#!/bin/sh /etc/rc.common
# Copyright © 2012 OpenWrt.org
#
# This is free software, licensed under the GNU General Public License v2.
# See /LICENSE for more information.
#

# shellcheck shell=ash

# shellcheck disable=SC2034
START=70
STOP=30

USERS_C=/var/etc/nut/upsd.users
UPSD_C=/var/etc/nut/upsd.conf
UPS_C=/var/etc/nut/ups.conf

USE_PROCD=1

get_write_ups_config() {
	local ups="$1"
	local var="$2"
	local def="$3"
	local flag="$4"
	local val

	[ -z "$flag" ] && {
		config_get val "$ups" "$var" "$def"
		[ -n "$val" ] && [ "$val" != "0" ] && echo "$var = $val" >>"$UPS_C"
	}

	[ -n "$flag" ] && {
		config_get_bool val "$ups" "$var" "$def"
		[ "$val" = 1 ] && echo "$var" >>"$UPS_C"
	}
}

srv_statepath() {
	local statepath

	config_get statepath upsd statepath /var/run/nut
	STATEPATH="$statepath"
}

srv_runas() {
	local runas

	[ -n "$RUNAS" ] && return 0

	config_get runas upsd runas nut
	RUNAS="$runas"
}

listen_address() {
	local srv="$1"

	config_get address "$srv" address "::1"
	config_get port "$srv" port
	# shellcheck disable=SC2154
	echo "LISTEN $address $port" >>"$UPSD_C"
}

srv_config() {
	local srv="$1"
	local maxage maxconn certfile runas statepath

	# Note runas support requires you make sure USB device file is readable by
	# the runas user
	config_get runas "$srv" runas nut
	RUNAS="$runas"

	config_get statepath "$srv" statepath /var/run/nut
	STATEPATH="$statepath"

	config_get maxage "$srv" maxage
	[ -n "$maxage" ] && echo "MAXAGE $maxage" >>"$UPSD_C"

	[ -n "$statepath" ] && echo "STATEPATH $statepath" >>"$UPSD_C"

	config_get maxconn "$srv" maxconn
	[ -n "$maxconn" ] && echo "MAXCONN $maxconn" >>"$UPSD_C"

	#NOTE: certs only apply to SSL-enabled version
	config_get certfile "$srv" certfile
	[ -n "$certfile" ] && echo "CERTFILE $certfile" >>"$UPSD_C"
}

nut_user_add() {
	local user="$1"
	local a
	local val

	config_get val "$user" username "$1"
	echo "[$val]" >> "$USERS_C"

	config_get val "$user" password
	echo "  password = $val" >> "$USERS_C"

	config_get val "$user" actions
	for a in $val; do
		echo "  actions = $a" >> "$USERS_C"
	done

	instcmd() {
		# shellcheck disable=2317
		local val="$1"
		# shellcheck disable=2317
		echo "  instcmds = $val" >> "$USERS_C"
	}

	config_list_foreach "$user" instcmd instcmd

	config_get val "$user" upsmon
	if [ -n "$val" ]; then
		echo "  upsmon $val" >> "$USERS_C"
	fi
}

build_server_config() {
	mkdir -p "$(dirname "$UPSD_C")"
	chmod 0640 "$UPS_C"
	rm -f "$USERS_C"
	rm -f "$UPSD_C"
	rm -f /var/etc/nut/nut.conf

	echo "# Config file automatically generated from UCI config" > "$USERS_C"
	echo "# Config file automatically generated from UCI config" > "$UPSD_C"

	config_foreach nut_user_add user
	config_foreach listen_address listen_address
	config_foreach srv_config upsd
	echo "MODE=netserver" >>/var/etc/nut/nut.conf

	chmod 0640 "$USERS_C"
	chmod 0640 "$UPSD_C"
	chmod 0644 /var/etc/nut/nut.conf

	if [ -n "$RUNAS" ]; then
		chgrp "$(id -gn "$RUNAS")" "$USERS_C"
		chgrp "$(id -gn "$RUNAS")" "$UPSD_C"
	fi
	havesrvcfg=1
}

build_ups_config() {
	local ups="$1"

	echo "[$ups]" >>"$UPS_C"

	get_write_ups_config "$ups" bus
	get_write_ups_config "$ups" cable
	get_write_ups_config "$ups" community
	get_write_ups_config "$ups" desc
	get_write_ups_config "$ups" driver "usbhid-ups"
	get_write_ups_config "$ups" ignorelb 0 1
	get_write_ups_config "$ups" interruptonly 0 1
	get_write_ups_config "$ups" interruptsize
	get_write_ups_config "$ups" maxreport
	get_write_ups_config "$ups" maxstartdelay
	get_write_ups_config "$ups" mfr
	get_write_ups_config "$ups" model
	get_write_ups_config "$ups" nolock 0 1
	get_write_ups_config "$ups" notransferoids 0 1
	get_write_ups_config "$ups" offdelay
	get_write_ups_config "$ups" ondelay
	get_write_ups_config "$ups" pollfreq
	get_write_ups_config "$ups" port "auto"
	get_write_ups_config "$ups" product
	get_write_ups_config "$ups" productid
	get_write_ups_config "$ups" retrydelay
	get_write_ups_config "$ups" sdorder
	get_write_ups_config "$ups" sdtime
	get_write_ups_config "$ups" serial
	get_write_ups_config "$ups" shutdown_delay
	get_write_ups_config "$ups" snmp_version
	get_write_ups_config "$ups" snmp_retries
	get_write_ups_config "$ups" snmp_timeout
	get_write_ups_config "$ups" synchronous
	get_write_ups_config "$ups" usd
	get_write_ups_config "$ups" vendor
	get_write_ups_config "$ups" vendorid

	# Params specific to NetXML driver
	get_write_ups_config "$ups" login
	get_write_ups_config "$ups" password
	get_write_ups_config "$ups" subscribe 0 1

	# shellcheck disable=SC2317
	defoverride() {
		local overvar="$1"
		local defover="$2"
		local overtype
		local overval

		overtype="$(echo "$overvar" | tr '_' '.')"

		config_get overval "${defover}_${overvar}" value
		[ -n "$overval" ] && echo "${defover}.${overtype} = $overval" >>"$UPS_C"
	}

	config_list_foreach "$ups" override defoverride override
	config_list_foreach "$ups" default defoverride default

	other() {
		# shellcheck disable=SC2317
		local othervar="$1"
		# shellcheck disable=SC2317
		local othervarflag="$2"
		# shellcheck disable=SC2317
		local otherval

		# shellcheck disable=SC2317
		if [ "$othervarflag" = "otherflag" ]; then
			config_get_bool otherval "${othervarflag}_${othervar}" value
			[ "$otherval" = "1" ] && echo "${othervar}" >>"$UPS_C"
		else
			config_get otherval "${othervarflag}_${othervar}" value
			[ -n "$otherval" ] && echo "${othervar} = $otherval" >>"$UPS_C"
		fi
	}

	config_list_foreach "$ups" other other other
	config_list_foreach "$ups" otherflag other otherflag
	echo "" >>$UPS_C
	haveupscfg=1
}

build_global_driver_config() {
	local cfg="$1"

	# Global driver config
	get_write_ups_config "$cfg" chroot
	get_write_ups_config "$cfg" driverpath
	get_write_ups_config "$cfg" maxstartdelay
	get_write_ups_config "$cfg" maxretry
	get_write_ups_config "$cfg" retrydelay
	get_write_ups_config "$cfg" pollinterval
	get_write_ups_config "$cfg" synchronous
	config_get runas "$cfg" user nut
	RUNAS="$runas"

	echo "" >>"$UPS_C"
}

build_config() {
	local STATEPATH=/var/run/nut

	mkdir -p "$(dirname "$UPS_C")"
	rm -f "$UPS_C"
	echo "# Config file automatically generated from UCI config" > "$UPS_C"
	chmod 0640 "$UPS_C"

	config_load nut_server

	srv_runas
	srv_statepath

	[ -d "${STATEPATH}" ] || {
		mkdir -p "${STATEPATH}"
	}
	chmod 0770 "${STATEPATH}"

	if [ -n "$RUNAS" ]; then
		chown root:"$(id -gn "$RUNAS")" "${STATEPATH}"
	fi

	SRV_RUNAS="$RUNAS"
	config_foreach build_global_driver_config driver_global
	if [ "$SRV_RUNAS" != "$RUNAS" ]; then
		echo "WARNING: for proper communication drivers and server must 'runas' the same user" | logger -t nut-server
	fi

	config_foreach build_ups_config driver

	build_server_config
	[ -n "$RUNAS" ] && chgrp "$(id -gn "$RUNAS")" "$UPS_C"
}

ensure_usb_ups_access() {
	local ups="$1"
	local vendorid
	local productid
	local runas=nut

	runas="$RUNAS"

	config_load nut_server
	config_get vendorid "$ups" vendorid
	config_get productid "$ups" productid
	config_get serial "$ups" serial

	[ -n "$vendorid" ] || return
	[ -n "$productid" ] || return

	local NL='
'

	find /sys/devices -name idVendor -a -path '*usb*'| while IFS="$NL" read -r vendor_path; do
			local usb_bus usb_dev device_path

			# Filter by vendor ID first
			if [ "$(cat "$vendor_path" 2>/dev/null)" != "$vendorid" ]; then
				continue
			fi

			device_path="$(dirname "$vendor_path")"

			# Then filter by product ID
			if [ "$(cat "$device_path/idProduct" 2>/dev/null)" != "$productid" ]; then
				continue
			fi

			# Next filter by serial, if provided
			if [ -n "$serial" ] && [ "$serial" != "$(cat "$device_path"/serial)" ]; then
				continue
			fi

			usb_bus="$(printf "%03d" "$(cat "$device_path"/busnum)")"
			usb_dev="$(printf "%03d" "$(cat "$device_path"/devnum)")"

			# usb_bus and usb_dev must each be at least 001
			# a missing value will be present as 000 due to 'printf "%03d"'
			local MISSING_USB_NUM="000"
			if [ "$usb_bus" != "$MISSING_USB_NUM" ] && [ "$usb_dev" != "$MISSING_USB_NUM" ]; then
				chmod 0660 /dev/bus/usb/"$usb_bus"/"$usb_dev"
				chown "${runas:-root}":"$(id -gn "${runas:-root}")" /dev/bus/usb/"$usb_bus"/"$usb_dev"
			fi

			# Serial numbers are defined as unique, so do not loop further if serial
			# was present and matched
			if [ -n "$serial" ]; then
				break
				# If a serial number is not provided we need all vendor:product matches
				# to have permissions for NUT as we do not know the matching method here
			fi
		done
}

# Must be called from start_service
start_ups_driver() {
	local ups="$1"
	local requested="$2"
	local driver
	local STATEPATH=/var/run/nut
	local RUNAS=nut

	# If wanting a specific instance, only start it
	if [ "$requested" != "$ups" ] && [ "$requested" != "" ]; then
		return 0
	fi

	# Avoid hotplug inadvertently restarting driver during
	# forced shutdown
	[ -f /var/run/killpower ] && return 0
	if [ -d /var/run/nut ] && [ -f /var/run/nut/disable-hotplug ]; then
		return 0
	fi

	# Depends on config_load from start_service
	srv_statepath
	srv_runas
	ensure_usb_ups_access "$ups"

	config_get driver "$ups" driver "usbhid-ups"
	procd_open_instance "$ups"
	procd_set_param respawn
	procd_set_param stderr 1
	procd_set_param stdout 0 # Subset of stderr
	procd_set_param env NUT_QUIET_INIT_UPSNOTIFY=true
	procd_set_param env NUT_STATEPATH="${STATEPATH}"
	procd_set_param command /lib/nut/"${driver}" -FF -a "$ups" ${RUNAS:+-u "$RUNAS"}
	procd_close_instance
	haveupscfg=1
}

interface_triggers() {
	local action="$1"
	local triggerlist trigger

	config_get triggerlist upsd triggerlist

	# shellcheck disable=SC1091
	. /lib/functions/network.sh

	if [ -n "$triggerlist" ]; then
		for trigger in $triggerlist; do
			if [ "$action" = "add_trigger" ]; then
				procd_add_interface_trigger "interface.*" "$trigger" /etc/init.d/nut-server reload
			else
				network_is_up "$trigger" && return 0
			fi
		done
	else
		if [ "$action" = "add_trigger" ]; then
			procd_add_raw_trigger "interface.*.up" 2000 /etc/init.d/nut-server reload
		else
			ubus call network.device status | grep -q '"up": true' && return 0
		fi
	fi
	[ "$action" = "add_trigger" ] || return 1
}

start_server_instance() {
	local srv="$1"

	procd_open_instance "$srv"
	procd_set_param respawn
	procd_set_param stderr 1
	procd_set_param stdout 0 # Subset of stderr
	procd_set_param env NUT_QUIET_INIT_UPSNOTIFY=true
	procd_set_param env NUT_STATEPATH="$STATEPATH"
	procd_set_param command /usr/sbin/upsd -FF ${RUNAS:+-u "$RUNAS"}
	procd_close_instance
}

# shellcheck disable=SC2120
start_service() {
	local STATEPATH=/var/run/nut
	local haveupscfg=0
	local havesrvcfg=0

	# Avoid hotplug inadvertently restarting driver during
	# forced shutdown
	[ -f /var/run/killpower ] && return 0

	srv_statepath
	config_load nut_server
	build_config

	should_start_srv=1
	[ "$havesrvcfg" = "1" ] || should_start_srv=0
	# Avoid crashloop on server (upsd) when no ups is configured; make sure server
	# is not running if no ups is found in configuration
	[ "$haveupscfg" = "1" ] || should_start_srv=0
	interface_triggers "check_interface_up" || should_start_srv=0

	[ "$should_start_srv" = "1" ] || return 0

	# We only start one service (upsd or one driver) from a given invocation
	case "$1" in
	"")
		config_foreach start_ups_driver driver
		start_server_instance upsd
		;;
	*upsd*)
		start_server_instance upsd
		;;
	*)
		config_foreach start_ups_driver driver "$1"
		;;
	esac
}

server_active() {
	local nut_server_active

	nut_server_active=$(_procd_ubus_call list | jsonfilter -l 1 -e "@['nut-server']")
	[ "$nut_server_active" = "{ }" ] && return 0
}

list_running_instances() {
	local service="$1"
	local running_instances

	running_instances=$(_procd_ubus_call list | jsonfilter -e "@['$service'][@.*.running=true]")

	if [ -n "$running_instances" ]; then
		json_init
		json_load "$running_instances"
		json_get_keys instance_names
		# shellcheck disable=SC2154
		echo "$instance_names"
		json_cleanup
	fi
}

signal_instance() {
	local instance_name="$1"
	local process_name="$2"
	local signal_command="$3"
	local signal="$4"
	local pidfile="$5"
	local secondary_command="$6"

	if [ -s "$pidfile" ]; then
		$signal_command | logger -t nut-server
	elif pgrep "$process_name" >/dev/null 2>/dev/null; then
		procd_send_signal nut-server "$instance_name" "$signal" 2>&1 | logger -t nut-server
	fi
	if [ -n "$secondary_command" ] && procd_running nut-server "$instance_name"; then
		$secondary_command 2>&1 | logger -t nut-server
	fi
}

stop_ups_driver() {
	local ups="$1" # The ups (driver instance)
	local requested="$2"
	local driver

	# If wanting a specific instance, only stop it
	if [ "$requested" != "$ups" ] && [ "$requested" != "" ]; then
		return 0
	fi

	srv_statepath
	build_ups_config "$ups"

	# If we don't have UPS configuration simply stop all instances
	if [ "$haveupscfg" != "1" ]; then
		if procd_running nut-server '*' >/dev/null 2>&1; then
			procd_kill nut-server '*' 2>&1 | logger -t nut-server
		fi
		return 0
	fi

	config_get driver "$ups" driver "usbhid-ups"

	if procd_running nut-server "$ups"; then
		signal_instance "$ups" "$driver" "/lib/nut/'${driver}' -c exit -a '${ups}'" "TERM" "${STATEPATH}/${driver}-${ups}.pid"
		if procd_running nut-server upsd >/dev/null 2>&1; then
			signal_instance upsd upsd "upsd -c stop" "TERM" "${STATEPATH}/upsd.pid" "procd_kill nut-server upsd"
		fi
	fi
}

reload_ups_driver() {
	local ups="$1"
	local requested="$2"
	local driver

	# If wanting a specific instance, only reload that instance
	if [ "$requested" != "$ups" ] && [ "$requested" != "" ]; then
		return 0
	fi

	# Avoid hotplug inadvertently restarting driver during
	# forced shutdown
	[ -f /var/run/killpower ] && return 0
	if [ -d /var/run/nut ] && [ -f /var/run/nut/disable-hotplug ]; then
		return 0
	fi

	config_get driver "$ups" driver "usbhid-ups"

	srv_statepath

	# Try to reload, otherwise exit politely, then stop and restart procd instance
	if procd_running nut-server "$ups"; then
		signal_instance "$ups" "$driver" "/lib/nut/'${driver}' -c reload-or-exit -a '${ups}'" HUP "${STATEPATH}/${driver}-${ups}.pid"
	fi
	/etc/init.d/nut-server start "$ups" 2>&1 | logger -t nut-server
}

reload_service() {
	local should_stop_srv
	local STATEPATH=/var/run/nut
	local havesrvcfg=0
	local haveupscfg=0
	local running_instances
	local driver

	# Avoid hotplug inadvertently restarting driver during forced shutdown
	[ -f /var/run/killpower ] && return 0

	config_load nut_server
	build_config

	should_stop_srv=0
	[ "$havesrvcfg" = "1" ] || should_stop_srv=1
	# Avoid crashloop on server (upsd) when no ups is configured; make sure server
	# is not running if no ups is found in configuration
	[ "$haveupscfg" = "1" ] || should_stop_srv=1
	interface_triggers "check_interface_up" || should_stop_srv=1

	if [ "$should_stop_srv" != "0" ]; then
		if procd_running nut-server upsd >/dev/null 2>&1; then
			procd_kill nut-server upsd 2>&1 | logger -t nut-server
		fi
		config_foreach stop_ups_driver driver

		# Also stop any driver instances which are no longer configured
		for instance in $(list_running_instances "nut-server"); do
			if [ "$instance" != "upsd" ] && procd_running nut-server "$instance" >/dev/null 2>&1; then
				procd_kill nut-server "$instance" 2>&1 | logger -t nut-server
			fi
		done
	fi

	# If nut-server was started but has no instances (even upsd)
	if server_active; then
		logger -t nut-server "nut-server active with no instances"
		/etc/init.d/nut-server start 2>&1 | logger -t nut-server
	# Otherwise, if we have at least one instance running
	elif procd_running nut-server; then
		# If server (upsd) is running
		if procd_running nut-server upsd; then
			# Try to signal server (upsd) to reload configuration
			signal_instance "upsd" "upsd" "upsd -c reload" HUP "${STATEPATH}/upsd.pid"
		# If server (upsd) is not running
		else
			# Start server (upsd)
			/etc/init.d/nut-server start "upsd" 2>&1 | logger -t nut-server
		fi
		config_foreach reload_ups_driver driver

		# Stop any driver instances which are no longer configured
		# We can only reliably do this for instances managed by procd
		for instance in $(list_running_instances "nut-server"); do
			if [ "$instance" = "upsd" ]; then
				continue
			fi
			unset driver
			config_get driver "$instance" driver
			if [ -z "$driver" ] && procd_running nut-server "$instance" >/dev/null 2>&1; then
				procd_kill nut-server "$instance" 2>&1 | logger -t nut-server
			fi
		done
	# Nut-server is not started, so start it
	else
		/etc/init.d/nut-server start 2>&1 | logger -t nut-server
	fi
}

stop_service() {
	config_load nut_server
	srv_statepath

	# We only handle the first parameter passed
	case "$1" in
	"")
		# If nut-server was started but has no instances (even upsd)
		if server_active; then
			logger -t nut-server "nut-server active with no instances"
			procd_kill nut-server 2>&1 | logger -t nut-server
		elif procd_running nut-server; then # if have at least one instance
			signal_instance "upsd" "upsd" "upsd -c stop" TERM "${STATEPATH}/upsd.pid" "procd_kill nut-server upsd"

			config_foreach stop_ups_driver driver

			# Also stop any driver instances which are no longer configured
			for instance in $(list_running_instances "nut-server"); do
				if [ "$instance" != "upsd" ] && procd_running nut-server "$instance" >/dev/null 2>&1; then
					procd_kill nut-server "$instance" 2>&1 | logger -t nut-server
				fi
			done

			# If nut-server active but has no instances (even upsd)
			if server_active >/dev/null 2>&1; then
				procd_kill nut-server 2>&1 | logger -t nut-server
			fi
		fi
		;;
	*upsd*)
		if procd_running nut-server upsd; then
			signal_instance "upsd" "upsd" "upsd -c stop" TERM "${STATEPATH}/upsd.pid" "procd_kill nut-server upsd"
			# If nut-server is active with no instances
			if server_active; then
				procd_kill nut-server 2>&1 | logger -t nut-server
			fi
		fi
		;;
	*)
		# We only handle the first parameter, so do not pass in all parameters
		config_foreach stop_ups_driver driver "$1"
		;;
	esac
}

service_triggers() {
	config_load nut_server

	interface_triggers "add_trigger"
	procd_add_reload_trigger "nut_server"
}