if(OGS_BUILD_WHEEL)
    return()
endif()

# CMake function to handle pybind11 version-compatible linker flags
# This prevents the linker from stripping the module initialization function
function(dont_strip_pybind11_init_function target_name module_name)
    # Only apply when building static libraries to prevent symbol stripping
    if(BUILD_SHARED_LIBS)
        return()
    endif()

    set(pybind11_init_function "")

    # Detect pybind11 version
    if(DEFINED pybind11_VERSION)
        if(pybind11_VERSION VERSION_GREATER_EQUAL "3.0")
            set(pybind11_init_function "pybind11_init_${module_name}")
        else()
            set(pybind11_init_function "pybind11_init_impl_${module_name}")
        endif()
    elseif(DEFINED PYBIND11_VERSION_MAJOR)
        if(PYBIND11_VERSION_MAJOR GREATER_EQUAL 3)
            set(pybind11_init_function "pybind11_init_${module_name}")
        else()
            set(pybind11_init_function "pybind11_init_impl_${module_name}")
        endif()
    endif()

    message(STATUS "Using pybind11 init function: ${pybind11_init_function}")

    # Linker flags to prevent symbol stripping
    if(COMPILER_IS_GCC OR COMPILER_IS_CLANG)
        if(APPLE)
            target_link_options(${target_name} PRIVATE
                "LINKER:-u,_${pybind11_init_function}")
        else()
            target_link_options(${target_name} PRIVATE
                "LINKER:--undefined=${pybind11_init_function}")
        endif()
    elseif(COMPILER_IS_MSVC)
        target_link_options(${target_name} PRIVATE
            "/INCLUDE:${pybind11_init_function}")
    else()
        # Fallback for unsupported compilers
        message(WARNING "Unsupported compiler, manual linker configuration may be needed")
    endif()

    message(STATUS "Applied linker flags to prevent stripping of ${pybind11_init_function}")
endfunction()

# Troubleshooting: If you get linker errors, such as   ogs.cpp:(.text+0xb4):
# undefined reference to `_Py_ZeroStruct' it could be that OGS is compiled with
# the wrong Python version. I (Ch. Leh.) observed the following: The symbol
# _Py_ZeroStruct could not be found in /usr/lib/libpython3.6m.so (I intended to
# compile OGS with Python3). It's apparently a Python2 symbol (present in
# /usr/lib/libpython2.7.so) The compiler command-line was the following:
# ~~~
# /usr/bin/g++ ... -DvtkRenderingVolume_AUTOINIT="1(vtkRenderingVolumeOpenGL2)" \
#     -I/usr/include/vtk -I/usr/include/python2.7 -I/usr/include/freetype2 \
#     -I/usr/include/libxml2 ... -I/.../BaseLib ... \
#     -isystem /usr/include/python3.6m ... -o CMakeFiles/ogs.dir/ogs.cpp.o \
#     -c /.../Applications/CLI/ogs.cpp
# ~~~
# In particular, the Python2 include path comes before the Python3 include path.
# Compiling OGS with Python2 solved the issue. I assume (this is only a guess!)
# that VTK pulls in Python2 dependencies (on my system). I assume that this is
# related to https://github.com/ufz/ogs/pull/2158. Workaround: Always make sure
# that OGS is compiled with the same Python version as VTK. The error described
# above should be detected automatically by cmake and an appropriate message
# should be presented. The note is kept for the case that the automatic
# detection does not work due to whatever reason.

# TODO: Make this work in python interpreters,
# see https://github.com/pybind/pybind11/discussions/5079
ogs_add_library(ogs_embedded_python ogs_embedded_python.cpp)

# Performance warning from
# https://github.com/pybind/pybind11/blob/master/docs/compiling.rst: Since
# pybind11 is a metatemplate library, it is crucial that certain compiler flags
# are provided to ensure high quality code generation. In contrast to the
# pybind11_add_module() command, the CMake interface library only provides the
# minimal set of parameters to ensure that the code using pybind11 compiles, but
# it does not pass these extra compiler flags (i.e. this is up to you). TODO:
# Enable further compiler/linker flags.
target_link_libraries(
    ogs_embedded_python PUBLIC pybind11::embed
    PRIVATE ProcessLibBoundaryConditionAndSourceTermPythonModule
)
target_compile_definitions(
    ogs_embedded_python
    PUBLIC OGS_EMBED_PYTHON_INTERPRETER
)

dont_strip_pybind11_init_function(ogs_embedded_python "OpenGeoSys")

ogs_add_executable(ogs ogs.cpp CommandLineArgumentParser.cpp)

target_link_libraries(
    ogs
    PRIVATE
        ApplicationsLib
        BaseLib
        CMakeInfoLib
        GitInfoLib
        MeshLib
        ProcessLib
        $<$<AND:$<BOOL:${OGS_USE_PETSC}>,$<TARGET_EXISTS:MPI::MPI_CXX>>:MPI::MPI_CXX>
        $<$<TARGET_EXISTS:InSituLib>:InSituLib>
        $<$<TARGET_EXISTS:petsc>:petsc>
        tclap
)

# ---- Tests ----
add_test(NAME ogs_no_args COMMAND ogs)
set_tests_properties(ogs_no_args PROPERTIES WILL_FAIL TRUE LABELS "default")

# ---- Installation ----
install(TARGETS ogs RUNTIME DESTINATION bin)

set(CPACK_PACKAGE_EXECUTABLES ${CPACK_PACKAGE_EXECUTABLES} "ogs"
                              "OGS Simulator"
)
cpack_add_component(
    ogs_cli
    DISPLAY_NAME "OGS THMC Simulator"
    DESCRIPTION "The command line interface for OpenGeoSys."
    GROUP Applications
)