#!/bin/sh
#------------------------------------------------------------------------------
# =========                 |
# \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
#  \\    /   O peration     |
#   \\  /    A nd           | Copyright (C) 2011 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
#     foamJob
#
# Description
#     Run an OpenFOAM job in background.
#     Redirects the output to 'log' in the case directory.
#
#------------------------------------------------------------------------------
usage() {
    exec 1>&2
    while [ "$#" -ge 1 ]; do echo "$1"; shift; done
    cat<<USAGE

Usage: ${0##*/} [OPTION] <application> ...
options:
  -case <dir>       specify alternative case directory, default is the cwd
  -parallel         parallel run of processors
  -screen           also sends output to screen
  -version <ver>    specify an alternative OpenFOAM version
  -help             print the usage

* run an OpenFOAM job in background.
  Redirects the output to 'log' in the case directory

USAGE
    exit 1
}

unset version

# replacement for possibly buggy 'which'
findExec() {
    case "$1" in
    */*)
        if [ -x "$1" ]
        then
            echo "$1"
            return 0
        fi
        ;;
    esac

    oldIFS=$IFS
    IFS=':'
    for d in $PATH
    do
        # echo "testing: $d/$1" 1>&2
        if [ -x "$d/$1" -a ! -d "$d/$1" ]
        then
            # echo "Found exec: $d/$1" 1>&2
            IFS=$oldIFS
            echo "$d/$1"
            return 0
        fi
     done
     IFS=$oldIFS
     echo ""
     return 1
}



# MAIN SCRIPT
#~~~~~~~~~~~~
unset parallelOpt screenOpt


# 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:  '$2'"
      shift 2
      ;;
   -p | -parallel)
      parallelOpt=true
      shift
      ;;
   -s | -screen)
      screenOpt=true
      shift
      ;;
   -v | -version)
      [ "$#" -ge 2 ] || usage "'$1' option requires an argument"
      version="$2"
      shift 2
      ;;
   --)
      shift
      break
      ;;
   -*)
      usage "invalid option '$1'"
      ;;
   *)
      break
      ;;
   esac
done

[ "$#" -ge 1 ] || usage "No application specified"


# use foamExec for a specified version
# also need foamExec for remote (parallel) runs
if [ -n "$version" -o "$parallelOpt" = true ]
then
    # when possible, determine if application even exists
    if [ -z "$version" ]
    then
        findExec $1 >/dev/null || usage "Application '$1' not found"
    fi

    # use foamExec for dispatching
    APPLICATION=`findExec foamExec` || usage "'foamExec' not found"

    [ -n "$version" ] && APPLICATION="$APPLICATION -version $version"

    # attempt to preserve the installation directory 'FOAM_INST_DIR'
    if [ -d "$FOAM_INST_DIR" ]
    then
        APPLICATION="$APPLICATION -prefix $FOAM_INST_DIR"
    fi

else
    APPLICATION=`findExec $1` || usage "Application '$1' not found"
    echo "Application : $1"
    shift
fi


if [ "$parallelOpt" = true ]
then
    # parallel
    # ~~~~~~~~

    #
    # is the case decomposed?
    #
    if [ -r "processor0" ]
    then
        NPROCS="`/bin/ls -1d processor* | wc -l`"
    else
        echo "Case is not currently decomposed"
        if [ -r system/decomposeParDict ]
        then
            echo "system/decomposeParDict exists"
            echo "Try decomposing with \"foamJob decomposePar\""
            exit 1
        else
            echo "Cannot find system/decomposeParDict file required to decompose the case for parallel running."
            echo "Please consult the User Guide for details of parallel running"
            exit 1
        fi
    fi

    #
    # locate mpirun
    #
    mpirun=`findExec mpirun` || usage "'mpirun' not found"
    mpiopts="-np $NPROCS"

    #
    # is the machine ready to run parallel?
    #
    echo "Parallel processing using $WM_MPLIB with $NPROCS processors"
    case "$WM_MPLIB" in
    *OPENMPI)
        # add hostfile info
        for hostfile in \
            hostfile \
            machines \
            system/hostfile \
            system/machines \
            ;
        do
            if [ -r $hostfile ]
            then
                mpiopts="$mpiopts -hostfile $hostfile"
                break
            fi
        done
        ;;
    esac

    #
    # run (in parallel)
    #
    if [ "$screenOpt" = true ]
    then
        echo "Executing: $mpirun $mpiopts $APPLICATION $@ -parallel | tee log"
        $mpirun $mpiopts $APPLICATION $@ -parallel | tee log
    else
        echo "Executing: $mpirun $mpiopts $APPLICATION $@ -parallel > log 2>&1"
        $mpirun $mpiopts $APPLICATION $@ -parallel > log 2>&1 &
    fi

else
    #
    # run (on single processor)
    #
    if [ "$screenOpt" = true ]
    then
        echo "Executing: $APPLICATION $@ | tee log &"
        $APPLICATION $@ | tee log &
        wait $!
    else
        echo "Executing: $APPLICATION $@ > log 2>&1 &"
        $APPLICATION $@ > log 2>&1 &
    fi
fi

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