#!/bin/sh
#------------------------------------------------------------------------------
# =========                 |
# \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
#  \\    /   O peration     |
#   \\  /    A nd           | www.openfoam.com
#    \\/     M anipulation  |
#------------------------------------------------------------------------------
#     Copyright (C) 2011-2016 OpenFOAM Foundation
#     Copyright (C) 2016-2022 OpenCFD Ltd.
#------------------------------------------------------------------------------
# License
#     This file is part of OpenFOAM, distributed under GPL-3.0-or-later.
#
# Script
#     paraFoam
#
# Description
#     Start paraview with OpenFOAM libraries and reader modules.
#
# Note
#     Combining -block, -vtk, -builtin options with -region option yields
#     undefined behaviour
#
#------------------------------------------------------------------------------
printBuildHelp() {
cat<<HELP_BUILD
Possible way to build supplementary ParaView/OpenFOAM reader modules

    cd \$WM_PROJECT_DIR/modules/visualization/src/paraview-plugins
    ./Allwclean
    ./Allwmake

HELP_BUILD
}

printHelp() {
    cat<<HELP_HEAD

Usage: ${0##*/} [OPTION] [--] [PARAVIEW_OPTION]
options:
  -block            Use blockMesh reader (.blockMesh extension)
  -vtk              Use VTK builtin OpenFOAM reader (.foam extension)
  -case <dir>       Specify alternative case directory, default is the cwd
  -region <name>    Specify alternative mesh region
  -touch            Create the file (eg, .blockMesh, .OpenFOAM, .foam, ...)
  -touch-all        Create .blockMesh, .foam, .OpenFOAM files (for all regions)
HELP_HEAD

if [ -n "$1" ]
then
cat<<HELP_FULL
  -touch-proc       Same as '-touch' but for each processor
  -plugin-path=DIR  Define plugin directory (default: \$PV_PLUGIN_PATH)
  --help            Display ParaView help
  -help-build       Display help for building reader module and exit
HELP_FULL
fi

cat<<HELP_TAIL_COMMON
  -help             Display short help and exit
  -help-full        Display full help and exit

Start paraview with the OpenFOAM libraries and reader modules.
Note that paraview options begin with double dashes.

Uses paraview=$(command -v paraview)

HELP_TAIL_COMMON

if [ -n "$1" ]
then
cat<<HELP_TAIL_FULL
Equivalent options:
  -touch-all     -touchAll
  -vtk           -builtin

HELP_TAIL_FULL
fi

    exit 0  # A clean exit
}

# Report error and exit
die()
{
    exec 1>&2
    echo
    echo "Error encountered:"
    while [ "$#" -ge 1 ]; do echo "    $1"; shift; done
    echo
    echo "See '${0##*/} -help' for usage"
    echo
    exit 1
}

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

# Do a nice exit to give paraview an opportunity to clean up
unset FOAM_ABORT

# Hack: change all locale to 'C' i.e. using '.' for decimal point. This is
# only needed temporarily until paraview is locale aware. (git version is
# already 2010-07)
export LC_ALL=C

# Default reader extension and plugin name
extension=OpenFOAM
plugin=foamReader

# Parse options
unset regionName optTouch
while [ "$#" -gt 0 ]
do
    case "$1" in
    -help-b*)   # Build help
        printBuildHelp
        exit 0
        ;;
    -help-f*)   # Full help
        printHelp -full
        ;;
    -h | -help*) # Short help
        printHelp
        ;;

    -plugin-path=*)
        # Define alternative plugin directory
        pluginPath="${1#*=}"
        if [ -d "$pluginPath" ]
        then
            export PV_PLUGIN_PATH="$pluginPath"
            pluginPath="${pluginPath%/*}"

            # If located in lib/ subdir, include parent in lib-path
            case "$(basename "$pluginPath")" in
            (lib*)
                LD_LIBRARY_PATH="${pluginPath}:$LD_LIBRARY_PATH"
                ;;
            esac
        else
            echo "Ignore bad/invalid plugin-path: $pluginPath" 1>&2
        fi
        unset pluginPath
        ;;

    -block*)  # Silently accepts -blockMesh
        extension=blockMesh
        plugin=blockReader
        ;;
    -vtk | -built*)
        extension=foam
        unset plugin
        ;;
    -case)
        [ "$#" -ge 2 ] || die "'$1' option requires an argument"
        cd "$2" 2>/dev/null || die "directory does not exist: '$2'"
        shift
        ;;
    -region)
        [ "$#" -ge 2 ] || die "'$1' option requires an argument"
        regionName=$2
        shift
        ;;
    -touch)
        optTouch=true
        unset plugin
        ;;
    -touch-all | -touchAll)
        optTouch=all
        unset plugin
        ;;
    -touch-proc*)
        optTouch=processor
        unset plugin
        ;;
    --)
        shift
        break    # Stop here, treat balance as paraview options
        ;;
    --help)      # Emit paraview help directly
        exec paraview "$@"
        echo "Error: could not exec paraview" 1>&2
        exit 1   # This should not have happened
        ;;
    --*)
        break    # Stop here, treat _this_ and balance as paraview options
        ;;
    *)
        die "Unknown option/argument: '$1'"
        ;;
    esac
    shift
done


pluginError="No supplementary ParaView/OpenFOAM reader modules"

if [ -n "$plugin" ]
then
    if [ -d "$PV_PLUGIN_PATH" ]
    then
        # Check if requested reader module exists

        # Check for different names. For example,
        # - ParaFoamReader     = (paraview >= 5.7)
        # - libParaFoamReader  = (paraview < 5.7) and (OPENFOAM > 1912)

        case "$plugin" in
        (blockReader)
            for libName in \
                ParaFoamBlockReader \
                libParaFoamBlockReader \
            ;
            do
                if [ -f "$PV_PLUGIN_PATH/$libName.so" ]
                then
                    unset pluginError
                    break
                fi
            done
            ;;
        (foamReader)
            for libName in \
                ParaFoamReader \
                libParaFoamReader \
            ;
            do
                if [ -f "$PV_PLUGIN_PATH/$libName.so" ]
                then
                    unset pluginError
                    break
                fi
            done
            ;;
        esac

        if [ -z "$pluginError" ]
        then
            # Ensure plugin is also in the lib-path
            LD_LIBRARY_PATH="${PV_PLUGIN_PATH}:$LD_LIBRARY_PATH"
        else
            cat<< NO_PLUGIN 1>&2
$pluginError
    See '${0##*/} -help-build' for more information

NO_PLUGIN
        fi
    else
        echo "Invalid \$PV_PLUGIN_PATH and -plugin-path= not defined" 1>&2
        echo "$pluginError" 1>&2
    fi

    if [ -n "$pluginError" ]
    then
        # Fallback to native reader, if possible
        case "$plugin" in
        (foamReader)
            echo "Using builtin reader: ${0##*/} -vtk" 1>&2
            echo 1>&2
            extension=foam
            ;;
        (*)
            echo 1>&2
            exit 1
            ;;
        esac
        unset plugin
    fi
fi


# Check for --data=... argument
unset hasData
for i
do
    case "$i" in (--data=*) hasData=true; break;; esac
done


# Get a sensible caseName from the directory name
caseName="${PWD##*/}"
caseFile="$caseName.$extension"
fvControls="system"

if [ -n "$regionName" ]
then
    [ -d "constant/$regionName" ] || {
        echo "FATAL ERROR: Region $regionName does not exist" 1>&2
        exit 1
    }
    caseFile="$caseName{$regionName}.$extension"
    fvControls="$fvControls/$regionName"
fi

case "${optTouch:-false}" in
all)
    extension=OpenFOAM
    if [ -f system/blockMeshDict ] || [ -f constant/polyMesh/blockMeshDict ]
    then
        touch "$caseName.blockMesh"
        echo "Created '$caseName.blockMesh'" 1>&2
    fi
    touch "$caseName.$extension" "$caseName.foam"
    echo "Created '$caseName.$extension' '$caseName.foam'" 1>&2
    # Discover probable regions
    for region in constant/*
    do
        if [ -d "$region" ] && [ -d "$region/polyMesh" ]
        then
            regionName="${region##*/}"
            touch "$caseName{$regionName}.$extension"
            echo "Created '$caseName{$regionName}.$extension'" 1>&2
        fi
    done
    exit 0
    ;;
proc*)
    for i in processor*
    do
    (
        cd "$i" 2>/dev/null && touch "${caseFile%.*}#${i#processor}.$extension"
    )
    done
    echo "Created '$caseFile' for processor directories" 1>&2
    exit 0
    ;;
true)
    touch "$caseFile"
    echo "Created '$caseFile'" 1>&2
    exit 0
    ;;
esac


# Check existence of some essential OpenFOAM files.
# If caseName appears to be a processor directory, check parent as fallback
hasFiles() {
    local warn="Cannot locate OpenFOAM-format case files:"
    local parent
    case "$caseName" in (processor*) parent="../" ;; esac

    for file
    do
        if [ -s "$file" ]
        then
            continue
        elif [ -n "$parent" ] && [ -s "$parent$file" ]
        then
            continue
        else
            # Not found
            [ -n "$warn" ] && echo "$warn" 1>&2
            unset warn
            if [ -n "$parent" ]
            then
                echo "    $file, or $parent$file" 1>&2
            else
                echo "    $file" 1>&2
            fi
        fi
    done

    if [ -n "$warn" ]
    then
        return 0        # No warnings were triggered
    else
        echo 1>&2       # Emit an additional separator line
        return 1
    fi
}


if [ "${hasData:-false}" = true ]
then

    # Has --data=.., send directly to paraview
    exec paraview "$@"
    echo "Error: could not exec paraview" 1>&2
    exit 1   # This should not have happened

else

    # Check existence of essential files
    warn=false
    case "$plugin" in
    (blockReader)
        blockMeshDict=system/blockMeshDict
        if [ -f constant/polyMesh/blockMeshDict ]
        then
            blockMeshDict=constant/polyMesh/blockMeshDict
        fi

        hasFiles system/controlDict "$blockMeshDict" || warn=true
        ;;

    (foamReader)
        hasFiles \
            system/controlDict \
            "$fvControls/fvSchemes" \
            "$fvControls/fvSolution" || warn=true
        ;;
    esac

    [ "${warn:-false}" = false ] || {
        echo -n "Would you like to open paraview anyway <Y|n>: "
        read open
        case "${open:-y}" in ([Yy]*) paraview ;; esac
        exit
    }

    # Only create/remove caseFile if it did not previously exist
    [ -e "$caseFile" ] || {
        touch "$caseFile"
        echo "Created temporary '$caseFile'" 1>&2
        trap "rm -f \"$caseFile\"; exit 0" EXIT TERM INT
    }

    # For now filter out any ld.so errors. Caused by non-system compiler?
    paraview --data="$caseFile" "$@" 2>&1 \
        | grep -F -v 'Inconsistency detected'
fi


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