#!/bin/sh
#------------------------------------------------------------------------------
# =========                 |
# \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
#  \\    /   O peration     |
#   \\  /    A nd           | Copyright (C) 2011-2014 OpenFOAM Foundation
#    \\/     M anipulation  |
#-------------------------------------------------------------------------------
# License
#     This file is part of OpenFOAM.
#
#     OpenFOAM 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.
#
#     OpenFOAM 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 OpenFOAM.  If not, see <http://www.gnu.org/licenses/>.
#
# Script
#     foamEndJob
#
# Description
#     Ends running job on current machine. Called with root,case,pid.
#     - checks if pid exists
#     - modifies controlDict
#     - waits until
#       - pid disappeared
#       - controlDict modified
#       to restore controlDict
#
#-------------------------------------------------------------------------------
Script=${0##*/}

usage() {
    exec 1>&2
    while [ "$#" -ge 1 ]; do echo "$1"; shift; done
    cat<<USAGE
Usage: $Script [OPTION] <pid>
Usage: $Script [OPTION] -c

options:
  -clear            clear any outstanding $Script for the case
  -case <dir>       specify alternative case directory, default is the cwd
  -now              stop at next time step
  -help             print the usage

Tries to end running OpenFOAM application at next write (or optionally
at the next time step). It needs runTimeModifiable switched on in the
controlDict. It changes stopAt in the controlDict and waits for the
job to finish. Restores original controlDict if

    - job has finished
    - controlDict gets modified (by user)
    - $Script gets killed.

The -clear option clears any outstanding $Script for the case.

USAGE
    exit 1
}

unset clearOpt stopOpt

# parse options
while [ "$#" -gt 0 ]
do
    case "$1" in
    -h | -help)
        usage
        ;;
    -case)
        [ "$#" -ge 2 ] || usage "'$1' option requires an argument"
        cd "$2" 2>/dev/null || usage "directory does not exist:  '$2'"
        shift 2
        ;;
    -c | -clear)
        clearOpt=true
        shift
        ;;
    -n | -now)
        stopOpt=now
        shift
        ;;
    -*)
        usage "unknown option: '$*'"
        ;;
    *)
        break
        ;;
    esac
done


# parent directory for normal or parallel
case "$PWD" in
    processor*) caseDir=".." ;;
    *)          caseDir="."  ;;
esac

# check that case directory is writeable
[ -w $caseDir ] || {
    echo "$Script : $caseDir is not writeable"
    exit 1
}

# check that controlDict is writeable
controlDict=$caseDir/system/controlDict
[ -w $controlDict ] || {
    echo "$Script : $controlDict is not writeable"
    exit 1
}

# need a pid unless with the -clear option
if [ "$clearOpt" = true ]
then
    [ $# -eq 0 ] || usage
else
    [ $# -eq 1 ] || usage
    PID=$1
fi


#-------------------------------------------------------------------------------
#
# Functions
#
#-------------------------------------------------------------------------------

# getNumberedLine dictionary entry
# Prints dictionary entry line + lineno
getNumberedLine() {
    grep -n "^[ \t]*$2[ \t]" $1 | grep -v '^//' | head -1
}

# getLine dictionary entry
# Prints dictionary entry line (without lineno)
getLine() {
    getNumberedLine $1 "$2" | sed -e 's/^[^:]*://'
}

# getRawEntry dictionary entry
# Prints value of dictionary entry
getRawEntry() {
    getLine $1 "$2" | sed -e "s/^[ \t]*$2[ \t][ \t]*//"
}

# getEntry dictionary entry
# Like getRawEntry but strips " and ending ';'
getEntry() {
    getRawEntry $1 "$2" | sed -e 's/^"//'  -e 's/;$//' -e 's/"$//'
}

# getKey entryLine
# Prints first item on line
getKey() {
    echo "$1" | sed -e 's/[ \t]*\(.*\)[ \t].*/\1/'
}


# setRawEntry dictionary entry newValue
# Replaces value of entry
setRawEntry() {
    oldNumLine=`getNumberedLine $1 "$2"`
    lineNo=`echo "$oldNumLine" | sed -e 's/:.*//'`
    oldLine=`echo "$oldNumLine" | sed -e 's/^[^:]*://'`
    oldKey=`getKey "$oldLine"`
    oldVal=`getRawEntry $1 "$2"`

    if [ ! "$oldKey" -o ! "$oldVal" -o ! "$oldLine" ]
    then
        echo "setRawStringEntry: entry $2 not found in $1"
        echo "oldKey=$oldKey"
        echo "lineNo=$lineNo"
        echo "oldLine=$oldLine"
        exit 1
    fi

    #echo "oldKey=$oldKey"
    #echo "lineNo=$lineNo"
    #echo "oldLine=$oldLine"
    #echo "oldVal=$oldVal"
    mv $1 ${1}_tmp
    sed -e "${lineNo}s/ ${oldVal}/ $3;/" ${1}_tmp > $1
    rm -f ${1}_tmp
}



# like getEntry but returns true if boolean is logical true
getBoolEntry()
{
    val=`getEntry $1 $2`
    case "$val" in
    y | yes | true | on | 1)
        return 0
        ;;
    n | no | false | off | 0)
        return 123
        ;;
    *)
        echo "$Script : getBoolEntry : Illegal boolean value $val in dictionary $1"
        exit 1
        ;;
    esac
}

# processExists pid
# Returns true if pid exists.
processExists() {
    ps -u $LOGNAME -o pid | fgrep $1 >/dev/null
}

# Restore controlDict and clean up
restoreDict() {
    trap QUIT TERM INT

    echo "$Script : Restoring controlDict from controlDict_bak"
    if [ -r ${controlDict}_bak ]
    then
        cp ${controlDict}_bak $controlDict
    fi

    rm -f $pidFile

    echo "$Script : Exiting"
    exit 0
}


#-------------------------------------------------------------------------------
#
# Main
#
#-------------------------------------------------------------------------------

#-- Force standards behaving ps
#   Get info on all $USER processes
case `uname -s` in
HP-UX*)
    UNIX95=a
    export UNIX95
    ;;
IRIX*)
    _XPG=1
    export _XPG
    ;;
esac


# Pid actually running
if [ "$clearOpt" != true ]
then
    processExists $PID
    if [ $? -ne 0 ]
    then
        echo "$Script : process $PID not running"
        exit 1
    fi
fi

#- runTimeModifiable
getBoolEntry $controlDict runTimeModifiable || {
    echo "$Script : runTimeModifiable not true in dictionary $controlDict"
    exit 1
}

#
#- Check if another foamEndJob running
#
if [ "$clear" = true ]
then
    pidFiles=`ls $caseDir/.foamEndJob* 2>/dev/null`
    for pidFile in $pidFiles
    do
        pid=`cat $pidFile`
        if [ "$pid" ]
        then
            echo "$Script : found $Script (pid $pid) for OpenFOAM process"
            echo "  case: $PWD/$caseDir"
            echo "$Script : Killing $Script (pid $pid)"
            kill $pid
            rm -f $pidFile
        fi
    done
    exit 0
fi

pidFile=$caseDir/.foamEndJob$PID
if [ -f $pidFile ]
then
    pid=`cat $pidFile`
    if [ "$pid" ]
    then
        processExists $pid
        if [ $? -eq 0 ]
        then
            echo "$Script : found running $Script (pid $pid) for OpenFOAM process"
            echo "  case: $PWD/$caseDir"
            echo "  pid : $PID"
            echo "  lock: $pidFile"
            echo "Remove the lock if this is not the case"
            exit 1
        fi
    fi
fi

# Mark with my pid
echo $$ > $pidFile

#
#- Get controlDict entries
#


#- startTime
startTime=`getEntry $controlDict startTime`
[ "$startTime" ] || {
    echo "$Script : startTime not set in dictionary $controlDict"
    exit 1
}

#- Write interval
writeInterval=`getEntry $controlDict writeInterval`
[ "$writeInterval" ] || {
    echo "$Script : writeInterval not set in dictionary $controlDict"
    exit 1
}

#- stopAt
stopAt=`getEntry $controlDict stopAt`
[ "$stopAt" ] || {
    echo "$Script : stopAt not set in dictionary $controlDict"
    exit 1
}

#- endTime
endTime=`getEntry $controlDict endTime`
[ "$endTime" ] || {
    echo "$Script : endTime not set in dictionary $controlDict"
    exit 1
}


echo "$Script : Read from controlDict:"
echo "  controlDict   : $controlDict"
echo "  writeInterval : $writeInterval"
#echo "  startTime     : $startTime"
echo "  stopAt        : $stopAt"
#echo "  endTime       : $endTime"

echo "$Script : Making backup of controlDict to controlDict_bak"
cp $controlDict ${controlDict}_bak

#- Set up handler to restore controlDict
trap restoreDict QUIT TERM INT

if [ "$stopOpt" = now ]
then
    setRawEntry  $controlDict stopAt nextWrite
    setRawEntry  $controlDict writeControl timeStep
    setRawEntry  $controlDict writeInterval 1

    echo "$Script : Changed in controlDict:"
    echo "    `getLine $controlDict stopAt`"
    echo "    `getLine $controlDict writeControl`"
    echo "    `getLine $controlDict writeInterval`"
else
    setRawEntry $controlDict stopAt nextWrite

    echo "$Script : Changed in controlDict:"
    echo "    `getLine $controlDict stopAt`"
fi



#- Just to make sure time has changed
touch ${controlDict}

sleep 5

#- Give bak a later date
touch ${controlDict}_bak

#- Loop a while to give NFS time to update
if [ ${controlDict} -nt ${controlDict}_bak ]
then
    echo "$Script : controlDict newer than controlDict_bak"
    echo "$Script : Waiting for file dates to get updated"

    iter=0
    while [ ${controlDict} -nt ${controlDict}_bak ]
    do
        if [ $iter -ge 120 ]
        then
            #- 120*5 sec = 10 mins passed. Give up
            echo "$Script : File date not yet ok after 10 mins ... giving up"
            break
        fi
        #- Give _bak a later time
        touch ${controlDict}_bak

        #- Give NFS a chance to update time on controlDict.
        sleep 5

        iter=`expr $iter + 1`
    done
fi

#
#- Start waiting until:
#  - pid finished. Restore controlDict.
#  - controlDict modified. No restore.
#  - controlDict_bak removed. No restore.

echo "$Script : Waiting for OpenFOAM job $PID to finish ..."

while true
do
    sleep 5

    [ -r ${controlDict}_bak ] || {
        echo "$Script : ${controlDict}_bak disappeared. Exiting without restore"
        exit 1
    }

    if [ ${controlDict} -nt ${controlDict}_bak ]
    then
        echo "$Script : ${controlDict} modified externally. Exiting without restore"
        exit 0
    fi

    processExists $PID
    if [ $? -ne 0 ]
    then
        #- Job finished
        break
    fi
    # echo "OpenFOAM job $PID still running ..."
done

#- Dictionary restore
restoreDict

#------------------------------------------------------------------------------