ProximityDetector

#!/bin/sh

DEVICE="xx:xx:xx:xx"
CHECK_INTERVAL=5
HCITOOL="/usr/bin/hcitool"
DEBUG="/home/raspberry/.log/btproximity.log"


function msg {
    echo "$1" >> $DEBUG
}

function msgn {
    echo -n "$1" >> $DEBUG
}

function check_connection {
    connected=0;
    found=0
    for s in `$HCITOOL con`; do
        if [[ "$s" == "$DEVICE" ]]; then
            found=1;
        fi
    done
    if [[ $found == 1 ]]; then
        connected=1;
    else
       msgn 'Attempting connection...'
        if [ -z "`sudo $HCITOOL cc $DEVICE 2>&1`" ]; then
            msg 'Connected.'
            connected=1;
        else
            msg "ERROR: Could not connect to device $DEVICE."
        fi
    fi
}

function start_mocp {
    if ! ps aux | grep -w "mocp" | grep -v grep > /dev/null ; then
	mocp -S
	mocp -o shuffle
	mocp -p
    else
	mocp -G
    fi
}

check_connection

while [[ $connected -eq 0 ]]; do
    check_connection
    sleep 1
done

name=`$HCITOOL name $DEVICE`
msg "Monitoring proximity of \"$name\" [$DEVICE]";

state="NotDetectable"
while /bin/true; do
    check_connection

    if [[ $connected -eq 1 ]]; then
	if [[ "$state" == "NotDetectable" ]]; then
                rssi=`$HCITOOL rssi $DEVICE | sed -e 's/RSSI return value: //g'`
        	msg "*** Device \"$name\" [$DEVICE] is now detectable (signal: $rssi)"
	        state="Detectable"
        	start_mocp > /dev/null 2>&1
        	CHECK_INTERVAL=5
        fi
        

    elif [[ "$state" == "Detectable" ]]; then
            msg "*** Device \"$name\" [$DEVICE] is no longer detectable"
            state="NotDetectable"
            start_mocp > /dev/null 2>&1
            CHECK_INTERVAL=2
    fi

    msg "state = $state, PID = $PID, sleep = $CHECK_INTERVAL"

    sleep $CHECK_INTERVAL
done