#----------------------------------*-sh-*--------------------------------------
# =========                 |
# \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
#  \\    /   O peration     |
#   \\  /    A nd           | Copyright (C) 2017 OpenCFD Ltd.
#    \\/     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
#     cmakeFunctions
#
# Description
#     Helper functions for CMake
#------------------------------------------------------------------------------

# Source the wmake functions
. $WM_PROJECT_DIR/wmake/scripts/wmakeFunctions

# Ensure CMake gets the correct C/C++ compilers
[ -n "$WM_CC" ]  && export CC="$WM_CC"
[ -n "$WM_CXX" ] && export CXX="$WM_CXX"


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

#
# Check sentinel file(s) to handle paraview / vtk version changes
#
sameDependency()
{
    local depend="$1"
    findObjectDir "$2"  # Where generated files are stored
    local sentinel="$objectsDir/ThirdParty"

    echo $sentinel

    local prev
    if read -r prev 2>/dev/null < $sentinel
    then
        if [ "$prev" = "$depend" ]
        then
            return 0
        else
            echo "${depend%=*} changed between builds" 1>&2
            return 1
        fi
    elif [ -f "$objectsDir/CMakeCache.txt" ]
    then
        echo "previous build was incomplete" 1>&2
        return 1
    else
        return 0
    fi
}


# CMake into objectsDir with external dependency
cmakeVersioned()
{
    local depend="$1"
    local sourceDir="$2"
    findObjectDir $sourceDir # Where are generated files stored?

    local sentinel

    # version changed
    sentinel=$(sameDependency "$depend" "$sourceDir") \
        || rm -rf "$objectsDir" > /dev/null 2>&1

    test -f "$objectsDir/CMakeCache.txt"
    retry=$? # Additional attempt if sources moved

    mkdir -p $objectsDir && \
    (
        cd $objectsDir || exit 1

        cmake $sourceDir || {
            if [ $retry -eq 0 ]
            then
                echo "Removing CMakeCache.txt and attempt again" 1>&2
                rm -f CMakeCache.txt
                cmake $sourceDir
            else
                exit 1
            fi
        } && make && { echo "$depend" > $sentinel; }
    )
}


# CMake into objectsDir with VTK_DIR dependency
cmakeVtk()
{
    cmakeVersioned "VTK_DIR=$VTK_DIR" "$1"
}


# CMake into objectsDir with ParaView_DIR dependency
cmakePv()
{
    cmakeVersioned "ParaView_DIR=$ParaView_DIR" "$1"
}


#
# Build library - use sentinel file(s) to handle paraview version changes
#
wmakeLibPv()
{
    local depend="ParaView_DIR=$ParaView_DIR"
    local sentinel

    for libName
    do
        # version changed
        sentinel=$(sameDependency "$depend" $libName) || wclean $libName
        wmake $targetType $libName && { echo "$depend" > $sentinel; }
    done
}


#
# There are several prerequisites for building plugins
#
canBuildPlugin()
{
    [ -d "$ParaView_DIR" -a -r "$ParaView_DIR" ] || {
        echo "==> cannot build ParaView plugins without paraview directory"
        echo "    ParaView_DIR=$ParaView_DIR"
        return 1
    }

    [ -n "$PV_PLUGIN_PATH" ] || {
        echo "==> ${PWD##*/} : invalid PV_PLUGIN_PATH for building ParaView plugins"
        echo "    PV_PLUGIN_PATH=${PV_PLUGIN_PATH:-unset}"
        return 1
    }

    type cmake > /dev/null 2>&1 || {
        echo "==> cannot build ParaView plugins without cmake"
        return 1
    }

    return 0 # success
}


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