#!/bin/bash
# -*- sh -*-
set -o pipefail

: << =cut

=head1 NAME

dd-wrt-wifi-devices_ - How many Wifi devices are connected to a DD-WRT router?

Tested with DD-WRT v3.0-r44715

=head1 CONFIGURATION

Configure the hostname by adding the IP address to the symlink name:
Symlink "dd-wrt-wifi-devices_" to "dd-wrt-wifi-devices_192.168.1.1"

=head2 ENVIRONMENT VARIABLES

 host      - Hostname of router
 user      - Web interface username
 password  - Web interface password
 host_name - To put the graph onto a different host

=head2 CONFIGURATION EXAMPLE

  [dd-wrt-*]
  env.user tpli
  env.password thisismypassword

=head2 HOST MANAGEMENT

You can display the graph on another host (e.g., the actual router) than the
one running dd-wrt-wifi-devices.
To do so, first configure the plugin to use a different hostname.

  env.host_name router

Then configure munin (in /etc/munin/munin-conf or /etc/munin/munin-conf.d)
to support a new host.

  [example.net;router]
    address 127.0.0.1
    use_node_name no


=head1 REQUIREMENTS

"bash" and "curl" are required.

=head1 SEE ALSO

https://github.com/Tafkas/fritzbox-munin

=head1 AUTHOR
Christian Weiske <cweiske@cweiske.de>

=head1 LICENSE

AGPL-3.0-only https://spdx.org/licenses/AGPL-3.0-only.html

=head1 MAGIC MARKERS

#%# family=manual

=cut

if [ -z "$host" ]; then
    host=$(basename "$0" | sed 's/dd-wrt-wifi-devices_//g')
fi
user=${user:-root}
pass=${password:-admin}

case $1 in
   config)
       echo "graph_title DD-WRT $host connected Wifi devices"
       echo "graph_vlabel Number of devices"
       echo "graph_args --base 1000"
       echo "graph_category network"
       echo "graph_order wifi"
       echo "wifi.label Wifi Connections"
       echo "wifi.type GAUGE"
       echo "wifi.graph LINE1"
       if [ -n "$host_name" ]; then
           echo "host_name $host_name"
       fi
       exit 0;;
esac

url="http://$host/Status_Wireless.live.asp"

count=$(
    curl --silent --show-error --fail --user "$user:$pass" --max-time 3 "$url"\
        | grep -o 'assoc_count::[0-9]*'\
        | cut -d':' -f 3
)
#without "-o pipefail" we would not get curl's exit code here
exitcode=$?
if [ "$exitcode" -gt 0 ]; then
    count="U"
fi

echo "wifi.value $count"