#!/bin/sh
#
# Author: Petter Reinholdtsen

set -e

daylimit=120
makewebreport=/usr/sbin/sitesummary-makewebreport
nodes=/usr/sbin/sitesummary-nodes
nagiosopts=-r

# Modify this in collector.cfg to /etc/munin/ to automatically replace
# the default munin configuration.
MUNINDIR=/var/lib/sitesummary

# Specifies where to save the automatically generated nagios
# configuration.  Add NAGIOSCFG="/etc/nagios3/sitesummary.cfg" to
# /etc/default/nagios3 toget Nagios to use this automatically
# generated configuration
NAGIOSDIR=/var/lib/sitesummary

[ -f /etc/sitesummary/collector.cfg ] && . /etc/sitesummary/collector.cfg

# Exit imediately if the package is removed but nor purged
if [ ! -x $nodes ] ; then
    exit 0
fi

# The storage area is not configurable, because too many scripts have
# it hardcoded
entriesdir=/var/lib/sitesummary/entries

remove_old_entries() {
    find $entriesdir/. -mindepth 1 -maxdepth 1 -type d \
	-daystart -mtime +$daylimit \
	-exec /usr/lib/sitesummary/expire-entry '{}' \;
}

generate_munin_config() {
    # Generate munin config.  Edit /etc/cron.d/munin to enable it.
    # Add -c /var/lib/sitesummary/sitesummary-munin.conf to the calls
    # to the munin scripts, or change MUNINDIR above.
    (
	if [ -f $MUNINDIR/munin.conf.pre ] ; then
	    cat $MUNINDIR/munin.conf.pre
	else
	    # Copy of active config from munin version 1.2.5-1
	    cat <<EOF
# Munin server configuration generated from cron using sitesummary
# data by $0
# Do not edit, it will be overwritten. 
# Edit $MUNINDIR/munin.conf.pre and
# $MUNINDIR/munin.conf.post instead.

dbdir	/var/lib/munin
htmldir	/var/www/munin
logdir	/var/log/munin
rundir	/var/run/munin
tmpldir	/etc/munin/templates

EOF
	fi

	sitesummary-nodes -m

	[ -f $MUNINDIR/munin.conf.post ] && cat $MUNINDIR/munin.conf.post

        # Make sure the subshell return true to trigger the mv below.
	true
    ) > $MUNINDIR/munin.conf.new && \
	chown root:root $MUNINDIR/munin.conf.new && \
	chmod a+r $MUNINDIR/munin.conf.new && \
	mv $MUNINDIR/munin.conf.new $MUNINDIR/munin.conf
}

generate_nagios_config() {
    (
	sitesummary-nodes -n $nagiosopts

	if [ -f $NAGIOSDIR/nagios-generated.cfg.post ] ; then
	    cat $NAGIOSDIR/nagios-generated.cfg.post
	fi

	true
    ) > $NAGIOSDIR/nagios-generated.cfg.new && \
        chmod a+r $NAGIOSDIR/nagios-generated.cfg.new
    if cmp -s $NAGIOSDIR/nagios-generated.cfg.new $NAGIOSDIR/nagios-generated.cfg
    then
	rm $NAGIOSDIR/nagios-generated.cfg.new
	false
    else
        mv $NAGIOSDIR/nagios-generated.cfg.new $NAGIOSDIR/nagios-generated.cfg
	true
    fi
}

# Only enable if munin and sitesummary is installed.
if [ -f /etc/munin/munin.conf ] && [ -x /usr/sbin/sitesummary-nodes ]; then
    generate_munin_config
fi

# Only enable if nagios v3 and sitesummary is installed.
if [ -f /etc/init.d/nagios3 ] && [ -x /usr/sbin/sitesummary-nodes ]; then
    # Only reload nagios if the configuration changed
    if generate_nagios_config ; then
    # subshell to avoid passing all variables from
    # /etc/default/nagios3 to other parts of this script
    (
	if [ -r /etc/default/nagios3 ] ; then
	    . /etc/default/nagios3
	fi
	# Only reload nagios if the sitesummary config is the active
	# one and nagios3 is currently running.
	if [ /etc/nagios3/sitesummary.cfg = "$NAGIOSCFG" ] && \
	    invoke-rc.d nagios3 status >/dev/null ; then
	    invoke-rc.d nagios3 reload >/dev/null
	fi
    )
    fi
fi

[ -d $entriesdir ] && remove_old_entries

# Update the web report once a day
[ -x $makewebreport ] && nice $makewebreport