#!/bin/bash
#########################################################################################
#
# filename:		txfan
#
# description:		This file controls a PC fan attached to any aux port.  It starts up when
#			PTT is detected, and will stay on for the time period specified in
#			the TIMEAFTER variable after the PTT drops.  If the PTT is triggered
#			in the countdown period, the timer resets.
#
# original authors:     The majority of this script (the state manager) was taken from 
#                       the ID scripts by KC6HUR and WW4M.
#
#                       Add the following to the events stanza of rpt.conf for each node you want
#                       controlled by the fan. Multiple nodes can control a single fan. The Event Management 
#                       Subsystem is used to indicate PTT state to the txfan process.
#
#                       touch /dev/shm/~pttstate = s|t|RPT_TXKEYED
#                       rm -f /dev/shm/~pttstate = s|f|RPT_TXKEYED
#
#                       Default location for this txfan script is /etc/asterisk
#
#			Add the following code snipit near the end of /etc/rc.local
#			This will restart TXFAN process each time the node is restarted.
#
#                       CUSTOM=/etc/asterisk
#			if [ -f $CUSTOM/txfan ] ; then
#			  echo -n "Starting TXFAN process..."
#			  killall txfan &>/dev/null
#			  /bin/su - -c $CUSTOM/txfan root &>/dev/null &
#			  echo "done!"
#			fi
#
# history:
# 2005-02-16    kd6hwc  Initial creation (with help from other scripts)
# 2007-07-29	k6jwn	Added new variable PTTON, fan won't come on until this timer reaches
#			it's limit.
# 2012-01-28    k0kn    Adapted script for app_rpt system
# 2015-09-07    k0kn    Feature add for external commands during fan on/off
# 2015-12-02    k0kn    PiGpio pin support added
#########################################################################################

# Temp file that exists when PTT active
PTTSTATE="/dev/shm/~pttstate"

# Define the AUX Switch that the fan is connected to
#

# Pi_gpio pin 3
FANON="gpio -g write 3 1"
#
FANOFF="gpio -g write 3 0"

# For parallel port pin 4
# FANON="/home/kyle/aux 2211 4 1"
#
# FANOFF="/home/kyle/aux 2211 4 0"
#
# For GPIO pin 1
# FANON="/home/kyle/gpio 2211 1 1"
# FANOFF="/home/kyle/gpio 2211 1 0"

# Define external commands when fan turns on/off
FANON_CMD="ln -f -s /etc/asterisk/sounds/fan_on.wav /home/kyle/fan.wav"
FANOFF_CMD="ln -f -s /etc/asterisk/sounds/fan_off.wav /home/kyle/fan.wav"

# Define the period of time after the PTT drops to shut off the fan
TIMEAFTER=300

# Define the max PTT time before the fan is activated
PTTON=10

# define variables
declare -i IDLETIMER
declare -i PTTKEY

# Start with state set to "Initial"

STATE="Initial"

while [ TRUE ]
do

case "$STATE" in


	"Initial")      # Wait for first keyup, then proceed to Countdown

		echo -en "\r"`date ` "STATE = Initial\n"
		sleep 1;
		PTTKEY=0

		while [ TRUE ]
		do
			echo -en "\rPTT Timer: $PTTKEY    "
			sleep 1;

			# while PTT is silent (PTT=T)
			if [ -f $PTTSTATE ] ; then
				PTTKEY=$PTTKEY+1
			fi

			if ! [ -f $PTTSTATE ] ; then
				PTTKEY=0
			fi

			if [ $PTTKEY -gt $PTTON ] ; then
				break
			fi
		done
			echo -en "\nPTT timer expired, activating fan"
			$FANON
                        eval $FANON_CMD
                        STATE="Countdown"
	;;


        "Countdown")      # Count down period, if PTT is triggered, reset the timer.

                echo -en "\n\n"`date ` "STATE = Countdown\n"
                sleep 1
                IDLETIMER=$TIMEAFTER

                while [ TRUE ]
                do
                        echo -en "\rFan powerdown timer: $IDLETIMER    "
                        IDLETIMER=$IDLETIMER-1
                        sleep 1

			if [ -f  $PTTSTATE ]
                        then
			  IDLETIMER=$TIMEAFTER
			fi

                        if [ $IDLETIMER = 0 ]
                        then
                                break
                        fi
		done

		echo -en "\nTimer expired, deactivating fan"
		$FANOFF
                eval $FANOFF_CMD
                STATE=Initial
	;;

	esac
done

echo -e "\n\nOops! - Not supposed to get to here"

########################