// -------------------------------------------------------------------------
// -----                PndSdsStripClusterTask source file             -----
// -------------------------------------------------------------------------

#include <cmath>

#include "TClonesArray.h"
#include "TArrayD.h"
#include "TGeoManager.h"
#include "TGeoMatrix.h"
#include "TCanvas.h"
#include "TMatrixD.h"
#include "FairRootManager.h"
#include "FairRun.h"
#include "FairRuntimeDb.h"
#include "FairGeoNode.h"
#include "FairGeoVector.h"
#include "FairContFact.h" 

#include "PndStringSeparator.h"
#include "PndSdsStripDigiPar.h"
#include "PndSdsStripClusterTask.h"
#include "PndSdsMCPoint.h"
#include "PndSdsCalcStrip.h"
#include "PndSdsDigiStrip.h"
#include "PndSdsClusterStrip.h"
#include "PndGeoHandling.h"

#include "PndSdsSimpleStripClusterFinder.h"
#include "PndSdsStripAdvClusterFinder.h"
#include "PndSdsChargeWeightingAlgorithms.h"
#include <map>

// -----   Default constructor   -------------------------------------------
PndSdsStripClusterTask::PndSdsStripClusterTask() :
PndSdsTask("SDS Strip Clustertisation Task")
{
  fChargeCut = 1.e8; // this reset dynamically
  fDigiParameterList = new TList();
  fChargeDigiParameterList = new TList();
  fPersistance = kTRUE;
  fGeoH = PndGeoHandling::Instance();
  fChargeAlgos=0;
  fCurrentDigiPar=0;
  fCurrentChargeConverter=0;
  fCurrentStripCalcTop=0;
  fCurrentStripCalcBot=0;
  fCurrentClusterfinder=0;
}

// -----   Named constructor   -------------------------------------------
PndSdsStripClusterTask::PndSdsStripClusterTask(const char* name) :
PndSdsTask(name)
{
  // TODO: fChargeCut in parameter database??
  fChargeCut = 1.e8; // this ist really large and shall have no effect
  fDigiParameterList = new TList();
  fChargeDigiParameterList = new TList();
  fPersistance = kTRUE;
  fGeoH = PndGeoHandling::Instance();
  fChargeAlgos=0;
  fCurrentChargeConverter=0;
  fCurrentDigiPar=0;
  fCurrentStripCalcTop=0;
  fCurrentStripCalcBot=0;
  fCurrentClusterfinder=0;
}

// -----   Destructor   ----------------------------------------------------
PndSdsStripClusterTask::~PndSdsStripClusterTask()
{
	if(0!=fDigiParameterList) delete fDigiParameterList;
  if(0!=fChargeDigiParameterList) delete fChargeDigiParameterList;
  ClearCalculators();
}
// -------------------------------------------------------------------------

void PndSdsStripClusterTask::ClearCalculators()
{
	for( std::map<const char*,PndSdsCalcStrip*>::iterator it = fStripCalcTop.begin(); it != fStripCalcTop.end(); it++){
		if(0 != it->second) delete it->second;
		it->second = 0;
	}
	for( std::map<const char*,PndSdsCalcStrip*>::iterator it = fStripCalcBot.begin(); it != fStripCalcBot.end(); it++){
		if(0 != it->second) delete it->second;
		it->second = 0;
	}
  if(0 != fChargeAlgos) delete fChargeAlgos;
	for(std::map<const char*,PndSdsChargeConversion*>::iterator it = fChargeConverter.begin(); it != fChargeConverter.end(); it++){
		if(0 != it->second) delete it->second;
		it->second = 0;
	}  
	for(std::map<const char*,PndSdsStripClusterer*>::iterator it = fClusterFinderList.begin(); it != fClusterFinderList.end(); it++){
		if(0 != it->second) delete it->second;
		it->second = 0;
	}  
  
  fCurrentChargeConverter=0;
  fCurrentStripCalcTop=0;
  fCurrentStripCalcBot=0;
  fCurrentClusterfinder=0;  
}

// -------------------------------------------------------------------------

void PndSdsStripClusterTask::SetParContainers()
{
	return;
}

//
InitStatus PndSdsStripClusterTask::ReInit()
{  
  InitStatus stat=kERROR;
  ClearCalculators();
  SetParContainers(); 
  SetCalculators(); 
  stat=kSUCCESS; 
  return stat;
}

void PndSdsStripClusterTask::SetCalculators() 
{ 
  // called at the enf of Init() 
  // TODO: Implement more clusterfinders
  if (fVerbose>1) Info("SetCalculators","sds part");
  ClearCalculators();
  TIter params(fDigiParameterList); 
  while(PndSdsStripDigiPar* digipar=(PndSdsStripDigiPar*)params()){ 
    if(0==digipar) { 
      Error("SetCalculators()","A Digi Parameter Set does not exist properly."); 
      continue; 
    } 
    const char* senstype = digipar->GetSensType(); 
    if(fVerbose>1){ 
      Info("SetCalculators()","Create a Parameter Set for %s sensors",senstype); 
      std::cout<<senstype<<"#"<<std::endl; 
      digipar->Print(); 
    } 
    fStripCalcTop[senstype]=new PndSdsCalcStrip(digipar,kTOP); 
    fStripCalcTop[senstype]->SetVerboseLevel(fVerbose); 
    fStripCalcBot[senstype]=new PndSdsCalcStrip(digipar,kBOTTOM); 
    fStripCalcBot[senstype]->SetVerboseLevel(fVerbose);  
  } 
  fChargeAlgos = new PndSdsChargeWeightingAlgorithms(fDigiArray);
  fChargeAlgos->SetVerbose(fVerbose);
} 

// -----   Public method Init   --------------------------------------------
InitStatus PndSdsStripClusterTask::Init()
{
  
  SetBranchNames();
  
  FairRootManager* ioman = FairRootManager::Instance();
  if ( ! ioman )
  {
    std::cout << "-E- PndSdsStripClusterTask::Init: "
    << "RootManager not instantiated!" << std::endl;
    return kFATAL;
  }
  
  // Get input array
  fDigiArray = (TClonesArray*) ioman->GetObject(fInBranchName);
  if ( ! fDigiArray )
  {
    std::cout << "-W- PndSdsStripClusterTask::Init: "
    << "No SDSDigi array!" << std::endl;
    return kERROR;
  }
  
  // set output arrays
  
  fClusterArray = new TClonesArray("PndSdsClusterStrip");
  ioman->Register(fClustBranchName, fFolderName, fClusterArray, fPersistance);
  
  fHitArray = new TClonesArray("PndSdsHit");
  ioman->Register(fOutBranchName, fFolderName, fHitArray, fPersistance);
  
  SetInBranchId();
  
  SetCalculators();
  
  Info("Init","Initialisation successfull");
  return kSUCCESS;
}
// -------------------------------------------------------------------------

// -----   Public method Exec   --------------------------------------------
void PndSdsStripClusterTask::Exec(Option_t* opt)
{
  if (fVerbose > 2)
    std::cout<<" **Starting PndSdsStripClusterTask::Exec()**"<<std::endl;
  std::vector<PndSdsDigiStrip> digiStripArray;
  // Reset output array
  if ( ! fClusterArray ) Fatal("Exec", "No ClusterArray");
  fClusterArray->Delete();
  if ( ! fHitArray ) Fatal("Exec", "No HitArray");
  fHitArray->Delete();
  // when we have no digis, we can end the event here.
  if (fDigiArray->GetEntriesFast() == 0) return;
  fGeoH->SetVerbose(fVerbose);
  
  // Setup
  FillClusterFinders();
  
  std::vector< PndSdsClusterStrip* > clusters;
  std::vector< Int_t > topclusters;// contains index to fClusterArray
  std::vector< Int_t > botclusters;// contains index to fClusterArray
  std::vector< Int_t > oneclustertop;
  std::vector< Int_t > oneclusterbot;
  std::vector< Int_t > leftDigis;
  Int_t mcindex, clindex, botIndex, topIndex;
  Int_t detID = FairRootManager::Instance()->GetBranchId(fInBranchName);
  Int_t clDetID = FairRootManager::Instance()->GetBranchId(fClustBranchName);
  Double_t mycharge;
  TVector2 meantopPoint, meanbotPoint, onsensorPoint;
  TVector3 hitPos,hitErr;
  TMatrixD hitCov(3,3);
  Int_t clusterOffset = 0;
  PndSdsHit* tmphit;
  
  // -------   SEARCH  ------
  TIter parsetiter(fDigiParameterList);
  while ( PndSdsStripDigiPar* digipar = (PndSdsStripDigiPar*)parsetiter() )
  { // loop over all parameter sets and their filled finders (representing sensor types)
    SetCurrentCalculators(digipar);
    
    clusters = fCurrentClusterfinder->SearchClusters();
    // fetch ids in 'clusters' to the top and bot side
    topclusters = fCurrentClusterfinder->GetTopClusterIDs();
    botclusters = fCurrentClusterfinder->GetBotClusterIDs();
    if(fVerbose > 2) {
      leftDigis = fCurrentClusterfinder->GetLeftDigiIDs();
      if (0<leftDigis.size()){
        std::cout << "There are "<<leftDigis.size()<<" Digis not assigned to"
        << " clusters:\n";
        for(unsigned int s=0;s<leftDigis.size();s++)
        {
          std::cout<<leftDigis[s]<<"|";
        }
        std::cout<<std::endl;
      } else std::cout<<"All Digis assigned to clusters"<<std::endl;
    }
    // Fill the ClonesArray for output TODO: do this better, don't copy objects around
    // save array size before we fill
    clusterOffset = fClusterArray->GetEntriesFast();
    for(std::vector< PndSdsClusterStrip* >::iterator clit= clusters.begin();
        clit!=clusters.end(); ++clit)
    {
      clindex = fClusterArray->GetEntriesFast();
      PndSdsClusterStrip* myCluster = new((*fClusterArray)[clindex]) PndSdsClusterStrip(*(*clit));
      for(int i = 0; i < myCluster->GetClusterSize(); i++){
    	  myCluster->AddLink(FairLink(fInBranchName, myCluster->GetDigiIndex(i)));
      }
    }
    
    //printout for checking
    if(fVerbose > 2) {
      std::cout<<"Check.. Offset: "<<clusterOffset<<"Top Clusters: ";
      for (std::vector< Int_t>::iterator itTop = topclusters.begin();
           itTop!=topclusters.end(); ++itTop) 
      {
        std::cout<<*itTop<<" | ";
      }
      std::cout<<std::endl;
      std::cout<<"Bot Clusters: ";
      for (std::vector< Int_t>::iterator itBot = botclusters.begin();
           itBot!=botclusters.end(); ++itBot) 
      {
        std::cout<<*itBot<<" | ";  
      }
      std::cout<<std::endl;
    }
    
    // begin the hit reconstruction
    // loop structure:
    //
    //top clusters
    // |-calculate chargeweighted mean
    // |-bot clusters
    // |-|-calc chargew. mean
    // |-|-calc the crossing strip points
    // |-|-fill hit array
    
    // -----  merge top/bot clusters to hits  -----
    // loop on clusters from the top side
    for (std::vector< Int_t>::iterator itTop = topclusters.begin();
         itTop!=topclusters.end(); ++itTop)
    {
      topIndex= *itTop + clusterOffset; // index in fClusterArray
      Double_t topcharge = 0., meantopstrip=0.,meantoperr=0. ;
      PndSdsClusterStrip* aTopCluster=clusters[*itTop];
      oneclustertop = aTopCluster->GetClusterList();
      if(oneclustertop.size()<1) continue;
      PndSdsDigiStrip* atopDigi = ((PndSdsDigiStrip*)fDigiArray->At(oneclustertop[0]));
      Int_t sensorIDtop = atopDigi->GetSensorID();
      
      //if (kFALSE==SelectSensorParams(detName)) continue; // Invalid parameters, skip here.       
      CalcMeanCharge(aTopCluster,meantopstrip,meantoperr,topcharge);
      
      if(oneclustertop.size()==1 && topcharge < fSingleStripChargeThreshold) { 
        std::cout<<"-W- PndSdsClusterTask::Exec: Single strip charge falls below the threshold of "<<fSingleStripChargeThreshold<<"e- : skipping. "<<endl; 
        continue; 
      }
      if(topcharge <= 0) { // not a sane charge
        Error("Exec() - Hit combination","Not a sane top charge (%f) calculated, skip cluster %i",topcharge, *itTop);
        continue;
      }
      if(meantopstrip < 0) { // not a sane strip number
        Error("Exec() - Hit combination","Not a sane top mean (%f) calculated, skip cluster %i",meantopstrip, *itTop);
        continue;
      }
      fCurrentStripCalcTop->CalcStripPointOnLine(meantopstrip, meantopPoint);
      // loop on bottom side
      for (std::vector< Int_t>::iterator itBot = botclusters.begin();
           itBot!=botclusters.end(); ++itBot)
      {
        botIndex = *itBot + clusterOffset; // index in fClusterArray
        Double_t botcharge = 0., meanbotstrip=0., meanboterr=0.;
        PndSdsClusterStrip* aBotCluster = clusters[*itBot];
        oneclusterbot = aBotCluster->GetClusterList();
        if(oneclusterbot.size()<1)continue;
        PndSdsDigiStrip* abotDigi = ((PndSdsDigiStrip*)fDigiArray->At(oneclusterbot[0]));
        Int_t sensorIDbot = abotDigi->GetSensorID();
        
        //go to the next cluster if we didn't hit the same sensor
        if(sensorIDbot != sensorIDtop) continue;
        
        CalcMeanCharge(aBotCluster,meanbotstrip,meanboterr,botcharge);
        
        if(oneclusterbot.size() == 1 && botcharge < fSingleStripChargeThreshold) { 
          std::cout<<"-W- PndSdsClusterTask::Exec: Single strip charge falls below the threshold of "<<fSingleStripChargeThreshold<<"e- : skipping. "<<endl; 
          continue; 
        }
        if(botcharge <= 0) { // not a sane charge
          Error("Exec() - Hit combination","Not a sane bot charge (%f) calculated, skip cluster %i",botcharge, *itBot);
          continue;
        }
        if(meanbotstrip < 0) { // not a sane strip number
          Error("Exec() - Hit combination","Not a sane bot mean (%f) calculated, skip cluster %i",meanbotstrip, *itBot);
          continue;
        }
        
        if(fVerbose > 2)  {
          std::cout<<"Charges: Ctop = "<<topcharge<<" | Cbot = "<<botcharge
          <<" | difference bot-top = "<<botcharge-topcharge
          <<" | Cut at "<<fChargeCut<<std::endl;
        }
        
        if(fChargeCut>0 && fabs(botcharge-topcharge)<fChargeCut)
        {// look if the charges are not too differently
          mycharge = (botcharge + topcharge) / 2.;
          fCurrentStripCalcBot->CalcStripPointOnLine(meanbotstrip, meanbotPoint);
          mcindex=-1; // reset
          for(Int_t mcI = 0; mcI<atopDigi->GetNIndices();mcI++){ 
            if (atopDigi->GetIndex(mcI) > -1) {
              for(Int_t mcIb = 0; mcIb<abotDigi->GetNIndices();mcIb++){ 
                if (abotDigi->GetIndex(mcIb) == atopDigi->GetIndex(mcI)) {
                  mcindex = abotDigi->GetIndex(mcIb);
                  break;
                }
              }
            }
          }
          Bool_t test = Backmap(meantopPoint, meantoperr, meanbotPoint, meanboterr, hitPos, hitCov,sensorIDtop);
          if (kFALSE==test) continue;
          
          // --- add hit to list ---
          Int_t i = fHitArray->GetEntriesFast();
          hitErr.SetXYZ(sqrt(hitCov[0][0]),sqrt(hitCov[1][1]),sqrt(hitCov[2][2]));
          tmphit = new((*fHitArray)[i]) PndSdsHit(clDetID,sensorIDtop,hitPos,hitErr,
                                                  topIndex,mycharge,oneclusterbot.size()+oneclustertop.size(),mcindex);
          tmphit->SetBotIndex(botIndex);
          tmphit->SetLink(FairLink(fClusterType, topIndex));
          tmphit->AddLink(FairLink(fClusterType, botIndex));
          tmphit->SetCov(hitCov);
          if (fVerbose > 1) tmphit->Print();
        } else
          if (fVerbose > 2) std::cout<<"Strip charge contents too differently"<<std::endl;
      }// loop bot clusters
    }// loop top clusters
  }//loop finders
  
  if (fVerbose > 1)
    std::cout << "-I- PndSdsStripClusterTask: " << fClusterArray->GetEntriesFast()
    << " Mvd Clusters and " << fHitArray->GetEntriesFast()<<" Hits calculated."
    << " out of " <<fDigiArray->GetEntriesFast()<< " Digis"<< std::endl;
  return;
}

// ------------------------------------------------------------------------- 
Bool_t PndSdsStripClusterTask::SelectSensorParams(Int_t sensorID)
{
  TString detpath = fGeoH->GetPath(sensorID);
  if( !(detpath.Contains("Strip")) ) 
    return kFALSE; 
  TIter parsetiter(fDigiParameterList);
  while ( PndSdsStripDigiPar* digipar = (PndSdsStripDigiPar*)parsetiter() )  
  { 
    const char* sensortype = digipar->GetSensType();
    if(detpath.Contains(sensortype))  {
      SetCurrentCalculators(digipar);
      return kTRUE; 
    } 
  } 
  // no suiting object found 
  if (fVerbose > 1) std::cout<<"detector name does not contain a valid parameter name."<<std::endl; 
  if (fVerbose > 2) std::cout<<" DetName : "<<detpath<<std::endl; 
  return kFALSE; 
} 
// ------------------------------------------------------------------------- 

void PndSdsStripClusterTask::SetCurrentCalculators(PndSdsStripDigiPar* digipar)
{
  const char* sensortype = digipar->GetSensType();
  fCurrentStripCalcTop = fStripCalcTop[sensortype];
  fCurrentStripCalcBot = fStripCalcBot[sensortype];
  fCurrentClusterfinder = fClusterFinderList[sensortype];
  fCurrentChargeConverter = fChargeConverter[sensortype];
  fCurrentDigiPar = digipar;
  fChargeAlgos->SetCalcStrip(fCurrentStripCalcTop);
  fChargeAlgos->SetChargeConverter(fCurrentChargeConverter);
  fChargeCut = digipar->GetChargeCut();
  fSingleStripChargeThreshold = digipar->GetSingleChargeCut();
  return;
}

// ------------------------------------------------------------------------- 
void PndSdsStripClusterTask::ResetClusterFinders() 
{ 
  //recursively clean the digis in the clusterfinder objects each event 
  for(std::map<const char*,PndSdsStripClusterer*>::iterator CFiter = fClusterFinderList.begin(); 
      CFiter != fClusterFinderList.end(); CFiter++) 
  { 
    (CFiter->second)->Reinit(); 
  } 
} 
// ------------------------------------------------------------------------- 
void PndSdsStripClusterTask::FillClusterFinders()
{
  // Info("FillClusterFinders","Here! fCurrntClusterfinder:%p",fCurrentClusterfinder);
  ResetClusterFinders();
  // a std::map is a SORTED container, it is sorted by the identifier
  Int_t sensorID;
  Int_t strip;
  SensorSide side;
  PndSdsDigiStrip* myDigi=0;
  Bool_t tester=kFALSE;
  // Sort Digi indice into the clusterfinder
  if (fDigiArray->GetEntriesFast() == 0) return;
  if(fVerbose>2) Info("FillClusterFinders","adding these digis to the finders:"); 
  for (Int_t iDigi = 0; iDigi < fDigiArray->GetEntriesFast(); iDigi++)
  { // sort digis by sensor name and stripnumber
    myDigi = (PndSdsDigiStrip*)(fDigiArray->At(iDigi));
    if(fVerbose>2) {std::cout<<"Digi "<<iDigi<<" "; myDigi->Print();}
    sensorID = myDigi->GetSensorID();
    tester=SelectSensorParams(sensorID);
    if (kFALSE==tester) continue; // Invalid parameters, skip here.
    //we use the top side as "first" side
    fCurrentStripCalcTop->CalcFeChToStrip(myDigi->GetFE(), myDigi->GetChannel(), strip, side); 
    fCurrentClusterfinder->AddDigi(sensorID,side,myDigi->GetTimeStamp(),strip,iDigi);
  } 
  // make sure the digi array is distributed well
  fChargeAlgos->SetDigiArray(fDigiArray);
}

// ------------------------------------------------------------------------- 
TVector2 PndSdsStripClusterTask::CalcLineCross(
                                               TVector2 point1, TVector2 dir1,
                                               TVector2 point2, TVector2 dir2) const
{
  Double_t dx, dy, s, M, x, y;
  dx = point2.X() - point1.X();
  dy = point2.Y() - point1.Y();
  
  M  = dir1.X()*dir2.Y() - dir1.Y()*dir2.X();
  
  if(M !=0.)
  {
    s  = dir1.Y()*dx/M - dir1.X()*dy/M;
    x  = point2.X() + dir2.X()*s;
    y  = point2.Y() + dir2.Y()*s;
  }
  else
  {
    std::cout<<"Warning in PndSdsStripClusterTask::CalcLineCross(): M=0 setting (x,y) to 0"<<std::endl;
    x=0.;y=0.;
  }
  
  TVector2 result(x,y);
  return result;
}

void PndSdsStripClusterTask::Finish()
{
}

void PndSdsStripClusterTask::CalcMeanCharge(PndSdsClusterStrip* onecluster, Double_t &meanstrip, Double_t &meanerr, Double_t &charge)
{
  meanstrip=0;
  meanerr=0;
  charge=0;
	if (fCurrentDigiPar->GetClusterMean() == 0)
	{
    // Calculate mean position in position channels weighted by the charges
    Int_t strip;
    SensorSide side;
    Double_t tempcharge;
    std::vector<Int_t> oneclusterlist = onecluster->GetClusterList();
    for (std::vector<Int_t>::iterator itDigi = oneclusterlist.begin();
         itDigi != oneclusterlist.end(); ++itDigi)
    { // calculate the mean charge and stripnumber
      PndSdsDigiStrip* myDigi = (PndSdsDigiStrip*)fDigiArray->At(*itDigi);
      fCurrentStripCalcTop->CalcFeChToStrip(myDigi->GetFE(), myDigi->GetChannel(), strip, side);
      tempcharge = fCurrentChargeConverter->DigiValueToCharge(*myDigi);
      charge += tempcharge;
      meanstrip += tempcharge * strip;
      meanerr += tempcharge*tempcharge; // this is stupid, to be removed one day
    }
    meanstrip = meanstrip/charge;
    // this error treatment is: dx = dpitch * sqrt(weigthsquares)
    meanerr = sqrt(meanerr/(charge*charge));
    return;
	} else {
    //	//TODO: Apply other clusterfinder mean & error algorithms
		if(fVerbose>1)std::cout<<"-W- PndSdsStripClusterTask::CalcMeanCharge: Using a preliminary Chargeweighting, please set cluster_mod to 0 in your param file ."<<std::endl;
    //    if(onecluster->GetSensorSide()==kTOP) fCurrentChargeAlgos->SetCalcStrip(fCurrentStripCalcTop);
    //    else fCurrentChargeAlgos->SetCalcStrip(fCurrentStripCalcBot);
    //    fChargeAlgos->SetChargeConverter(fCurrentChargeConverter); // done somewhere else
    std::pair<Double_t,Double_t> result = fChargeAlgos->CenterOfGravity(onecluster);
    meanstrip=result.first;
    meanerr=result.second;
    std::vector<Int_t> oneclusterlist = onecluster->GetClusterList();
    for (std::vector<Int_t>::iterator itDigi = oneclusterlist.begin();
         itDigi != oneclusterlist.end(); ++itDigi)
    { 
      PndSdsDigiStrip* myDigi = (PndSdsDigiStrip*)fDigiArray->At(*itDigi);
      charge += fCurrentChargeConverter->DigiValueToCharge(*myDigi);
    }
    return;
	}
  return;
  
}



Bool_t PndSdsStripClusterTask::Backmap( TVector2 meantopPoint, Double_t meantoperr, TVector2 meanbotPoint, Double_t meanboterr,
                                       TVector3 &hitPos, TMatrixD &hitCov, Int_t &sensorID)
{
  // BACKMAPPING
  // get the backmapped point
  
  TVector3 localpos;
  TMatrixD locCov(3,3);
  Double_t t, b;
  
  Double_t errZ = 2.*fGeoH->GetSensorDimensionsShortId(sensorID).Z()/TMath::Sqrt(12.0);
  
  TVector2 onsensorPoint = 
  CalcLineCross(meantopPoint, fCurrentStripCalcTop->GetStripDirection(), meanbotPoint, fCurrentStripCalcBot->GetStripDirection() );
  // here we assume the sensor system to be in the _Middle_ of the volume
  localpos.SetXYZ( onsensorPoint.X(), onsensorPoint.Y(), 0.);
  
  // let's see if we're still on the sensor (cut combinations with noise off)
  if(fabs(localpos.X()) > fabs(fCurrentDigiPar->GetTopAnchor().X())) return kFALSE;
  if(fabs(localpos.Y()) > fabs(fCurrentDigiPar->GetTopAnchor().Y())) return kFALSE;
  
  //do the transformation from sensor to lab frame
  hitPos = fGeoH->LocalToMasterShortId(localpos,sensorID);
  
  // calculate the errors corresponding to a skewed system,
  // directions orthogonal to strip orientation
  t = meantoperr*fCurrentDigiPar->GetTopPitch()*sin(fCurrentDigiPar->GetOrient());
  b = meanboterr*fCurrentDigiPar->GetBotPitch()*sin(fCurrentDigiPar->GetOrient()+fCurrentDigiPar->GetSkew());
  locCov[0][0]=t*t+b*b;
  t = meantoperr*fCurrentDigiPar->GetTopPitch()*cos(fCurrentDigiPar->GetOrient());
  b = meanboterr*fCurrentDigiPar->GetBotPitch()*cos(fCurrentDigiPar->GetOrient()+fCurrentDigiPar->GetSkew());
  locCov[1][1]=t*t+b*b;
  locCov[2][2]=errZ*errZ;
  
  //do the transformation from sensor to lab frame
  hitCov = fGeoH->LocalToMasterErrorsShortId(locCov,sensorID);
  
  return kTRUE;
}


ClassImp(PndSdsStripClusterTask);