iflytoplinuxsdk_ptdv1/core/basic/any.hpp

//
// Created by zwsd
//

#pragma once
#include <algorithm>
#include <fstream>
#include <iostream>
#include <list>
#include <map>
#include <memory>
#include <set>
#include <sstream>
#include <string>
#include <typeindex>
#include <typeinfo>
#include <vector>

/**
 * @brief
 *
 * service: ServiceContrainer
 *
 * 监听事件:
 * 依赖状态:
 * 依赖服务:
 * 作用:
 *
 */
//    std::shared_ptr<Buffer> buf(new Buffer());
//    Any any(buf);
//    std::shared_ptr<Buffer> b = any.Get<std::shared_ptr<Buffer>>();
//    assert(buf.get() == b.get());
namespace iflytop {
namespace core {
using namespace std;

class Any {
 public:
  Any() : content_(nullptr) {}
  ~Any() { delete content_; }

  template <typename ValueType>
  explicit Any(const ValueType& value) : content_(new AnyHolder<ValueType>(value)) {}

  Any(const Any& other) : content_(other.content_ ? other.content_->clone() : nullptr) {}

 public:
  Any& swap(Any& rhs) {
    std::swap(content_, rhs.content_);
    return *this;
  }

  template <typename ValueType>
  Any& operator=(const ValueType& rhs) {
    Any(rhs).swap(*this);
    return *this;
  }

  Any& operator=(const Any& rhs) {
    Any(rhs).swap(*this);
    return *this;
  }

  bool IsEmpty() const { return !content_; }

  const std::type_info& GetType() const { return content_ ? content_->GetType() : typeid(void); }

  template <typename ValueType>
  ValueType operator()() const {
    return Get<ValueType>();
  }

  template <typename ValueType>
  ValueType Get() const {
    if (GetType() == typeid(ValueType)) {
      return static_cast<Any::AnyHolder<ValueType>*>(content_)->held_;
    } else {
      return ValueType();
    }
  }

 protected:
  class AnyPlaceHolder {
   public:
    virtual ~AnyPlaceHolder() {}

   public:
    virtual const std::type_info& GetType() const = 0;
    virtual AnyPlaceHolder*       clone() const   = 0;
  };

  template <typename ValueType>
  class AnyHolder : public AnyPlaceHolder {
   public:
    AnyHolder(const ValueType& value) : held_(value) {}

    virtual const std::type_info& GetType() const { return typeid(ValueType); }

    virtual AnyPlaceHolder* clone() const { return new AnyHolder(held_); }

    ValueType held_;
  };

 protected:
  AnyPlaceHolder* content_;
  template <typename ValueType>
  friend ValueType* any_cast(Any*);
};

template <typename ValueType>
ValueType* any_cast(Any* any) {
  if (any && any->GetType() == typeid(ValueType)) {
    return &(static_cast<Any::AnyHolder<ValueType>*>(any->content_)->held_);
  }

  return nullptr;
}

template <typename ValueType>
const ValueType* any_cast(const Any* any) {
  return any_cast<ValueType>(const_cast<Any*>(any));
}

template <typename ValueType>
ValueType any_cast(const Any& any) {
  const ValueType* result = any_cast<ValueType>(&any);
  assert(result);

  if (!result) {
    return ValueType();
  }

  return *result;
}

}  // namespace core
}  // namespace iflytop