#!/bin/sh -e
#
#    wifi_quality: display wifi signal quality
#
#    Copyright (C) 2008 Canonical Ltd.
#    Copyright (C) 2011-2014 Dustin Kirkland
#
#    Authors: Dustin Kirkland <kirkland@byobu.org>
#
#    This program is free software: you can redistribute it and/or modify
#    it under the terms of the GNU General Public License as published by
#    the Free Software Foundation, version 3 of the License.
#
#    This program is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#    GNU General Public License for more details.
#
#    You should have received a copy of the GNU General Public License
#    along with this program.  If not, see <http://www.gnu.org/licenses/>.

___get_dev_list() {
	if [ -n "$MONITORED_NETWORK" ]; then
		echo "$MONITORED_NETWORK"
	elif [ "$BYOBU_OSTYPE" = "OpenBSD" ]; then
		# OpenBSD: list wireless interfaces by known driver prefixes.
		# Update this list when new wireless drivers are added to OpenBSD.
		# See: man 4 iwx, man 4 iwm, etc. in the OpenBSD kernel source.
		for _if in $(ifconfig 2>/dev/null | grep '^[a-z]' | cut -d: -f1); do
			case "$_if" in
				iwn*|iwm*|iwx*|athn*|ath*|rum*|run*|urtwn*|rtwn*) echo "$_if" ;;
			esac
		done
	else
		iw dev | grep Interface | cut -f2 -d\ 
	fi
}

__wifi_quality_detail() {
	if eval $BYOBU_TEST iw >/dev/null 2>&1; then
		local dev
		for dev in $(___get_dev_list); do
			iw dev "$dev" info
			iw dev "$dev" link
			echo
		done
	elif eval $BYOBU_TEST iwconfig >/dev/null 2>&1; then
		iwconfig 2>/dev/null
	fi
}

__wifi_quality() {
	local out bitrate quality
	# OpenBSD: parse ifconfig for signal strength
	if [ "$BYOBU_OSTYPE" = "OpenBSD" ]; then
		local dev sig
		for dev in $(___get_dev_list); do
			sig=$(ifconfig "$dev" 2>/dev/null | awk '/ [0-9-]+dBm/ { for(i=1;i<=NF;i++) if ($i ~ /dBm$/) { gsub(/dBm/,"",$i); print $i; exit } }')
			if [ -n "$sig" ]; then
				# Convert dBm to quality percentage
				quality=$(( (sig + 110) * 100 / 70 ))
				[ "$quality" -gt 100 ] && quality=100
				[ "$quality" -lt 0 ] && quality=0
				bitrate=$(ifconfig "$dev" 2>/dev/null | awk '/media:.*Mb/ { for(i=1;i<=NF;i++) if ($i ~ /Mb/) { gsub(/Mb.*/,"",$i); print $i; exit } }')
				[ -n "$bitrate" ] || bitrate=0
				break
			fi
		done
	fi
	if [ -z "$quality" ] && eval $BYOBU_TEST iwconfig >/dev/null 2>&1; then
		# iwconfig is expected to output lines like:
		#    Bit Rate=54 Mb/s   Tx-Power=15 dBm
		#    Link Quality=60/70  Signal level=-50 dBm
		# the awk below tokenizes the output and prints shell evalable results
		out=`iwconfig "$MONITORED_NETWORK" 2>/dev/null |
			awk '$0 ~ /[ ]*Link Quality./ {
			    sub(/.*=/,"",$2); split($2,a,"/");
			    printf "quality=%.0f\n", 100*a[1]/a[2] };
			    $0 ~ /[ ]*Bit Rate/ { sub(/.*[:=]/,"",$2); printf("bitrate=%.1f\n", $2+0); }
			    '`
		eval "$out"
	elif eval $BYOBU_TEST iw >/dev/null 2>&1; then
		local dev
		for dev in $(___get_dev_list); do
			# iw is expected to output lines like:
			#     signal: -50 dBm
			#     rx bitrate: 216.0 MBit/s MCS 13 40MHz
			# signal to quality: https://superuser.com/a/1360447
			out=`iw dev "$dev" link 2>/dev/null |
				awk '$0 ~ /^\s*signal:/ { a = 100 * ($2 + 110) / 70;
				    printf "quality=%.0f\n", (a > 100) ? 100 : ((a < 0) ? 0 : a); }
				    $0 ~ /^\s*rx bitrate:/ { printf "bitrate=%.1f\n", $3+0; }
				    '`
			eval "$out"
			[ -z "$bitrate" ] || [ -z "$quality" ] || break
		done
	fi
	[ -n "$bitrate" ] || bitrate=0
	[ -n "$quality" ] || quality=0
	if [ "$bitrate" -gt 0 ] && [ "$quality" -gt 0 ]; then
		printf "${ICON_WIFI}"; color b C k; printf "%s" "$bitrate"; color -; color C k; printf "%s" "$ICON_MBPS"; color -; color b C k; printf "%s" "$quality"; color -; color C k; printf "%s" "$PCT"; color --
	else
		rm -f "$BYOBU_RUN_DIR/status.$BYOBU_BACKEND/wifi_quality"*
	fi
}

# vi: syntax=sh ts=4 noexpandtab
