#----------------------------------*-sh-*--------------------------------------
# =========                 |
# \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
#  \\    /   O peration     |
#   \\  /    A nd           | Copyright (C) 2018-2019 OpenCFD Ltd.
#    \\/     M anipulation  |
#------------------------------------------------------------------------------
# License
#     This file is part of OpenFOAM, licensed under GNU General Public License
#     <http://www.gnu.org/licenses/>.
#
# Script
#     have_scotch
#
# Description
#     Detection/setup of scotch
#
# Requires
#     config.sh/scotch
#
# Functions provided
#     have_scotch, no_scotch, echo_scotch
#
# Variables set on success
#     HAVE_SCOTCH
#     SCOTCH_ARCH_PATH
#     SCOTCH_INC_DIR
#     SCOTCH_LIB_DIR
#
#------------------------------------------------------------------------------
. $WM_PROJECT_DIR/wmake/scripts/sysFunctions # General system functions

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

# Reset variables
no_scotch()
{
    unset HAVE_SCOTCH SCOTCH_ARCH_PATH SCOTCH_INC_DIR SCOTCH_LIB_DIR
    unset SCOTCH_VERSION
    return 0
}


# Report
echo_scotch()
{
    echo "scotch=${HAVE_SCOTCH:-false}"
    echo "root=$SCOTCH_ARCH_PATH"
    echo "include=$SCOTCH_INC_DIR"
    echo "library=$SCOTCH_LIB_DIR"
}


# On success, return 0 and export variables
# -> HAVE_SCOTCH, SCOTCH_ARCH_PATH, SCOTCH_INC_DIR, SCOTCH_LIB_DIR
have_scotch()
{
    local prefix header library static settings warn
    warn="==> skip scotch"

    # Setup
    if settings=$($WM_PROJECT_DIR/bin/foamEtcFile config.sh/scotch)
    then
        . "$settings"
    else
        [ -n "$warn" ] && echo "$warn (no config.sh/scotch settings)"
        return 2
    fi

    # Location
    prefix="$SCOTCH_ARCH_PATH"

    # Header/library names
    header="scotch.h"
    library="libscotch$extLibso"
    static="libscotch$extLiba"

    # ----------------------------------
    if isNone "$prefix"
    then
        [ -n "$warn" ] && echo "$warn (disabled)"
        return 1
    elif hasAbsdir "$prefix"
    then
        header=$(findFirstFile "$prefix/include/$header")

        library=$(findFirstFile \
            "$(thirdExtLib $library)" \
            "$prefix/lib/$static" \
            "$prefix/lib/$library" \
            "$prefix/lib$WM_COMPILER_LIB_ARCH/$static" \
            "$prefix/lib$WM_COMPILER_LIB_ARCH/$library" \
        )

    elif isSystem "$prefix"
    then
        prefix=/usr

        header=$(findFirstFile \
            "/usr/local/include/scotch/$header" \
            "/usr/local/include/$header" \
            "/usr/include/scotch/$header" \
            "/usr/include/$header" \
        )

        case "$header" in (/usr/local/*) prefix=/usr/local ;; esac

        library=$(findFirstFile \
            "$prefix/lib/$library" \
            "$prefix/lib$WM_COMPILER_LIB_ARCH/$library" \
        )
    else
        unset prefix header library
    fi
    # ----------------------------------

    # Header found?
    [ -n "$header" ] || {
        [ -n "$warn" ] && echo "$warn (no header)"
        return 2
    }

    # Library found?
    [ -n "$library" ] || {
        [ -n "$warn" ] && echo "$warn (no library)"
        return 2
    }

    local good label

    # Ensure consistent sizes between OpenFOAM and scotch header
    # extract 'typedef int64_t SCOTCH_Num' or equivalent
    label=$(sed -ne \
        's/^.*typedef *\([^ ]*\) *SCOTCH_Num.*/\1/p' \
        "$header")
    : "${label:=unknown}"


    # No SCOTCH_VERSION set? Try to obtain from header
    # extract #define SCOTCH_VERSION, SCOTCH_RELEASE, SCOTCH_PATCHLEVEL
    [ -n "$SCOTCH_VERSION" ] || \
    SCOTCH_VERSION=$(
        eval $(
            sed -ne \
            's/^ *#define *SCOTCH_\(VERSION\|RELEASE\|PATCHLEVEL\) *\([0-9][0-9]*\).*$/\1=\2/p' \
            "$header"
        )

        set -- $VERSION $RELEASE $PATCHLEVEL
        IFS="."
        [ "$#" -gt 0 ] && echo "scotch-$*"
    )
    : "${SCOTCH_VERSION:=scotch}"  # Failsafe value

    case "$WM_LABEL_SIZE:$label" in
    (32:int32_t | 32:int | 64:int64_t | 64:long)
        good=true
        ;;

    (*)
        if [ -n "$warn" ]
        then
            echo "$warn (label='$WM_LABEL_SIZE', ${header##*/} has '$label')"
        fi
        no_scotch
        return 1
        ;;
    esac

    # OK
    echo "scotch (label=$label) - $prefix"
    export HAVE_SCOTCH=true
    export SCOTCH_ARCH_PATH="$prefix"
    export SCOTCH_INC_DIR="${header%/*}"     # Basename
    export SCOTCH_LIB_DIR="${library%/*}"    # Basename
    export SCOTCH_VERSION
}


# Force reset of old variables
no_scotch

# Testing
if [ "$1" = "-test" ]
then
    have_scotch
    echo_scotch
fi

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