#!/bin/bash
# set -xv
# General part ------------------------------------------
source /opt/scripts/mesh/freq.sh # get center frequency of channel like this: ${chan2g["1"]} 'OR' ${chan5g["149"]}
PHYNAME=$1
DEVNAME=$2
CHANNEL=${chan[$3]}
POWER=$4
NOISEFLOOR=$5
phy_number="${1//[!0-9]/}"
dev_number="${2//[!0-9]/}"
devPath="/sys/class/net/"
phyPath="/sys/kernel/debug/ieee80211/"

Monitoring=0
MonNode="apu01"

# get the hostname
host_valid=0
nodename="$(uname -n)"
echo "Hostname: $nodename"
source /opt/scripts/mesh/node_addresses.sh
ALLNODES=${neighbors["all"]}

# apply TCP/UDP send/receive socket buffer (rmem/wmem) optimizations
sysctl -w net.core.rmem_max=8388608						#->   8MB
sysctl -w net.core.wmem_max=8388608						#->   8MB
sysctl -w net.core.rmem_default=8388608					#->   8MB
sysctl -w net.core.wmem_default=8388608					#->   8MB
sysctl -w net.core.optmem_max=8388608					#->   8MB
sysctl -w net.ipv4.tcp_mem='8388608 8388608 8388608'	#->   8MB   8MB   8MB
sysctl -w net.ipv4.tcp_rmem='4096 87380 8388608'		#->   4kB  85kB	  8MB
sysctl -w net.ipv4.tcp_wmem='4096 65536 8388608'		#->   4kB  64kB	  8MB
sysctl -w net.ipv4.udp_mem='8388608 8388608 8388608'	#->   8MB   8MB   8MB
sysctl -w net.ipv4.udp_rmem_min=4096					#->   4kB
sysctl -w net.ipv4.udp_wmem_min=4096					#->   4kB
sysctl -w net.core.netdev_max_backlog=5000
sysctl -w net.ipv4.tcp_max_syn_backlog=5000

# TCP SYN/SYN-ACK timeout optimizations
sysctl -w net.ipv4.tcp_syn_retries=9		# 9 instead of 6 ((0s) 3s 6s 12s 24s 48s 96s 192s 384s 768s -> total 1533s)
sysctl -w net.ipv4.tcp_synack_retries=9		# 9 instead of 5 ((0s) 3s 6s 12s 24s 48s 96s 192s 384s 768s -> total 1533s)

# deactivate TCP metrics history
sysctl -w net.ipv4.tcp_no_metrics_save=1

# clear routing table cache
sysctl -w net.ipv4.route.flush=1

# deactivate TCP CUBIC Hystart mechanism
echo 0 > /sys/module/tcp_cubic/parameters/hystart
echo 0 > /sys/module/tcp_cubic/parameters/hystart_detect

# apply ARP cache optimizations
sysctl -w net.ipv4.neigh.default.base_reachable_time_ms=1200000		#-> 30 min instead of 30 sec
sysctl -w net.ipv4.neigh.default.mcast_solicit=25					#-> 25 instead of 3 multicast attempts
sysctl -w net.ipv4.neigh.default.ucast_solicit=25					#-> 25 instead of 3 unicast attempts

# check whether the phy exists
if [ -e "$phyPath$PHYNAME" ]; then
	echo "$PHYNAME exists in $phyPath, going on ..."
else
	echo "$PHYNAME do not exist in $phyPath, exit script ..."
	exit
fi

systemctl stop systemd-timesyncd.service

# check whether the wanted DEVNAME already exists and remove it
if [ -e "$devPath$DEVNAME" ]; then # if dev already exists
	number=$(iw dev "$DEVNAME" info | awk '$1 == "wiphy" {print $2}')
	echo "Removing existing device $DEVNAME from phy$number"
	ifconfig $DEVNAME down
	iw dev $DEVNAME del
fi

# get current dev on the specified phy
# delete any dev on specified phy
current_dev_on_phy=$(iw dev | awk -v phy="$phy_number" '$0 ~ "phy#"phy {getline; while ($1 ~ /^Interface/) {print $2; getline}}')
if [ ! -z "$current_dev_on_phy" ]; then
	echo "Removing existing device $current_dev_on_phy from phy$phy_number"
	ifconfig $current_dev_on_phy down
	iw dev $current_dev_on_phy del
fi

# monitor node
if [[ "$nodename" == "$MonNode" ]] && [[ $Monitoring -eq 1 ]]; then
	iw phy0 interface add mon0 type monitor
	ifconfig mon0 up
fi

# creating the new dev
# mesh_id is set to DEVNAME so that in case of init both phys they are in different mesh`s
echo "Creating new mesh device ${DEVNAME} on ${PHYNAME}"
iw phy ${PHYNAME} interface add ${DEVNAME} type mp mesh_id ${DEVNAME}

ifconfig ${DEVNAME} down 					# if interface was up

iw dev ${DEVNAME} set type mp				# set type mesh point
iw phy ${PHYNAME} set antenna 3 3			# ath9k/AR9280: OK (TX=3 RX=3)
iw phy ${PHYNAME} set retry short 7 long 4	# initialize adapter with default (re-)try limits
iw phy ${PHYNAME} set rts off				# deactivate RTS/CTS (default)
# iw phy ${PHYNAME} set rts 500				# request to send (packet size threshold 500 octets/byte)
# iw phy ${PHYNAME} set rts 9999999999		# request to send (packet size threshold 500 octets/byte)
# iw phy ${PHYNAME} set retry short 7 long 4	# initialize adapter with default (re-)try limits
iw dev ${DEVNAME} set mesh_param mesh_max_peer_links=50

iw dev ${DEVNAME} set power_save off		# deactivate power saving mechanism
ifconfig ${DEVNAME} up						# set interface up

iw dev ${DEVNAME} mesh leave
iw dev ${DEVNAME} mesh join mesh freq ${CHANNEL} HT40+ basic-rates 54 mcast-rate 54
# iw dev mesh0 mesh join mesh freq 5745 HT40+ basic-rates 54 mcast-rate 54
iw dev ${DEVNAME} set txpower fixed $POWER 								# set tx power (300 eq 3dBm)
# iw dev ${DEVNAME} set rtcts off

if [[ $3 -lt 15 ]]; then # set coding scheme and guard interval (set short for 400ns)
	iw dev ${DEVNAME} set bitrates ht-mcs-2.4 6 sgi-2.4
else
	iw dev ${DEVNAME} set bitrates ht-mcs-5 6 sgi-5
fi

echo 0 > /sys/kernel/debug/ieee80211/${PHYNAME}/ath9k/ani 				# set fixed noise floor in dBm
echo ${NOISEFLOOR} > /sys/kernel/debug/ieee80211/${PHYNAME}/ath9k/nf_override	#TODO: overwritten individually below

# set mintsrel_ht to fixed rate
#															 -    station    -
# cat /sys/kernel/debug/ieee80211/phy0/netdev:mesh0/stations/04:f0:21:ac:31:bd/rc_stats 
echo 198 > /sys/kernel/debug/ieee80211/${PHYNAME}/rc/fixed_rate_idx


# automatically remove inactive links from station list
#iw dev ${DEVNAME} set mesh_param mesh_plink_timeout=20			# timeout in seconds

# Node specific part ------------------------------------------
# # get the hostname
# host_valid=0
# nodename="$(uname -n)"
# echo "Hostname: $nodename"
# source /opt/scripts/mesh/node_addresses.sh
# ALLNODES=${neighbors["all"]}

# check wheather hostname is valid
while [[ host_valid -eq 0 ]]; do
	for i in $ALLNODES; do
		if [[ $nodename == $i ]]; then
			host_valid=1
			echo "Hostname $nodename is valid"
			break
		fi
	done
	if [[ host_valid -eq 0 ]]; then
		sleep 1
		nodename="$(uname -n)"
	fi
done

# removing all IPs from dev
ip addr flush dev ${DEVNAME}

# get the dev corresponding IP
if [[ "$dev_number" -eq 0 ]]; then
	NODE_MESH_IP=${phy0IP["$nodename"]}
	BROADCAST_IP=${phy0IP["broadcast"]}
fi
if [[ "$dev_number" -eq 1 ]]; then
	NODE_MESH_IP=${phy1IP["$nodename"]}
	BROADCAST_IP=${phy1IP["broadcast"]}
fi
echo "The node mesh ip is: $NODE_MESH_IP"
ip -4 addr add ${NODE_MESH_IP}/24 broadcast $BROADCAST_IP dev ${DEVNAME}

source /opt/scripts/mesh/block_peer_links.sh

set +x