EcalBoundaryInfoCalculator.h

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#ifndef ECALBOUNDARYINFOCALCULATOR_H_
#define ECALBOUNDARYINFOCALCULATOR_H_
#include <memory>
#include "CondFormats/EcalObjects/interface/EcalChannelStatus.h"
#include "Geometry/CaloGeometry/interface/CaloGeometry.h"
#include "Geometry/CaloGeometry/interface/CaloSubdetectorGeometry.h"
#include "Geometry/Records/interface/CaloTopologyRecord.h"
#include "Geometry/CaloTopology/interface/CaloSubdetectorTopology.h"
#include "Geometry/CaloTopology/interface/CaloTopology.h"
#include "RecoCaloTools/Navigation/interface/EcalBarrelNavigator.h"
#include "RecoCaloTools/Navigation/interface/EcalEndcapNavigator.h"
#include "RecoCaloTools/Navigation/interface/EcalPreshowerNavigator.h"
#include "RecoCaloTools/Navigation/interface/CaloTowerNavigator.h"
#include "DataFormats/EcalDetId/interface/EcalSubdetector.h"
#include "DataFormats/EcalDetId/interface/EBDetId.h"
#include "DataFormats/EcalDetId/interface/EEDetId.h"
#include "DataFormats/EcalDetId/interface/ESDetId.h"
#include "DataFormats/EcalRecHit/interface/EcalRecHitCollections.h"
#include "DataFormats/METReco/interface/BoundaryInformation.h"
#include "FWCore/MessageLogger/interface/MessageLogger.h"
#include "FWCore/Utilities/interface/Exception.h"

enum CdOrientation { north, east, south, west, none };

template <class EcalDetId>
class EcalBoundaryInfoCalculator {
public:
  EcalBoundaryInfoCalculator();
  ~EcalBoundaryInfoCalculator();

  BoundaryInformation boundaryRecHits(const EcalRecHitCollection&,
                                      const EcalRecHit*,
                                      const CaloTopology& theCaloTopology,
                                      const EcalChannelStatus& ecalStatus,
                                      const CaloGeometry& geometry) const;

  BoundaryInformation gapRecHits(const EcalRecHitCollection&,
                                 const EcalRecHit*,
                                 const CaloTopology& theCaloTopology,
                                 const EcalChannelStatus& ecalStatus,
                                 const CaloGeometry& geometry) const;

  bool checkRecHitHasDeadNeighbour(const EcalRecHit& hit,
                                   const EcalChannelStatus& ecalStatus,
                                   std::vector<int>& stati) const {
    stati.clear();
    EcalDetId hitdetid = EcalDetId(hit.id());

    if (hitdetid.subdet() == EcalBarrel) {
      EBDetId ebhitdetid = (EBDetId)hitdetid;

      int hitIeta = ebhitdetid.ieta();
      int hitIphi = ebhitdetid.iphi();

      for (int ieta = -1; ieta <= 1; ieta++) {
        for (int iphi = -1; iphi <= 1; iphi++) {
          if ((iphi == 0 && ieta == 0) || iphi * ieta != 0)
            //if (iphi == 0 && ieta == 0)
            continue;
          int neighbourIeta = hitIeta + ieta;
          int neighbourIphi = hitIphi + iphi;
          if (!EBDetId::validDetId(neighbourIeta, neighbourIphi)) {
            if (neighbourIphi < 1)
              neighbourIphi += 360;
            if (neighbourIphi > 360)
              neighbourIphi -= 360;
            if (neighbourIeta == 0) {
              neighbourIeta += ieta;
            }
          }

          if (EBDetId::validDetId(neighbourIeta, neighbourIphi)) {
            const EBDetId detid = EBDetId(neighbourIeta, neighbourIphi, EBDetId::ETAPHIMODE);
            EcalChannelStatus::const_iterator chit = ecalStatus.find(detid);
            int status = (chit != ecalStatus.end()) ? chit->getStatusCode() & 0x1F : -1;

            if (status > 0) {
              bool present = false;
              for (std::vector<int>::const_iterator s = stati.begin(); s != stati.end(); ++s) {
                if (*s == status) {
                  present = true;
                  break;
                }
              }
              if (!present)
                stati.push_back(status);
            }
          }
        }
      }

    } else if (hitdetid.subdet() == EcalEndcap) {
      EEDetId eehitdetid = (EEDetId)hitdetid;
      int hitIx = eehitdetid.ix();
      int hitIy = eehitdetid.iy();
      int hitIz = eehitdetid.zside();

      for (int ix = -1; ix <= 1; ix++) {
        for (int iy = -1; iy <= 1; iy++) {
          if ((ix == 0 && iy == 0) || ix * iy != 0)
            //if (ix == 0 && iy == 0)
            continue;
          int neighbourIx = hitIx + ix;
          int neighbourIy = hitIy + iy;

          if (EEDetId::validDetId(neighbourIx, neighbourIy, hitIz)) {
            const EEDetId detid = EEDetId(neighbourIx, neighbourIy, hitIz, EEDetId::XYMODE);
            EcalChannelStatus::const_iterator chit = ecalStatus.find(detid);
            int status = (chit != ecalStatus.end()) ? chit->getStatusCode() & 0x1F : -1;

            if (status > 0) {
              bool present = false;
              for (std::vector<int>::const_iterator s = stati.begin(); s != stati.end(); ++s) {
                if (*s == status) {
                  present = true;
                  break;
                }
              }
              if (!present)
                stati.push_back(status);
            }
          }
        }
      }

    } else {
      edm::LogWarning("EcalBoundaryInfoCalculator") << "ERROR - RecHit belongs to wrong sub detector";
    }

    if (!stati.empty())
      return true;
    return false;
  }

  bool checkRecHitHasInvalidNeighbour(const EcalRecHit& hit, const EcalChannelStatus& ecalStatus) const {

    EcalDetId hitdetid = EcalDetId(hit.id());

    if (hitdetid.subdet() == EcalBarrel) {
      EBDetId ebhitdetid = (EBDetId)hitdetid;

      int hitIeta = ebhitdetid.ieta();
      int hitIphi = ebhitdetid.iphi();

      for (int ieta = -1; ieta <= 1; ieta++) {
        for (int iphi = -1; iphi <= 1; iphi++) {
          if ((iphi == 0 && ieta == 0) || iphi * ieta != 0)
            //if (iphi == 0 && ieta == 0)
            continue;
          int neighbourIeta = hitIeta + ieta;
          int neighbourIphi = hitIphi + iphi;
          if (!EBDetId::validDetId(neighbourIeta, neighbourIphi)) {
            if (neighbourIphi < 1)
              neighbourIphi += 360;
            if (neighbourIphi > 360)
              neighbourIphi -= 360;
            if (neighbourIeta == 0) {
              neighbourIeta += ieta;
            }
          }

          if (!EBDetId::validDetId(neighbourIeta, neighbourIphi)) {
            return true;
          }
        }
      }

    } else if (hitdetid.subdet() == EcalEndcap) {
      EEDetId eehitdetid = (EEDetId)hitdetid;
      int hitIx = eehitdetid.ix();
      int hitIy = eehitdetid.iy();
      int hitIz = eehitdetid.zside();

      for (int ix = -1; ix <= 1; ix++) {
        for (int iy = -1; iy <= 1; iy++) {
          if ((ix == 0 && iy == 0) || ix * iy != 0)
            //if (ix == 0 && iy == 0)
            continue;
          int neighbourIx = hitIx + ix;
          int neighbourIy = hitIy + iy;

          if (!EEDetId::validDetId(neighbourIx, neighbourIy, hitIz)) {
            return true;
          }
        }
      }

    } else {
      edm::LogWarning("EcalBoundaryInfoCalculator") << "ERROR - RecHit belongs to wrong sub detector";
    }

    return false;
  }

  void setDebugMode() {
    edm::LogInfo("EcalBoundaryInfoCalculator") << "set Debug Mode!";
    debug = true;
  }

private:
  EcalDetId makeStepInDirection(CdOrientation direction, const CaloNavigator<EcalDetId>* theNavi) const {
    EcalDetId next;
    switch (direction) {
      case north: {
        next = theNavi->north();
        break;
      }
      case east: {
        next = theNavi->east();
        break;
      }
      case south: {
        next = theNavi->south();
        break;
      }
      case west: {
        next = theNavi->west();
        break;
      }
      default:
        break;
    }
    return next;
  }

  CdOrientation goBackOneCell(CdOrientation currDirection, EcalDetId prev, CaloNavigator<EcalDetId>* theEcalNav) const {
    auto oIt = oppositeDirs.find(currDirection);
    CdOrientation oppDirection = none;
    if (oIt != oppositeDirs.end()) {
      oppDirection = oIt->second;
      theEcalNav->setHome(prev);
    }
    EcalDetId currDetId = theEcalNav->pos();

    return oppDirection;
  }

  CdOrientation turnRight(CdOrientation currDirection, bool reverseOrientation) const {
    //read nextDirection
    std::map<CdOrientation, CdOrientation> turnMap = nextDirs;
    if (reverseOrientation)
      turnMap = prevDirs;
    std::map<CdOrientation, CdOrientation>::iterator nIt = turnMap.find(currDirection);
    CdOrientation nextDirection = none;
    if (nIt != turnMap.end())
      nextDirection = (*nIt).second;
    else
      edm::LogWarning("EcalBoundaryInfoCalculator") << "ERROR - no Next Direction found!?!?";
    return nextDirection;
  }

  CdOrientation turnLeft(CdOrientation currDirection, bool reverseOrientation) const {
    //read nextDirection
    std::map<CdOrientation, CdOrientation> turnMap = prevDirs;
    if (reverseOrientation)
      turnMap = nextDirs;
    std::map<CdOrientation, CdOrientation>::iterator nIt = turnMap.find(currDirection);
    CdOrientation nextDirection = none;
    if (nIt != turnMap.end())
      nextDirection = (*nIt).second;
    else
      edm::LogWarning("EcalBoundaryInfoCalculator") << "ERROR - no Next Direction found!?!?";
    return nextDirection;
  }

  std::unique_ptr<CaloNavigator<EcalDetId>> initializeEcalNavigator(DetId startE,
                                                                    const CaloTopology& theCaloTopology,
                                                                    EcalSubdetector ecalSubDet) const {
    std::unique_ptr<CaloNavigator<EcalDetId>> theEcalNav;
    if (ecalSubDet == EcalBarrel) {
      theEcalNav = std::make_unique<CaloNavigator<EcalDetId>>(
          (EBDetId)startE, (theCaloTopology.getSubdetectorTopology(DetId::Ecal, ecalSubDet)));
    } else if (ecalSubDet == EcalEndcap) {
      theEcalNav = std::make_unique<CaloNavigator<EcalDetId>>(
          (EEDetId)startE, (theCaloTopology.getSubdetectorTopology(DetId::Ecal, ecalSubDet)));
    } else {
      edm::LogWarning("EcalBoundaryInfoCalculator")
          << "initializeEcalNavigator not implemented for subDet: " << ecalSubDet;
    }
    return theEcalNav;
  }

  std::map<CdOrientation, CdOrientation> nextDirs;
  std::map<CdOrientation, CdOrientation> prevDirs;
  std::map<CdOrientation, CdOrientation> oppositeDirs;
  bool debug;
};

template <class EcalDetId>
EcalBoundaryInfoCalculator<EcalDetId>::EcalBoundaryInfoCalculator() {
  nextDirs.clear();
  nextDirs[north] = east;
  nextDirs[east] = south;
  nextDirs[south] = west;
  nextDirs[west] = north;

  prevDirs.clear();
  prevDirs[north] = west;
  prevDirs[east] = north;
  prevDirs[south] = east;
  prevDirs[west] = south;

  oppositeDirs.clear();
  oppositeDirs[north] = south;
  oppositeDirs[south] = north;
  oppositeDirs[east] = west;
  oppositeDirs[west] = east;

  debug = false;
}

template <class EcalDetId>
EcalBoundaryInfoCalculator<EcalDetId>::~EcalBoundaryInfoCalculator() {}

template <class EcalDetId>
BoundaryInformation EcalBoundaryInfoCalculator<EcalDetId>::boundaryRecHits(const EcalRecHitCollection& RecHits,
                                                                           const EcalRecHit* hit,
                                                                           const CaloTopology& theCaloTopology,
                                                                           const EcalChannelStatus& ecalStatus,
                                                                           const CaloGeometry& geometry) const {
  //initialize boundary information
  std::vector<EcalRecHit> boundaryRecHits;
  std::vector<DetId> boundaryDetIds;
  std::vector<int> stati;

  double boundaryEnergy = 0;
  double boundaryET = 0;
  int beCellCounter = 0;
  bool nextToBorder = false;

  boundaryRecHits.push_back(*hit);
  ++beCellCounter;
  boundaryEnergy += hit->energy();
  EcalDetId hitdetid = (EcalDetId)hit->id();
  boundaryDetIds.push_back(hitdetid);
  const CaloSubdetectorGeometry* subGeom = geometry.getSubdetectorGeometry(hitdetid);
  auto cellGeom = subGeom->getGeometry(hitdetid);
  double eta = cellGeom->getPosition().eta();
  boundaryET += hit->energy() / cosh(eta);

  if (debug) {
    edm::LogInfo("EcalBoundaryInfoCalculator") << "Find Boundary RecHits...";

    if (hitdetid.subdet() == EcalBarrel) {
      edm::LogInfo("EcalBoundaryInfoCalculator")
          << "Starting at : (" << ((EBDetId)hitdetid).ieta() << "," << ((EBDetId)hitdetid).iphi() << ")";
    } else if (hitdetid.subdet() == EcalEndcap) {
      edm::LogInfo("EcalBoundaryInfoCalculator")
          << "Starting at : (" << ((EEDetId)hitdetid).ix() << "," << ((EEDetId)hitdetid).iy() << ")";
    }
  }

  //initialize navigator
  auto theEcalNav = initializeEcalNavigator(hitdetid, theCaloTopology, EcalDetId::subdet());
  CdOrientation currDirection = north;
  bool reverseOrientation = false;

  EcalDetId next(0);
  EcalDetId start = hitdetid;
  EcalDetId current = start;
  int current_status = 0;

  // Search until a dead cell is ahead
  bool startAlgo = false;
  int noDirs = 0;
  while (!startAlgo) {
    next = makeStepInDirection(currDirection, theEcalNav.get());
    theEcalNav->setHome(current);
    theEcalNav->home();
    EcalChannelStatus::const_iterator chit = ecalStatus.find(next);
    int status = (chit != ecalStatus.end()) ? chit->getStatusCode() & 0x1F : -1;
    if (status > 0) {
      stati.push_back(status);
      startAlgo = true;
      break;
    }
    currDirection = turnLeft(currDirection, reverseOrientation);
    ++noDirs;
    if (noDirs > 4) {
      throw cms::Exception("NoStartingDirection") << "EcalBoundaryInfoCalculator: No starting direction can be found: "
                                                     "This should never happen if RecHit has a dead neighbour!";
    }
  }

  // go around dead clusters counter clock wise
  currDirection = turnRight(currDirection, reverseOrientation);

  // Search for next boundary element
  bool nextIsStart = false;
  bool atBorder = false;

  while (!nextIsStart) {
    bool nextStepFound = false;
    int status = 0;
    noDirs = 0;
    while (!nextStepFound) {
      next = makeStepInDirection(currDirection, theEcalNav.get());
      theEcalNav->setHome(current);
      theEcalNav->home();
      EcalChannelStatus::const_iterator chit = ecalStatus.find(next);
      status = (chit != ecalStatus.end()) ? chit->getStatusCode() & 0x1F : -1;
      if (status > 0) {
        // New dead cell found: update status std::vector of dead channels
        bool present = false;
        for (std::vector<int>::const_iterator s = stati.begin(); s != stati.end(); ++s) {
          if (*s == status) {
            present = true;
            break;
          }
        }
        if (!present)
          stati.push_back(status);

        if (atBorder) {
          nextStepFound = true;
        } else {
          currDirection = turnRight(currDirection, reverseOrientation);
        }
      } else if (next == EcalDetId(0)) {
        // In case the Ecal border is reached -> go along dead cells
        currDirection = turnLeft(currDirection, reverseOrientation);
        atBorder = true;
      } else if (status == 0) {
        nextStepFound = true;
      }
      ++noDirs;
      if (noDirs > 4) {
        throw cms::Exception("NoNextDirection")
            << "EcalBoundaryInfoCalculator: No valid next direction can be found: This should never happen!";
      }
    }

    // make next step
    next = makeStepInDirection(currDirection, theEcalNav.get());

    if (next == start) {
      nextIsStart = true;
      if (debug)
        edm::LogInfo("EcalBoundaryInfoCalculator") << "Boundary path reached starting position!";
    }

    if (debug)
      edm::LogInfo("EcalBoundaryInfoCalculator")
          << "Next step: " << (EcalDetId)next << " Status: " << status << " Start: " << (EcalDetId)start;

    // save recHits and add energy if on the boundary (and not inside at border)
    if ((!atBorder || status == 0) && !nextIsStart) {
      boundaryDetIds.push_back(next);
      if (RecHits.find(next) != RecHits.end() && status == 0) {
        EcalRecHit nexthit = *RecHits.find(next);
        ++beCellCounter;
        boundaryRecHits.push_back(nexthit);
        boundaryEnergy += nexthit.energy();
        cellGeom = subGeom->getGeometry(hitdetid);
        eta = cellGeom->getPosition().eta();
        boundaryET += nexthit.energy() / cosh(eta);
      }
    }

    if (current_status == 0 && status == 0 && atBorder) {
      // this is for a special case, where dead cells are at border corner
      currDirection = turnRight(currDirection, reverseOrientation);
    } else {
      // if dead region along a border is left, turn left
      if (status == 0 && atBorder) {
        atBorder = false;
        currDirection = turnLeft(currDirection, reverseOrientation);
      }
      if (status == 0) {
        // if outside the cluster turn left to follow boundary
        currDirection = turnLeft(currDirection, reverseOrientation);
      } else {
        // else turn right to check if dead region can be left
        currDirection = turnRight(currDirection, reverseOrientation);
      }
    }

    // save currect position
    current = next;
    current_status = status;
  }

  if (debug) {
    edm::LogInfo("EcalBoundaryInfoCalculator") << "<<<<<<<<<<<<<<< Final Boundary object <<<<<<<<<<<<<<<";
    edm::LogInfo("EcalBoundaryInfoCalculator") << "no of neighbouring RecHits: " << boundaryRecHits.size();
    edm::LogInfo("EcalBoundaryInfoCalculator") << "no of neighbouring DetIds: " << boundaryDetIds.size();
    edm::LogInfo("EcalBoundaryInfoCalculator") << "boundary energy: " << boundaryEnergy;
    edm::LogInfo("EcalBoundaryInfoCalculator") << "boundary ET: " << boundaryET;
    edm::LogInfo("EcalBoundaryInfoCalculator") << "no of cells contributing to boundary energy: " << beCellCounter;
    edm::LogInfo("EcalBoundaryInfoCalculator") << "Channel stati: ";
    for (std::vector<int>::iterator it = stati.begin(); it != stati.end(); ++it) {
      edm::LogInfo("EcalBoundaryInfoCalculator") << *it << " ";
    }
    edm::LogInfo("EcalBoundaryInfoCalculator");
  }

  BoundaryInformation boundInfo;
  boundInfo.subdet = hitdetid.subdet();
  boundInfo.detIds = boundaryDetIds;
  boundInfo.recHits = boundaryRecHits;
  boundInfo.boundaryEnergy = boundaryEnergy;
  boundInfo.boundaryET = boundaryET;
  boundInfo.nextToBorder = nextToBorder;
  boundInfo.channelStatus = stati;

  return boundInfo;
}

template <class EcalDetId>
BoundaryInformation EcalBoundaryInfoCalculator<EcalDetId>::gapRecHits(const EcalRecHitCollection& RecHits,
                                                                      const EcalRecHit* hit,
                                                                      const CaloTopology& theCaloTopology,
                                                                      const EcalChannelStatus& ecalStatus,
                                                                      const CaloGeometry& geometry) const {
  //initialize boundary information
  std::vector<EcalRecHit> gapRecHits;
  std::vector<DetId> gapDetIds;

  double gapEnergy = 0;
  double gapET = 0;
  int gapCellCounter = 0;
  bool nextToBorder = false;

  gapRecHits.push_back(*hit);
  ++gapCellCounter;
  gapEnergy += hit->energy();
  EcalDetId hitdetid = (EcalDetId)hit->id();
  gapDetIds.push_back(hitdetid);
  const CaloSubdetectorGeometry* subGeom = geometry.getSubdetectorGeometry(hitdetid);
  auto cellGeom = subGeom->getGeometry(hitdetid);
  double eta = cellGeom->getPosition().eta();
  gapET += hit->energy() / cosh(eta);

  if (debug) {
    edm::LogInfo("EcalBoundaryInfoCalculator") << "Find Border RecHits...";

    if (hitdetid.subdet() == EcalBarrel) {
      edm::LogInfo("EcalBoundaryInfoCalculator")
          << "Starting at : (" << ((EBDetId)hitdetid).ieta() << "," << ((EBDetId)hitdetid).iphi() << ")";
    } else if (hitdetid.subdet() == EcalEndcap) {
      edm::LogInfo("EcalBoundaryInfoCalculator")
          << "Starting at : (" << ((EEDetId)hitdetid).ix() << "," << ((EEDetId)hitdetid).iy() << ")";
    }
  }

  //initialize navigator
  auto theEcalNav = initializeEcalNavigator(hitdetid, theCaloTopology, EcalDetId::subdet());
  CdOrientation currDirection = north;
  bool reverseOrientation = false;

  EcalDetId next(0);
  EcalDetId start = hitdetid;
  EcalDetId current = start;

  // Search until a invalid cell is ahead
  bool startAlgo = false;
  int noDirs = 0;
  while (!startAlgo) {
    next = makeStepInDirection(currDirection, theEcalNav.get());
    theEcalNav->setHome(start);
    theEcalNav->home();
    if (next == EcalDetId(0)) {
      startAlgo = true;
      nextToBorder = true;
      break;
    }
    currDirection = turnLeft(currDirection, reverseOrientation);
    ++noDirs;
    if (noDirs > 4) {
      throw cms::Exception("NoStartingDirection") << "EcalBoundaryInfoCalculator: No starting direction can be found: "
                                                     "This should never happen if RecHit is at border!";
    }
  }

  CdOrientation startDirection = currDirection;
  currDirection = turnLeft(currDirection, reverseOrientation);

  // Search for next border element
  bool endIsFound = false;
  bool startIsEnd = false;

  while (!endIsFound) {
    bool nextStepFound = false;
    int status = 0;
    noDirs = 0;
    while (!nextStepFound) {
      next = makeStepInDirection(currDirection, theEcalNav.get());
      theEcalNav->setHome(current);
      theEcalNav->home();
      EcalChannelStatus::const_iterator chit = ecalStatus.find(next);
      status = (chit != ecalStatus.end()) ? chit->getStatusCode() & 0x1F : -1;
      if (status > 0) {
        // Find dead cell along border -> end of cluster
        endIsFound = true;
        break;
      } else if (next == EcalDetId(0)) {
        // In case the Ecal border -> go along gap
        currDirection = turnLeft(currDirection, reverseOrientation);
      } else if (status == 0) {
        if (RecHits.find(next) != RecHits.end()) {
          nextStepFound = true;
        } else {
          endIsFound = true;
          break;
        }
      }
      ++noDirs;
      if (noDirs > 4) {
        throw cms::Exception("NoNextDirection")
            << "EcalBoundaryInfoCalculator: No valid next direction can be found: This should never happen!";
      }
    }

    // make next step
    next = makeStepInDirection(currDirection, theEcalNav.get());
    current = next;

    if (next == start) {
      startIsEnd = true;
      endIsFound = true;
      if (debug)
        edm::LogInfo("EcalBoundaryInfoCalculator") << "Path along gap reached starting position!";
    }

    if (debug) {
      edm::LogInfo("EcalBoundaryInfoCalculator")
          << "Next step: " << (EcalDetId)next << " Status: " << status << " Start: " << (EcalDetId)start;
      if (endIsFound)
        edm::LogInfo("EcalBoundaryInfoCalculator") << "End of gap cluster is found going left";
    }

    // save recHits and add energy
    if (!endIsFound) {
      gapDetIds.push_back(next);
      if (RecHits.find(next) != RecHits.end()) {
        EcalRecHit nexthit = *RecHits.find(next);
        ++gapCellCounter;
        gapRecHits.push_back(nexthit);
        gapEnergy += nexthit.energy();
        cellGeom = subGeom->getGeometry(next);
        eta = cellGeom->getPosition().eta();
        gapET += nexthit.energy() / cosh(eta);
      }
    }

    // turn right to follow gap
    currDirection = turnRight(currDirection, reverseOrientation);
  }

  theEcalNav->setHome(start);
  theEcalNav->home();
  current = start;
  currDirection = startDirection;
  currDirection = turnRight(currDirection, reverseOrientation);

  // Search for next border element
  endIsFound = false;

  if (!startIsEnd) {
    while (!endIsFound) {
      bool nextStepFound = false;
      int status = 0;
      noDirs = 0;
      while (!nextStepFound) {
        next = makeStepInDirection(currDirection, theEcalNav.get());
        theEcalNav->setHome(current);
        theEcalNav->home();
        EcalChannelStatus::const_iterator chit = ecalStatus.find(next);
        status = (chit != ecalStatus.end()) ? chit->getStatusCode() & 0x1F : -1;
        if (status > 0) {
          // Find dead cell along border -> end of cluster
          endIsFound = true;
          break;
        } else if (next == EcalDetId(0)) {
          // In case the Ecal border -> go along gap
          currDirection = turnRight(currDirection, reverseOrientation);
        } else if (status == 0) {
          if (RecHits.find(next) != RecHits.end()) {
            nextStepFound = true;
          } else {
            endIsFound = true;
            break;
          }
        }
        ++noDirs;
        if (noDirs > 4) {
          throw cms::Exception("NoStartingDirection")
              << "EcalBoundaryInfoCalculator: No valid next direction can be found: This should never happen!";
        }
      }

      // make next step
      next = makeStepInDirection(currDirection, theEcalNav.get());
      current = next;

      if (debug) {
        edm::LogInfo("EcalBoundaryInfoCalculator")
            << "Next step: " << (EcalDetId)next << " Status: " << status << " Start: " << (EcalDetId)start;
        if (endIsFound)
          edm::LogInfo("EcalBoundaryInfoCalculator") << "End of gap cluster is found going right";
      }

      // save recHits and add energy
      if (!endIsFound) {
        gapDetIds.push_back(next);
        if (RecHits.find(next) != RecHits.end()) {
          EcalRecHit nexthit = *RecHits.find(next);
          ++gapCellCounter;
          gapRecHits.push_back(nexthit);
          gapEnergy += nexthit.energy();
          cellGeom = subGeom->getGeometry(next);
          eta = cellGeom->getPosition().eta();
          gapET += nexthit.energy() / cosh(eta);
        }
      }

      // turn left to follow gap
      currDirection = turnLeft(currDirection, reverseOrientation);
    }
  }

  if (debug) {
    edm::LogInfo("EcalBoundaryInfoCalculator") << "<<<<<<<<<<<<<<< Final Gap object <<<<<<<<<<<<<<<";
    edm::LogInfo("EcalBoundaryInfoCalculator") << "No of RecHits along gap: " << gapRecHits.size();
    edm::LogInfo("EcalBoundaryInfoCalculator") << "No of DetIds along gap: " << gapDetIds.size();
    edm::LogInfo("EcalBoundaryInfoCalculator") << "Gap energy: " << gapEnergy;
    edm::LogInfo("EcalBoundaryInfoCalculator") << "Gap ET: " << gapET;
  }

  BoundaryInformation gapInfo;
  gapInfo.subdet = hitdetid.subdet();
  gapInfo.detIds = gapDetIds;
  gapInfo.recHits = gapRecHits;
  gapInfo.boundaryEnergy = gapEnergy;
  gapInfo.boundaryET = gapET;
  gapInfo.nextToBorder = nextToBorder;
  std::vector<int> stati;
  gapInfo.channelStatus = stati;

  return gapInfo;
}

#endif /*ECALBOUNDARYINFOCALCULATOR_H_*/