#define LOG_MODULE PacketLogModuleDhcpV6Layer

#include "DhcpV6Layer.h"

#include "Logger.h"

#include "GeneralUtils.h"

#include "EndianPortable.h"

namespace pcpp

{

  DhcpV6OptionType DhcpV6Option::getType() const

  {

    if (m_Data == nullptr)

      return DhcpV6OptionType::DHCPV6_OPT_UNKNOWN;

    uint16_t optionType = be16toh(m_Data->recordType);

    if (optionType <= 62 && optionType != 10 && optionType != 35 && optionType != 57 && optionType != 58)

    {

      return static_cast<DhcpV6OptionType>(optionType);

    }

    if (optionType == 65 || optionType == 66 || optionType == 68 || optionType == 79 || optionType == 112)

    {

      return static_cast<DhcpV6OptionType>(optionType);

    }

    return DHCPV6_OPT_UNKNOWN;

  }

  std::string DhcpV6Option::getValueAsHexString() const

  {

    if (m_Data == nullptr)

      return "";

    return byteArrayToHexString(m_Data->recordValue, getDataSize());

  }

  size_t DhcpV6Option::getTotalSize() const

  {

    if (m_Data == nullptr)

      return 0;

    return 2 * sizeof(uint16_t) + be16toh(m_Data->recordLen);

  }

  size_t DhcpV6Option::getDataSize() const

  {

    if (m_Data == nullptr)

      return 0;

    return static_cast<size_t>(be16toh(m_Data->recordLen));

  }

  DhcpV6Option DhcpV6OptionBuilder::build() const

  {

    if (m_RecType == 0)

      return DhcpV6Option(nullptr);

    size_t optionSize = 2 * sizeof(uint16_t) + m_RecValueLen;

    uint8_t* recordBuffer = new uint8_t[optionSize];

    uint16_t optionTypeVal = htobe16(static_cast<uint16_t>(m_RecType));

    uint16_t optionLength = htobe16(static_cast<uint16_t>(m_RecValueLen));

    memcpy(recordBuffer, &optionTypeVal, sizeof(uint16_t));

    memcpy(recordBuffer + sizeof(uint16_t), &optionLength, sizeof(uint16_t));

    if (optionSize > 0 && m_RecValue != nullptr)

      memcpy(recordBuffer + 2 * sizeof(uint16_t), m_RecValue, m_RecValueLen);

    return DhcpV6Option(recordBuffer);

  }

  DhcpV6Layer::DhcpV6Layer(uint8_t* data, size_t dataLen, Layer* prevLayer, Packet* packet)

      : Layer(data, dataLen, prevLayer, packet, DHCPv6)

  {}

  DhcpV6Layer::DhcpV6Layer(DhcpV6MessageType messageType, uint32_t transactionId)

  {

    m_DataLen = sizeof(dhcpv6_header);

    m_Data = new uint8_t[m_DataLen];

    memset(m_Data, 0, m_DataLen);

    m_Protocol = DHCPv6;

    setMessageType(messageType);

    setTransactionID(transactionId);

  }

  DhcpV6MessageType DhcpV6Layer::getMessageType() const

  {

    uint8_t messageType = getDhcpHeader()->messageType;

    if (messageType > 13)

    {

      return DHCPV6_UNKNOWN_MSG_TYPE;

    }

    return static_cast<DhcpV6MessageType>(messageType);

  }

  std::string DhcpV6Layer::getMessageTypeAsString() const

  {

    DhcpV6MessageType messageType = getMessageType();

    switch (messageType)

    {

    case DHCPV6_SOLICIT:

      return "Solicit";

    case DHCPV6_ADVERTISE:

      return "Advertise";

    case DHCPV6_REQUEST:

      return "Request";

    case DHCPV6_CONFIRM:

      return "Confirm";

    case DHCPV6_RENEW:

      return "Renew";

    case DHCPV6_REBIND:

      return "Rebind";

    case DHCPV6_REPLY:

      return "Reply";

    case DHCPV6_RELEASE:

      return "Release";

    case DHCPV6_DECLINE:

      return "Decline";

    case DHCPV6_RECONFIGURE:

      return "Reconfigure";

    case DHCPV6_INFORMATION_REQUEST:

      return "Information-Request";

    case DHCPV6_RELAY_FORWARD:

      return "Relay-Forward";

    case DHCPV6_RELAY_REPLY:

      return "Relay-Reply";

    default:

      return "Unknown";

    }

  }

  void DhcpV6Layer::setMessageType(DhcpV6MessageType messageType)

  {

    getDhcpHeader()->messageType = static_cast<uint8_t>(messageType);

  }

  uint32_t DhcpV6Layer::getTransactionID() const

  {

    dhcpv6_header* hdr = getDhcpHeader();

    uint32_t result = hdr->transactionId1 << 16 | hdr->transactionId2 << 8 | hdr->transactionId3;

    return result;

  }

  void DhcpV6Layer::setTransactionID(uint32_t transactionId) const

  {

    dhcpv6_header* hdr = getDhcpHeader();

    hdr->transactionId1 = (transactionId >> 16) & 0xff;

    hdr->transactionId2 = (transactionId >> 8) & 0xff;

    hdr->transactionId3 = transactionId & 0xff;

  }

  DhcpV6Option DhcpV6Layer::getFirstOptionData() const

  {

    return m_OptionReader.getFirstTLVRecord(getOptionsBasePtr(), getHeaderLen() - sizeof(dhcpv6_header));

  }

  DhcpV6Option DhcpV6Layer::getNextOptionData(DhcpV6Option dhcpv6Option) const

  {

    return m_OptionReader.getNextTLVRecord(dhcpv6Option, getOptionsBasePtr(),

                                           getHeaderLen() - sizeof(dhcpv6_header));

  }

  DhcpV6Option DhcpV6Layer::getOptionData(DhcpV6OptionType option) const

  {

    return m_OptionReader.getTLVRecord(static_cast<uint32_t>(option), getOptionsBasePtr(),

                                       getHeaderLen() - sizeof(dhcpv6_header));

  }

  size_t DhcpV6Layer::getOptionCount() const

  {

    return m_OptionReader.getTLVRecordCount(getOptionsBasePtr(), getHeaderLen() - sizeof(dhcpv6_header));

  }

  DhcpV6Option DhcpV6Layer::addOptionAt(const DhcpV6OptionBuilder& optionBuilder, int offset)

  {

    DhcpV6Option newOpt = optionBuilder.build();

    if (newOpt.isNull())

    {

      PCPP_LOG_ERROR("Cannot build new option");

      return DhcpV6Option(nullptr);

    }

    size_t sizeToExtend = newOpt.getTotalSize();

    if (!extendLayer(offset, sizeToExtend))

    {

      PCPP_LOG_ERROR("Could not extend DhcpLayer in [" << newOpt.getTotalSize() << "] bytes");

      newOpt.purgeRecordData();

      return DhcpV6Option(nullptr);

    }

    memcpy(m_Data + offset, newOpt.getRecordBasePtr(), newOpt.getTotalSize());

    uint8_t* newOptPtr = m_Data + offset;

    m_OptionReader.changeTLVRecordCount(1);

    newOpt.purgeRecordData();

    return DhcpV6Option(newOptPtr);

  }

  DhcpV6Option DhcpV6Layer::addOption(const DhcpV6OptionBuilder& optionBuilder)

  {

    return addOptionAt(optionBuilder, getHeaderLen());

  }

  DhcpV6Option DhcpV6Layer::addOptionAfter(const DhcpV6OptionBuilder& optionBuilder, DhcpV6OptionType optionType)

  {

    int offset = 0;

    DhcpV6Option prevOpt = getOptionData(optionType);

    if (prevOpt.isNull())

    {

      PCPP_LOG_ERROR("Option type " << optionType << " doesn't exist in layer");

      return DhcpV6Option(nullptr);

    }

    offset = prevOpt.getRecordBasePtr() + prevOpt.getTotalSize() - m_Data;

    return addOptionAt(optionBuilder, offset);

  }

  DhcpV6Option DhcpV6Layer::addOptionBefore(const DhcpV6OptionBuilder& optionBuilder, DhcpV6OptionType optionType)

  {

    int offset = 0;

    DhcpV6Option nextOpt = getOptionData(optionType);

    if (nextOpt.isNull())

    {

      PCPP_LOG_ERROR("Option type " << optionType << " doesn't exist in layer");

      return DhcpV6Option(nullptr);

    }

    offset = nextOpt.getRecordBasePtr() - m_Data;

    return addOptionAt(optionBuilder, offset);

  }

  bool DhcpV6Layer::removeOption(DhcpV6OptionType optionType)

  {

    DhcpV6Option optToRemove = getOptionData(optionType);

    if (optToRemove.isNull())

    {

      return false;

    }

    int offset = optToRemove.getRecordBasePtr() - m_Data;

    if (!shortenLayer(offset, optToRemove.getTotalSize()))

    {

      return false;

    }

    m_OptionReader.changeTLVRecordCount(-1);

    return true;

  }

  bool DhcpV6Layer::removeAllOptions()

  {

    int offset = sizeof(dhcpv6_header);

    if (!shortenLayer(offset, getHeaderLen() - offset))

      return false;

    m_OptionReader.changeTLVRecordCount(0 - getOptionCount());

    return true;

  }

  std::string DhcpV6Layer::toString() const

  {

    return "DHCPv6 Layer, " + getMessageTypeAsString() + " message";

  }

}  // namespace pcpp