# Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
# file Copyright.txt or https://cmake.org/licensing for details.

function(protobuf_generate)
    set(_options APPEND_PATH DESCRIPTORS)
    set(_singleargs LANGUAGE OUT_VAR EXPORT_MACRO PROTOC_OUT_DIR)
    if (COMMAND target_sources)
        list(APPEND _singleargs TARGET)
    endif ()
    set(_multiargs PROTOS IMPORT_DIRS GENERATE_EXTENSIONS)

    cmake_parse_arguments(protobuf_generate "${_options}" "${_singleargs}" "${_multiargs}" "${ARGN}")

    if (NOT protobuf_generate_PROTOS AND NOT protobuf_generate_TARGET)
        message(SEND_ERROR "Error: protobuf_generate called without any targets or source files")
        return()
    endif ()

    if (NOT protobuf_generate_OUT_VAR AND NOT protobuf_generate_TARGET)
        message(SEND_ERROR "Error: protobuf_generate called without a target or output variable")
        return()
    endif ()

    if (NOT protobuf_generate_LANGUAGE)
        set(protobuf_generate_LANGUAGE cpp)
    endif ()
    string(TOLOWER ${protobuf_generate_LANGUAGE} protobuf_generate_LANGUAGE)

    if (NOT protobuf_generate_PROTOC_OUT_DIR)
        set(protobuf_generate_PROTOC_OUT_DIR ${CMAKE_CURRENT_BINARY_DIR})
    endif ()

    if (protobuf_generate_EXPORT_MACRO AND protobuf_generate_LANGUAGE STREQUAL cpp)
        set(_dll_export_decl "dllexport_decl=${protobuf_generate_EXPORT_MACRO}:")
    endif ()

    if (NOT protobuf_generate_GENERATE_EXTENSIONS)
        if (protobuf_generate_LANGUAGE STREQUAL cpp)
            set(protobuf_generate_GENERATE_EXTENSIONS .pb.h .pb.cc)
        elseif (protobuf_generate_LANGUAGE STREQUAL python)
            set(protobuf_generate_GENERATE_EXTENSIONS _pb2.py)
        else ()
            message(SEND_ERROR "Error: protobuf_generate given unknown Language ${LANGUAGE}, please provide a value for GENERATE_EXTENSIONS")
            return()
        endif ()
    endif ()

    if (protobuf_generate_TARGET)
        get_target_property(_source_list ${protobuf_generate_TARGET} SOURCES)
        foreach (_file ${_source_list})
            if (_file MATCHES "proto$")
                list(APPEND protobuf_generate_PROTOS ${_file})
            endif ()
        endforeach ()
    endif ()

    if (NOT protobuf_generate_PROTOS)
        message(SEND_ERROR "Error: protobuf_generate could not find any .proto files")
        return()
    endif ()

    if (protobuf_generate_APPEND_PATH)
        # Create an include path for each file specified
        foreach (_file ${protobuf_generate_PROTOS})
            get_filename_component(_abs_file ${_file} ABSOLUTE)
            get_filename_component(_abs_path ${_abs_file} PATH)
            list(FIND _protobuf_include_path ${_abs_path} _contains_already)
            if (${_contains_already} EQUAL -1)
                list(APPEND _protobuf_include_path -I ${_abs_path})
            endif ()
        endforeach ()
    else ()
        set(_protobuf_include_path -I ${CMAKE_CURRENT_SOURCE_DIR})
    endif ()

    foreach (DIR ${protobuf_generate_IMPORT_DIRS})
        get_filename_component(ABS_PATH ${DIR} ABSOLUTE)
        list(FIND _protobuf_include_path ${ABS_PATH} _contains_already)
        if (${_contains_already} EQUAL -1)
            list(APPEND _protobuf_include_path -I ${ABS_PATH})
        endif ()
    endforeach ()

    set(_generated_srcs_all)
    foreach (_proto ${protobuf_generate_PROTOS})
        get_filename_component(_abs_file ${_proto} ABSOLUTE)
        get_filename_component(_abs_dir ${_abs_file} DIRECTORY)
        get_filename_component(_basename ${_proto} NAME_WE)
        file(RELATIVE_PATH _rel_dir ${CMAKE_CURRENT_SOURCE_DIR} ${_abs_dir})

        set(_generated_srcs)
        foreach (_ext ${protobuf_generate_GENERATE_EXTENSIONS})
            list(APPEND _generated_srcs "${protobuf_generate_PROTOC_OUT_DIR}/${_basename}${_ext}")
        endforeach ()

        if (protobuf_generate_DESCRIPTORS AND protobuf_generate_LANGUAGE STREQUAL cpp)
            set(_descriptor_file "${CMAKE_CURRENT_BINARY_DIR}/${_basename}.desc")
            set(_dll_desc_out "--descriptor_set_out=${_descriptor_file}")
            list(APPEND _generated_srcs ${_descriptor_file})
        endif ()
        list(APPEND _generated_srcs_all ${_generated_srcs})

        add_custom_command(
                OUTPUT ${_generated_srcs}
                COMMAND protobuf::protoc
                ARGS --${protobuf_generate_LANGUAGE}_out ${_dll_export_decl}${protobuf_generate_PROTOC_OUT_DIR} ${_dll_desc_out} ${_protobuf_include_path} ${_abs_file}
                DEPENDS ${_abs_file} protobuf::protoc
                COMMENT "Running ${protobuf_generate_LANGUAGE} protocol buffer compiler on ${_proto}"
                VERBATIM)
    endforeach ()

    set_source_files_properties(${_generated_srcs_all} PROPERTIES GENERATED TRUE)
    if (protobuf_generate_OUT_VAR)
        set(${protobuf_generate_OUT_VAR} ${_generated_srcs_all} PARENT_SCOPE)
    endif ()
    if (protobuf_generate_TARGET)
        target_sources(${protobuf_generate_TARGET} PRIVATE ${_generated_srcs_all})
    endif ()
endfunction()

function(PROTOBUF_GENERATE_CPP SRCS HDRS)
    cmake_parse_arguments(protobuf_generate_cpp "" "EXPORT_MACRO;DESCRIPTORS" "" ${ARGN})

    set(_proto_files "${protobuf_generate_cpp_UNPARSED_ARGUMENTS}")
    if (NOT _proto_files)
        message(SEND_ERROR "Error: PROTOBUF_GENERATE_CPP() called without any proto files")
        return()
    endif ()

    if (PROTOBUF_GENERATE_CPP_APPEND_PATH)
        set(_append_arg APPEND_PATH)
    endif ()

    if (protobuf_generate_cpp_DESCRIPTORS)
        set(_descriptors DESCRIPTORS)
    endif ()

    if (DEFINED PROTOBUF_IMPORT_DIRS AND NOT DEFINED Protobuf_IMPORT_DIRS)
        set(Protobuf_IMPORT_DIRS "${PROTOBUF_IMPORT_DIRS}")
    endif ()

    if (DEFINED Protobuf_IMPORT_DIRS)
        set(_import_arg IMPORT_DIRS ${Protobuf_IMPORT_DIRS})
    endif ()

    set(_outvar)
    protobuf_generate(${_append_arg} ${_descriptors} LANGUAGE cpp EXPORT_MACRO ${protobuf_generate_cpp_EXPORT_MACRO} OUT_VAR _outvar ${_import_arg} PROTOS ${_proto_files})

    set(${SRCS})
    set(${HDRS})
    if (protobuf_generate_cpp_DESCRIPTORS)
        set(${protobuf_generate_cpp_DESCRIPTORS})
    endif ()

    foreach (_file ${_outvar})
        if (_file MATCHES "cc$")
            list(APPEND ${SRCS} ${_file})
        elseif (_file MATCHES "desc$")
            list(APPEND ${protobuf_generate_cpp_DESCRIPTORS} ${_file})
        else ()
            list(APPEND ${HDRS} ${_file})
        endif ()
    endforeach ()
    set(${SRCS} ${${SRCS}} PARENT_SCOPE)
    set(${HDRS} ${${HDRS}} PARENT_SCOPE)
    if (protobuf_generate_cpp_DESCRIPTORS)
        set(${protobuf_generate_cpp_DESCRIPTORS} "${${protobuf_generate_cpp_DESCRIPTORS}}" PARENT_SCOPE)
    endif ()
endfunction()

function(PROTOBUF_GENERATE_PYTHON SRCS)
    if (NOT ARGN)
        message(SEND_ERROR "Error: PROTOBUF_GENERATE_PYTHON() called without any proto files")
        return()
    endif ()

    if (PROTOBUF_GENERATE_CPP_APPEND_PATH)
        set(_append_arg APPEND_PATH)
    endif ()

    if (DEFINED PROTOBUF_IMPORT_DIRS AND NOT DEFINED Protobuf_IMPORT_DIRS)
        set(Protobuf_IMPORT_DIRS "${PROTOBUF_IMPORT_DIRS}")
    endif ()

    if (DEFINED Protobuf_IMPORT_DIRS)
        set(_import_arg IMPORT_DIRS ${Protobuf_IMPORT_DIRS})
    endif ()

    set(_outvar)
    protobuf_generate(${_append_arg} LANGUAGE python OUT_VAR _outvar ${_import_arg} PROTOS ${ARGN})
    set(${SRCS} ${_outvar} PARENT_SCOPE)
endfunction()


function(PROTOBUF_SET_GENERATED target)
    # See CMake Issue : https://gitlab.kitware.com/cmake/cmake/-/issues/18399
    get_target_property(GENERATED_PROTO_FILES ${target} GENERATED_FILES)
    foreach (PROTO_FILE IN LISTS GENERATED_PROTO_FILES)
        set_source_files_properties(${PROTO_FILE} PROPERTIES GENERATED TRUE)
    endforeach ()
endfunction()