entrypoint

#!/bin/bash -e
export PASS=${PASS:-RANDOM}
export USER=${USER:-timemachine}
export USERID=${USERID:-1311}
export GROUPID=${GROUPID:-1311}
export TMSIZE=${TMSIZE:-0}
export SHARENAME=${SHARENAME:-Data}

createUser()
{
    if groupadd -g ${GROUPID} timemachine_users; then
        echo "Created group timemachine_users with ${GROUPID}"
    fi
    if [ $PASS == RANDOM ] ; then
        PASS=$(cat /dev/urandom | tr -dc 'a-zA-Z0-9' | fold -w 16 | head -n 1)
    fi
    if useradd -u ${USERID} -g timemachine_users ${USER} ; then
        echo Creating user ${USER} with a samba password of ${PASS}
        printf "$PASS\n$PASS\n" | smbpasswd -s -a ${USER}
    fi
}

backupConfig()
{
    if [ ! -d ${BACKUPDIR} ] ; then
        echo ${BACKUPDIR} not found did you forget to add the volume?
        exit 1
    else
	echo "Granting permissions to ${USER}/${USERID} with  timemachine_users/${GROUPID} on ${BACKUPDIR}"
        chown -R ${USER}:${GROUPID} ${BACKUPDIR}
    fi
}

makeOptions()
{
    TMSIZE=$(($TMSIZE * 1000000))
    sed "s#REPLACE_TM_SIZE#${TMSIZE}#" /tmp/template_quota > ${BACKUPDIR}/.com.apple.TimeMachine.quota.plist
    sed -i "s#REPLACE_SHARENAME#${SHARENAME}#" /etc/samba/smb.conf
}

if [[ -z $1 ]] || [[ ${1:0:1} == '-' ]] ; then
    createUser
    backupConfig
    makeOptions
    exec /usr/sbin/smbd --no-process-group --foreground "$@"
    exec "$@"
fi