#!/usr/bin/env mksh
# Script by Ypnose - http://ywstd.fr

W_SCR="${0##*/}"
W_INF="wlo1"
W_NNS="1"

function p_err {
	print -u2 -- "$1"
	exit 1
}

function usage {
	print "usage: $W_SCR [-d] [-f WPA_FILE] [-h] [-i INTERFACE] [-n] [-r] [-s]"
	exit
}

function chk_inf {
	if ! ip -br link show "$W_INF" >/dev/null 2>&1; then
		p_err "$W_INF does not exist"
	fi
}

function get_con {
	if [[ -z $W_CON ]]; then
		p_err "wpa_supplicant configuration file is not specified"
	elif [[ ! -r $W_CON ]]; then
		p_err "$W_CON is missing or not readable"
	fi
	chk_inf
	if pgrep -f "wpa_supplicant -i $W_INF" >/dev/null 2>&1; then
		p_err "wpa_supplicant already running for $W_INF"
	fi
	ip link set dev "$W_INF" up
	wpa_supplicant -i "$W_INF" -B -c "$W_CON"
	if (( W_NIP != 1 )); then
		dhcpcd ${W_NNS:+-C resolv.conf} -C wpa_supplicant -w "$W_INF"
	fi
}

function end_con {
	chk_inf
	dhcpcd -x "$W_INF"
	# Make sure addresses are purged
	ip addr flush dev "$W_INF"
	pkill -f "wpa_supplicant -i $W_INF"
	ip link set dev "$W_INF" down
}

trap 'end_con' INT TERM

if [[ $1 = "-h" ]]; then
	usage
fi

if (( USER_ID != 0 )); then
	p_err "${0##*/} must be run as root"
fi

while getopts "df:i:nrs" arg; do
	case "$arg" in
		d) W_DIS="1"       ;;
		f) W_CON="$OPTARG" ;;
		i) W_INF="$OPTARG" ;;
		n) W_NIP="1"       ;;
		r) W_RES="1"       ;;
		s) unset W_NNS     ;;
		*) usage           ;;
	esac
done
shift $(( OPTIND - 1 ))

if (( $# != 0 )); then
	usage
fi

if (( W_RES == 1 )); then
	end_con
	sleep 3
	get_con
elif (( W_DIS == 1 )); then
	end_con
else
	get_con
fi

exit