/* Copyright 2021 The TensorFlow Authors. All Rights Reserved.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
==============================================================================*/

// This file implements the Delegate Plugin for the GPU Delegate.

#include "tensorflow/lite/core/acceleration/configuration/c/gpu_plugin.h"

#include <memory>

#include "tensorflow/lite/acceleration/configuration/configuration_generated.h"
#include "tensorflow/lite/acceleration/configuration/gpu_plugin.h"
#include "tensorflow/lite/core/acceleration/configuration/c/delegate_plugin.h"
#include "tensorflow/lite/core/c/common.h"

#if TFLITE_SUPPORTS_GPU_DELEGATE
#include "tensorflow/lite/delegates/gpu/delegate.h"
#elif defined(REAL_IPHONE_DEVICE)
#include "tensorflow/lite/delegates/gpu/metal_delegate.h"
#endif

extern "C" {

static TfLiteDelegate* CreateDelegate(const void* settings) {
  const ::tflite::TFLiteSettings* tflite_settings =
      static_cast<const ::tflite::TFLiteSettings*>(settings);
  tflite::delegates::GpuPlugin gpu_plugin(*tflite_settings);
#if TFLITE_SUPPORTS_GPU_DELEGATE
  return TfLiteGpuDelegateV2Create(&gpu_plugin.Options());
#elif defined(REAL_IPHONE_DEVICE)
  return TFLGpuDelegateCreate(&gpu_plugin.Options());
#else
  return nullptr;
#endif
}

static void DestroyDelegate(TfLiteDelegate* delegate) {
#if TFLITE_SUPPORTS_GPU_DELEGATE
  TfLiteGpuDelegateV2Delete(delegate);
#elif defined(REAL_IPHONE_DEVICE)
  TFLGpuDelegateDelete(delegate);
#endif
}

static int DelegateErrno(TfLiteDelegate* from_delegate) { return 0; }

static constexpr TfLiteDelegatePlugin kPluginCApi{
    CreateDelegate,
    DestroyDelegate,
    DelegateErrno,
};

const TfLiteDelegatePlugin* TfLiteGpuDelegatePluginCApi() {
  return &kPluginCApi;
}

}  // extern "C"
