#!/bin/sh
#
# Automatically try to connect an FreeBSD Client  to Wireless Leiden Network
# and or maintain connection status.
#
# Tip: Place it in crontab like this:
#   */5	* * * *	root /usr/local/sbin/wl-auto-connect --auto 2>&1 | /usr/bin/logger -t wl-auto-connect
#
# Rick van der Zwet <info@rickvanderzwet.nl>
#
WIRELESS_IF=wlan0
WIRED_IF=`ifconfig -l | tr ' ' '\n' | grep -v -e lo0 -e bridge0 -e ath0 -e wlan0 | head -1`
SSID_FILTER='-e ^ap-WirelessLeiden'
WAIT_DELAY=10

# This function is special to WirelessLeiden Announcement, try to find your own
# announcement method for any other use
announce_client() {
  echo "# INFO: Announcing Client available"
  if ! `fetch -q http://dyndns.wleiden.net/dyndns/update/$(hostname -s)/`; then
    echo "# WARN: Hostname announcement failed!"	
    exit 2
  fi
}

connect_client() {
  # Do we need to connect to the Wired Interface
  if `ifconfig $WIRED_IF | grep -q 'status: active'`; then
    if `dhclient $WIRED_IF`; then
      announce_client
      exit 0
    else
      echo "# ERROR: $WIRED_IF has ethernet connection but DHCP not working"
    fi
  fi
  
  # Find out the SSIDs to connect to
  AVAILABLE_SSIDS=`ifconfig -v $WIRELESS_IF list scan | grep $SSID_FILTER |  awk '{print $5 " " $1}' | sort -t: -k1 -nr | awk '{print $2}'`
  if [ -z "$AVAILABLE_SSIDS" ]; then
    echo "# ERROR: Cannot find an (Wireless Leiden) AccessPoints"
    exit 1
  fi
  
  # Attempt to make an connection to one of the available SSIDs
  for AVAILABLE_SSID in $AVAILABLE_SSIDS; do
    echo "# INFO: Trying to connect with $WIRELESS_IF to $AVAILABLE_SSID"
    ifconfig $WIRELESS_IF ssid $AVAILABLE_SSID up
    echo "# INFO: Sleeping $WAIT_DELAY for interface $WIRELESS_IF to settle"
    sleep $WAIT_DELAY
    
    if `ifconfig $WIRELESS_IF | grep -q 'status: associated'`; then
      echo "# INFO: Connection established of $WIRELESS_IF to $AVAILABLE_SSID"
      if `dhclient $WIRELESS_IF`; then
        announce_client
        exit 0
      fi
    else
      echo "# WARN: Connection of $WIRELESS_IF to $AVAILABLE_SSID failed!"
    fi
  done
  
  echo "# ERROR: Unable to connect to the network"
  exit 1
}


if [ -z "$1" -o "$1" == "--help" ]; then
  echo "Usage: $0 [--help|--auto|--force]" 1>&2
  echo  "  --help    :    Reading right now" 1>&2
  echo  "  --auto    :    Attempt auto-configuration" 1>&2
  echo  "  --force   :    Force configured setup to re-connect" 1>&2
  exit 128
elif [ "$1" == "--force" ]; then
  connect_client
elif [ "$1" == "--auto" ]; then
  # If we cannot ICMP ping the gateway we have to reconnect
  DEFAULTROUTE=`route get default | awk '/gateway:/ {print $2}'`
  if [ -n "$FORCE_UPDATE" ]; then
    connect_client
  elif [ -z "$DEFAULTROUTE" ]; then
    connect_client
  elif ! `ping -c 3 -t 1 $DEFAULTROUTE > /dev/null`; then
    connect_client
  else
    # Phone Home
    announce_client
  fi
fi