# Try to find nglib/netgen
#
# Optional input NETGENDATA is path to the netgen libsrc source tree - this is
# required due to some headers not being installed by netgen.
#
# Once done this will define
#
# NGLIB_INCLUDE_DIR   - where the nglib include directory can be found
# NGLIB_LIBRARIES     - Link this to use nglib
# NETGEN_INCLUDE_DIRS - where the netgen include directories can be found
# NETGEN_DEFINITIONS  - C++ compiler defines required to use netgen/nglib
#
# See also: http://git.salome-platform.org/gitweb/?p=NETGENPLUGIN_SRC.git;a=summary


find_package(Netgen CONFIG)
IF (Netgen_FOUND)
    set(NGLIB_INCLUDE_DIR ${NETGEN_INCLUDE_DIRS})
    set(NGLIB_LIBRARIES nglib)
    set(NETGEN_DEFINITIONS -DNO_PARALLEL_THREADS -DOCCGEOMETRY)
    # for external smesh only the following two variables are needed:
    set(NETGEN_FOUND True)
    set(NETGEN_INCLUDE_DIRS ${NETGEN_INCLUDE_DIRS})

ELSE ()

    SET(NETGEN_DEFINITIONS -DNO_PARALLEL_THREADS -DOCCGEOMETRY)

    IF (WIN32)
        FIND_PATH(NGLIB_INCLUDE_DIR NAMES nglib.h PATHS ${NETGEN_INCLUDEDIR})
        SET(NETGEN_LIBS nglib mesh occ interface)
        SET(NGLIB_LIBRARIES "")
        FOREACH (it ${NETGEN_LIBS})
            FIND_LIBRARY(NGLIB ${it} PATHS ${NETGEN_LIBDIR})
            FIND_LIBRARY(NGLIBD ${it}d PATHS ${NETGEN_LIBDIR})
            IF (NGLIBD AND NGLIB)
                SET(NG_LIB optimized ${NGLIB}
                        debug ${NGLIBD})
                SET(NGLIB_LIBRARIES ${NGLIB_LIBRARIES} ${NG_LIB})
                UNSET(NGLIB CACHE)
                UNSET(NGLIBD CACHE)
            ELSEIF (NGLIB)
                SET(NGLIB_LIBRARIES ${NGLIB_LIBRARIES} ${NGLIB})
                UNSET(NGLIB CACHE)
            ENDIF ()
        ENDFOREACH ()

        IF (NOT NETGENDATA)
            SET(NETGENDATA netgen)
        ENDIF (NOT NETGENDATA)

    ELSEIF (DEFINED MACPORTS_PREFIX OR DEFINED HOMEBREW_PREFIX)
        IF (NETGEN_ROOT)
            SET(NETGEN_INCLUDEDIR ${NETGEN_ROOT}/include)
            SET(NETGEN_LIBDIR ${NETGEN_ROOT}/lib)
            # allow to customize if NETGEN_ROOT is used
            IF (NOT NETGENDATA)
                SET(NETGENDATA ${NETGEN_ROOT}/libsrc)
            ENDIF ()
        ENDIF ()

        FIND_PATH(NGLIB_INCLUDE_DIR NAMES nglib.h PATHS ${NETGEN_INCLUDEDIR} /usr/include /usr/include/netgen-mesher)
        FIND_LIBRARY(NGLIB_LIBNGLIB nglib PATHS ${NETGEN_LIBDIR} /usr/lib /usr/lib64 /usr/local/lib)
        SET(NGLIB_LIBRARIES ${NGLIB_LIBNGLIB})
        FIND_LIBRARY(NGLIB_LIBMESH NAMES mesh ngmesh PATHS ${NETGEN_LIBDIR} /usr/lib /usr/lib64 /usr/local/lib)
        IF (NGLIB_LIBMESH)
            SET(NGLIB_LIBRARIES ${NGLIB_LIBRARIES} ${NGLIB_LIBMESH})
        ENDIF ()
        FIND_LIBRARY(NGLIB_LIBOCC NAMES occ ngocc PATHS ${NETGEN_LIBDIR} /usr/lib /usr/lib64 /usr/local/lib)
        IF (NGLIB_LIBOCC)
            SET(NGLIB_LIBRARIES ${NGLIB_LIBRARIES} ${NGLIB_LIBOCC})
        ENDIF ()
        FIND_LIBRARY(NGLIB_LIBINTERFACE NAMES interface nginterface PATHS ${NETGEN_LIBDIR} /usr/lib /usr/lib64 /usr/local/lib)
        IF (NGLIB_LIBINTERFACE)
            SET(NGLIB_LIBRARIES ${NGLIB_LIBRARIES} ${NGLIB_LIBINTERFACE})
        ENDIF ()

        IF (NOT NETGENDATA)
            SET(NETGENDATA /usr/share/netgen/libsrc)
        ENDIF ()
    ENDIF ()

    FIND_PATH(NETGEN_DIR_include NAMES mydefs.hpp NO_DEFAULT_PATH PATHS ${NGLIB_INCLUDE_DIR}/include ${NETGENDATA}/include ${NETGEN_INCLUDEDIR} ${NGLIB_INCLUDE_DIR})

    IF (NOT NGLIB_INCLUDE_DIR AND NOT NETGEN_DIR_include)
        MESSAGE(STATUS "Cannot find NETGEN header files.")
    ELSEIF (NOT NETGEN_VERSION)
        file(STRINGS ${NETGEN_DIR_include}/mydefs.hpp NETGEN_VERSION REGEX "#define PACKAGE_VERSION.*")
    ENDIF ()

    IF (NOT NGLIB_LIBRARIES)
        MESSAGE(STATUS "Cannot find NETGEN library.")
    ENDIF ()

    IF (NGLIB_INCLUDE_DIR AND NGLIB_LIBRARIES)
        SET(Netgen_FOUND TRUE)
        SET(NETGEN_INCLUDE_DIRS ${NETGEN_DIR_include} ${NGLIB_INCLUDE_DIR})
        LIST(REMOVE_DUPLICATES NETGEN_INCLUDE_DIRS)
    ELSE ()
        SET(Netgen_FOUND FALSE)
    ENDIF ()
ENDIF ()

# Package-provided cMake file is not enough
IF (Netgen_FOUND)
    IF (NOT NETGEN_VERSION_MAJOR)
        IF (NETGEN_VERSION)
            string(REGEX MATCHALL "[0-9]+" NETGEN_VERSION_expr ${NETGEN_VERSION})
            list(LENGTH NETGEN_VERSION_expr NETGEN_VERSION_COUNT)
            list(GET NETGEN_VERSION_expr 0 NETGEN_VERSION_MAJOR)
            IF (NETGEN_VERSION_COUNT GREATER 1)
                list(GET NETGEN_VERSION_expr 1 NETGEN_VERSION_MINOR)
            ELSE ()
                set(NETGEN_VERSION_MINOR 0)
            ENDIF ()
        ELSE ()  # workaround for netgen 6.2 and newer. currently there is no easy way to detect the version
            # better use "find_package(netgen CONFIG REQUIRED)"
            set(NETGEN_VERSION_MAJOR 6)
            set(NETGEN_VERSION_MINOR 2)
        ENDIF ()
        set(NETGEN_VERSION_PATCH 0)
    ENDIF ()

    MATH(EXPR NETGEN_VERSION_C "(${NETGEN_VERSION_MAJOR} << 16) + (${NETGEN_VERSION_MINOR} << 8) + (${NETGEN_VERSION_PATCH})")
    MATH(EXPR NETGEN_VERSION_62 "(6 << 16) + (2 << 8)")
    MATH(EXPR NETGEN_VERSION_62_2004 "(6 << 16) + (2 << 8) + (2004)")
    IF (NOT NETGEN_VERSION_C LESS NETGEN_VERSION_62) # Version >= 6.2
        IF (CMAKE_CXX_COMPILER_ID MATCHES "Clang")
            # Clang sometimes fails to include <cstdio>
            include(CMakePushCheckState)
            cmake_push_check_state(RESET)
            set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} ${NETGEN_CXX_FLAGS}")
            check_cxx_source_compiles("#include <cstdio>\nint main(){}" CSTDIO_INCLUDE_TRY1)
            IF (NOT CSTDIO_INCLUDE_TRY1)
                # Ugly hack to make <stdio.h> building gets function
                set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -U__cplusplus -D__cplusplus=201103L")
                check_cxx_source_compiles("#include <cstdio>\nint main(){}" CSTDIO_INCLUDE_TRY2)
                IF (NOT CSTDIO_INCLUDE_TRY2)
                    message(FATAL_ERROR "Cannot #include <cstdio>.")
                ELSE ()
                    set(NETGEN_CXX_FLAGS "${NETGEN_CXX_FLAGS} -U__cplusplus -D__cplusplus=201103L")
                ENDIF ()
            ENDIF ()
            cmake_pop_check_state()
        ENDIF ()
    ENDIF ()
    MESSAGE(STATUS "Found NETGEN version ${NETGEN_VERSION_MAJOR}.${NETGEN_VERSION_MINOR}, calculated: ${NETGEN_VERSION_C}")
    LIST(APPEND NETGEN_DEFINITIONS -DNETGEN_VERSION=${NETGEN_VERSION_C})
ENDIF ()