# Uses wireless_tools, to check for association to a network.
# wep_check interface [timeout]
wep_check()
{
    local INTERFACE=$1 TIMEOUT=${2:-15} timeout=0 bssid

    while [[ $timeout -ne $TIMEOUT ]]; do
        bssid=`iwgetid $INTERFACE -ra`
        [[ -n "$bssid" && "$bssid" != "00:00:00:00:00:00" ]] && return 0
        sleep 1
        let timeout++
    done
    return 1
}

# Check if a particular network is within range
# find_essid interface essid connection (we treat ESSID as regexp when CONNECTION=wireless-dbus)
find_essid() {
    local INTERFACE="$1" ESSID="$2" CONNECTION="$3" RETRIES=20 try=0 res scanned
    while [[ "$try" -lt "$RETRIES" ]]; do
        sleep 0.5
        let try++
        if [[ "$CONNECTION" == wireless-dbus ]]; then
            # JP: ESSID is a regexp
            found=$(
                    res=$(iwlist "$INTERFACE" scan 2>/dev/null)
                    [[ -z "$res" ]] && exit 1
                    # if results were non-null, process them and exit 0
                    echo "$res" | sed -nr 's/^\s+ESSID:"([^"]*)"$/\1/p' | egrep -xm1 "$ESSID"
                   )
        else
            found=$(
                    res=$(iwlist "$INTERFACE" scan 2>/dev/null)
                    [[ -z "$res" ]] && exit 1
                    # if results were non-null, process them and exit 0
                    echo "$res" | sed -nr 's/^\s+ESSID:"([^"]*)"$/\1/p' | fgrep -xm1 "$ESSID"
                   )
        fi && { 
                scanned=1
                report_debug find_essid "\"$found\""
                # we only bother with at most 5 successful scans
                if (( try < RETRIES-4 )); then try=$((RETRIES-4)); fi
              }
        if [[ -n "$found" ]]; then
            echo "$found"       # JP: echo literal ESSID
            return 0 # network found
        fi
    done
    if [[ "$scanned" -ne 1 ]]; then
        report_debug find_essid "unable to scan"
    fi
    return 1
}

# Check if a particular network is within range
# find_ap interface ap
find_ap() {
    local INTERFACE="$1" ap=$(echo "$2" | tr 'abcdef' 'ABCDEF') RETRIES=20 try=0 res scanned
    while [[ "$try" -lt "$RETRIES" ]]; do
        sleep 0.5
        let try++
        found=$(
            res=$(iwlist "$INTERFACE" scan 2> /dev/null)
            [[ -z "$res" ]] && exit 1
            # if results were non-null, process them and exit 0
            echo "$res" | sed -nr '/^\s+Cell .. - Address: ([[:xdigit:]:]+)$/ { s//\1/; N; s/(.*)\n\s+ESSID:"([^"]*)"$/\1\t\2/p }' \
            | egrep -m1 "^$ap\t"
            ) && {
                    scanned=1
                    report_debug find_ap "\"$found\""
                    # we only bother with at most 5 successful scans
                    if (( try < RETRIES-4 )); then try=$((RETRIES-4)); fi
                 }
        if [[ -n "$found" ]]; then
            echo "$found" | cut -f2     # JP: echo literal ESSID
            return 0
        fi
    done
    if [[ "$scanned" -ne 1 ]]; then
        report_debug find_ap "unable to scan"
    fi
    return 1
}

# Return a filename containing a list of network APs and ESSIDs found (sorted by decreasing signal strength)
# list_networks interface
list_networks()
{
    local INTERFACE="$1" essids try=0 RETRIES=20 res scanned
    # temp file used, as keeping ESSID's with spaces in their name in arrays 
    # is hard, obscure and kinda nasty. This is simpler and clearer.
 
    [[ -z "$INTERFACE" ]] && return 1
    essids=$(mktemp /tmp/essid.XXXXXXXX)

#     # James suggested using this, but it requires wpa_supplicant to be running
#     wpa_cli -i "$INTERFACE" scan 2>/dev/null || { rm $essids; return 1; }
#     sleep 0.5
#     wpa_cli -i "$INTERFACE" scan_results > $essids 2>/dev/null || { rm $essids; return 1; }

    {
    while [[ "$try" -lt "$RETRIES" ]]; do        
            sleep 0.5
            let try++
          # iwlist "$INTERFACE" scan 2> /dev/null | fgrep "ESSID" | sed 's/.*ESSID:"\([^"]\+\)".*/\1/' > $essids
            res=$(iwlist "$INTERFACE" scan 2> /dev/null)
            [[ -z "$res" ]] && continue 
            scanned=1
            # we only bother with at most 5 successful scans
            if (( try < RETRIES-4 )); then try=$((RETRIES-4)); fi
            echo "$res" | sed -r '1d; $ { H; ba }; 2 { h; d }; /^\s+Cell /! { H; d }; :a; x; s/\n/ /g'
    done
    } \
        | sed -rne 's/.*Address: ([[:xdigit:]:]+).*ESSID:"([^"]*)".*Quality=([0-9]+).*/\1\t\3\t\1\t\2/p' \
            -e 's/.*Address: ([[:xdigit:]:]+).*Quality=([0-9]+).*ESSID:"([^"]*)".*/\1\t\2\t\1\t\3/p' \
        | sort -k1 -k2nr | uniq -w17 \
        | sort -k2nr \
        | cut -f3- > "$essids"
    # 1. make tab-separated fields: ap, signal-strength, ap, essid (easiest way to use uniq and cut here requires ap twice)
    # 2. eliminate duplicate aps (keeping strongest signal)
    # 3. sort entire list by decreasing signal
    # 4. then return tab-separated fields: ap, essid (ap needs to come first so that read can assume format is <word> <rest of line>)
  
    # File of 0 length, ie. no ssid's.
    if [[ ! -s $essids ]]; then
        rm -f $essids 
        return 1
    fi

    echo $essids
    return 0
}
# vim: set ts=4 et sw=4 ft=sh: