//-*- Mode: C++ -*-
// $Id: AliHLTTPCCAGBHit.h,v 1.2 2010/09/01 10:38:27 ikulakov Exp $
// ************************************************************************
// This file is property of and copyright by the ALICE HLT Project        *
// ALICE Experiment at CERN, All rights reserved.                         *
// See cxx source for full Copyright notice                               *
//                                                                        *
//*************************************************************************

#ifndef ALIHLTTPCCAGBHIT_H
#define ALIHLTTPCCAGBHIT_H

#include "AliHLTTPCCADef.h"
#include "AliHLTTPCCAMath.h"
#include "ITSCAStrip.h"

#include <iostream>
using std::ostream;
using std::istream;

/**
 * @class AliHLTTPCCAGBHit
 *
 * The AliHLTTPCCAGBHit class is the internal representation
 * of the TPC clusters for the AliHLTTPCCAGBTracker algorithm.
 *
 */
class AliHLTTPCCAGBHit
{
  public:
    AliHLTTPCCAGBHit()
        : fX( 0 ), fY( 0 ), fZ( 0 ), fErr2X0( 0 ), fErr2X1( 0 ), fErrX12( 0 ), fErr2X2( 0 ),
        fIRow( 0 ), fID( 0 ), fPhi( 0 )
#if defined(DRIFT_TUBES)
        , fR( 0 ), fErr2R( 0 ), fIsLeft( false ), fIsPileuped( false ), fXW(0), fYW(0), fZW(0),
          fTubeR( 0 ), fHalfLength( 0 ), fEX( 0 ), fEY( 0 ), fEZ( 0 )
#endif
  {}

    float X() const { return fX; }
    float Y() const { return fY; }
    float Z() const { return fZ; }

    float Err2X() const { return fErr2X0; }
    float Err2Y() const { return fErr2X1; }
    float Err2Z() const { return fErr2X2; }
  
    void GetLocalX0X1X2( float& x0, float& x1, float &x2 ) const;

    float Err2X0() const { return fErr2X0; }
    float Err2X1() const { return fErr2X1; }
    float ErrX12() const { return fErrX12; }
    float Err2X2() const { return fErr2X2; }
  
    int IRow() const { return fIRow; }
    int ID() const { return fID; }

#if defined(DRIFT_TUBES)
  float R()     const { return fR; }
  float Err2R() const { return fErr2R; }
  float Err2A() const { return (fHalfLength/1.5)*(fHalfLength/1.5); }
  float Beta() const { return -0.5*atan(2*ErrX12()/(Err2X2() - Err2X1())); }
  float DistanceFromWireToPoint( float x, float y, float z ) const {
      // distance from line to point is |dr x e| / |e|
    const float dx = x - fXW;
    const float dy = y - fYW;
    const float dz = z - fZW;
    const float productX = dy*fEZ - dz*fEY;
    const float productY = dz*fEX - dx*fEZ;
    const float productZ = dx*fEY - dy*fEX;
    return sqrt( productX*productX + productY*productY + productZ*productZ ) / sqrt( fEX*fEX + fEY*fEY + fEZ*fEZ );
  }
  
  bool IsLeft() const { return fIsLeft; }
  bool IsPileduped() const { return fIsPileuped; }

  float XW() const { return fXW; }
  float YW() const { return fYW; }
  float ZW() const { return fZW; }

  float C(int i1, int i2) const { return fC[i1][i2]; }
#endif
  
    ITSCAStrip* BStripP() const {  return fBStripP; }
    ITSCAStrip* FStripP() const {  return fFStripP; }
  
    void SetX( float v ) {  fX = v; }
    void SetY( float v ) {  fY = v; }
    void SetZ( float v ) {  fZ = v; }
    void SetErr2X( float v ) {  fErr2X0 = v; }
    void SetErr2Y( float v ) {  fErr2X1 = v; }
    void SetErr2Z( float v ) {  fErr2X2 = v; }
    void SetErrYZ( float v ) {  fErrX12 = v; }
    void SetIRow( int v ) {  fIRow = v; }
    void SetID( int v ) {  fID = v; }

    void SetErr2X0( float v ) {  fErr2X0 = v; }
    void SetErr2X1( float v ) {  fErr2X1 = v; }
    void SetErrX12( float v ) {  fErrX12 = v; }
    void SetErr2X2( float v ) {  fErr2X2 = v; }
  
    void SetFStripP( ITSCAStrip* s ) {  fFStripP = s; }
    void SetBStripP( ITSCAStrip* s ) {  fBStripP = s; }

    void SetAngle( float v ) {  fPhi = v; }
    float Angle() const { return fPhi; }

#if defined(DRIFT_TUBES)
  void SetR(float v)      { fR = v; }
  void SetErr2R(float v)  { fErr2R = v; }
  void SetIsLeft(bool v)  { fIsLeft = v; }
  void SetIsPileuped(bool b) { fIsPileuped = b; }

  void SetXW( float v ) {  fXW = v; }
  void SetYW( float v ) {  fYW = v; }
  void SetZW( float v ) {  fZW = v; }

  void SetC( float v, int i1, int i2 ) {  fC[i1][i2] = v; }
#endif
  
    static bool Compare( const AliHLTTPCCAGBHit &a, const AliHLTTPCCAGBHit &b );

/// \brief Hits reordering  in accordance with the geometry and the track-finder needs:
/// Hits are sorted by sector number at first, than by row number and at last by z-coordinate

    static bool CompareRowDown( const AliHLTTPCCAGBHit &a, const AliHLTTPCCAGBHit &b ) {
      return ( a.fIRow > b.fIRow );
      
/// Hits are sorted by  row number 
    }
    static bool ComparePRowDown( const AliHLTTPCCAGBHit *a, const AliHLTTPCCAGBHit *b ) {
      return ( a->fIRow > b->fIRow );
/// Hits are sorted by  row number 
    }

  friend ostream& operator<<(ostream& out, const AliHLTTPCCAGBHit &a);
  friend istream& operator>>(istream& in, AliHLTTPCCAGBHit &a);

  protected:
    ITSCAStrip* fFStripP, *fBStripP;
  
    double fX; //* X position
    double fY; //* Y position
    double fZ; //* Z position

    float fErr2X0; //* position error^2 in local c.s. (x0 is perpendicular to station)
    float fErr2X1;
    float fErrX12; // covariance
    float fErr2X2;

    double fC[3][3]; // cov matrix in global c.s.

    int fIRow;   //* row number
    int fID;     //* external ID (id of AliTPCcluster)

    double fPhi;

#if defined(DRIFT_TUBES)
  double fR, fErr2R;
  bool fIsLeft;
  bool fIsPileuped;
  double fXW; //* X wire position
  double fYW; //* Y wire position
  double fZW; //* Z wire position

  double fTubeR, fHalfLength;
  double fEX, fEY, fEZ; // wire direction
#endif
};

inline bool AliHLTTPCCAGBHit::Compare( const AliHLTTPCCAGBHit &a, const AliHLTTPCCAGBHit &b )

/// \brief Hits reordering  in accordance with the geometry and the track-finder needs:
/// Hits are sorted by sector number at first, than by row number and at last by z-coordinate.



{
  //* Comparison function for sorting hits
  if ( a.fIRow < b.fIRow ) return 1;
  if ( a.fIRow > b.fIRow ) return 0;
  return ( a.fZ < b.fZ );
}

#endif