#!/bin/sh -efu


set -efu


cd /root/files/wifi-tracker || exit 1


export "PATH=$PATH:/usr/local/sbin:/usr/local/bin"


match_home='* hostapd: wlan?: STA * IEEE 802.11: authenticated*'
match_stillhome='* hostapd: wlan?: STA * WPA: group key handshake completed*'
match_away='* hostapd: wlan?: STA * IEEE 802.11: deauthenticated*'

sed_re_mac_only='s|.+[[:space:]]+STA[[:space:]]+||;s|[[:space:]]+.+||'


_syslog()
{
	logger -t wifi-tracker "$1"
}


_duration_human_readable()
{
	local seconds="$1"
	
	
	perl -MTime::Duration -wle \
	'print concise duration_exact shift' "$seconds" || echo "${seconds}s"
}


_status()
{
	local device="$1"
	local status="$2"
	local name="$device"
	
	
	local status_file="$device.status"
	local name_file="$device.name"
	local log_file="$device.log"
	local duration_file="$device.duration"
	
	local status_time=
	local status_duration=
	local status_duration_human_readable=
	
	local prev_status=
	local prev_status_time=
	local prev_status_duration=
	local prev_status_duration_human_readable=
	
	
	if [ -f "$status_file" ]
	then
		prev_status="`cat \"$status_file\"`"
	fi
	
	
	if [ -f "$name_file" ]
	then
		name="`cat \"$name_file\"`"
	fi
	
	
	if [ "$prev_status" -a "$prev_status" != "$status" ]
	then
		if [ -f "$log_file" ]
		then
			prev_status_time="`stat -f %m \"$log_file\"`"
			
			prev_status_duration="$((`date +%s` - $prev_status_time))"
			
			prev_status_duration_human_readable="`_duration_human_readable \"$prev_status_duration\"`"
			
			
			_syslog "$name $prev_status ($prev_status_duration_human_readable) -> $status"
		else
			_syslog "$name $prev_status -> $status"
		fi
		
		
		echo "`date +%s`|$status" >> "$log_file"
		
		
		if [ "$prev_status_duration" ]
		then
			echo "`date +%s`|$prev_status|$prev_status_duration" >> "$duration_file"
		fi
	else
		if [ -f "$log_file" ]
		then
			status_time="`stat -f %m \"$log_file\"`"
			
			status_duration="$((`date +%s` - $status_time))"
			
			
			if [ "$status_duration" -eq 0 ]
			then
				_syslog "$name is $status"
			else
				status_duration_human_readable="`_duration_human_readable \"$status_duration\"`"
				
				
				_syslog "$name is $status ($status_duration_human_readable)"
			fi
		else
			_syslog "$name is $status"
		fi
	fi
	
	
	echo "$status" > "$status_file"
}


while read line
do
	status=
	
	
	case "$line"
	in
		$match_home)      status=home ;;
		$match_stillhome) status=home ;;
		$match_away)      status=away ;;
	esac
	
	
	if [ "$status" ]
	then
		device="`echo \"$line\" | sed -E \"$sed_re_mac_only\" | tr -cd 0-9a-f:`"
		
		
		_status "$device" "$status"
	fi
done