#!/bin/sh

readonly SCRIPT_NAME="AutoBWPingModFQE"

#Settings
pingC=5						#Ping quantity
pingZ=120					#Optimal ping
pingIP=8.8.8.8				#Ping IP
WspolGora=133				#Ping factor upper limit in %
WspolDol=50					#Ping factor lower limit in %
download_lower_limit=4      #Download lower limit in Mbps
download_upper_limit=120    #Download upper limit in Mbps
transfactor=33				#Transmission speed in %

#Constants
pingS=0				#Starting value for average ping, currently not used
counter=0			#Counter

ping_based_speed() {

echo Ping IP: $pingIP
while [ "$counter" -lt $pingC ] ; do
	pingtest=$(ping -c 1 $pingIP | grep 'bytes from' | awk '{print $7}' | sed s/time=//)
	pingtest=${pingtest%.*}
	pingS=$((pingS+$pingtest))
	counter=$((counter+1))
	echo Ping:    $pingtest ms
	sleep 1
done

pingS=$((pingS / $pingC))
echo Average from $pingC pings $pingS ms

pingZ=$(echo " scale=2; $pingZ / $pingS * 100 " | bc -l)
pingZ=${pingZ%.*}

if [ $pingZ -lt $WspolDol ]; then
   	pingZ=$WspolDol
	echo Limiting ping factor to $(echo " scale=2; $WspolDol / 100 " | bc -l) "(lower limit)"
elif [ $pingZ -gt $WspolGora ]; then
	pingZ=$WspolGora
	echo Limiting ping factor to $(echo " scale=2; $WspolGora / 100 " | bc -l) "(upper limit)"
fi

pingZ=$(echo " scale=2; $pingZ / 100 " | bc -l)
echo Ping factor $pingZ

old_Kbps_down=$(nvram get qos_ibw)
echo QOS Download old $old_Kbps_down Kbps
Kbps_down=$(echo " $old_Kbps_down * $pingZ " | bc -l)
Kbps_down=${Kbps_down%.*}
echo QOS Download new $Kbps_down Kbps
}

update_via_TC_down() {
	#read parameters for tc
	PARMS=""
	OVERHEAD=$(nvram get qos_overhead)
	if [ ! -z "$OVERHEAD" ] && [ "$OVERHEAD" -gt "0" ] ; then
			ATM=$(nvram get qos_atm)
			if [ "$ATM" == "1" ] ; then
					PARMS="overhead $OVERHEAD linklayer atm "
			else
					PARMS="overhead $OVERHEAD linklayer ethernet "
			fi
	fi

	#Calculate scale factor based on new/old speeds. This factor will be used to scale class rates & ceils
	#If old speeds are 0, just set the scale factor to 1 (cannot divide by 0)
#	if [ "$old_Kbps_up" -eq "0" ]; then
#		uscale_factor=1.0
#	else
#		uscale_factor=$( echo "$Kbps_up/$old_Kbps_up" | bc -l )
#	fi
	if [ "$old_Kbps_down" -eq "0" ]; then
		dscale_factor=1.0
	else
		dscale_factor=$( echo "$Kbps_down/$old_Kbps_down" | bc -l )
	fi

	printf "%s           %8.3f            %8.3f\n" "Scaling by" $dscale_factor

	echo
	echo "              ====================================== DOWNLOAD ======================================"
	echo "               ----------------- RATE -----------------    ----------------- CEIL -----------------"
	echo "Class            Previous (Kbps)        New (Kbps)           Previous (Kbps)         New (Kbps) "
	echo "-----          -------------------  -------------------    -------------------  -------------------"
	while read -r line;
	do
		class=$( echo ${line} | sed -n -e 's/.*class htb 1://p' | cut -d' ' -f1 )
		prio=$( echo ${class} | cut -c 2 )

		prevRate=$( echo ${line} | awk -F"rate |K?M?G?bit" '{print $2}' )
		prevCeil=$( echo ${line} | awk -F"ceil |K?M?G?bit" '{print $3}' )
		rateUnit=$( echo ${line} | cut -d' ' -f11)
		rateUnit=${rateUnit//[0-9]/}
		ceilUnit=$( echo ${line} | cut -d' ' -f15)
		ceilUnit=${ceilUnit//[0-9]/}
		if [ "$rateUnit" = "bit" ]; then
			prevRate=$( echo "$prevRate*0.001" | bc -l)
		fi
		if [ "$rateUnit" = "Mbit" ]; then
			prevRate=$( echo "$prevRate*1000" | bc -l)
		fi
		if [ "$rateUnit" = "Gbit" ]; then
			prevRate=$( echo "$prevRate*1000000" | bc -l)
		fi

		if [ "$ceilUnit" = "bit" ]; then
			prevCeil=$( echo "$prevCeil*0.001" | bc -l)
		fi
		if [ "$ceilUnit" = "Mbit" ]; then
			prevCeil=$( echo "$prevCeil*1000" | bc -l)
		fi
		if [ "$ceilUnit" = "Gbit" ]; then
			prevCeil=$( echo "$prevCeil*1000000" | bc -l)
		fi

		Burst=$( echo ${line} | sed -n -e 's/.* burst \([a-zA-Z0-9]*\).*/\1/p' )
		Cburst=$( echo ${line} | sed -n -e 's/.*cburst \([a-zA-Z0-9]*\).*/\1/p' )

		Rate=$(echo "$prevRate*$dscale_factor" | bc -l)
		Ceil=$(echo "$prevCeil*$dscale_factor" | bc -l)

		printf "%2.0f                 %10.1f         %10.1f                %10.1f         %10.1f\n" $class $prevRate $Rate $prevCeil $Ceil

		#Debug
		#echo -e "$line\n class=$class\n prio=$prio\n Rate=$Rate\n Ceil=$Ceil\n Burst=$Burst\n Cburst=$Cburst\n"

		#echo -e "tc class change dev br0 parent 1:1 classid 1:${class} htb ${PARMS}prio ${prio} rate ${Rate}Kbit ceil ${Ceil}Kbit burst ${Burst} cburst ${Cburst}"
		Rate=$(echo $Rate | cut -d. -f1)
		Ceil=$(echo $Ceil | cut -d. -f1)

		tc class change dev br0 parent 1:1 classid 1:${class} htb ${PARMS}prio ${prio} rate ${Rate}Kbit ceil ${Ceil}Kbit burst ${Burst} cburst ${Cburst}

	done <<EOF
                $( tc class show dev br0 | grep "parent 1:1 " )
EOF
}

update_via_restart_qos_flexqos_check(){
		service restart_qos >/dev/null 2>&1
		/jffs/addons/flexqos/flexqos.sh -check &
}

checking_and_applying_limits() {

download_lower_limit=$(echo "$download_lower_limit*1024" | bc -l)
download_upper_limit=$(echo "$download_upper_limit*1024" | bc -l)

if [ $Kbps_down -lt $download_upper_limit ]; then
	if [ $Kbps_down -lt $download_lower_limit ]; then
		nvram set qos_ibw=$download_lower_limit
		nvram commit
		update_via_TC_down # for testing change to update_via_restart_qos_flexqos_check
		logger -t $SCRIPT_NAME QOS Download set to $download_lower_limit Kbps "(LOW LIMIT)", average from $pingC pings $pingS ms
		echo $SCRIPT_NAME 1 QOS Download set to $download_lower_limit Kbps "(LOW LIMIT!!!)", average from $pingC pings $pingS ms
	else
		nvram set qos_ibw=$Kbps_down
		nvram commit
		update_via_TC_down # for testing change to update_via_restart_qos_flexqos_check
		logger -t $SCRIPT_NAME QOS Download set to $Kbps_down Kbps, average from $pingC pings $pingS ms
		echo $SCRIPT_NAME 2 QOS Download set to $Kbps_down Kbps, average from $pingC pings $pingS ms
	fi
else
		logger -t $SCRIPT_NAME "QOS Download doesn't change, average from" $pingC pings $pingS ms
		echo $SCRIPT_NAME 3 "QOS Download doesn't change, average from" $pingC pings $pingS ms
fi
}

#Limiting Transmission Download
translimit() {
	transfactor=$(echo " 100 / $transfactor " | bc -l)
	transfactor=${transfactor%.*}
	Kbps_downtrans=$(echo " $Kbps_down / $transfactor / 8 " | bc -l)
	Kbps_downtrans=${Kbps_downtrans%.*}
	echo Limit transmission: $Kbps_downtrans
	transmission-remote -d $Kbps_downtrans > /dev/null 2>&1
}

#Saving recent download limit to file
saving_to_file() {
	QOSD=$(nvram get qos_ibw)
	QOSD=$(echo "scale=0; $QOSD / 1024;" | bc -l)
	echo QOSD: "$QOSD" Mbps > /mnt/Trans/Finished/qos.txt
}

########### START HERE ###########

ping_based_speed
checking_and_applying_limits
translimit