# Generate py-interface and package targets

# CLANG installed must be 14.0 or above
set(clang_ver 14.0)
set(ctypeslib_ver 2.3.2)

set(PY_BUILD_DIR "python_package")
# amdsmi part of this string is the directory containing all python files
# additionally defined in pyproject.toml
set(PY_PACKAGE_DIR "${PY_BUILD_DIR}/amdsmi")
set(PY_WRAPPER_INSTALL_DIR "${SHARE_INSTALL_PREFIX}" CACHE STRING "Wrapper installation directory")

# TODO: Figure out how python-clang and clang are related

# try to find clang of the right version
set(GOOD_CLANG_FOUND FALSE)
# only try to re-generate amdsmi_wrapper.py if BUILD_WRAPPER is on/true
if(BUILD_WRAPPER)
    find_program(clang NAMES clang REQUIRED)
    # extract clang version manually because find_package(clang) doesn't work
    execute_process(COMMAND ${clang} --version OUTPUT_VARIABLE clang_full_version_string)
    string (REGEX REPLACE ".*clang version ([0-9]+\\.[0-9]+).*" "\\1" CLANG_VERSION_STRING ${clang_full_version_string})
    if((CLANG_VERSION_STRING VERSION_GREATER clang_ver) OR (CLANG_VERSION_STRING VERSION_EQUAL clang_ver))
        message("GOOD CLANG VERSION: ${CLANG_VERSION_STRING}")
        set(GOOD_CLANG_FOUND TRUE)
    else()
        message(FATAL_ERROR "${clang} VERSION TOO OLD!: ${CLANG_VERSION_STRING}")
    endif()
endif()

if(NOT GOOD_CLANG_FOUND)
    # keep old wrapper because no clang found
    message(AUTHOR_WARNING "A wrapper will not be re-generated! Using old wrapper instead.\nSet -DBUILD_WRAPPER=ON to re-build the wrapper")
    add_custom_command(
        OUTPUT amdsmi_wrapper.py
               ${PY_PACKAGE_DIR}/amdsmi_wrapper.py
        DEPENDS ${AMD_SMI}
                ${CMAKE_CURRENT_SOURCE_DIR}/amdsmi_wrapper.py
        COMMAND cp -f ${CMAKE_CURRENT_SOURCE_DIR}/amdsmi_wrapper.py ${CMAKE_CURRENT_BINARY_DIR}/
        # hacky alternative to configure_file that will run at MAKE compile instead of CMake configure
        COMMAND sed -i
                s:"@CPACK_PACKAGING_INSTALL_PREFIX@/@CMAKE_INSTALL_LIBDIR@":"${CPACK_PACKAGING_INSTALL_PREFIX}/${CMAKE_INSTALL_LIBDIR}":g
                ${CMAKE_CURRENT_BINARY_DIR}/amdsmi_wrapper.py
        COMMAND mkdir -p ${PY_PACKAGE_DIR}
        COMMAND ln -Pf ${CMAKE_CURRENT_BINARY_DIR}/amdsmi_wrapper.py ${PY_PACKAGE_DIR}/)
else()
    find_package(Python3 3.7 COMPONENTS Interpreter Development REQUIRED)
    # --break-system-packages is needed for python 3.11
    # see: https://peps.python.org/pep-0668/
    add_custom_target(
        python_pre_reqs
        COMMAND ${Python3_EXECUTABLE} -m pip install --break-system-packages clang==${clang_ver} ctypeslib2==${ctypeslib_ver})
    # generate new wrapper
    configure_file(${PROJECT_SOURCE_DIR}/tools/generator.py generator.py @ONLY COPYONLY)
    add_custom_command(
        OUTPUT amdsmi.h
               ${CMAKE_CURRENT_SOURCE_DIR}/amdsmi_wrapper.py
               amdsmi_wrapper.py
               ${PY_PACKAGE_DIR}/amdsmi_wrapper.py
        DEPENDS ${AMD_SMI}
                python_pre_reqs
                generator.py
                ${PROJECT_SOURCE_DIR}/include/amd_smi/amdsmi.h
        COMMAND cp ${PROJECT_SOURCE_DIR}/include/amd_smi/amdsmi.h ./
        COMMAND ${Python3_EXECUTABLE} generator.py -i amdsmi.h -l ${PROJECT_BINARY_DIR}/src/libamd_smi.so -o ${CMAKE_CURRENT_SOURCE_DIR}/amdsmi_wrapper.py
        COMMAND cp -f ${CMAKE_CURRENT_SOURCE_DIR}/amdsmi_wrapper.py ${CMAKE_CURRENT_BINARY_DIR}/
        # hacky alternative to configure_file that will run at MAKE compile instead of CMake configure
        COMMAND sed -i
                s:"@CPACK_PACKAGING_INSTALL_PREFIX@/@CMAKE_INSTALL_LIBDIR@":"${CPACK_PACKAGING_INSTALL_PREFIX}/${CMAKE_INSTALL_LIBDIR}":g
                ${CMAKE_CURRENT_BINARY_DIR}/amdsmi_wrapper.py
        COMMAND mkdir -p ${PY_PACKAGE_DIR}
        COMMAND ln -Pf ${CMAKE_CURRENT_BINARY_DIR}/amdsmi_wrapper.py ${PY_PACKAGE_DIR}/)
endif()

add_custom_target(
    python_wrapper
    DEPENDS amdsmi_wrapper.py)

# hard-linking instead of copying avoids unnecessarry regeneration of packaged files
add_custom_command(
    OUTPUT ${PY_BUILD_DIR}/pyproject.toml
           ${PY_PACKAGE_DIR}/__init__.py
           ${PY_PACKAGE_DIR}/amdsmi_exception.py
           ${PY_PACKAGE_DIR}/amdsmi_interface.py
           ${PY_PACKAGE_DIR}/README.md
           ${PY_PACKAGE_DIR}/LICENSE
    DEPENDS python_wrapper
    COMMAND ln -Pf ${CMAKE_CURRENT_SOURCE_DIR}/pyproject.toml ${PY_BUILD_DIR}/
    COMMAND ln -Pf ${CMAKE_CURRENT_SOURCE_DIR}/__init__.py ${PY_PACKAGE_DIR}/
    COMMAND ln -Pf ${CMAKE_CURRENT_SOURCE_DIR}/amdsmi_exception.py ${PY_PACKAGE_DIR}/
    COMMAND ln -Pf ${CMAKE_CURRENT_SOURCE_DIR}/amdsmi_interface.py ${PY_PACKAGE_DIR}/
    COMMAND ln -Pf ${CMAKE_CURRENT_SOURCE_DIR}/README.md ${PY_PACKAGE_DIR}/
    COMMAND ln -Pf ${PROJECT_SOURCE_DIR}/LICENSE ${PY_PACKAGE_DIR}/)

add_custom_target(
    python_package ALL
    DEPENDS ${PY_BUILD_DIR}/pyproject.toml
            ${PY_PACKAGE_DIR}/__init__.py
            ${PY_PACKAGE_DIR}/amdsmi_exception.py
            ${PY_PACKAGE_DIR}/amdsmi_interface.py
            ${PY_PACKAGE_DIR}/README.md
            ${PY_PACKAGE_DIR}/LICENSE)

install(
    FILES ${CMAKE_CURRENT_BINARY_DIR}/${PY_BUILD_DIR}/pyproject.toml
    DESTINATION ${PY_WRAPPER_INSTALL_DIR}
    COMPONENT dev)

install(
    DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/${PY_PACKAGE_DIR}
    DESTINATION ${PY_WRAPPER_INSTALL_DIR}
    COMPONENT dev)