#!/bin/sh /etc/rc.common

START=90

USE_PROCD=1

PROG=/usr/sbin/tailscale_helper
PROGD=/usr/sbin/tailscaled
CONFIG_PATH=/var/lib/tailscale

service_triggers() {
	procd_add_reload_trigger "tailscale"
	procd_add_interface_trigger "interface.*.up" wan /etc/init.d/tailscale reload
}

section_enabled() {
	config_get_bool enabled "$1" 'enabled' 0
	[ $enabled -gt 0 ]
}

tailscale_helper() {
	local cfg="$1"
	local accept_routes hostname accept_dns advertise_exit_node exit_node advertise_routes disable_snat_subnet_routes subnet_routes access flags login_server authkey std_out std_err

	config_get_bool accept_routes $cfg 'accept_routes'
	config_get hostname $cfg 'hostname'
	config_get_bool accept_dns $cfg 'accept_dns'
	config_get_bool advertise_exit_node $cfg 'advertise_exit_node'
	config_get exit_node $cfg 'exit_node'
	config_get advertise_routes $cfg 'advertise_routes'
	config_get_bool disable_snat_subnet_routes $cfg 'disable_snat_subnet_routes'
	config_get subnet_routes $cfg 'subnet_routes'
	config_get access $cfg 'access'
	config_get flags $cfg 'flags'
	config_get login_server $cfg 'login_server'
	config_get authkey $cfg 'authkey'
	config_get_bool std_out $cfg 'log_stdout'
	config_get_bool std_err $cfg 'log_stderr'

	procd_open_instance
	procd_set_param command $PROG

	[ "$accept_routes" = "1" ] && procd_append_param command --accept-routes=true
	[ -n "$hostname" ] && procd_append_param command --hostname="$hostname"
	[ "$accept_dns" = "0" ] && procd_append_param command --accept-dns=false
	[ "$advertise_exit_node" = "1" ] && procd_append_param command --advertise-exit-node
	[ -n "$exit_node" ] && {
		procd_append_param command --exit-node="$exit_node"
		procd_append_param command --exit-node-allow-lan-access=true
	}
	[ -n "$advertise_routes" ] && procd_append_param command --advertise-routes="$(echo $advertise_routes | tr ' ' ',')"
	[ "$disable_snat_subnet_routes" = "1" ] && procd_append_param command --snat-subnet-routes=false
	[ -n "$flags" ] && procd_append_param command $flags
	[ -n "$login_server" ] && procd_append_param command --login-server="$login_server"
	[ -n "$authkey" ] && procd_append_param command --authkey="$authkey"

	procd_set_param env \
		ACCEPT_DNS="$accept_dns" \
		EXIT_NODE="$exit_node" \
		SUBNET_ROUTES="$subnet_routes" \
		ACCESS="$access"

	procd_set_param respawn
	procd_set_param stdout "$std_out"
	procd_set_param stderr "$std_err"
	procd_close_instance
}

start_instance() {
	local cfg="$1"
	local port config_path fw_mode std_out std_err state_file

	if ! section_enabled "$cfg"; then
		echo "disabled in /etc/config/tailscale"
		return 1
	fi

	config_get port $cfg 'port'
	config_get config_path $cfg 'config_path'
	config_get fw_mode $cfg 'fw_mode'
	config_get_bool std_out $cfg 'log_stdout'
	config_get_bool std_err $cfg 'log_stderr'

	[ -d $config_path ] || mkdir -p $config_path
	[ -d $CONFIG_PATH ] || mkdir -p $CONFIG_PATH
	state_file="$config_path/tailscaled.state"
	
	/usr/sbin/tailscaled --cleanup

	procd_open_instance
	procd_set_param command $PROGD

	[ -n "$port" ] && procd_append_param command --port "$port"
	[ -n "$state_file" ] && procd_append_param command --state "$state_file"

	procd_set_param env TS_DEBUG_FIREWALL_MODE="$fw_mode"
	
	procd_set_param respawn
	procd_set_param stdout "$std_out"
	procd_set_param stderr "$std_err"
	procd_close_instance

	tailscale_helper "$cfg"
}

start_service() {
	config_load 'tailscale'
	config_foreach start_instance 'tailscale'
}

stop_instance() {
	local cfg="$1"

	# Remove dnsmasq settings
	MagicDNSSuffix=$(tailscale status --json | awk -F'"' '/"MagicDNSSuffix"/ {last=$(NF-1)} END {print last}')
	for suffix in $(uci show dhcp | grep -E "address=.*/${MagicDNSSuffix}/" | sed "s/'//g"); do
		uci -q del_list $suffix
	done
 
	# Remove network settings
	uci -q delete network.tailscale
	uci -q delete network.ts_lan
	for route in $(uci show network | grep 'network.ts_subnet[0-9]\+=route' | grep -o 'network.ts_subnet[0-9]\+'); do
		uci -q delete $route
	done
	
	# Remove firewall settings
	index=$(uci show firewall | grep "firewall.@forwarding\[[0-9]\+\]\.src='lan'" -B 1 -A 1 | grep "firewall.@forwarding\[[0-9]\+\]\.dest='wan'" | grep -o '[0-9]\+')
	uci -q delete firewall.@forwarding[$index].enabled
	uci -q delete firewall.tszone
	uci -q delete firewall.ts_ac_lan
	uci -q delete firewall.ts_ac_wan
	uci -q delete firewall.lan_ac_ts
	uci -q delete firewall.wan_ac_ts
	
	# Commit configuration changes and reload service
	[ -n "$(uci changes dhcp)" ] && uci commit dhcp && /etc/init.d/dnsmasq reload
	[ -n "$(uci changes network)" ] && uci commit network && /etc/init.d/network reload
	[ -n "$(uci changes firewall)" ] && uci commit firewall && /etc/init.d/firewall reload

	/usr/sbin/tailscaled --cleanup

	# Remove existing link or folder
	rm -rf "$CONFIG_PATH"
}

stop_service() {
	config_load 'tailscale'
	config_foreach stop_instance 'tailscale'
}

reload_service() {
	stop
	start
}