//===----------------------------------------------------------------------===//
//
// Part of CUDA Experimental in CUDA C++ Core Libraries,
// under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
// SPDX-FileCopyrightText: Copyright (c) 2026 NVIDIA CORPORATION.
//
//===----------------------------------------------------------------------===//

#include <cstdio>
#include <cstring>

#include <cccl/c/for.h>
#include <hostjit/codegen/cub_call.hpp>
#include <util/build_utils.h>

using namespace hostjit::codegen;

// d_in_0, num_items, op_0_state, stream
using for_fn_t = int (*)(void*, unsigned long long, void*, void*);

CUresult cccl_device_for_build_ex(
  cccl_device_for_build_result_t* build_ptr,
  cccl_iterator_t d_data,
  cccl_op_t op,
  int cc_major,
  int cc_minor,
  const char* cub_path,
  const char* thrust_path,
  const char* libcudacxx_path,
  const char* ctk_path,
  cccl_build_config* config)
try
{
  if (build_ptr == nullptr)
  {
    return CUDA_ERROR_INVALID_VALUE;
  }
  std::string cccl_include_str  = cccl::detail::parse_cccl_include_path(libcudacxx_path);
  std::string ctk_root_str      = cccl::detail::parse_ctk_root(ctk_path);
  const char* cccl_include_path = cccl_include_str.empty() ? nullptr : cccl_include_str.c_str();
  const char* ctk_root          = ctk_root_str.empty() ? nullptr : ctk_root_str.c_str();
  cccl::detail::MergedBuildConfig merged(config, cub_path, thrust_path);

  auto result =
    CubCall::from("cub/device/device_for.cuh")
      .run("cub::DeviceFor::ForEachN")
      .name("cccl_jit_for")
      .with(in(d_data), num_items, for_each_op(op), stream)
      .compile(cc_major, cc_minor, merged.get(), ctk_root, cccl_include_path);

  build_ptr->cc = cc_major * 10 + cc_minor;
  cccl::detail::copy_cubin(result.cubin, build_ptr->payload, build_ptr->payload_size);
  build_ptr->jit_compiler = result.compiler;
  build_ptr->for_fn       = result.fn_ptr;

  return CUDA_SUCCESS;
}
catch (const std::exception& exc)
{
  fprintf(stderr, "\nEXCEPTION in cccl_device_for_build_ex(): %s\n", exc.what());
  return CUDA_ERROR_UNKNOWN;
}

CUresult cccl_device_for(
  cccl_device_for_build_result_t build, cccl_iterator_t d_data, uint64_t num_items, cccl_op_t op, CUstream stream)
try
{
  if (!build.for_fn)
  {
    return CUDA_ERROR_INVALID_VALUE;
  }
  auto fn = reinterpret_cast<for_fn_t>(build.for_fn);

  const int status = fn(d_data.state, num_items, op.state, reinterpret_cast<void*>(stream));
  return (status == 0) ? CUDA_SUCCESS : CUDA_ERROR_UNKNOWN;
}
catch (const std::exception& exc)
{
  fprintf(stderr, "\nEXCEPTION in cccl_device_for(): %s\n", exc.what());
  return CUDA_ERROR_UNKNOWN;
}

CUresult cccl_device_for_build(
  cccl_device_for_build_result_t* build,
  cccl_iterator_t d_data,
  cccl_op_t op,
  int cc_major,
  int cc_minor,
  const char* cub_path,
  const char* thrust_path,
  const char* libcudacxx_path,
  const char* ctk_path)
{
  return cccl_device_for_build_ex(
    build, d_data, op, cc_major, cc_minor, cub_path, thrust_path, libcudacxx_path, ctk_path, nullptr);
}

CUresult cccl_device_for_cleanup(cccl_device_for_build_result_t* build_ptr)
try
{
  if (build_ptr == nullptr)
  {
    return CUDA_ERROR_INVALID_VALUE;
  }

  cccl::detail::release_jit_artifacts(build_ptr);
  build_ptr->for_fn = nullptr;

  return CUDA_SUCCESS;
}
catch (const std::exception& exc)
{
  fprintf(stderr, "\nEXCEPTION in cccl_device_for_cleanup(): %s\n", exc.what());
  return CUDA_ERROR_UNKNOWN;
}