#! /bin/bash
#
# Copyright (C) 2010 Q-Leap Networks
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
# Under Debian a copy can be found in /usr/share/common-licenses/GPL-3.

SCRIPTNAME="${0##*/}"
USAGE="usage: ${SCRIPTNAME} [-h] <jobid>"
# where to find the snapshot-reference
snap_ref_file=${HOME}/.qlu/torque/jobid2ompi_snap_ref

force=false

while getopts :hf OPT
do
    case $OPT in
	h)
	    echo "${USAGE}"
	    exit
	    ;;
	f)
	    force=true
	    ;;
	*)
	    echo "${USAGE}" >&2
	    exit 2
    esac
done
shift $[ OPTIND - 1 ]

jobid="$1"

if [ -z "$jobid" ]; then
    echo "${SCRIPTNAME}: parameter <jobid> missing" >&2
    echo "${USAGE}" >&2
    exit 2
fi

function get_snap_entry() {
    local jobid="$1" snap_ref_file="$2"
    if [ ! -f "$snap_ref_file" ]; then
	echo "${FUNCNAME}(): no such file: \"${snap_ref_file}\"" >&2
	return 1
    fi
    if [ -z "$jobid" ]; then
	echo "${FUNCNAME}(): parameter <jobid> missing" >&2
	return 2
    fi
    # take the last match
    # DONE allow only a number as job id
    # if job id consists entirely of numbers
    # then match everything up to the first dot
    awk '{
	    if(jid ~ /^[0-9]*$/) {
		split($1,arr_jid,/\./)
		jid_saved=arr_jid[1]
	    } else {
		jid_saved=$1
	    }
	}
	jid_saved == jid {
	    snap_ref=$0
	} END {
	    print snap_ref
    }' jid="$jobid" \
	"${snap_ref_file}"
}

function get_nodelist() {
    local nodefile="$1"
    if [ ! -f "$nodefile" ]; then
	return 0
    fi
    sort "$nodefile" | uniq -c | awk '{print $1}' | sort -n | \
	uniq -c | awk 'BEGIN{
		    ORS="";
		    firstline=1
		  } {
		    if(firstline){
			firstline=0
		    } else {
			print "+"
		    }
		    print $1 "*" $2;
		  }'
}

snap_entry=$(get_snap_entry "$jobid" "$snap_ref_file")
if [ -z "$snap_entry" ]; then
    echo "${SCRIPTNAME}: no matching snapshot reference for job \"$jobid\"" >&2
    exit 1
fi

snap_ref=$(echo "$snap_entry" | awk '{print $2}')
saved_nodelist=$(echo "$snap_entry" | awk '{print $3}')
nodelist=$(get_nodelist "${PBS_NODEFILE}")
if [ "$saved_nodelist" != "$nodelist" ]; then
    echo "Saved node geometry ($saved_nodelist) differs from current ($nodelist)" >&2
    if $force; then
	echo "Continuing as you request" >&2
    else
	echo "To continue run this script with the option \"-f\"" >&2
	exit 1
    fi
fi

ompi-restart "$snap_ref"