// Copyright 2009-2021 Intel Corporation
// SPDX-License-Identifier: Apache-2.0

/* detect Linux platform */
#if defined(linux) || defined(__linux__) || defined(__LINUX__)
#  if !defined(__LINUX__)
#     define __LINUX__
#  endif
#endif

#if defined(__LINUX__)
#include <dlfcn.h>
#else
#include <windows.h>
#endif

#include "ze_wrapper.h"

#include "../rtbuild/rtbuild.h"

#include <iostream>
#include <cstdio>
#include <cassert>
#include <mutex>
#include <string.h>

ZeWrapper::RTAS_BUILD_MODE ZeWrapper::rtas_builder = ZeWrapper::AUTO;

static std::mutex zeWrapperMutex;
static void* handle = nullptr;

static decltype(zeMemFree)* zeMemFreeInternal = nullptr;
static decltype(zeMemAllocShared)* zeMemAllocSharedInternal = nullptr;
static decltype(zeDriverGetExtensionProperties)* zeDriverGetExtensionPropertiesInternal = nullptr;
static decltype(zeDeviceGetProperties)* zeDeviceGetPropertiesInternal = nullptr;
static decltype(zeDeviceGetModuleProperties)* zeDeviceGetModulePropertiesInternal = nullptr;

static decltype(zeRTASBuilderCreateExp)* zeRTASBuilderCreateExpInternal = nullptr;
static decltype(zeRTASBuilderDestroyExp)* zeRTASBuilderDestroyExpInternal = nullptr;
static decltype(zeDriverRTASFormatCompatibilityCheckExp)* zeDriverRTASFormatCompatibilityCheckExpInternal = nullptr;
static decltype(zeRTASBuilderGetBuildPropertiesExp)* zeRTASBuilderGetBuildPropertiesExpInternal = nullptr;
static decltype(zeRTASBuilderBuildExp)* zeRTASBuilderBuildExpInternal = nullptr;
  
static decltype(zeRTASParallelOperationCreateExp)* zeRTASParallelOperationCreateExpInternal = nullptr;
static decltype(zeRTASParallelOperationDestroyExp)* zeRTASParallelOperationDestroyExpInternal = nullptr; 
static decltype(zeRTASParallelOperationGetPropertiesExp)* zeRTASParallelOperationGetPropertiesExpInternal = nullptr;
static decltype(zeRTASParallelOperationJoinExp)* zeRTASParallelOperationJoinExpInternal = nullptr;

template<typename T>
T find_symbol(void* handle, std::string const& symbol) {
#if defined(__LINUX__)
  T result = (T) dlsym(handle, symbol.c_str());
#else
  T result = (T) GetProcAddress((HMODULE)handle, symbol.c_str());
#endif
  if (!result) {
    throw std::runtime_error("level_zero wrapper: symbol " + symbol + " not found");
  }
  return result;
}

void* load_module() {
#if defined(__LINUX__)
  void* handle = dlopen(ZE_LOADER_NAME_LINUX,RTLD_LAZY);
  if (!handle) {
    throw std::runtime_error("module " ZE_LOADER_NAME_LINUX " not found");
  }
#else
  void* handle = LoadLibraryExA(ZE_LOADER_NAME_WINDOWS,NULL,LOAD_LIBRARY_SEARCH_SYSTEM32);
  if (!handle) {
    throw std::runtime_error("module " ZE_LOADER_NAME_WINDOWS " not found");
  }
#endif
  return handle;
}

void unload_module(void* handle) {
  if (handle) {
#if defined(__LINUX__)
    dlclose(handle);
#else
    FreeLibrary((HMODULE)handle);
#endif
  }
}

ZeWrapper::~ZeWrapper() {
  unload_module(handle);
}

ze_result_t selectLevelZeroRTASBuilder(ze_driver_handle_t hDriver)
{
  if (ZeWrapper::rtas_builder == ZeWrapper::LEVEL_ZERO)
    return ZE_RESULT_SUCCESS;
  
  auto zeRTASBuilderCreateExpTemp = find_symbol<decltype(zeRTASBuilderCreateExp)*>(handle,"zeRTASBuilderCreateExp");
  auto zeRTASBuilderDestroyExpTemp = find_symbol<decltype(zeRTASBuilderDestroyExp)*>(handle,"zeRTASBuilderDestroyExp");
  
  ze_rtas_builder_exp_desc_t builderDesc = { ZE_STRUCTURE_TYPE_RTAS_BUILDER_EXP_DESC };
  ze_rtas_builder_exp_handle_t hBuilder = nullptr;
  ze_result_t err = zeRTASBuilderCreateExpTemp(hDriver, &builderDesc, &hBuilder);

  /* when ZE_RESULT_ERROR_DEPENDENCY_UNAVAILABLE is reported extension cannot get loaded */
  if (err == ZE_RESULT_ERROR_DEPENDENCY_UNAVAILABLE)
    return err;

  if (err == ZE_RESULT_SUCCESS)
    zeRTASBuilderDestroyExpTemp(hBuilder);

  zeRTASBuilderCreateExpInternal = zeRTASBuilderCreateExpTemp;
  zeRTASBuilderDestroyExpInternal = zeRTASBuilderDestroyExpTemp;
  
  zeDriverRTASFormatCompatibilityCheckExpInternal = find_symbol<decltype(zeDriverRTASFormatCompatibilityCheckExp)*>(handle,"zeDriverRTASFormatCompatibilityCheckExp");
  zeRTASBuilderGetBuildPropertiesExpInternal = find_symbol<decltype(zeRTASBuilderGetBuildPropertiesExp)*>(handle,"zeRTASBuilderGetBuildPropertiesExp");
  zeRTASBuilderBuildExpInternal = find_symbol<decltype(zeRTASBuilderBuildExp)*>(handle,"zeRTASBuilderBuildExp");
  
  zeRTASParallelOperationCreateExpInternal = find_symbol<decltype(zeRTASParallelOperationCreateExp)*>(handle,"zeRTASParallelOperationCreateExp");
  zeRTASParallelOperationDestroyExpInternal = find_symbol<decltype(zeRTASParallelOperationDestroyExp)*>(handle,"zeRTASParallelOperationDestroyExp");
  zeRTASParallelOperationGetPropertiesExpInternal = find_symbol<decltype(zeRTASParallelOperationGetPropertiesExp)*>(handle,"zeRTASParallelOperationGetPropertiesExp");
  zeRTASParallelOperationJoinExpInternal = find_symbol<decltype(zeRTASParallelOperationJoinExp)*>(handle,"zeRTASParallelOperationJoinExp");
  
  ZeWrapper::rtas_builder = ZeWrapper::LEVEL_ZERO;
  return ZE_RESULT_SUCCESS;
}

void selectInternalRTASBuilder()
{
#if defined(ZE_RAYTRACING_DISABLE_INTERNAL_BUILDER)
  throw std::runtime_error("internal builder disabled at compile time");
#else
  if (ZeWrapper::rtas_builder == ZeWrapper::INTERNAL)
    return;
  
  zeRTASBuilderCreateExpInternal = &zeRTASBuilderCreateExpImpl;
  zeRTASBuilderDestroyExpInternal = &zeRTASBuilderDestroyExpImpl;
  zeDriverRTASFormatCompatibilityCheckExpInternal = &zeDriverRTASFormatCompatibilityCheckExpImpl;
  zeRTASBuilderGetBuildPropertiesExpInternal = &zeRTASBuilderGetBuildPropertiesExpImpl;
  zeRTASBuilderBuildExpInternal = &zeRTASBuilderBuildExpImpl;
  
  zeRTASParallelOperationCreateExpInternal = &zeRTASParallelOperationCreateExpImpl;
  zeRTASParallelOperationDestroyExpInternal = &zeRTASParallelOperationDestroyExpImpl;
  zeRTASParallelOperationGetPropertiesExpInternal = &zeRTASParallelOperationGetPropertiesExpImpl;
  zeRTASParallelOperationJoinExpInternal = &zeRTASParallelOperationJoinExpImpl;
  
  ZeWrapper::rtas_builder = ZeWrapper::INTERNAL;
#endif
}

ze_result_t ZeWrapper::init()
{
  std::lock_guard<std::mutex> lock(zeWrapperMutex);
  if (handle)
    return ZE_RESULT_SUCCESS;

  try {
    handle = load_module();
    
    zeMemFreeInternal = find_symbol<decltype(zeMemFree)*>(handle, "zeMemFree");
    zeMemAllocSharedInternal = find_symbol<decltype(zeMemAllocShared)*>(handle, "zeMemAllocShared");
    zeDriverGetExtensionPropertiesInternal = find_symbol<decltype(zeDriverGetExtensionProperties)*>(handle, "zeDriverGetExtensionProperties");
    zeDeviceGetPropertiesInternal = find_symbol<decltype(zeDeviceGetProperties)*>(handle, "zeDeviceGetProperties");
    zeDeviceGetModulePropertiesInternal = find_symbol<decltype(zeDeviceGetModuleProperties)*>(handle, "zeDeviceGetModuleProperties");
  }
  catch (std::exception& e) {
    return ZE_RESULT_ERROR_UNKNOWN;
  }
  return ZE_RESULT_SUCCESS;
}

ze_result_t ZeWrapper::initRTASBuilder(ze_driver_handle_t hDriver, RTAS_BUILD_MODE rtas_build_mode)
{
  std::lock_guard<std::mutex> lock(zeWrapperMutex);

  /* only select rtas builder once! */
  if (rtas_builder != RTAS_BUILD_MODE::AUTO)
  {
    if (rtas_build_mode == RTAS_BUILD_MODE::AUTO)
      return ZE_RESULT_SUCCESS;

    if (rtas_builder == rtas_build_mode)
      return ZE_RESULT_SUCCESS;

    return ZE_RESULT_ERROR_UNKNOWN;
  }

  try {
    
    if (rtas_build_mode == RTAS_BUILD_MODE::AUTO)
    {
      try {
        if (selectLevelZeroRTASBuilder(hDriver) != ZE_RESULT_SUCCESS)
          selectInternalRTASBuilder();
      } catch (std::exception& e) {
        selectInternalRTASBuilder();
      }
    }
    
    else if (rtas_build_mode == RTAS_BUILD_MODE::INTERNAL)
      selectInternalRTASBuilder();
    
    else if (rtas_build_mode == RTAS_BUILD_MODE::LEVEL_ZERO)
      return selectLevelZeroRTASBuilder(hDriver);
    
    else
      throw std::runtime_error("internal error");
  }
  catch (std::exception& e) {
    return ZE_RESULT_ERROR_UNKNOWN;
  }
  return ZE_RESULT_SUCCESS;
}

ze_result_t ZeWrapper::zeMemFree(ze_context_handle_t context, void* ptr)
{
  if (!handle || !zeMemFreeInternal)
    throw std::runtime_error("ZeWrapper not initialized, call ZeWrapper::init() first.");
  
  return zeMemFreeInternal(context, ptr);
}

ze_result_t ZeWrapper::zeMemAllocShared(ze_context_handle_t context, const ze_device_mem_alloc_desc_t* descd, const ze_host_mem_alloc_desc_t* desch, size_t s0, size_t s1, ze_device_handle_t ze_handle, void** ptr)
{
  if (!handle || !zeMemAllocSharedInternal)
    throw std::runtime_error("ZeWrapper not initialized, call ZeWrapper::init() first.");
  
  return zeMemAllocSharedInternal(context, descd, desch, s0, s1, ze_handle, ptr);
}

ze_result_t ZeWrapper::zeDriverGetExtensionProperties(ze_driver_handle_t ze_handle, uint32_t* ptr, ze_driver_extension_properties_t* props)
{
  if (!handle || !zeDriverGetExtensionPropertiesInternal)
    throw std::runtime_error("ZeWrapper not initialized, call ZeWrapper::init() first.");
  
  return zeDriverGetExtensionPropertiesInternal(ze_handle, ptr, props);
}

#define VALIDATE(arg) \
  {\
  ze_result_t result = validate(arg);\
  if (result != ZE_RESULT_SUCCESS) return result; \
  }

ze_result_t validate(ze_device_handle_t hDevice)
  {
    if (hDevice == nullptr)
      return ZE_RESULT_ERROR_INVALID_NULL_HANDLE;
    
    return ZE_RESULT_SUCCESS;
  }

ze_result_t validate(ze_rtas_device_exp_properties_t* pProperties)
{ 
  if (pProperties == nullptr)
    return ZE_RESULT_ERROR_INVALID_NULL_POINTER;
  
  if (pProperties->stype != ZE_STRUCTURE_TYPE_RTAS_DEVICE_EXP_PROPERTIES)
    return ZE_RESULT_ERROR_INVALID_ENUMERATION;
  
  //if (!checkDescChain((zet_base_desc_t_*)pProperties))
  //return ZE_RESULT_ERROR_INVALID_ENUMERATION;
  
  return ZE_RESULT_SUCCESS;
}

ze_result_t zeDeviceGetRTASPropertiesExp( const ze_device_handle_t hDevice, ze_rtas_device_exp_properties_t* pProperties )
{
  /* input validation */
  VALIDATE(hDevice);
  VALIDATE(pProperties);
  
  /* fill properties */
  pProperties->flags = 0;
  pProperties->rtasFormat = (ze_rtas_format_exp_t) ZE_RTAS_DEVICE_FORMAT_EXP_INVALID;
  pProperties->rtasBufferAlignment = 128;
  
  /* check for supported device ID */
  ze_device_properties_t device_props{ ZE_STRUCTURE_TYPE_DEVICE_PROPERTIES };
  ze_result_t status = ZeWrapper::zeDeviceGetProperties(hDevice, &device_props);
  if (status != ZE_RESULT_SUCCESS)
    return status;
  
  /* check for Intel vendor */
  const uint32_t vendor_id = device_props.vendorId;
  const uint32_t device_id = device_props.deviceId;
  if (vendor_id != 0x8086) return ZE_RESULT_ERROR_UNKNOWN;
  
  /* disabling of device check through env variable */
  const char* disable_device_check = getenv("EMBREE_DISABLE_DEVICEID_CHECK");
  if (disable_device_check && strcmp(disable_device_check,"1") == 0) {
    pProperties->rtasFormat = (ze_rtas_format_exp_t) ZE_RTAS_DEVICE_FORMAT_EXP_VERSION_1;
    return ZE_RESULT_SUCCESS;
  }
  
  /* DG2 */
  const bool dg2 =
    (0x4F80 <= device_id && device_id <= 0x4F88) ||
    (0x5690 <= device_id && device_id <= 0x5698) ||
    (0x56A0 <= device_id && device_id <= 0x56A6) ||
    (0x56B0 <= device_id && device_id <= 0x56B3) ||
    (0x56C0 <= device_id && device_id <= 0x56C1);
  
  if (dg2) {
    pProperties->rtasFormat = (ze_rtas_format_exp_t) ZE_RTAS_DEVICE_FORMAT_EXP_VERSION_1;
    return ZE_RESULT_SUCCESS;
  }
  
  /* PVC */
  const bool pvc =
    (0x0BD5 <= device_id && device_id <= 0x0BDB) ||
    (device_id == 0x0B69                       );
  
  if (pvc) {
    pProperties->rtasFormat = (ze_rtas_format_exp_t) ZE_RTAS_DEVICE_FORMAT_EXP_VERSION_1;
    return ZE_RESULT_SUCCESS;
  }
  
  /* MTL */
  const bool mtl =
    (device_id == 0x7D40) ||
    (device_id == 0x7D55) ||
    (device_id == 0x7DD5) ||
    (device_id == 0x7D45) ||
    (device_id == 0x7D60);
  
  if (mtl) {
    pProperties->rtasFormat = (ze_rtas_format_exp_t) ZE_RTAS_DEVICE_FORMAT_EXP_VERSION_1;
    return ZE_RESULT_SUCCESS;
  }
  
  return ZE_RESULT_ERROR_UNKNOWN;
}

ze_result_t ZeWrapper::zeDeviceGetProperties(ze_device_handle_t ze_handle, ze_device_properties_t* props)
{
  if (!handle || !zeDeviceGetPropertiesInternal)
    throw std::runtime_error("ZeWrapper not initialized, call ZeWrapper::init() first.");

  if (ZeWrapper::rtas_builder == ZeWrapper::INTERNAL)
  {
    if (props->pNext && ((ze_base_properties_t*)props->pNext)->stype == ZE_STRUCTURE_TYPE_RTAS_DEVICE_EXP_PROPERTIES)
    {
      ze_result_t result = zeDeviceGetRTASPropertiesExp(ze_handle, (ze_rtas_device_exp_properties_t*)props->pNext);
      if (result != ZE_RESULT_SUCCESS) return result;
      
      void* pNext = props->pNext;
      props->pNext = ((ze_base_properties_t*)props->pNext)->pNext;
      result = zeDeviceGetPropertiesInternal(ze_handle, props);
      props->pNext = pNext;
      return result;
    }
  }
    
  return zeDeviceGetPropertiesInternal(ze_handle, props);
}

ze_result_t ZeWrapper::zeDeviceGetModuleProperties(ze_device_handle_t ze_handle, ze_device_module_properties_t* props)
{
  if (!handle || !zeDeviceGetModulePropertiesInternal)
    throw std::runtime_error("ZeWrapper not initialized, call ZeWrapper::init() first.");
  
  return zeDeviceGetModulePropertiesInternal(ze_handle, props);
}

ze_result_t ZeWrapper::zeRTASBuilderCreateExp(ze_driver_handle_t hDriver, const ze_rtas_builder_exp_desc_t *pDescriptor, ze_rtas_builder_exp_handle_t *phBuilder)
{
  if (!handle || !zeRTASBuilderCreateExpInternal)
    throw std::runtime_error("ZeWrapper not initialized, call ZeWrapper::init() first.");
  
  return zeRTASBuilderCreateExpInternal(hDriver,pDescriptor,phBuilder);
}

ze_result_t ZeWrapper::zeRTASBuilderDestroyExp(ze_rtas_builder_exp_handle_t hBuilder)
{
  if (!handle || !zeRTASBuilderDestroyExpInternal)
    throw std::runtime_error("ZeWrapper not initialized, call ZeWrapper::init() first.");
    
  return zeRTASBuilderDestroyExpInternal(hBuilder);
}

ze_result_t ZeWrapper::zeDriverRTASFormatCompatibilityCheckExp( ze_driver_handle_t hDriver,
                                                                 const ze_rtas_format_exp_t accelFormat,
                                                                 const ze_rtas_format_exp_t otherAccelFormat)
{
  if (!handle || !zeDriverRTASFormatCompatibilityCheckExpInternal)
    throw std::runtime_error("ZeWrapper not initialized, call ZeWrapper::init() first.");
  
  return zeDriverRTASFormatCompatibilityCheckExpInternal( hDriver, accelFormat, otherAccelFormat);
}

ze_result_t ZeWrapper::zeRTASBuilderGetBuildPropertiesExp(ze_rtas_builder_exp_handle_t hBuilder,
                                                          const ze_rtas_builder_build_op_exp_desc_t* args,
                                                          ze_rtas_builder_exp_properties_t* pProp)
{
  if (!handle || !zeRTASBuilderGetBuildPropertiesExpInternal)
    throw std::runtime_error("ZeWrapper not initialized, call ZeWrapper::init() first.");
    
  return zeRTASBuilderGetBuildPropertiesExpInternal(hBuilder, args, pProp);
}
  
ze_result_t ZeWrapper::zeRTASBuilderBuildExp(ze_rtas_builder_exp_handle_t hBuilder,
                                             const ze_rtas_builder_build_op_exp_desc_t* args,
                                             void *pScratchBuffer, size_t scratchBufferSizeBytes,
                                             void *pRtasBuffer, size_t rtasBufferSizeBytes,
                                             ze_rtas_parallel_operation_exp_handle_t hParallelOperation,
                                             void *pBuildUserPtr, ze_rtas_aabb_exp_t *pBounds, size_t *pRtasBufferSizeBytes)
{
  if (!handle || !zeRTASBuilderBuildExpInternal)
    throw std::runtime_error("ZeWrapper not initialized, call ZeWrapper::init() first.");
  
  return zeRTASBuilderBuildExpInternal(hBuilder, args, pScratchBuffer, scratchBufferSizeBytes, pRtasBuffer, rtasBufferSizeBytes,
                                       hParallelOperation, pBuildUserPtr, pBounds, pRtasBufferSizeBytes);
}

ze_result_t ZeWrapper::zeRTASParallelOperationCreateExp(ze_driver_handle_t hDriver, ze_rtas_parallel_operation_exp_handle_t* phParallelOperation)
{
  if (!handle || !zeRTASParallelOperationCreateExpInternal)
    throw std::runtime_error("ZeWrapper not initialized, call ZeWrapper::init() first.");

  return zeRTASParallelOperationCreateExpInternal(hDriver, phParallelOperation);
}

ze_result_t ZeWrapper::zeRTASParallelOperationDestroyExp( ze_rtas_parallel_operation_exp_handle_t hParallelOperation )
{
  if (!handle || !zeRTASParallelOperationDestroyExpInternal)
    throw std::runtime_error("ZeWrapper not initialized, call ZeWrapper::init() first.");
  
  return zeRTASParallelOperationDestroyExpInternal( hParallelOperation );
};

ze_result_t ZeWrapper::zeRTASParallelOperationGetPropertiesExp( ze_rtas_parallel_operation_exp_handle_t hParallelOperation, ze_rtas_parallel_operation_exp_properties_t* pProperties )
{
  if (!handle || !zeRTASParallelOperationGetPropertiesExpInternal)
    throw std::runtime_error("ZeWrapper not initialized, call ZeWrapper::init() first.");
  
  return zeRTASParallelOperationGetPropertiesExpInternal( hParallelOperation, pProperties );
}
 
ze_result_t ZeWrapper::zeRTASParallelOperationJoinExp( ze_rtas_parallel_operation_exp_handle_t hParallelOperation)
{
  if (!handle || !zeRTASParallelOperationJoinExpInternal)
    throw std::runtime_error("ZeWrapper not initialized, call ZeWrapper::init() first.");
  
  return zeRTASParallelOperationJoinExpInternal(hParallelOperation);
}
