#!/bin/sh

# In recent (relevant) versions of shellcheck busybox is a valid shell type
# shellcheck shell=busybox

# uci-defaults script to configure sendmail notifications for UPS monitor on
# first boot after installation (if not possible during image creation)
# Expects nut-notify-exec to also be run in uci-defaults.

# IPKG_INSTROOT is intentionally only set when building an image and
# is intentionally empty on a live OpenWrt device

# Shellcheck source paths intentionally point to the location of files of
# the scripts in the development environment (where shellcheck is used), not
# on the live OpenWrt device

# This script lives in the nut-sendmail-notify package, which is independent of
# the nut-upssched package in which nut-sched.default lives.
# In the nut-sendmail-notify package, this script lives in
# /etc/uci-defaults/81-sendmail-notify

# The separate packages limit the opportunities for code-sharing across the
# scripts.

# Only run this uci-defaults script on a live OpenWrt device
[ -z "${IPKG_INSTROOT}" ] || exit 0

# shellcheck source=net/nut/files/functions.sh.functions
. /lib/functions.sh || {
	logger -s -t nut-sendmail-notify "FATAL: Unable to source 'functions.sh'" || true
	exit 1
}

# Flags for existing notifycmd
SKIP_ADD_NOTIFYCMD="false"

# Load and process nut_monitor (upsmon) configuration
config_load nut_monitor || {
	logger -s -t nut-sendmail-notify "FATAL: Loading 'nut_monitor' failed." || true
	exit 1
}

config_get val "upsmon" notifycmd
# shellcheck disable=SC2154
if [ -n "${val}" ]; then
	SKIP_ADD_NOTIFYCMD="true"
fi

# If notification command is not set, set it
if [ "${SKIP_ADD_NOTIFYCMD}" = "false" ]; then
	# Ensure upsmon type section with the name upsmon exists
	uci set "nut_monitor.upsmon=upsmon" || {
		logger -s -t nut-sendmail-notify "Failed to ensure an upsmon section named upsmon exists" || true
		exit 1
	}

	# Only configure notifycmd to be nut-sendmail-notify if sendmail is present
	if [ -n "$(command -v sendmail)" ]; then
		# If nut-upssched (default script nut-sched) is also present, notifycmd will
		# already be set and SKIP_ADD_NOTIFYCMD will be true, so this code will
		# never be reached. This is intentional. upssched takes precedence over
		# nut-sendmail-notify, unless the user writes a script that supports both.
		uci set "nut_monitor.upsmon.notifycmd=/usr/bin/nut-sendmail-notify" || {
			logger -s -t nut-sendmail-notify "Failed to set notifycmd to be nut-sendmail-notify" || true
			uci revert nut_monitor || true
			exit 1
		}
	fi

	uci commit nut_monitor || {
		logger -s -t nut-sendmail-notify "Failed to commit changes to nut_monitor" || true
		exit 1
	}
fi

exit 0