#include "psfp-flow-meter-instance.h"

#include "ns3/log.h"
#include "ns3/integer.h"
#include "ns3/uinteger.h"
#include "ns3/boolean.h"
#include "ns3/simulator.h"

#include "ns3/ethernet-header2.h"
#include "ns3/ethernet-trailer.h"

namespace ns3
{

NS_LOG_COMPONENT_DEFINE("FlowMeterInstance");

NS_OBJECT_ENSURE_REGISTERED(FlowMeterInstance);

TypeId
FlowMeterInstance::GetTypeId()
{
    static TypeId tid =
        TypeId("ns3::FlowMeterInstance")
            .SetParent<Object>()
            .SetGroupName("Tsn")
            .AddConstructor<FlowMeterInstance>()
            .AddAttribute("CIR",
                          "CIR parameter in bit/s",
                          DataRateValue(DataRate("0Gb/s")),
                          MakeDataRateAccessor(&FlowMeterInstance::m_cir),
                          MakeDataRateChecker())
            .AddAttribute("CBS",
                          "CBS parameter in bit",
                          UintegerValue(0),
                          MakeUintegerAccessor(&FlowMeterInstance::m_cbs),
                          MakeUintegerChecker<uint32_t>())
            .AddAttribute("EIR",
                          "EIR parameter in bit/s",
                          DataRateValue(DataRate("0Gb/s")),
                          MakeDataRateAccessor(&FlowMeterInstance::m_eir),
                          MakeDataRateChecker())
            .AddAttribute("EBS",
                          "EBS parameter in bit",
                          UintegerValue(0),
                          MakeUintegerAccessor(&FlowMeterInstance::m_ebs),
                          MakeUintegerChecker<uint32_t>())
            .AddAttribute("DropOnYellow",
                          "Drop on yellow function activation boolean",
                          BooleanValue(false),
                          MakeBooleanAccessor(&FlowMeterInstance::m_dropOnYellow),
                          MakeBooleanChecker())
            .AddAttribute("CF",
                          "coupling flag boolean",
                          BooleanValue(false),
                          MakeBooleanAccessor(&FlowMeterInstance::m_cf),
                          MakeBooleanChecker())
            .AddAttribute("MarkAllFramesRedEnable",
                          "MarkAllFramesRedEnable function activation boolean",
                          BooleanValue(false),
                          MakeBooleanAccessor(&FlowMeterInstance::m_markAllFramesRedEnable),
                          MakeBooleanChecker());
    return tid;
}

FlowMeterInstance::FlowMeterInstance()
{
  NS_LOG_FUNCTION(this);
  m_lastTokenUpdateTime = Simulator::Now();
  m_markAllFramesRed = false;
}

FlowMeterInstance::~FlowMeterInstance()
{
  NS_LOG_FUNCTION(this);
}

bool
FlowMeterInstance::Test(Ptr<Packet> packet)
{
  NS_LOG_FUNCTION(this);
  updateTokenBuckets();

  Ptr<Packet> payload = packet->Copy();
  EthernetHeader2 ethHeader;
  EthernetTrailer trailer;
  payload->RemoveHeader(ethHeader);
  payload->RemoveTrailer(trailer);

  if (m_markAllFramesRed){
    //Mark all frame = drop all
    NS_LOG_INFO("[PSFP] Packet #" << payload->GetUid() << " dropped due to markAllFrameRed");
    return true;
  }

  NS_LOG_INFO("pkt size = " << payload->GetSize());
  //First token bucket test
  if (payload->GetSize() <= m_committedToken) {
    //Mark green
    m_committedToken -= payload->GetSize();
    NS_LOG_INFO("[PSFP] Packet #" << payload->GetUid() << " marked green");
    return false;
  }

  //Second token bucket test
  if (payload->GetSize() <= m_excessToken) {
    //Mark yellow
    m_excessToken -= payload->GetSize();
    if(m_dropOnYellow){
      NS_LOG_INFO("[PSFP] Packet #" << payload->GetUid() << " marked yellow and dropped");
      return true;
    }
    else{
      NS_LOG_INFO("[PSFP] Packet #" << payload->GetUid() << " marked yellow and passed");
      return false;
    }
  }
  else{
    //Mark red
    NS_LOG_INFO("[PSFP] Packet #" << payload->GetUid() << " marked red (committedToken=" << m_committedToken  << ", need " << payload->GetSize() << " tokens to pass)");
    if(m_markAllFramesRedEnable){
      m_markAllFramesRed = true;
    }
    return true;
  }


}

void
FlowMeterInstance::updateTokenBuckets()
{
  NS_LOG_FUNCTION(this);
  uint16_t tokenOverflow = 0;
  Time sinceLastUpdate = Simulator::Now() - m_lastTokenUpdateTime;

  m_committedToken = m_committedToken + (sinceLastUpdate.GetSeconds() * m_cir.GetBitRate())/8.;
  if (m_committedToken > m_cbs){
    if (m_cf){
      tokenOverflow = m_committedToken - m_cbs;
    }
    m_committedToken = m_cbs;
  }

  m_excessToken = m_excessToken + (sinceLastUpdate.GetSeconds() * m_eir.GetBitRate())/8. + tokenOverflow;
  if (m_excessToken>m_ebs){
    m_excessToken = m_ebs;
  }

  m_lastTokenUpdateTime = Simulator::Now();
  NS_LOG_INFO("m_committedToken = " << m_committedToken);
  NS_LOG_INFO("m_excessToken =    " << m_excessToken);
}



};