/* Copyright (c) 2021 PaddlePaddle 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. */

#pragma once

#include <string>
#include <unordered_map>
#include <vector>

#include "paddle/fluid/framework/framework.pb.h"
#include "paddle/fluid/framework/op_kernel_type.h"
#include "paddle/fluid/framework/tensor.h"
#include "paddle/fluid/imperative/type_defs.h"
#include "paddle/fluid/platform/macros.h"
#include "paddle/fluid/platform/place.h"
#include "paddle/pten/api/include/core.h"
#include "paddle/pten/hapi/lib/utils/tensor_utils.h"
#include "paddle/utils/flat_hash_map.h"
#include "paddle/utils/small_vector.h"

namespace paddle {
namespace framework {

/* Kernel Key translate */

OpKernelType TransPtenKernelKeyToOpKernelType(
    const pten::KernelKey& kernel_key);
pten::KernelKey TransOpKernelTypeToPtenKernelKey(
    const OpKernelType& kernel_type);

/* Kernel Args parse */

struct KernelSignature {
  std::string name;
  KernelArgsTuple args;

  KernelSignature() = default;
  KernelSignature(std::string&& kernel_name,
                  paddle::SmallVector<std::string>&& inputs,
                  paddle::SmallVector<std::string>&& attrs,
                  paddle::SmallVector<std::string>&& outputs)
      : name(std::move(kernel_name)),
        args(std::make_tuple(inputs, attrs, outputs)) {}
  KernelSignature(const std::string& kernel_name,
                  const paddle::SmallVector<std::string>& inputs,
                  const paddle::SmallVector<std::string>& attrs,
                  const paddle::SmallVector<std::string>& outputs)
      : name(kernel_name), args(std::make_tuple(inputs, attrs, outputs)) {}
};

// TODO(chenweihang): we can generate this map by proto info in compile time
class KernelSignatureMap {
 public:
  static KernelSignatureMap& Instance() {
    static KernelSignatureMap g_kernel_signature_map;
    return g_kernel_signature_map;
  }

  bool Has(const std::string& op_type) const {
    return map_.find(op_type) != map_.end();
  }

  void Emplace(const std::string& op_type, KernelSignature&& signature) {
    if (!Has(op_type)) {
      map_.emplace(op_type, signature);
    }
  }

  const KernelSignature& Get(const std::string& op_type) const {
    auto it = map_.find(op_type);
    PADDLE_ENFORCE_NE(
        it, map_.end(),
        platform::errors::NotFound(
            "Operator `%s`'s kernel signature is not registered.", op_type));
    return it->second;
  }

 private:
  KernelSignatureMap() = default;
  paddle::flat_hash_map<std::string, KernelSignature> map_;

  DISABLE_COPY_AND_ASSIGN(KernelSignatureMap);
};

class KernelArgsNameMaker {
 public:
  virtual ~KernelArgsNameMaker() {}
  virtual const paddle::SmallVector<std::string>& GetInputArgsNames() = 0;
  virtual const paddle::SmallVector<std::string>& GetOutputArgsNames() = 0;
  virtual const paddle::SmallVector<std::string>& GetAttrsArgsNames() = 0;
};

class KernelArgsNameMakerByOpProto : public KernelArgsNameMaker {
 public:
  explicit KernelArgsNameMakerByOpProto(framework::proto::OpProto* op_proto)
      : op_proto_(op_proto) {}

  ~KernelArgsNameMakerByOpProto() {}

  const paddle::SmallVector<std::string>& GetInputArgsNames() override;
  const paddle::SmallVector<std::string>& GetOutputArgsNames() override;
  const paddle::SmallVector<std::string>& GetAttrsArgsNames() override;

  KernelSignature GetKernelSignature();

 private:
  framework::proto::OpProto* op_proto_;

  paddle::SmallVector<std::string> input_names_;
  paddle::SmallVector<std::string> output_names_;
  paddle::SmallVector<std::string> attr_names_;
};

std::string KernelSignatureToString(const KernelSignature& signature);

}  // namespace framework
}  // namespace paddle