#!/bin/bash
#
# elrandom v4.2, last updated 11/26/2019
# 
# Script to connect to a random Echolink node, by K0KN 2/2011
#
# Usage = elrandom [your node#] [2] [3]         ; 2=monitor only   3=transceive
#
# Note: W3m is required to create node list. Install w3m with apt-get or yum if necessary 
#
# The "echolinkrandom" and other custom audio files are available via WGET:
# wget www.qsl.net/k0kn/k0kn_extra_sounds.tgz
# 
# You can place any node numbers that you do not wish to dial in the DENYLIST file specified below, one per line. Do not
# leave any blank lines in this file. For example: (do not include the # of course)
#
# 327890
# 009999

selectattempt=3
# Set this number to the maximum number of attempts you would like this script to make
CUSTOM=/dev/shm
LISTURL="http://www.echolink.org/logins.jsp"
LOGFILE="/var/log/asterisk/connectlog"
NODELIST="/dev/shm/echolink_nodelist"
DENYLIST="/home/kyle/elrandom_deny"
RANDOMSOUND="/etc/asterisk/sounds/echolinkrandom"
ERRORSOUND="/var/lib/asterisk/sounds/an-error-has-occurred"
retrycount=0
selectcount=0
denynode=""
LOCALNODE=$1

if [ "$1" == "" -o "$2" == "" ] ; then
echo "Usage = elrandom [your node#] [2] [3]"; exit
fi

if ! [ -f $DENYLIST ] ; then
touch $DENYLIST
fi

#############################################

downloadnodelist ()
{
# Create / update local nodelist
retrycount=$((retrycount + 1))
if [ $retrycount == 10 ] ; then
echo $(date) "Error downloading Echolink nodelist" >> $LOGFILE ; echo "Error downloading nodelist -- exiting" ; exit ; fi
if ! [ -f $NODELIST ] ; then echo "No nodelist found - downloading" ; w3m -dump -cols 120 $LISTURL > "$NODELIST"2 ; checknodelist
cp "$NODELIST"2 $NODELIST
fi

if [ "$(( $(date +"%s") - $(stat -c "%Y" $NODELIST) ))" -gt "1800" ]
then
echo "Nodelist over 30 minutes old - downloading new"
w3m -dump -cols 120 $LISTURL > "$NODELIST"2 ; checknodelist
fi
}

checknodelist ()
{

# Check nodelist for proper header
HEADER=$(grep 'Current Logins' "$NODELIST"2)
if [ "$HEADER" != "" ] ; then
echo "Header check complete"
else
echo "Header does not match" ; downloadnodelist
fi

# Check nodelist for proper footer
FOOTER=$(grep '[Conferences]' "$NODELIST"2)
if [ "$FOOTER" != "" ] ; then
echo "Footer check complete"
else
echo "Footer does not match" ; downloadnodelist
fi

# Remove header
if [ -f "$NODELIST"2 ]
then
awk 'FNR>13{print}' "$NODELIST"2 > $NODELIST
fi

# Remove footer
if [ -f "$NODELIST"2 ]
then
sed '/^$/d' $NODELIST > "$NODELIST"2
sed '$d' < "$NODELIST"2 > $NODELIST
cut -c30-88 $NODELIST > "$NODELIST"2
cp "$NODELIST"2 $NODELIST
rm -f "$NODELIST"2
fi
}

selectrandom ()
{
selectcount=$((selectcount + 1))
denynode=""
echo "selectcount: $selectcount"
if [ $selectcount -gt $selectattempt ] ; then
echo $(date) "Random Echolink script - attempt $selectcount. Maximum $selectattempt. Giving up" >> $LOGFILE
asterisk -rx "rpt localplay $LOCALNODE $ERRORSOUND"
echo "Attempt $selectcount. Maximum $selectattempt. Giving up" ; exit
fi

# Count number of stations listed
wc -l "$NODELIST" > "$CUSTOM"/el_random_count
LINES=$(cut -d " " -f1 "$CUSTOM"/el_random_count)
LINES=$(( $LINES - 2 ))
echo ""
echo "Number of logged in nodes: $LINES"

# Generate Random Line # between 1 and number of lines in file
RAN_NODE=$[ ( $RANDOM % $LINES )  + 1 ]
echo "random number =" $RAN_NODE

# Copy Random line to temp file
sed -n ""$RAN_NODE"p" "$NODELIST"  > "$CUSTOM"/el_random_node

# Parse temp file
CALLSIGN=$(cut -c 1-10 "$CUSTOM"/el_random_node)
node_num=$(cut -c 54-59 "$CUSTOM"/el_random_node)
NODENAME=$(cat "$CUSTOM"/el_random_node)
echo $node_num > "$CUSTOM"/random_enode_dialed

# Remove whitespaces
node_num=$(echo $node_num | tr -d ' ')
callsign=$(echo $callsign | tr -d ' ')

# Expand node number to 6 digits
node_num=$(printf "%06d\n" $node_num)
# node_num=$(awk '{printf "%006s\n", $0}' "$CUSTOM"/random_enode_dialed)
echo $node_num > "$CUSTOM"/random_enode_dialed

# Display to console
echo "callsign =" $CALLSIGN
echo "node_num =" $node_num
echo ""
#
checkdeny
}

checkdeny ()
{
# Check to see if random node is in deny list
while IFS= read -r line
do
echo "Deny node: $line"
if [ "$line" = "$node_num" ] ; then
 echo "Random node in deny list! Denied node - $node_num $CALLSIGN"
echo $(date) "Random Echolink script - denied node $node_num ($CALLSIGN) $NODENAME" >> $LOGFILE
denynode="deny"
fi
done < $DENYLIST
#
if [ "$denynode" = "deny" ] ; then
selectrandom
fi
}

###########################################

asterisk -rx "rpt localplay $LOCALNODE $RANDOMSOUND"

# Delete nodelist if zero bytes
if ! [ -s $NODELIST ] ; then rm -f $NODELIST ; fi

# Run Check/download nodelist routine
downloadnodelist

# Select random station
selectrandom

###############################

# Node logging
echo $(date) "Random Echolink script - $1 called $ECHOINFO $NODENAME" >> $LOGFILE

# Make Call
echo "Sending command: rpt fun $1 *$23$node_num"
asterisk -rx "rpt fun $1 *$23$node_num"

sleep 2

exit 0