#ifndef GPTP_H
#define GPTP_H

#include "ns3/application.h"

#include "ns3/clock.h"
#include "ns3/tsn-net-device.h"
#include "ns3/gPTP-header.h"


#define NANOINSECOND 1000000000

namespace ns3
{


class GPTP : public Application
{
  public:
    /**
     * \brief Get the type ID.
     * \return the object TypeId
     */
    static TypeId GetTypeId();

    GPTP();

    ~GPTP() override;


    /**
     * Enumeration of the states of the PTP port.
     */
    enum GPTPportState
    {
        MASTER,
        SLAVE,
        PASSIVE,
    };

    void SetMainClock(Ptr<Clock> c);
    void AddDomain(uint8_t domainId);
    void AddDomain(uint8_t domainId, Ptr<Clock> clock);
    void AddPort(Ptr<TsnNetDevice> net, GPTPportState state, uint8_t domainId);



  protected:
    void DoDispose() override;


    TracedCallback<Ptr<TsnNetDevice>,
                  double> m_NrTrace;
    TracedCallback<Ptr<TsnNetDevice>,
                  double> m_PdelayTrace;
    TracedCallback<Time> m_OffsetTrace;
    TracedCallback<Time> m_ClockBeforeCorrectionTrace;
    TracedCallback<Time> m_ClockAfterCorrectionTrace;

  private:

    struct syncPtrStruc
    {
      uint64_t correctionField = 0;
      uint64_t sourceClockIndentity = 0;
      uint16_t sourcePortIndentity = 0;
      uint16_t sequenceId = 0;
      uint64_t preciseOriginTimestampSecond = 0;
      uint32_t preciseOriginTimestampNanoSecond = 0;
      uint64_t syncOriginTimestampSecond = 0;
      uint32_t syncOriginTimestampNanoSecond = 0;
      uint64_t pktUid = 0;
      bool pktSent = false;
      uint64_t syncReceiptTimestampSecond = 0;
      uint32_t syncReceiptTimestampNanoSecond = 0;
      uint32_t cumulativeScaledRateOffset = 0;
    };

    struct pdelayReqPtrStruc
    {
      uint64_t correctionField = 0;
      uint64_t sourceClockIndentity = 0;
      uint16_t sourcePortIndentity = 0;
      uint16_t sequenceId = 0;
      uint64_t requestOriginTimestampSecond = 0;
      uint32_t requestOriginTimestampNanoSecond = 0;
      uint64_t pktUid = 0;
      bool pktSent = false;
    };

    struct pdelayRespStruc
    {
      uint64_t correctionField = 0;
      uint64_t sourceClockIndentity = 0;
      uint16_t sourcePortIndentity = 0;
      uint16_t sequenceId = 0;
      uint64_t requestReceiptTimestampSecond = 0;
      uint32_t requestReceiptTimestampNanoSecond = 0;
      uint64_t requestingClockIdentity = 0;
      uint16_t requestingPortIdentity = 0;
      uint64_t responseReceiptTimestampSecond = 0;
      uint32_t responseReceiptTimestampNanoSecond = 0;
      uint64_t pktUid = 0;
      bool pktSent = false;
    };

    struct pdelayRespFollowUpStruc
    {
      uint64_t correctionField = 0;
      uint64_t sourceClockIndentity = 0;
      uint16_t sourcePortIndentity = 0;
      uint16_t sequenceId = 0;
      uint64_t responseOriginTimestampSecond = 0;
      uint32_t responseOriginTimestampNanoSecond = 0;
      uint64_t requestingClockIdentity = 0;
      uint16_t requestingPortIdentity = 0;
    };

    struct GPTPPortPerDomainStruc
    {
      uint8_t domainId;
      GPTPportState state;
      syncPtrStruc syncPtr;
    };

    /**
     * \ingroup tsn
     * Structure holding port, there states and the PTPinstance datas.
     */
    struct GPTPPort
    {
        Ptr<TsnNetDevice> net;

        std::vector<GPTPPortPerDomainStruc> domains = {};

        bool rcvdPdelayResp = false;                                            //STD 802.1AS-2020 : 11.2.19.2.2
        pdelayRespStruc rcvdPdelayRespPtr;                                  //STD 802.1AS-2020 : 11.2.19.2.3
        bool rcvdPdelayRespFollowUp = false;                                    //STD 802.1AS-2020 : 11.2.19.2.4
        pdelayRespFollowUpStruc rcvdPdelayRespFollowUpPtr;                  //STD 802.1AS-2020 : 11.2.19.2.5
        pdelayReqPtrStruc txPdelayReqPtr;                                     //STD 802.1AS-2020 : 11.2.19.2.6
        uint16_t lostResponses;                                                 //STD 802.1AS-2020 : 11.2.19.2.9
        bool neighborRateRatioValid = false;                                    //STD 802.1AS-2020 : 11.2.19.2.10

        pdelayRespStruc txPdelayRespPtr;
        Time t3_prime = Time(0);
        Time t4_prime = Time(0);
        double neighborRateRatio = 1;
        double meanLinkDelay = 0;
        bool asCapableAcrossDomains = false;
    };

    struct domainStruc
    {
      uint8_t domainId;
      Ptr<Clock> clock;
    };

    void StartApplication() override;
    void StopApplication() override;
    void StartPdelayMechanism();
    void StartSyncDistributionMechanism(uint8_t domainId);

    bool RXCallback(Ptr<TsnNetDevice> dev, Ptr<const Packet> pkt, uint16_t mode, const Address& sender, Time rxTimestamp);
    bool TXCallback(Ptr<const Packet> pkt, Time txTimestamp);

    void SendSync(uint8_t domainId);
    void SendFollowUp(GPTPPort port, uint16_t portId, uint8_t id);
    void SendPdelayRequest(GPTPPort port, uint16_t portId);
    void SendPdelayResp(Ptr<TsnNetDevice> dev, GptpHeader rxHeader, Time rxTimestamp);
    void SendPdelayRespFup(Ptr<TsnNetDevice> dev, Time txTimestamp);

    void handleSync(Ptr<TsnNetDevice> dev, GptpHeader header, Ptr<Packet> pkt, Time rxTimestamp);
    void handleFollowUp(Ptr<TsnNetDevice> dev, GptpHeader header, Ptr<Packet> pkt, Time rxTimestamp);
    void handlePdelayResp(Ptr<TsnNetDevice> dev, GptpHeader header, Ptr<Packet> pkt, Time rxTimestamp);
    void handlePdelayRespFup(Ptr<TsnNetDevice> dev, GptpHeader header, Ptr<Packet> pkt);

    void ResetPdelay(uint16_t portId);
    double computePdelayRateRatio(uint16_t portId);      //STD 802.1AS-2020 : 11.2.19.3.2
    double computePropTime(uint16_t portId);             //STD 802.1AS-2020 : 11.2.19.3.3
    Time computeOffset(uint16_t portId, uint16_t id, double r);

    uint16_t GetPortIdFromNetDev(Ptr<TsnNetDevice> dev);
    int GetDomainKeyFromNetDev(Ptr<TsnNetDevice> dev, uint16_t portId, uint8_t domainId);
    Ptr<Clock> getClockFromDomainId(uint8_t domainId);
    bool IsGm(uint8_t domainId);
    void readPledayPayload(uint8_t* payload, uint64_t& timestampSecond, uint32_t& timestampNanoSecond, uint64_t& clockIdentity, uint16_t& portIdentity);
    void readFollowUpPayload(uint8_t* payload,  uint64_t& timestampSecond,  uint32_t& timestampNanoSecond,  uint32_t& cumulativeScaledRateOffset);

    uint16_t m_pdelaySequenceId = 0;
    double m_meanLinkDelayThresh = 800;

    Ptr<Clock> m_mainClock = nullptr;
    uint64_t m_baseClockIndentity;
    Time m_pdelayInterval;
    Time m_syncInterval;
    uint8_t m_priority;
    std::vector<domainStruc> m_domains = {};

    const Mac48Address GPTP_MULTICASTMAC = Mac48Address("01:80:C2:00:00:0E");
    static const uint16_t GPTP_ETHERTYPE = 0x88F7;
    static const uint8_t MESSAGETYPE_SYNC = 0; //STD 802.1AS-2020 : Table 11-5
    static const uint8_t MESSAGETYPE_PDELAYREQ = 2; //STD 802.1AS-2020 : Table 11-5
    static const uint8_t MESSAGETYPE_PDELAYRESP = 3; //STD 802.1AS-2020 : Table 11-5
    static const uint8_t MESSAGETYPE_FOLLOWUP = 8; //STD 802.1AS-2020 : Table 11-5
    static const uint8_t MESSAGETYPE_PDELAYRESPFOLLOWUP = 10; //STD 802.1AS-2020 : Table 11-5

    EventId m_pdelayReqTxEvent;
    EventId m_syncTxEvent;

    std::vector<GPTPPort> m_ports;

    Time m_pktProcessingTime = Time(MicroSeconds(20));
    Time m_TimestampProcessingTime = Time(MicroSeconds(20));

};

} // namespace ns3

#endif /* GPTP_H */