}" ]; then
						fn_script_log_info "Server name: ${gdname}"
					fi
					if [ "${gdplayers}" ]; then
						fn_script_log_info "Players: ${gdplayers}/${gdmaxplayers}"
					fi
					if [ "${gdbots}" ]; then
						fn_script_log_info "Bots: ${gdbots}"
					fi
					if [ "${gdmap}" ]; then
						fn_script_log_info "Map: ${gdmap}"
					fi
					if [ "${gdgamemode}" ]; then
						fn_script_log_info "Game Mode: ${gdgamemode}"
					fi

					# send LinuxGSM stats if monitor is OK.
					if [ "${stats}" == "on" ] || [ "${stats}" == "y" ]; then
						info_stats.sh
					fi
				fi
				core_exit.sh
			else
				# Server query FAIL.
				fn_print_fail "Querying port: ${querymethod}: ${queryip}:${queryport} : ${totalseconds}/${queryattempt}"
				fn_print_fail_eol
				fn_script_log_warn "Querying port: ${querymethod}: ${queryip}:${queryport} : ${queryattempt} : FAIL"
				# Monitor will try gamedig (if supported) for first 30s then gsquery before restarting.
				# gsquery will fail if longer than 60s
				if [ "${totalseconds}" -ge "59" ]; then
					# Monitor will FAIL if over 60s and trigger gane server reboot.
					fn_print_fail "Querying port: ${querymethod}: ${queryip}:${queryport} : ${totalseconds}/${queryattempt}"
					fn_print_fail_eol_nl
					fn_script_log_warn "Querying port: ${querymethod}: ${queryip}:${queryport} : ${queryattempt} : FAIL"
					# Send alert if enabled.
					alert="monitor-query"
					alert.sh
					command_restart.sh
					fn_firstcommand_reset
					core_exit.sh
				fi
			fi
		done
		# Second counter will wait for 15s before breaking loop.
		for seconds in {1..15}; do
			fn_print_fail "Querying port: ${querymethod}: ${ip}:${queryport} : ${totalseconds}/${queryattempt}"
			fn_print_wait_eol
			fn_sleep_time_1
			totalseconds=$((totalseconds + 1))
			if [ "${seconds}" == "15" ]; then
				break
			fi
		done
	done
}

fn_monitor_loop() {
	# loop though query methods selected by querymode.
	totalseconds=0
	if [ "${querymode}" == "2" ]; then
		local query_methods_array=(gamedig gsquery)
	elif [ "${querymode}" == "3" ]; then
		local query_methods_array=(gamedig)
	elif [ "${querymode}" == "4" ]; then
		local query_methods_array=(gsquery)
	elif [ "${querymode}" == "5" ]; then
		local query_methods_array=(tcp)
	fi
	for querymethod in "${query_methods_array[@]}"; do
		# Will check if gamedig is installed and bypass if not.
		if [ "${querymethod}" == "gamedig" ]; then
			if [ "$(command -v gamedig 2> /dev/null)" ] || [ -f "${lgsmdir}/node_modules/gamedig/bin/gamedig.js" ] && [ "$(command -v jq 2> /dev/null)" ]; then
				if [ -z "${monitorpass}" ]; then
					fn_monitor_query
				fi
			else
				fn_script_log_info "gamedig is not installed"
				fn_script_log_info "https://docs.linuxgsm.com/requirements/gamedig"
			fi
		else
			# will not query if query already passed.
			if [ -z "${monitorpass}" ]; then
				fn_monitor_query
			fi
		fi
	done
}

fn_print_dots ""
monitorflag=1
# Dont do any monitoring or checks if installer is running.
fn_monitor_check_install
check.sh
core_logs.sh
info_game.sh

# query pre-checks
fn_monitor_check_details
fn_monitor_check_backup
fn_monitor_check_debug
fn_monitor_check_update_source
fn_monitor_check_update
fn_monitor_check_monitoring
fn_monitor_check_starting
fn_monitor_check_stopping
fn_monitor_check_session
fn_monitor_check_restart_request

# Monitor will not continue if session only check.
if [ "${querymode}" != "1" ]; then
	fn_monitor_check_queryport

	# Add a querydelay of 1 min if var missing.
	if [ -z "${querydelay}" ]; then
		querydelay="1"
	fi

	fn_monitor_loop
fi

core_exit.sh
