#!/bin/sh
#
# ISPManager sendmail to exim convertor.
#
# WARNING: this script will destroy all existing account configuration in
# Exim's configuration directory (passwd, aliases, domains). Do not forget to
# create backups of sensitive data if need.

SENDMAIL_BASEDIR=/etc/mail
EXIM_BASEDIR=/usr/local/etc/exim

# Configurable options ends here.

SRC_VIRTUSERTABLE=${SENDMAIL_BASEDIR}/virtusertable
SRC_ALIASES=${SENDMAIL_BASEDIR}/aliases

PASSWD=${EXIM_BASEDIR}/passwd
ALIASES=${EXIM_BASEDIR}/aliases
DOMAINS=${EXIM_BASEDIR}/domains

for file in ${SRC_VIRTUSERTABLE} ${SRC_ALIASES}; do
	[ -f "${file}" -a -r "${file}" ] && continue
	echo "Can't read file: ${file}."
	echo "Check \${SENDMAIL_BASEDIR} variable."
	exit 1
done

for file in ${PASSWD} ${ALIASES} ${DOMAINS}; do
	touch "${file}" && [ -f "${file}" ] && continue
	echo "Can't read file: ${file}."
	echo "Check \${EXIM_BASEDIR} variable."
	exit 1
done

>${DOMAINS}
grep ^@ ${SRC_VIRTUSERTABLE} |grep -v error: |\
while read line; do
	set -- ${line}

	domain=${1#@}
	redirect=${2#%1@}

	[ -z "${domain}" -o -z "${redirect}" ] && continue

	action=
	[ "${redirect}" = "devnull" ] && { \
		redirect=${domain}; action=/dev/null; }
	
	echo "${domain}:${redirect}:${action}:no" >>${DOMAINS}
done

grep ^@ ${SRC_VIRTUSERTABLE} |grep error: |\
while read line; do
	set -- ${line}

	domain=${1#@}
	redirect=${domain}
	action=

	[ -z "${domain}" ] && continue

	echo "${domain}:${redirect}:${action}:no" >>${DOMAINS}
done

>${ALIASES}
grep ^virtuser ${SRC_ALIASES} |grep @ |\
while read line; do
	set -- ${line}

	virtuser=${1%:}
	aliases=$2

	set -- $(grep ^${virtuser}: /etc/passwd |sed -e 's#:# #g;s#*#_#g')
	
	maildir=$5
	
	[ -z "${maildir}" ] && continue

	email=${maildir##*/}
	domain=${maildir#/*/email/}; domain=${domain%%/*}

	[ -z "${email}" -o -z "${domain}" ] && continue

	aliases=$(echo ${aliases} |sed -e "s#\\${virtuser}#${email}@${domain}#")
	echo "${email}@${domain}:${aliases}:user" >> ${ALIASES}
done

grep -v ^@ ${SRC_VIRTUSERTABLE} |grep -v virtuser_ |grep @ |\
while read line; do
	set -- ${line}

	alias=$1
	mbox=$2

	echo "${alias}:${mbox}:fwd" >> ${ALIASES}
done

>${PASSWD}
grep  -v ^@ ${SRC_VIRTUSERTABLE}  |grep virtuser_ |\
while read line; do
	set -- ${line} ; mbox=$1 virtuser=$2

	set -- $(grep ^${virtuser}: /etc/passwd |sed -e 's#:# #g;s#*#_#g')

	uid=$3
	gid=$4
	maildir=$5

	[ -z "${uid}" -o -z "${gid}" -o -z "${maildir}" ] && continue

	echo "${mbox}:${uid}:${gid}:0:${maildir}:no:" >> ${PASSWD}
done