#pragma once

#include "Layer.h"

/// @file

/// @namespace pcpp

/// @brief The main namespace for the PcapPlusPlus lib

namespace pcpp

{

/// IPv4 protocol *

#define PCPP_BSD_AF_INET 2

/// XEROX NS protocols

#define PCPP_BSD_AF_NS 6

/// ISO

#define PCPP_BSD_AF_ISO 7

/// AppleTalk

#define PCPP_BSD_AF_APPLETALK 16

/// IPX

#define PCPP_BSD_AF_IPX 23

/// OpenBSD (and probably NetBSD), BSD/OS IPv6

#define PCPP_BSD_AF_INET6_BSD 24

/// FreeBSD IPv6

#define PCPP_BSD_AF_INET6_FREEBSD 28

/// Darwin IPv6

#define PCPP_BSD_AF_INET6_DARWIN 30

  /// @class NullLoopbackLayer

  /// Represents a Null/Loopback layer

  class NullLoopbackLayer : public Layer

  {

  public:

    /// A constructor that creates the layer from an existing packet raw data

    /// @param[in] data A pointer to the raw data

    /// @param[in] dataLen Size of the data in bytes

    /// @param[in] packet A pointer to the Packet instance where layer will be stored in

    NullLoopbackLayer(uint8_t* data, size_t dataLen, Packet* packet)

        : Layer(data, dataLen, nullptr, packet, NULL_LOOPBACK)

    {}

    /// A constructor that allocates a new Null/Loopback header

    /// @param[in] family The family protocol to set

    explicit NullLoopbackLayer(uint32_t family);

    /// A destructor for this layer (does nothing)

    ~NullLoopbackLayer() override = default;

    /// @return The protocol family in this layer

    uint32_t getFamily() const;

    /// Set a protocol family

    /// @param[in] family The family protocol to set

    void setFamily(uint32_t family);

    // implement abstract methods

    /// Identifies the next layers by family:

    /// - for ::PCPP_BSD_AF_INET the next layer is IPv4Layer

    /// - for ::PCPP_BSD_AF_INET6_BSD, ::PCPP_BSD_AF_INET6_FREEBSD, ::PCPP_BSD_AF_INET6_DARWIN the next layer is

    /// IPv6Layer

    /// - for other values the next layer in PayloadLayer (unknown protocol)

    void parseNextLayer() override;

    /// @return Size of Null/Loopback header = 4B

    size_t getHeaderLen() const override

    {

      return sizeof(uint32_t);

    }

    /// Does nothing for this layer

    void computeCalculateFields() override

    {}

    std::string toString() const override;

    OsiModelLayer getOsiModelLayer() const override

    {

      return OsiModelDataLinkLayer;

    }

    /// @brief Check if the data passes minimal validity checks for Null/Loopback layer

    /// @param data A pointer to the data

    /// @param dataLen Size of the data in bytes

    /// @return True if the data can represent a valid Null/Loopback layer, false otherwise

    bool static isDataValid(const uint8_t* data, size_t dataLen)

    {

      return data != nullptr && dataLen >= sizeof(uint32_t);

    }

    /// @struct SerializedFields

    /// Fields written by NullLoopbackLayer's serializeLayer(), in addition to

    /// Layer::SerializedFields.

    struct SerializedFields : Layer::SerializedFields

    {

      /// @return All field descriptors for NullLoopbackLayer

      static std::vector<FieldDescriptor> all()

      {

        auto result = Layer::SerializedFields::all();

        std::initializer_list<FieldDescriptor> extra{ Family };

        std::copy(extra.begin(), extra.end(), std::back_inserter(result));

        return result;

      }

      /// @brief Protocol family (AF_* value) of the payload

      static const FieldDescriptor Family;

    };

  protected:

    void serializeLayer(ObjectScope& serializer) const override;

  };

}  // namespace pcpp