#pragma once

#include "Layer.h"

#include <unordered_set>

/// @file

/// @namespace pcpp

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

namespace pcpp

{

  /// @class SomeIpLayer

  /// Represents a SOME/IP protocol layer

  class SomeIpLayer : public Layer

  {

  public:

    /// SOME/IP message types

    enum class MsgType : uint8_t

    {

      /// A request expecting a response (even void)

      REQUEST = 0x00,

      /// Acknowledgment for REQUEST(optional)

      REQUEST_ACK = 0x40,

      /// A fire&forget request

      REQUEST_NO_RETURN = 0x01,

      /// Acknowledgment for REQUEST_NO_RETURN(informational)

      REQUEST_NO_RETURN_ACK = 0x41,

      /// A request of a notification expecting no response

      NOTIFICATION = 0x02,

      /// Acknowledgment for NOTIFICATION(informational)

      NOTIFICATION_ACK = 0x42,

      /// The response message

      RESPONSE = 0x80,

      /// The Acknowledgment for RESPONSE(informational)

      RESPONSE_ACK = 0xC0,

      /// The response containing an error

      ERRORS = 0x81,

      /// Acknowledgment for ERROR(informational)

      ERROR_ACK = 0xC1,

      /// A TP request expecting a response (even void)

      TP_REQUEST = 0x20,

      /// A TP fire&forget request

      TP_REQUEST_NO_RETURN = 0x21,

      /// A TP request of a notification/event callback expecting no response

      TP_NOTIFICATION = 0x22,

      /// The TP response message

      TP_RESPONSE = 0xa0,

      /// The TP response containing an error

      TP_ERROR = 0xa1,

    };

    /// @struct someiphdr

    /// Represents a SOME/IP protocol header

#pragma pack(push, 1)

    struct someiphdr

    {

      /// Service ID

      uint16_t serviceID;

      /// Method ID. Most significant bit 0 when E2E communication. 1 when SOME/IP event

      uint16_t methodID;

      /// Length. Also covers payload. Excludes serviceID, methodID and length field itself

      uint32_t length;

      /// Client ID

      uint16_t clientID;

      /// Session ID

      uint16_t sessionID;

      /// Protocol Version

      uint8_t protocolVersion;

      /// Interface Version

      uint8_t interfaceVersion;

      /// Message Type

      uint8_t msgType;

      /// Return Code

      uint8_t returnCode;

    };

#pragma pack(pop)

    static_assert(sizeof(someiphdr) == 16, "someiphdr size is not 16 bytes");

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

    /// @param[in] data A pointer to the raw data (will be casted to someiphdr)

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

    /// @param[in] prevLayer A pointer to the previous layer

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

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

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

    {}

    /// Construct a new layer object

    /// @param[in] serviceID Service ID

    /// @param[in] methodID Method ID

    /// @param[in] clientID Client ID

    /// @param[in] sessionID Session ID

    /// @param[in] interfaceVersion Interface Version

    /// @param[in] type Type of the message

    /// @param[in] returnCode Return Code

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

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

    /// holds the reference to a data buffer. This option can be used to reduce the number of copies to generate

    /// packets.

    SomeIpLayer(uint16_t serviceID, uint16_t methodID, uint16_t clientID, uint16_t sessionID,

                uint8_t interfaceVersion, MsgType type, uint8_t returnCode, const uint8_t* const data = nullptr,

                size_t dataLen = 0);

    /// Destroy the layer object

    ~SomeIpLayer() override = default;

    /// A static method that creates a SOME/IP or SOME/IP-TP layer from packet raw data. Returns PayloadLayer if

    /// data is not valid.

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

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

    /// @param[in] prevLayer A pointer to the previous layer

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

    /// @return Layer* A newly allocated layer

    static Layer* parseSomeIpLayer(uint8_t* data, size_t dataLen, Layer* prevLayer, Packet* packet);

    /// Get a pointer to the basic SOME/IP header. Notice this points directly to the data, so every change will

    /// change the actual packet data

    /// @return A pointer to the someiphdr

    someiphdr* getSomeIpHeader() const

    {

      return reinterpret_cast<someiphdr*>(m_Data);

    }

    /// Checks if given port is a SOME/IP protocol port (only Service Discovery ports are checked for now)

    /// @param[in] port Port to check

    /// @return true if SOME/IP protocol port, false if not

    static bool isSomeIpPort(uint16_t port);

    /// Adds port to a list of ports where pcap checks for SOME/IP communication.

    /// Each port must be removed at the end in order to have no memory leak.

    /// @param[in] port Port to add

    static void addSomeIpPort(uint16_t port);

    /// Removes port from a list of ports where pcap checks for SOME/IP communication.

    /// @param[in] port Port to remove

    static void removeSomeIpPort(uint16_t port);

    /// Removes all ports from a list of ports where pcap checks for SOME/IP communication.

    static void removeAllSomeIpPorts();

    /// Get the messageID

    /// @return uint32_t returned in host endian

    uint32_t getMessageID() const;

    /// Set the Message ID

    /// @param[in] messageID messageID to set

    void setMessageID(uint32_t messageID);

    /// Get the serviceID

    /// @return uint16_t returned in host endian

    uint16_t getServiceID() const;

    /// Set the Service ID

    /// @param[in] serviceID serviceID to set

    void setServiceID(uint16_t serviceID);

    /// Get the methodID

    /// @return uint16_t returned in host endian

    uint16_t getMethodID() const;

    /// Set the Method ID

    /// @param[in] methodID methodID to set

    void setMethodID(uint16_t methodID);

    /// Get the Length Field of the SOME/IP header

    /// @return uint32_t The length field of the SOME/IP header

    uint32_t getLengthField() const;

    /// Get the requestID

    /// @return uint32_t returned in host endian

    uint32_t getRequestID() const;

    /// Set the Request ID

    /// @param[in] requestID requestID to set

    void setRequestID(uint32_t requestID);

    /// Get the sessionID

    /// @return uint16_t returned in host endian

    uint16_t getSessionID() const;

    /// Set the Session ID

    /// @param[in] sessionID sessionID to set

    void setSessionID(uint16_t sessionID);

    /// Get the clientID

    /// @return uint16_t returned in host endian

    uint16_t getClientID() const;

    /// Set the Client ID

    /// @param[in] clientID clientID to set

    void setClientID(uint16_t clientID);

    /// Get the protocolVersion

    /// @return uint8_t

    uint8_t getProtocolVersion() const;

    /// Set the Protocol Version

    /// @param[in] version version to set

    void setProtocolVersion(uint8_t version);

    /// Get the interfaceVersion

    /// @return uint8_t

    uint8_t getInterfaceVersion() const;

    /// Set the Interface Version

    /// @param[in] version version to set

    void setInterfaceVersion(uint8_t version);

    /// Get the message type

    /// @return uint8_t

    uint8_t getMessageTypeAsInt() const;

    /// Get the message type

    /// @return SomeIpLayer::MsgType

    SomeIpLayer::MsgType getMessageType() const;

    /// Set the Message Type

    /// @param[in] type Type to set

    void setMessageType(MsgType type);

    /// Set the Message Type

    /// @param[in] type Type to set

    void setMessageType(uint8_t type);

    /// Get the returnCode

    /// @return uint8_t

    uint8_t getReturnCode() const;

    /// Set the returnCode

    /// @param[in] returnCode ReturnCode to set

    void setReturnCode(uint8_t returnCode);

    /// Set the length field of the SOME/IP header

    /// @param[in] payloadLength Length of the payload

    void setPayloadLength(uint32_t payloadLength);

    /// @return A pointer for the layer payload, meaning the first byte after the header

    uint8_t* getPduPayload() const

    {

      return m_Data + getSomeIpHeaderLen();

    }

    /// @return The size in bytes of the payload

    size_t getPduPayloadSize() const

    {

      return getHeaderLen() - getSomeIpHeaderLen();

    }

    /// Get the Length of the SOME/IP header inc payload

    /// @return size_t

    size_t getHeaderLen() const override

    {

      return sizeof(uint32_t) * 2 + getLengthField();

    }

    /// Does nothing for this layer

    virtual void computeCalculateFields() override

    {}

    /// Identifies the following next layers: SomeIpLayer, SomeIpTpLayer, SomeIpSdLayer. Otherwise sets PayloadLayer

    void parseNextLayer() override;

    /// @return The string representation of the SOME/IP layer

    virtual std::string toString() const override;

    /// @return The OSI model layer of this layer

    OsiModelLayer getOsiModelLayer() const override

    {

      return OsiModelApplicationLayer;

    }

  protected:

    SomeIpLayer()

    {}

  private:

    static const uint8_t SOMEIP_PROTOCOL_VERSION = 1;

    virtual size_t getSomeIpHeaderLen() const

    {

      return sizeof(someiphdr);

    }

    // Using unordered_set since insertion and search should be almost constant time

    static std::unordered_set<uint16_t> m_SomeIpPorts;

  };

  /// @class SomeIpTpLayer

  /// Represents an SOME/IP Transport Protocol Layer

  class SomeIpTpLayer : public SomeIpLayer

  {

  public:

    /// @struct someiptphdr

    /// Represents an SOME/IP-TP protocol header.

#pragma pack(push, 1)

    struct someiptphdr : someiphdr

    {

      /// Contains the offset and the more segments flag. 28 bit offset field measured in 16 bytes + 3 bit

      /// reserved + 1 bit more segments flag

      uint32_t offsetAndFlag;

    };

#pragma pack(pop)

    static_assert(sizeof(someiptphdr) == 20, "someiptphdr size is not 20 bytes");

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

    /// @param[in] data A pointer to the raw data (will be casted to @ref someiptphdr)

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

    /// @param[in] prevLayer A pointer to the previous layer

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

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

        : SomeIpLayer(data, dataLen, prevLayer, packet)

    {}

    /// A constructor that creates empty layer and sets values

    /// @param[in] serviceID Service ID

    /// @param[in] methodID Method ID

    /// @param[in] clientID Client ID

    /// @param[in] sessionID Session ID

    /// @param[in] interfaceVersion Interface Version

    /// @param[in] type Type of the message

    /// @param[in] returnCode Return Code

    /// @param[in] offset Offset indicating the data offset in increments of 16 bytes

    /// @param[in] moreSegmentsFlag Flag indicating whether more SOME/IP-TP Packets will follow

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

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

    SomeIpTpLayer(uint16_t serviceID, uint16_t methodID, uint16_t clientID, uint16_t sessionID,

                  uint8_t interfaceVersion, MsgType type, uint8_t returnCode, uint32_t offset,

                  bool moreSegmentsFlag, const uint8_t* const data = nullptr, size_t dataLen = 0);

    /// Destroy the layer object

    ~SomeIpTpLayer() override = default;

    /// Get a pointer to the basic SOME/IP-TP header. Notice this points directly to the data, so every change will

    /// change the actual packet data

    /// @return A pointer to the @ref someiptphdr

    someiptphdr* getSomeIpTpHeader() const

    {

      return reinterpret_cast<someiptphdr*>(m_Data);

    }

    /// Get the Offset. Offset is returned in multiple of 16 bytes.

    /// @return The offset value

    uint32_t getOffset() const;

    /// Set the Offset. Already has to be in multiples of 16 bytes.

    /// If 32 bytes have already been transmitted, the offset has to be set to 2.

    /// @param[in] offset Offset to set. Already has to be in multiples of 16 bytes.

    void setOffset(uint32_t offset);

    /// Get the More Segments Flag

    /// @return true if the More Segments Flag is set, false if it is not set

    bool getMoreSegmentsFlag() const;

    /// Set the More Segments Flag

    /// @param[in] flag True if the More Segments Flag shall be set, false for resetting

    void setMoreSegmentsFlag(bool flag);

    /// Sets the message type in this layer with enabling the TP flag

    void computeCalculateFields() override;

    /// @return The string representation of the SOME/IP-TP layer

    std::string toString() const override;

  private:

    static const uint32_t SOMEIP_TP_MORE_FLAG_MASK = 0x01;

    static const uint32_t SOMEIP_TP_OFFSET_MASK = 0xFFFFFFF0;

    size_t getSomeIpHeaderLen() const override

    {

      return sizeof(someiptphdr);

    }

    static uint8_t setTpFlag(uint8_t messageType);

  };

}  // namespace pcpp