#!/bin/sh
TEMPLATE_COMMON="iface %s inet %s\n"

TEMPLATE_MAC="    hwaddress ether \$(fw_printenv -n ethaddr || echo 00:00:23:34:45:66)\n"
TEMPLATE_STATIC="    address %s\n    netmask %s\n"

TEMPLATE_WIRELESS="    pre-up wpa_passphrase \"\$(fw_printenv -n wlanssid)\" \"\$(fw_printenv -n wlanpass)\" > /tmp/wpa_supplicant.conf
    pre-up sed -i 's/#psk.*/scan_ssid=1/g' /tmp/wpa_supplicant.conf
    pre-up wpa_supplicant -B -i wlan0 -D nl80211,wext -c /tmp/wpa_supplicant.conf
    post-down killall -q wpa_supplicant
"

show_help() {
	echo "Usage: $0 [OPTIONS]"
	echo "  -i iface       Network interface"
	echo "  -m mode        Mode [dhcp, static]"
	echo "  -h name        Hostname"
	echo
	echo "For wireless interface:"
	echo "  -s SSID        WiFi network SSID"
	echo "  -p password    WiFi passphrase"
	echo
	echo "For static mode:"
	echo "  -a address     Interface IP address"
	echo "  -n netmask     Network mask"
	echo "  -g address     Gateway IP address"
	echo "  -d address     DNS IP address"
	echo
	exit 0
}

while getopts "a:d:g:h:i:m:n:p:s:" flag; do
	case "$flag" in
		a)
			network_address=$OPTARG
			;;

		d)
			network_nameserver=$OPTARG
			;;

		g)
			network_gateway=$OPTARG
			;;

		h)
			network_hostname=$OPTARG
			;;

		i)
			network_interface=$OPTARG
			;;

		m)
			network_mode=$OPTARG
			;;

		n)
			network_netmask=$OPTARG
			;;

		p)
			network_password=$OPTARG
			;;

		s)
			network_ssid=$OPTARG
			;;

		*)
			;;
	esac
done

if [ $# -eq 0 ]; then
	show_help
	exit 1
fi

if [ -z "$network_interface" ]; then
	echo "Network interface is not set"
	exit 1
fi

if [ "$network_interface" = "wlan0" ]; then
	if [ -z "$network_ssid" ]; then
		echo "Wireless network SSID is not set"
		exit 1
	fi

	if [ -z "$network_password" ]; then
		echo "Wireless network passphrase is not set"
		exit 1
	fi
fi

if [ -z "$network_mode" ]; then
	echo "Network mode is not set"
	exit 1
fi

if [ "$network_mode" = "static" ]; then
	if [ -z "$network_address" ]; then
		echo "Interface IP address is not set"
		exit 1
	fi

	if [ -z "$network_netmask" ]; then
		echo "Netmask is not set"
		exit 1
	fi
fi

iface_file="/etc/network/interfaces.d/${network_interface}"
printf "$TEMPLATE_COMMON" $network_interface $network_mode > "$iface_file"

if [ "$network_interface" = "eth0" ]; then
	printf "$TEMPLATE_MAC" >> "$iface_file"
fi

if [ "$network_mode" = "static" ]; then
	printf "$TEMPLATE_STATIC" "$network_address" "$network_netmask" >> "$iface_file"

	if [ -n "$network_gateway" ]; then
		echo "    gateway ${network_gateway}" >> "$iface_file"
	fi

	if [ -n "$network_nameserver" ]; then
		echo "    pre-up echo nameserver ${network_nameserver} > /tmp/resolv.conf" >> "$iface_file"
	fi
fi

if [ "$network_interface" = "wlan0" ]; then
	fw_setenv wlanssid "$network_ssid"
	fw_setenv wlanpass "$network_password"
	printf "$TEMPLATE_WIRELESS" $network_ssid $network_password >> "$iface_file"
fi

if [ -n "$network_hostname" ] && [ "$network_hostname" != "$(hostname)" ]; then
	hostname "$network_hostname"
	echo "$network_hostname" > /etc/hostname
	echo "127.0.0.1 localhost" > /etc/hosts
	echo "127.0.1.1 ${network_hostname}" >> /etc/hosts
fi

exit 0