#!/bin/sh

RETRIES=12
POLLING_WAIT=5

# Run only for cellular network interfaces
[ -z "${IF_APN}" ] && exit 0

background_connect() {
        # Ensure ModemManager is running
        killall -0 ModemManager 2>/dev/null || ModemManager --log-file=/dev/null &

        # Wait for modem detection
        while [ "${RETRIES}" -gt "0" ]; do
                mmcli -m 0 > /dev/null 2>&1 && break
                sleep ${POLLING_WAIT}
                RETRIES="$((RETRIES - 1))"
        done

        # Abort if no modem detected
        if [ "$RETRIES" -eq "0" ]; then
                logger -s -p error -t modemmanager "No modem detected";
                exit
        fi

        ARGS="apn=${IF_APN}"
        [ -n "${IF_PIN}" ] && ARGS="${ARGS},pin=${IF_PIN}"

        [ -n "${IF_USER}" ] && ARGS="${ARGS},user=${IF_USER}"
        [ -n "${IF_PASSWORD}" ] && ARGS="${ARGS},password=${IF_PASSWORD}"
        [ -n "${IF_PORT}" ] && ARGS="${ARGS},number=*99#"

        # Enable the modem and connect to provider
        mmcli -m 0 --simple-connect=${ARGS} > /dev/null 2>&1

	# For serial modems, pppd creates the network interface
	# Otherwise, get an IP with udhcpc
	if [ -n "${IF_PORT}" ]; then
		pppd ${IF_PORT} call mm_cellular > /dev/null 2>&1
	else
		udhcpc -q -i ${IFACE}
	fi

	ifconfig ${IFACE} up
}


if [ "$MODE" = "start" ]; then
        background_connect &
elif [ "$MODE" = "stop" ];  then
	# If a call number was used, destroy the network interface
	[ -n "${IF_PORT}" ] && poff mm_cellular

	ifconfig ${IFACE} down

        # Disconnect and disable the modem
        mmcli -m 0 -d > /dev/null 2>&1
fi