#!/bin/bash

# Find the available wireless interface:
# FIXME this doesn't currently cope with more than one interface.
IF=`cat /proc/net/wireless | awk 'NR>2 {print $1}' | tr -d ':'`
if [ -z "${IF}" ]
then
  echo "No wireless interfaces found"
  exit 1
fi

tmpfile=`mktemp`
trap "rm ${tmpfile}" 0

# Find the networks accessible via that interface.
iwlist ${IF} scanning | awk '
BEGIN             { essid=""; }
                  { val=substr($0,index($0,":")+1); }
/ESSID:/          { essid=substr(val,2,length(val)-2); }
/Mode:/           { mode=val; }
/Channel:/        { channel=val; }
/Quality:/        { quality=substr(val,0,index(val,"/")); }
/Encryption key:/ { enc=val; }
/Cell /           { if (essid!="") print quality,channel,enc,mode,essid; }
END               { if (essid!="") print quality,channel,enc,mode,essid; }
' |

# Sort by quality
sort -rn |

# Format for dialog
awk '{ quality=$1; channel=$2; enc=$3; mode=$4; essid=$5;
       printf("\"%s %s %s\" \"%s %s\" ",essid,channel,enc,mode,quality); }' > ${tmpfile}

# Give up if no networks found.
if [ ! -s ${tmpfile} ]
then
  echo "No networks found"
  exit 1
fi

trap "rm ${tmpfile}; clear" 0

# Present a menu of available networks.
# (It would not be a bad idea to provide some way to enter details of networks that are
# not broadcasting their ESSIDs.)
eval dialog --menu \"Wireless Networks\" 15 50 15 `cat ${tmpfile}` 2>${tmpfile}
case $? in
1) exit 0 ;;
esac
read essid channel enc < ${tmpfile}

# Set up the interface according to the selection.
iwconfig ${IF} essid ${essid}
iwconfig ${IF} channel ${channel}

# Is there encryption?
case ${enc} in
off) iwconfig ${IF} key off
     exit 0 ;;
esac

# This seems to be necessary for the RT2860STA driver:
iwpriv ra0 set EncrypType=WEP

# Ask for a password:
dialog --insecure --passwordbox "Password for ${essid}" 15 50 2>${tmpfile}
case $? in
1) exit 0 ;;
esac

# Tell the interface about the password.
iwconfig ${IF} key "`cat ${tmpfile}`"