#!/bin/sh

. /lib/blue-merle/functions.sh

if [ ! -c "/dev/ttyUSB3" ]; then
	echo "Error: /dev/ttyUSB3 does not exist."
	echo "Please reboot and contact the maintainer if the problem persists."
	exit 1;
fi

echo -n "Swap SIM card and update IMEI? (Y/n): "
read answer
case $answer in
	n*) answer=0;;
	N*) answer=0;;
	*) answer=1;;
esac
if [[ "$answer" -eq 0 ]]; then
	exit 1;
fi


echo "Disabling the ME from both transmitting and receiving RF signals..."

old_imei=$(READ_IMEI)
old_imsi=$(READ_IMSI)

answer=1
while [[ "$answer" -eq 1 ]]; do
	gl_modem AT AT+CFUN=4 | grep -q OK
	if [[ $? -eq 1 ]]; then
		echo -n "...failed. Try again? (Y/n): "
		read answer
		case $answer in
			n*) answer=0;;
			N*) answer=0;;
			*) answer=1;;
		esac
		if [[ $answer -eq 0 ]]; then
			exit 1
		fi
	else
		answer=0
	fi
done

## We have just disabled the modem so it should not log on to any network.
## We set a random IMEI now only to have it overwritten very soon after
## the SIM card has been replaced. We intend to prevent an accidential
## leak of the new SIM's IMSI with the old IMEI just in case the modem
## accidentally tried to log in to the network.
python3 /lib/blue-merle/imei_generate.py -r


echo -n "Please now replace the SIM card and press any key to continue. "
read answer

leak=0

until gl_modem AT AT+CFUN=0 | grep -q OK
do
	sleep 1
	echo "CFUN=0 failed. Trying again."
done

until gl_modem AT AT+CFUN=4 | grep -q OK
do
	leak=1
	echo "CFUN=4 failed. Trying again."
done

if [[ $leak -eq 1 ]]; then
	echo
	echo "WARNING: Reset took longer than expected."
	echo
fi

sleep 1

new_imsi=$(READ_IMSI)

if [[ "$old_imsi" == "$new_imsi" ]]; then
	echo
	echo "WARNING: Old IMSI equals new IMSI."
	echo
fi

echo -n "Would you like to set a random (r) or deterministic (d) IMEI? (R/d): " 
read answer                                      
case $answer in                                  
        d*) answer=0;;
        D*) answer=0;;
        *) answer=1;;
esac                                            
if [[ "$answer" -eq 1 ]]; then                  
	python3 /lib/blue-merle/imei_generate.py -r
else
	python3 /lib/blue-merle/imei_generate.py -d
fi   

new_imei=$(READ_IMEI)

if [[ "$old_imei" == "$new_imei" ]]; then
	echo
	echo "WARNING: Old IMEI equals new IMEI."
	echo
else
	mkdir -p /tmp/modem.1-1.2
	echo "$new_imei" > /tmp/modem.1-1.2/modem-imei
fi

echo "You should now reset the modem or shutdown the device."
echo "For extra privacy, you should shutdown the device and change your location."
echo
echo -n "Would you like to shutdown the device (s) or reset the modem (m)? (S/m): "
read answer
case $answer in
	m*) answer=0;;
	M*) answer=0;;
	*) answer=1;;
esac
if [[ "$answer" -eq 1 ]]; then
    echo '{ "msg": "Shutting down..." }' > /dev/ttyS0
    echo '{ "poweroff": "1" }' > /dev/ttyS0
else
	echo "Resetting modem..."
	until gl_modem AT AT+QPOWD | grep -q OK
	do
		echo "Resetting modem failed. Trying again."
		sleep 1
	done 
	
	time_start=$(date +%s)
	until imsi=$(gl_modem AT AT+CIMI | grep -w -E "[0-9]{6,15}")
	do
		time_now=$(date +%s)
		echo -ne "Waiting for reset to complete. ($(($time_now-$time_start))s/30s)\r"
		sleep 1
	done
	echo
	echo "FIN"
fi