#!/bin/bash
################################################################################
# Copyright 2026 ModalAI Inc.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
#
# 1. Redistributions of source code must retain the above copyright notice,
#    this list of conditions and the following disclaimer.
#
# 2. Redistributions in binary form must reproduce the above copyright notice,
#    this list of conditions and the following disclaimer in the documentation
#    and/or other materials provided with the distribution.
#
# 3. Neither the name of the copyright holder nor the names of its contributors
#    may be used to endorse or promote products derived from this software
#    without specific prior written permission.
#
# 4. The Software is used solely in conjunction with devices provided by
#    ModalAI Inc.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
# POSSIBILITY OF SUCH DAMAGE.
################################################################################

NAME="voxl-static-ip-watcher"
SERVICE_FILE="${NAME}.service"
CONFIG_FILE="/etc/modalai/${NAME}.conf"
NM_CONF_FILE="/etc/NetworkManager/conf.d/99-${NAME}.conf"
SILVUS_UDEV_RULE="/etc/udev/rules.d/70-voxl-silvus.rules"
PILOT_NETWORK_FILE="/etc/systemd/network/20-voxl-dgcs-pilot.network"
TABLET_DHCP_CONF="/etc/dnsmasq.d/90-tablet-dhcp.conf"
DHCP_CLIENT_CONF="/etc/dhcpcd.conf"
USER=$(whoami)


print_usage () {
	echo ""
	echo "Usage:"
	echo "voxl-configure-static-ip-watcher {MODE}"
	echo ""
	echo "Valid Modes are:"
	echo ""
	echo "disable              	     disable the service"
	echo "factory_enable             enable the service, reset config file to defaults"
	echo "factory_enable_dgcs_pilot  configure DGCS pilot Ethernet and DHCP through networkd"
	echo "factory_enable_dgcs_tower  enable the service, configure for DGCS tower"
	echo "factory_enable_dtc_vrx     enable the service, configure for DTC VRX"
	echo "factory_enable_dtc_drone   enable the service, configure for DTC drone"
	echo "factory_enable_silvus_drone  enable the service, configure for Silvus drone"
	echo "factory_enable_silvus_vrx    enable the service, configure for Silvus VRX"
	echo "enable                     enable the service, leave config file alone"
	echo ""
	echo ""
	echo "show this help message:"
	echo "voxl-configure-static-ip-watcher help"
	echo ""
	exit 0
}


## set a top-level parameter (e.g., debug)
set_param () {
	if [ "$#" != "2" ]; then
		echo "set_param expected 2 args"
		exit 1
	fi
	local var="$1"
	local val="$2"
	local tmp=$(mktemp)
	jq ".$var = $val" "${CONFIG_FILE}" > "$tmp" && mv "$tmp" "${CONFIG_FILE}"
}

## set an interface parameter by index
## Args: index, field, value (string)
set_interface_param () {
	if [ "$#" != "3" ]; then
		echo "set_interface_param expected 3 args (index, field, value)"
		exit 1
	fi
	local idx="$1"
	local field="$2"
	local val="$3"
	local tmp=$(mktemp)
	jq ".interfaces[$idx].$field = \"$val\"" "${CONFIG_FILE}" > "$tmp" && mv "$tmp" "${CONFIG_FILE}"
}

## add a new interface entry
## Args: network_interface, static_ip, netmask
add_interface () {
	if [ "$#" != "3" ]; then
		echo "add_interface expected 3 args (network_interface, static_ip, netmask)"
		exit 1
	fi
	local iface="$1"
	local ip="$2"
	local mask="$3"
	local tmp=$(mktemp)
	jq ".interfaces += [{\"network_interface\": \"$iface\", \"static_ip\": \"$ip\", \"netmask\": \"$mask\"}]" \
		"${CONFIG_FILE}" > "$tmp" && mv "$tmp" "${CONFIG_FILE}"
}

## clear all interfaces from config
clear_interfaces () {
	local tmp=$(mktemp)
	jq ".interfaces = []" "${CONFIG_FILE}" > "$tmp" && mv "$tmp" "${CONFIG_FILE}"
}


## keep NetworkManager (QCS6490 images) from running DHCP on interfaces this
## service owns; a failed DHCP attempt deactivates the device and drops the IP
nm_unmanage_interfaces () {
	[ -d /etc/NetworkManager ] || return 0
	mkdir -p "$(dirname "${NM_CONF_FILE}")"
	printf "[keyfile]\nunmanaged-devices=%s\n" "$(printf "interface-name:%s;" "$@")" > "${NM_CONF_FILE}"
	systemctl is-active --quiet NetworkManager && nmcli general reload conf
	return 0
}

nm_release_interfaces () {
	[ -f "${NM_CONF_FILE}" ] || return 0
	rm -f "${NM_CONF_FILE}"
	systemctl is-active --quiet NetworkManager && nmcli general reload conf
	return 0
}

disable_service_and_exit () {
	echo "disabling ${NAME} systemd service"
	systemctl disable ${SERVICE_FILE}
	echo "stopping ${NAME} systemd service"
	systemctl stop ${SERVICE_FILE}
	remove_dgcs_pilot
	nm_release_interfaces
	echo "Done configuring ${NAME}"
	exit 0
}

enable_service_and_exit () {
	if [ -f "${PILOT_NETWORK_FILE}" ]; then
		enable_dgcs_pilot
		exit 0
	fi
	echo "enabling  ${NAME} systemd service"
	systemctl enable  ${SERVICE_FILE}
	echo "Done configuring ${NAME}"
	echo "Service will start on next reboot"
	exit 0
}

reset_config_file_to_default () {
	remove_dgcs_pilot
	nm_release_interfaces
	echo "wiping old config file"
	rm -rf ${CONFIG_FILE}
	${NAME} -c
}

dhcpcd_active () {
	systemctl is-active --quiet dhcpcd.service || systemctl is-active --quiet dhcpcd5.service
}

remove_dgcs_pilot () {
	if [ -f "${PILOT_NETWORK_FILE}" ]; then
		rm -f "${PILOT_NETWORK_FILE}" || exit 1
		if systemctl is-active --quiet systemd-networkd.service; then
			networkctl reload || exit 1
			if [ -e /sys/class/net/eth0 ]; then
				networkctl reconfigure eth0 || exit 1
			fi
		fi
	fi
	if [ -f "${DHCP_CLIENT_CONF}" ] &&
		grep -q '^# BEGIN voxl-dgcs-pilot$' "${DHCP_CLIENT_CONF}"; then
		sed -i '/^# BEGIN voxl-dgcs-pilot$/,/^# END voxl-dgcs-pilot$/d' "${DHCP_CLIENT_CONF}" || exit 1
		if dhcpcd_active && [ -e /sys/class/net/eth0 ]; then
			dhcpcd -n eth0 || exit 1
		fi
	fi
	if [ -e "${TABLET_DHCP_CONF}" ]; then
		rm -f "${TABLET_DHCP_CONF}" || exit 1
		if systemctl is-active --quiet dnsmasq.service; then
			systemctl restart dnsmasq.service || exit 1
		fi
	fi
}

disable_if_present () {
	if [ "$(systemctl show --property=LoadState --value "$1")" = "loaded" ]; then
		systemctl disable --now "$1" || exit 1
	fi
}

enable_dgcs_pilot () {
	if [ "$(systemctl show --property=LoadState --value systemd-networkd.service)" != "loaded" ]; then
		echo "DGCS pilot configuration requires systemd-networkd.service." >&2
		exit 1
	fi
	disable_if_present "${SERVICE_FILE}"
	disable_if_present voxl-static-ip.service
	disable_if_present dnsmasq.service
	rm -f "${TABLET_DHCP_CONF}" || exit 1
	nm_unmanage_interfaces eth0
	if command -v dhcpcd >/dev/null 2>&1; then
		local tmp
		tmp=$(mktemp) || exit 1
		printf '# BEGIN voxl-dgcs-pilot\ndenyinterfaces eth0\n# END voxl-dgcs-pilot\n' > "$tmp"
		if [ -f "${DHCP_CLIENT_CONF}" ]; then
			sed '/^# BEGIN voxl-dgcs-pilot$/,/^# END voxl-dgcs-pilot$/d' "${DHCP_CLIENT_CONF}" >> "$tmp" || exit 1
		fi
		cat "$tmp" > "${DHCP_CLIENT_CONF}" || exit 1
		rm -f "$tmp"
		if dhcpcd_active && [ -e /sys/class/net/eth0 ]; then
			# An already excluded eth0 has no client to release. Other interfaces stay active.
			dhcpcd -k eth0 || true
		fi
	fi
	systemctl enable --now systemd-networkd.service || exit 1
	networkctl reload || exit 1
	if [ -e /sys/class/net/eth0 ]; then
		networkctl reconfigure eth0 || exit 1
	fi
	echo "DGCS pilot Ethernet and DHCP use systemd-networkd."
}

factory_enable_dgcs_pilot () {
	echo "configuring for DGCS pilot"
	if [ "$(systemctl show --property=LoadState --value systemd-networkd.service)" != "loaded" ]; then
		echo "DGCS pilot configuration requires systemd-networkd.service." >&2
		exit 1
	fi
	mkdir -p "$(dirname "${PILOT_NETWORK_FILE}")" || exit 1
	cat > "${PILOT_NETWORK_FILE}" <<'EOF' || exit 1
[Match]
Name=eth0

[Network]
Address=10.0.0.2/24
DHCP=no
LinkLocalAddressing=no
IPv6AcceptRA=no
DHCPServer=yes
ConfigureWithoutCarrier=yes

[DHCPServer]
PoolOffset=1
PoolSize=1
DefaultLeaseTimeSec=1h
MaxLeaseTimeSec=1h
EmitRouter=no
EmitDNS=no
EmitNTP=no
EmitTimezone=no
EOF
	enable_dgcs_pilot
}

factory_enable_dtc_vrx () {
	echo "configuring for DTC VRX"
	reset_config_file_to_default
	clear_interfaces
	add_interface "eth0" "192.168.0.104" "255.255.255.0" # for DTC
	add_interface "eth1" "10.0.0.2" "255.255.255.0"
	set_param "debug" "0"
}

factory_enable_dgcs_tower () {
	echo "configuring for DGCS tower"
	reset_config_file_to_default
	clear_interfaces
	add_interface "eth0" "10.0.0.10" "255.255.255.0"
	set_param "debug" "0"
}

## 172.16.0.0/12 covers every Silvus radio (radio IP = 172.16.0.0 + node id)
factory_enable_silvus_drone () {
	echo "configuring for Silvus drone"
	reset_config_file_to_default
	clear_interfaces
	add_interface "eth0" "172.19.16.10" "255.240.0.0"
	set_param "debug" "0"
}

## the Silvus radio's USB network (RNDIS/Ethernet gadget 0525:a4a2) is bound by cdc_ether
## (eth*) or cdc_subset (usb*) depending on which module loaded first, so pin its name;
## not usb0, the 0.3.x system images create the adb NCM gadget as usb0 when the USB-C
## port comes up in device mode, and whichever appears first takes the name
silvus_udev_rule () {
	cat > "${SILVUS_UDEV_RULE}" <<EOF
# Silvus radio USB network: always silvus0 so ${NAME} can find it
SUBSYSTEM=="net", ACTION=="add", ATTRS{idVendor}=="0525", ATTRS{idProduct}=="a4a2", NAME="silvus0"
EOF
	udevadm control --reload
}

## Silvus radio on silvus0, a USB-Ethernet dongle on eth0 is the developer port at 10.0.0.2,
## the SDK install.sh ssh target
factory_enable_silvus_vrx () {
	echo "configuring for Silvus VRX"
	reset_config_file_to_default
	silvus_udev_rule
	clear_interfaces
	add_interface "silvus0" "172.18.71.10" "255.240.0.0"
	add_interface "eth0" "10.0.0.2" "255.255.255.0"
	set_param "debug" "0"
	nm_unmanage_interfaces "silvus0" "eth0"
}

factory_enable_dtc_drone () {
	echo "configuring for DTC drone"
	reset_config_file_to_default
	clear_interfaces
	add_interface "eth0" "192.168.0.100" "255.255.255.0"
	set_param "debug" "0"
}


################################################################################
## actual start of execution, handle optional arguments first
################################################################################

## sanity checks
if [ "${USER}" != "root" ]; then
	echo "Please run this script as root"
	exit 1
fi

if ! command -v jq >/dev/null 2>&1; then
	echo "jq is required but not found. Please install jq."
	exit 1
fi

## convert argument to lower case for robustness
arg=$(echo "$1" | tr '[:upper:]' '[:lower:]')

## parse arguments
case ${arg} in
	"")
		print_usage
		exit 0
		;;

	"h"|"-h"|"help"|"--help")
		print_usage
		exit 0
		;;

	"disable")
		disable_service_and_exit
		;;

	"factory_enable")
		echo "configuring defaults"
		reset_config_file_to_default
		enable_service_and_exit
		;;

	"factory_enable_dgcs_pilot")
		factory_enable_dgcs_pilot
		exit 0
		;;

	"factory_enable_dgcs_tower")
		factory_enable_dgcs_tower
		enable_service_and_exit
		;;

	"factory_enable_dtc_vrx")
		factory_enable_dtc_vrx
		enable_service_and_exit
		;;
	
	"factory_enable_silvus_drone")
		factory_enable_silvus_drone
		enable_service_and_exit
		;;

	"factory_enable_silvus_vrx")
		factory_enable_silvus_vrx
		enable_service_and_exit
		;;

	"factory_enable_dtc_drone")
		factory_enable_dtc_drone
		enable_service_and_exit
		;;

	"enable")
		enable_service_and_exit
		;;
	*)
		echo "invalid option"
		print_usage
		exit 1
esac



################################################################################
## no option given, print help
################################################################################
print_usage