# Monitors for *remote* door lock/unlock commands from the fob and uses those to disable/enable the Raspberry Pi's WiFi transmitter.
#
# Locked = WiFi Off (secure)
# Unlocked = WiFi On (less secure)

# Tunable variables:

# Name for the CAN-IHS interface (can0, can1, vcan0, etc)
CANIHS=can0
WIFIDEV=wlan0
DEBUG=true   # Values: true,false,raw

LASTREMOTE="1C0#FFFFFFFFFFFF"
sleep 5

candump -L $CANIHS,01C0:0FFFF | while read time bus REMOTE
do

[ $DEBUG == "raw" ] && echo CAN-IHS data: $REMOTE
HEADER="TIME  : $time $( date )\nDATA  : $REMOTE"

# LOCK COMMAND: WIFI TURNED OFF (SECURED)
if [ "$REMOTE" == "1C0#210000900000" ] ; then
  if [ "$REMOTE" != "$LASTREMOTE" ] ; then
    [ $DEBUG == "true" ] && echo -e $HEADER
    [ $DEBUG == "true" ] && echo "EVENT : KEYFOB LOCK COMMAND RECEIVED"
    [ $DEBUG == "true" ] && echo "ACTION: TURNING OFF WIFI DEVICE"

    # DISABLING WIFI TRANSMITTER

    ifconfig $WIFIDEV down
    sleep 2
    iwconfig $WIFIDEV txpower off

    [ $DEBUG == "true" ] && echo ""

  fi
fi

# 1ST UNLOCK COMMAND: NO ACTION TAKEN
if [ $REMOTE == "1C0#230000900000" ] ; then
  if [ "$REMOTE" != "$LASTREMOTE" ] ; then
    [ $DEBUG == "true" ] && echo -e $HEADER
    [ $DEBUG == "true" ] && echo "EVENT : KEYFOB 1ST UNLOCK COMMAND RECEIVED"
    [ $DEBUG == "true" ] && echo "ACTION: NONE"
    [ $DEBUG == "true" ] && echo ""
  fi
fi

# 2ND UNLOCK COMMAND: WIFI TURNED ON (LESS SECURED)
if [ $REMOTE == "1C0#240000900000" ] ; then
  if [ "$REMOTE" != "$LASTREMOTE" ] ; then
    [ $DEBUG == "true" ] && echo -e $HEADER
    [ $DEBUG == "true" ] && echo "EVENT : KEYFOB 2ND UNLOCK COMMAND RECEIVED"
    [ $DEBUG == "true" ] && echo "ACTION: TURNING ON WIFI DEVICE"

    # ENABLING WIFI TRANSMITTER
    # All commands appear to be necessary even if they return errors.
    # Use extreme care when editing the following section.

    iwconfig $WIFIDEV txpower on
    sleep 4
    iwconfig $WIFIDEV txpower auto
    sleep 1
    ifconfig $WIFIDEV up

    [ $DEBUG == "true" ] && echo ""

  fi
fi

# IDLE (NO COMMANDS): NO ACTION
if [ $REMOTE == "1C0#000000800000" ] ; then
  if [ "$REMOTE" != "$LASTREMOTE" ] ; then
    [ $DEBUG == "true" ] && echo -e $HEADER
    [ $DEBUG == "true" ] && echo "EVENT : IDLE STATE (DEFAULT) HAS RESUMED"
    [ $DEBUG == "true" ] && echo "ACTION: NO ACTION IS NECESSARY"
    [ $DEBUG == "true" ] && echo ""
  fi
fi

# KEEP TRACK OF WHAT THE PREVIOUS COMMAND WAS.
# THIS MAY BE USEFUL TO TRACK WHEN MONITORING OTHER CAN BUS IDs.
LASTREMOTE=$REMOTE

done