#! /bin/bash
#
#	$Id$
#	http://www.jankratochvil.net/project/line9k/
#	Modem / Nokia 9110 incoming GSM data gate
#
#	/etc/ppp/chap-secrets:
#		Secrets for authentication using CHAP
#		client		server	secret		IP addresses
#		username1a	line9k	secret1a	192.168.90.11
#		username1b	line9k	secret1b	192.168.90.11
#		username2	linecr	secret2		192.168.90.12
#
#	/etc/inittab:
#		l9:2345:respawn:/usr/local/sbin/line9k line9k
#		lc:2345:respawn:/usr/local/sbin/line9k linecr
#
#	Charger scheme:
#		              1N4148
#		RS232 DTR------|>|------     --------------+--------------     ----AC conn.
#		                        |   |              |              |   |
#		                        )  /               |   1N4148     )  /
#		                        ) /                 ----|>|----   ) /
#		               680R     ) --                           |  ) --
#		              ______    |   |                          |  |   |
#		RS232 GND----|______|---     ----PS/2 +5V     PS/2 GND-+--     ----AC conn.
#		                     RELSIA05-500                       RAS-0515
#
#	Manual charge control:
#		/usr/local/sbin/line9k charge on	# Force charging on
#		/usr/local/sbin/line9k charge off	# Automatic charging
#		/usr/local/sbin/line9k charge		# Query charging force


device=$1

# Local IP address of setup pointtopoint interfaces
LOCAL_IP=192.168.90.10

# Nameserver for remote clients:
NS=192.168.90.10

# Percent of battery where charging starts
charge_force_le=50;

# Charger control port
charge_ttyS=/dev/ttyS0

# Time in seconds to charge the battery after reaching 100% state
max_limit_time=$[3*60*60];

case $device in
	line9k)
		PORT=/dev/ttyS4	# 9110
		BAUD=19200
		# Local IP address of setup pointtopoint interfaces
		REMOTE_IP=192.168.90.11
		RINGS=1
		OPTIONS="-crtscts xonxoff asyncmap a0000"
		# "server" field in /etc/ppp/chap-secrets
		AUTH_NAME=line9k
		CHARGE=true
		;;
	linecr)
		PORT=/dev/ttyS3	# Courier
		BAUD=57600
		REMOTE_IP=192.168.90.12
		RINGS=7
		OPTIONS="crtscts asyncmap 0"
		AUTH_NAME=linecr
		CHARGE=false
		;;

##############################################################################
# Configuration section ends here.
##############################################################################

	charge)
		function chargestate
		{
			echo -n "Charging force: "
			if test -f $charge_ttyS.charge;then
				echo "YES"
			else
				echo "NO"
				fi
		}
		chargestate
		if [ "$2" = on -o "$2" = yes ];then
			echo "CHANGED: YES"
			touch $charge_ttyS.charge
			baud=9600
		elif [ "$2" = off -o "$2" = no ];then
			echo "CHANGED: NO"
			rm -f $charge_ttyS.charge
			baud=0
			fi
		stty -F $charge_ttyS -hup clocal $baud 2>/dev/null
		[ -n "$2" ] && chargestate
		exit 0
		;;
	*)
		echo "Unknown device: $device"
		exit 1
	esac

RING1='"RING" "\c"'
RINGSTR=""
while [ $RINGS -gt 0 ];do
	# FIXME: timeout is not reset after stray ring(s)
	RINGSTR="$RINGSTR $RING1"
	RINGS=$[$RINGS-1]
	done
LOGGER="logger -i -t $device"

# Use single AT/OK after ATZ to set terminal speed for USRobotics Courier
exec pppd "$PORT" "$BAUD" modem lock $OPTIONS $LOCAL_IP:$REMOTE_IP ms-dns "$NS" \
	connect '
		charge_val_last=-1;
		baud_last=0;
		limit_date_last=0;
		aborts='\''
			ABORT       "ERROR"
			ABORT       "BUSY"
			ABORT       "NO\sANSWER"
			ABORT       "NO\sCARRIER"
			ABORT       "NO\sDIAL\sTONE"
			ABORT       "VOICE"
			'\'';
		rc=3;
		while test $rc -eq 3; do
		chat                          \
			TIMEOUT     1         \
			""          "ATZ"     \
			"OK-ATZ-OK" "AT"      \
			ABORT       "+CBC: 0,0"   \
			ABORT       "+CBC: 0,25"  \
			ABORT       "+CBC: 0,50"  \
			ABORT       "+CBC: 0,75"  \
			ABORT       "+CBC: 0,100" \
			"OK"                  \
				'"`if $CHARGE;then echo "AT+CBC" NOTREACHED;fi`"' \
			            "\c"      \
			;
		rc=$?; test $rc -eq 0 -o $rc -ge 4 || exit $rc;
		if '$CHARGE';then
			charge_arr=(0 25 50 75 100);
			charge_val=${charge_arr[$[$rc-4]]};
			charge_force_le='$charge_force_le';
			charge_limit_gt=99;
			max_limit_time='$max_limit_time';
			baud=$baud_last;
			charge_ttyS='$charge_ttyS';
			if test -f $charge_ttyS.charge;then
				baud=nocontrol;
			else
				if test $baud = nocontrol;then
					baud=0;
					fi;
				if test $charge_val -le $charge_force_le;then baud=9600;fi;
				if test $charge_val -gt $charge_limit_gt;then
					limit_date=$[`date +%s`];
					if test $limit_date_last -eq 0;then
						limit_date_last=$limit_date;
						if test $baud -ne 0;then
							'"$LOGGER"' "CHARGE state: full-stage charging entered";
							fi;
					else
						if test $baud -ne 0 -a $[$limit_date-$limit_date_last] -gt $max_limit_time;then
							'"$LOGGER"' "CHARGE state: full-stage charging terminated";
							baud=0;
							fi;
						fi;
				else
					limit_date_last=0;
					fi;
				fi;
			if test $charge_val_last -ne $charge_val -o $baud_last '!=' $baud;then
				'"$LOGGER"' "CHARGE state: charge=$charge_val; baud=$baud";
				fi;
			charge_val_last=$charge_val;
			baud_last=$baud;
			if test $baud '!=' nocontrol;then
				stty -F $charge_ttyS -hup clocal $baud 2>/dev/null;
				fi;
			fi;
		chat                          \
			$aborts               \
			TIMEOUT     590       \
			'"$RINGSTR"'          \
			;
		rc=$?; test $rc -eq 0 -o $rc -eq 3 || exit $rc;
		done
		chat -v $aborts               \
			TIMEOUT     40        \
			REPORT      "CONNECT" \
			""          "ATA"     \
			"CONNECT"   "\c"      \
			"^M"        "\c"      \
			;
		rc=$?; test $rc -eq 0 || exit $rc;
		baud=9600;
		stty -F $charge_ttyS -hup clocal $baud 2>/dev/null;
		' \
	-ccp nodefaultroute lcp-echo-interval 30 lcp-echo-failure 4 lcp-max-configure 30 -detach debug nologfd kdebug 255 \
	require-chap -pap auth name $AUTH_NAME