#define LOG_MODULE PacketLogModuleArpLayer

#include "ArpLayer.h"

#include "EthLayer.h"

#include "EndianPortable.h"

namespace pcpp

{

  ArpLayer::ArpLayer(ArpOpcode opCode, const MacAddress& senderMacAddr, const IPv4Address& senderIpAddr,

                     const MacAddress& targetMacAddr, const IPv4Address& targetIpAddr)

  {

    constexpr size_t headerLen = sizeof(arphdr);

    m_DataLen = headerLen;

    m_Data = new uint8_t[headerLen]{};  // zero-initialized

    m_Protocol = ARP;

    arphdr* arpHeader = getArpHeader();

    arpHeader->opcode = htobe16(static_cast<uint16_t>(opCode));

    senderMacAddr.copyTo(arpHeader->senderMacAddr);

    targetMacAddr.copyTo(arpHeader->targetMacAddr);

    arpHeader->senderIpAddr = senderIpAddr.toInt();

    arpHeader->targetIpAddr = targetIpAddr.toInt();

  }

  // This constructor zeroes the target MAC address for ARP requests to keep backward compatibility.

  ArpLayer::ArpLayer(ArpOpcode opCode, const MacAddress& senderMacAddr, const MacAddress& targetMacAddr,

                     const IPv4Address& senderIpAddr, const IPv4Address& targetIpAddr)

      : ArpLayer(opCode, senderMacAddr, senderIpAddr, opCode == ARP_REQUEST ? MacAddress::Zero : targetMacAddr,

                 targetIpAddr)

  {}

  ArpLayer::ArpLayer(ArpRequest const& arpRequest)

      : ArpLayer(ARP_REQUEST, arpRequest.senderMacAddr, arpRequest.senderIpAddr, MacAddress::Zero,

                 arpRequest.targetIpAddr)

  {}

  ArpLayer::ArpLayer(ArpReply const& arpReply)

      : ArpLayer(ARP_REPLY, arpReply.senderMacAddr, arpReply.senderIpAddr, arpReply.targetMacAddr,

                 arpReply.targetIpAddr)

  {}

  ArpLayer::ArpLayer(GratuitousArpRequest const& gratuitousArpRequest)

      : ArpLayer(ARP_REQUEST, gratuitousArpRequest.senderMacAddr, gratuitousArpRequest.senderIpAddr,

                 MacAddress::Broadcast, gratuitousArpRequest.senderIpAddr)

  {}

  ArpLayer::ArpLayer(GratuitousArpReply const& gratuitousArpReply)

      : ArpLayer(ARP_REPLY, gratuitousArpReply.senderMacAddr, gratuitousArpReply.senderIpAddr, MacAddress::Broadcast,

                 gratuitousArpReply.senderIpAddr)

  {}

  ArpOpcode ArpLayer::getOpcode() const

  {

    return static_cast<ArpOpcode>(be16toh(getArpHeader()->opcode));

  }

  void ArpLayer::computeCalculateFields()

  {

    arphdr* arpHeader = getArpHeader();

    arpHeader->hardwareType = htobe16(1);  // Ethernet

    arpHeader->hardwareSize = 6;

    arpHeader->protocolType = htobe16(PCPP_ETHERTYPE_IP);  // assume IPv4 over ARP

    arpHeader->protocolSize = 4;                           // assume IPv4 over ARP

  }

  ArpMessageType ArpLayer::getMessageType() const

  {

    switch (getOpcode())

    {

    case ArpOpcode::ARP_REQUEST:

    {

      if (getTargetMacAddress() == MacAddress::Broadcast && getSenderIpAddr() == getTargetIpAddr())

      {

        return ArpMessageType::GratuitousRequest;

      }

      return ArpMessageType::Request;

    }

    case ArpOpcode::ARP_REPLY:

    {

      if (getTargetMacAddress() == MacAddress::Broadcast && getSenderIpAddr() == getTargetIpAddr())

      {

        return ArpMessageType::GratuitousReply;

      }

      return ArpMessageType::Reply;

    }

    default:

      return ArpMessageType::Unknown;

    }

  }

  bool ArpLayer::isRequest() const

  {

    return getOpcode() == pcpp::ArpOpcode::ARP_REQUEST;

  }

  bool ArpLayer::isReply() const

  {

    return getOpcode() == pcpp::ArpOpcode::ARP_REPLY;

  }

  std::string ArpLayer::toString() const

  {

    switch (getOpcode())

    {

    case ArpOpcode::ARP_REQUEST:

      return "ARP Layer, ARP request, who has " + getTargetIpAddr().toString() + " ? Tell " +

             getSenderIpAddr().toString();

    case ArpOpcode::ARP_REPLY:

      return "ARP Layer, ARP reply, " + getSenderIpAddr().toString() + " is at " +

             getSenderMacAddress().toString();

    default:

      return "ARP Layer, unknown opcode (" + std::to_string(getOpcode()) + ")";

    }

  }

}  // namespace pcpp