text: // Copyright (c) 2020 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 <memory>
  #include <string>
  #include <vector>
  #include "lite/core/model/base/var_desc.h"
  #include "lite/model_parser/flatbuffers/framework_generated.h"
  #include "lite/model_parser/flatbuffers/traits.h"
  #include "lite/utils/all.h"
  
  namespace paddle {
  namespace lite {
  namespace fbs {
  
  class VarDescView : public VarDescAPI {
   public:
    explicit VarDescView(proto::VarDesc const* desc) : desc_(desc) {}
  
    std::string Name() const override { return desc_->name()->str(); }
  
    VarDescAPI::Type GetType() const override {
      return ConvertVarType(desc_->type()->type());
    }
  
    bool Persistable() const override { return desc_->persistable(); }
  
    std::vector<int64_t> GetShape() const override {
      const auto& dims = desc_->type()->lod_tensor()->tensor()->dims();
      std::vector<int64_t> dims_vec;
      dims_vec.resize(dims->size());
      for (size_t i = 0; i < dims->size(); ++i) {
        dims_vec[i] = dims->operator[](i);
      }
      return dims_vec;
    }
  
    VarDescAPI::Type GetDataType() const {
      CHECK(GetType() == VarDescAPI::Type::LOD_TENSOR);
      return ConvertVarType(desc_->type()->lod_tensor()->tensor()->data_type());
    }
  
   private:
    proto::VarDesc const* desc_;
  
    // To reduce overhead, we expect to use namespace aliasing to make cpp::Desc
    // and flatbuffers::Desc replace each other. However, there is no direct
    // inheritance relationship between the two data types, and the read-only
    // version of flatbuffers lacks some write implementations. Therefore, at
    // present, we are temporarily providing a default interface that triggers
    // execution-time errors to avoid type ambiguity and compile-time errors
    // caused by different building options.
  
   public:
    VarDescView() = default;
    void SetDataType(Type data_type) { LITE_MODEL_INTERFACE_NOT_IMPLEMENTED; }
    void SetShape(const std::vector<int64_t>& dims) override {
      LITE_MODEL_INTERFACE_NOT_IMPLEMENTED;
    }
  
   private:
    std::vector<int64_t> shape_;
  };
  
  #ifdef LITE_WITH_FLATBUFFERS_DESC
  class VarDesc : public VarDescAPI {
   public:
    VarDesc() : owned_(true), desc_(new proto::VarDescT()) {}
  
    explicit VarDesc(proto::VarDescT* desc) : desc_(desc) {
      CHECK(desc_);
      InitType();
    }
  
    std::string Name() const override { return desc_->name; }
  
    void SetName(std::string name) override { desc_->name = name; }
  
    Type GetType() const override { return ConvertVarType(type_->type); }
  
    void SetType(Type type) override { type_->type = ConvertVarType(type); }
  
    void SetDataType(Type type) {
      type_->lod_tensor->tensor->data_type = ConvertVarType(type);
    }
  
    Type GetDataType() const {
      return ConvertVarType(type_->lod_tensor->tensor->data_type);
    }
  
    bool Persistable() const override { return desc_->persistable; }
  
    void SetPersistable(bool persistable) override {
      desc_->persistable = persistable;
    }
  
    std::vector<int64_t> GetShape() const override {
      return type_->lod_tensor->tensor->dims;
    }
  
    void SetShape(const std::vector<int64_t>& dims) override {
      type_->lod_tensor->tensor->dims = dims;
    }
  
    proto::VarDescT* raw_desc() { return desc_; }
  
    ~VarDesc() {
      if (owned_) {
        delete desc_;
      }
    }
  
   private:
    void InitType() {
      if (!desc_->type) {
        desc_->type = std::unique_ptr<proto::VarTypeT>(new proto::VarTypeT());
        desc_->type->lod_tensor =
            std::unique_ptr<proto::VarType_::LoDTensorDescT>(
                new proto::VarType_::LoDTensorDescT());
        desc_->type->lod_tensor->tensor =
            std::unique_ptr<proto::VarType_::TensorDescT>(
                new proto::VarType_::TensorDescT());
      }
      type_ = desc_->type.get();
    }
    bool owned_{false};
    proto::VarDescT* desc_{nullptr};
    paddle::lite::fbs::proto::VarTypeT* type_{nullptr};
  };
  #endif  // LITE_WITH_FLATBUFFERS_DESC
  
  }  // namespace fbs
  }  // namespace lite
  }  // namespace paddle
  