#!/bin/bash

LOCKFILE="/var/run/sync-mirrors/lockfile"
LOGFILE="/var/log/sync-mirrors/sync-mirrors-$(date +%Y%m%d%H%M%S).log"
CONFDIR="/etc/sync-mirrors"

usage() {
    echo "Usage: $(basename "$0") [-v] [mirror]" 1>&2
    echo "       $(basename "$0") -l" 1>&2
}

logmsg() {
    [ "${VERBOSE}" -eq 1 ] && echo "$1"
    echo "$(date '+%Y/%m/%d %H:%M:%S') [$$] $1" >> "${LOGFILE}"
}

if [ -d ${CONFDIR} ]; then
    MIRRORLIST="$(find ${CONFDIR}/ -name \*.conf | while read f ; \
        do basename "${f}" | sed -e 's/\.conf$//' ; done)"
    if [ "${MIRRORLIST}" = "" ]; then
        echo "ERR: No configured mirrors found" 1>&2
        exit 1
    fi
else
    echo "ERR: Config directory [${CONFDIR}] missing" 1>&2
    exit 1
fi

VERBOSE=0
NOOP=""
EXTRA_OPTS=""
while getopts "vhln" c ; do
    case $c in
	v)
	    VERBOSE=1
	    EXTRA_OPTS="${EXTRA_OPTS} -v --progress"
	    ;;
	h)
	    usage
	    exit 1
	    ;;
	l)
	    echo "Available mirrors:"
            for name in ${MIRRORLIST} ; do
		echo "  ${name}"
	    done
	    exit 0
	    ;;
        n)
            NOOP=" (DRY RUN)"
            EXTRA_OPTS="${EXTRA_OPTS} -n"
            ;;
        *)
            usage
            exit 1
            ;;
    esac
done

shift "$((OPTIND - 1))"

if [ $# -gt 0 ]; then
    for mirror in "$@" ; do
        if [ ! -f "${CONFDIR}/$1.conf" ]; then
            echo "ERR: No mirror named [$1]" 1>&2
            exit 1
        fi
        SYNC="${MIRRORS} $1"
        shift
    done
else
    SYNC="${MIRRORLIST}"
fi

if [ "$(whoami)" != "mirror" ]; then
    echo "ERR: Script needs to be run as mirror user" 1>&2
    exit 1
fi

umask 022

if [ -f "${LOCKFILE}" ]; then
    kill -0 "$(cat ${LOCKFILE})"
    if [ $? -ne 1 ]; then
	which stat > /dev/null 2>&1
	if [ $? -eq 0 ]; then
	    STARTED=" ($(stat --format='%y' ${LOCKFILE}))"
	else
	    STARTED=""
	fi
        echo "ERR: Lockfile exists${STARTED}, exiting" 1>&2
        exit 1
    else
        echo "WARN: Removing stale lock file..." 1>&2
        rm -f "${LOCKFILE}"
    fi
fi
trap 'rm -f ${LOCKFILE}' INT TERM EXIT
echo "$$" > "${LOCKFILE}"

for mirror in ${SYNC} ; do
    POSTCMD=""
    SRC=""
    RSYNCOPTS=""
    . "${CONFDIR}/${mirror}.conf"
    if [ "${SRC}" = "" ]; then
        echo "ERR: No SRC set for mirror ${mirror} ..." 1>&2
        exit 1
    fi
    logmsg "Starting ${mirror} sync${NOOP}..."
    rsync -aH -4 ${EXTRA_OPTS} --numeric-ids --delete --delete-delay \
        --delay-updates --no-motd ${RSYNCOPTS} --log-file="${LOGFILE}" \
        --exclude=.~tmp~/ "${SRC}" "/srv/mirrors/${mirror}/"
    STATUS=$?
    if [ ${STATUS} -ne 0 ]; then
        echo "WARN: Encountered errors on ${mirror} sync, see ${LOGFILE} for details" 1>&2
    fi
    logmsg "Finished ${mirror} sync with exit status ${STATUS}${NOOP} ..."
    if [ "${POSTCMD}" != "" ]; then
        logmsg "Running post for ${mirror} ..."
        ${POSTCMD} 2>&1 | awk \
           "{ print strftime(\"%Y/%m/%d %H:%M:%S\") \" [$$] \" \$0 }" \
           >> "${LOGFILE}"
        logmsg "Finished post for ${mirror} ..."
    fi
done

rm -f "${LOCKFILE}"