/**************************************************************************
 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
 *                                                                        *
 * Author: The ALICE Off-line Project.                                    *
 * Contributors are mentioned in the code where appropriate.              *
 *                                                                        *
 * Permission to use, copy, modify and distribute this software and its   *
 * documentation strictly for non-commercial purposes is hereby granted   *
 * without fee, provided that the above copyright notice appears in all   *
 * copies and that both the copyright notice and this permission notice   *
 * appear in the supporting documentation. The authors make no claims     *
 * about the suitability of this software for any purpose. It is          *
 * provided "as is" without express or implied warranty.                  *
 **************************************************************************/

/*
$Log$
Revision 1.7  2000/10/18 11:42:06  morsch
- AliMUONRawCluster contains z-position.
- Some clean-up of useless print statements during initialisations.

Revision 1.6  2000/10/03 21:48:07  morsch
Adopt to const declaration of some of the methods in AliSegmentation.

Revision 1.5  2000/10/02 16:58:29  egangler
Cleaning of the code :
-> coding conventions
-> void Streamers
-> some useless includes removed or replaced by "class" statement

Revision 1.4  2000/07/03 11:54:57  morsch
AliMUONSegmentation and AliMUONHitMap have been replaced by AliSegmentation and AliHitMap in STEER
The methods GetPadIxy and GetPadXxy of AliMUONSegmentation have changed name to GetPadI and GetPadC.

Revision 1.3  2000/06/29 12:34:09  morsch
AliMUONSegmentation class has been made independent of AliMUONChamber. This makes
it usable with any other geometry class. The link to the object to which it belongs is
established via an index. This assumes that there exists a global geometry manager
from which the pointer to the parent object can be obtained (in our case gAlice).

Revision 1.2  2000/06/15 07:58:48  morsch
Code from MUON-dev joined

Revision 1.1.2.2  2000/06/12 07:57:43  morsch
include TMath.cxx

Revision 1.1.2.1  2000/06/09 21:41:29  morsch
AliMUONSegmentationV1 code  from  AliMUONSegResV1.cxx

*/


/////////////////////////////////////////////////////////
//  Manager and hits classes for set:MUON version LYON //
/////////////////////////////////////////////////////////

#include <TMath.h>
#include "AliMUONChamber.h"
#include "AliMUONSegmentationV1.h"
#include "AliRun.h"
#include "AliMUON.h"
#include "AliMUONChamber.h"

//___________________________________________
ClassImp(AliMUONSegmentationV1)

AliMUONSegmentationV1::AliMUONSegmentationV1(const AliMUONSegmentationV1& segmentation)
{
// Dummy copy constructor
}


AliMUONSegmentationV1::AliMUONSegmentationV1()

{
  // initizalize the class with default settings
    fNzone=1;
    fDAnod=0.0;
    fDpx=0.0;
    fDpx=0.0; // forces crash if not initialized by user
    fNZoneCut[0]=0;
    fSensOffset=0;
    fCorr = 0;
}


void AliMUONSegmentationV1::Init(Int_t chamber)
{
    // valid only for T5/6
    // beware : frMin is SENSITIVE radius by definition.
    AliMUON *pMUON  = (AliMUON *) gAlice->GetModule("MUON");
    AliMUONChamber* iChamber=&(pMUON->Chamber(chamber));

    frSensMin2 = (iChamber->RInner())*(iChamber->RInner());
    frSensMax2 = (iChamber->ROuter())*(iChamber->ROuter());
    fNpx=(Int_t) (iChamber->ROuter()/fDpx) + 1;
    fNpy=(Int_t) (iChamber->ROuter()/fDpy) + 1;
    //    fNwire=3;
    DefaultCut();
    fCorr=0;

    fZ = iChamber->Z();

}

void AliMUONSegmentationV1::DefaultCut(void)
{
// Set the default cuts
    SetNzone(3);
    AddCut(0,5*6,18*8);
    AddCut(0,9*6,15*8);
    AddCut(0,11*6,12*8);
    AddCut(0,12*6,9*8);
    AddCut(0,13*6,6*8);
    AddCut(1,6*6,20*12);
    AddCut(1,12*6,18*12);
    AddCut(1,15*6,15*12);
    AddCut(1,18*6,12*12);
    AddCut(1,21*6,9*12);
    SetSensOffset(3.0);
    SetDAnod(0.325);
}

Int_t AliMUONSegmentationV1::GetiAnod(Float_t xhit)
{
// Get anode number
    Int_t kwire=Int_t((TMath::Abs(xhit)-fSensOffset)/fDAnod)+1;
    return (xhit>0) ? kwire : -kwire ;
}

Float_t AliMUONSegmentationV1::GetAnod(Float_t xhit) const
{
// Get anode position
    Int_t kwire=Int_t((TMath::Abs(xhit)-fSensOffset)/fDAnod)+1; // to be compatible ...
    return (xhit>0) ? fDAnod*(kwire-0.5)+fSensOffset : -fDAnod*(kwire-0.5)-fSensOffset ;
}


void AliMUONSegmentationV1::SetPadSize(Float_t p1, Float_t p2)
{
// For chamber T5/6 p1 and p2 should be same for each zone
    fDpx=p1;
    fDpy=p2;
}

void AliMUONSegmentationV1::
GetPadI(Float_t x, Float_t y, Int_t &ix, Int_t &iy)
{
//  returns pad coordinates (ix,iy) for given real coordinates (x,y)
//
    ix = (x>0)? Int_t((x-fSensOffset)/fDpx)+1 : Int_t((x+fSensOffset)/fDpx)-1;
    iy = (y>0)? Int_t((y-fSensOffset)/fDpy)+1 : Int_t((y+fSensOffset)/fDpy)-1;
}

void AliMUONSegmentationV1::
GetPadC(Int_t ix, Int_t iy, Float_t &x, Float_t &y)
{
//  returns real coordinates (x,y) for given pad coordinates (ix,iy)
//
    x = (ix>0) ? (Float_t(ix)-0.5)*fDpx+fSensOffset : (Float_t(ix)+0.5)*fDpx-fSensOffset;
    y = (iy>0) ? (Float_t(iy)-0.5)*fDpy+fSensOffset : (Float_t(iy)+0.5)*fDpy-fSensOffset;
}

void AliMUONSegmentationV1::AddCut(Int_t Zone, Int_t nX, Int_t nY)
{
// the pad nX,nY is last INSIDE zone Zone. First pad is labelled 1 and not 0
    if (Zone+1>=fNzone) 
// no cut for last Zone : it is the natural boundary of the chamber
	printf("AliMUONSegmentationV1::AddCut ==> Zone %d not allowed !\n",Zone);
    fZoneX[Zone][fNZoneCut[Zone]] = nX;
    fZoneY[Zone][fNZoneCut[Zone]] = nY;
    fNZoneCut[Zone]++;
}

Int_t AliMUONSegmentationV1::GetZone(Float_t X, Float_t Y)
{
// Get segmentation zone
    Int_t iX, iY;
    GetPadI(X,Y,iX,iY);
    return GetZone( iX , iY );
}

Int_t AliMUONSegmentationV1::GetZone(Int_t nX, Int_t nY)
{
// Beware : first pad begins at 1 !!
    Int_t aX =  TMath::Abs(nX);
    Int_t aY =  TMath::Abs(nY);
    Int_t zone=fNzone-1;
    for (Int_t iZone=fNzone-2;iZone>=0;iZone--) 
    {
	for (Int_t iCut=0;iCut<fNZoneCut[iZone];iCut++)
	    if ( aY<=fZoneY[iZone][iCut] && aX<=fZoneX[iZone][iCut] )
	    {
		zone=iZone;
		break;
	    } 
    }
    return zone;
}

void AliMUONSegmentationV1::
SetHit(Float_t xhit, Float_t yhit)
{
// Find the wire position (center of charge distribution)
    fXhit=xhit;
    fYhit=yhit;
}

void AliMUONSegmentationV1::
SetPad(Int_t ix, Int_t iy)
{
// Set current pad position
    GetPadC(ix,iy,fX,fY);
}


void AliMUONSegmentationV1::SetPadCoord(Int_t iX, Int_t iY)
{    
// Set current pad coordinates
GetPadC(iX,iY,fX,fY);
 Float_t radius2;
 if ( ( (radius2=fX*fX+fY*fY) > frSensMax2 || radius2 < frSensMin2 ) 
      && MorePads() )
     NextPad();
}

void AliMUONSegmentationV1::FirstPad(Float_t xhit, Float_t yhit, Float_t dx, Float_t dy)
{
    //
    // Find the wire position (center of charge distribution)
    Float_t x0a=GetAnod(xhit);
    fXhit=x0a;
    fYhit=yhit;
    //
    // and take fNsigma*sigma around this center
    Float_t x01=x0a  - dx;
    Float_t x02=x0a  + dx;
    Float_t y01=yhit - dy;
    Float_t y02=yhit + dy;

    // Do not cross over frames...
    if (x01 * x0a < 0) 
      x01 = TMath::Sign(fSensOffset, x0a);
    if (x02 * x0a < 0) 
      x02 = TMath::Sign(fSensOffset, x0a);
    if (y01 * yhit < 0) 
      y01 = TMath::Sign(fSensOffset, yhit);
    if (y02 * yhit < 0) 
      y02 = TMath::Sign(fSensOffset, yhit);
    //
    // find the pads over which the charge distributes
    GetPadI(x01,y01,fIxmin,fIymin);
    GetPadI(x02,y02,fIxmax,fIymax);
    // 
    // Set current pad to lower left corner
    fIx=fIxmin;
    fIy=fIymin;
    SetPadCoord(fIx,fIy);
}

void AliMUONSegmentationV1::NextPad()
{
  // 
  // Step to next pad in integration region
    if (fIx != fIxmax) {
	fIx++;
    } else if (fIy != fIymax) {
	fIx=fIxmin;
	fIy++;
    } else 
	printf("\n Error: Stepping outside integration region\n ");
    SetPadCoord(fIx,fIy);
}

Int_t AliMUONSegmentationV1::MorePads()
{
//
// Are there more pads in the integration region

    if (fIx == fIxmax && fIy == fIymax) {
	return 0;
    } else {
	return 1;	
    }
}

Int_t AliMUONSegmentationV1::IsParallel2(Int_t iX, Int_t iY)
{
// test if the pad is read in parallel for zone 2
// iX and iY are assumed to be positive and starting at 0 numbering (cF. iX)
// returns 1 or 2 if read in parallel, 
// according to the actual number in the chain, 0 else
//
// chainage is        result is 
// 1  2  3  1  2  3   1 1 1 2 2 2     y
// 7  8  9 10 11 12   0 0 0 0 0 0     ^
// 4  5  6  4  5  6   1 1 1 2 2 2     +->x
//

    if (iY%3==1) return 0;
    return (iX%6)/3+1;
}

Int_t AliMUONSegmentationV1::IsParallel3(Int_t iX, Int_t iY)
{
// test if the pad is read in parallel for zone 3
// iX and iY are assumed to be positive and starting at 0 numbering (cF. iX)
// returns 1,2 or 3 if read in parallel, 
// according to the actual number in the chain, 0 else
//
// chainage is                 result is
//16  2  3  1  2  3  1  2  3   0 1 1 1 2 2 2 3 3
// 7  8  9 10 11 12 13 14 15   0 0 0 0 0 0 0 0 0
// 4  5  6  4  5  6  4  5  6   1 1 1 2 2 2 3 3 3
//

    if (iY%3==1) return 0;
    return (iX%9)/3+1 - (iY%3==2 && iX%3==0);
}

Int_t AliMUONSegmentationV1::NParallel2(Int_t iX, Int_t iY)
{
// returns the number of pads connected in parallel for zone 2
// iX and iY are assumed to be positive and starting at 0 numbering (cF. iX)
//
// result is
// 2 2 2 2 2 2
// 1 1 1 1 1 1
// 2 2 2 2 2 2
//

    if (iY%3==1) return 1;
    return 2;
}

Int_t AliMUONSegmentationV1::NParallel3(Int_t iX, Int_t iY)
{
// test if the pad is read in parallel for zone 3
// iX and iY are assumed to be positive and starting at 0 numbering (cF. iX)
// returns 1,2 or 3 if read in parallel, 
// according to the actual number in the chain, 0 else
//
// result is 
// 1 3 3 2 3 3 2 3 3 
// 1 1 1 1 1 1 1 1 1
// 3 3 3 3 3 3 3 3 3
//

    if (iY%3==1) return 1;
    if (iY%3==2 && iX%9==0) return 1;
    return 3 - (iY%3==2 && iX%3==0);
}


Int_t AliMUONSegmentationV1::Ix(Int_t trueX, Int_t trueY)
{
// returns the X number of pad which corresponds to the logical 
// channel, expressed in x and y.

    Int_t wix = TMath::Abs(trueX)-1;
    Int_t wiy = TMath::Abs(trueY)-1;
    Int_t zone = GetZone(trueX,trueY);
    Int_t par3;
    switch (zone) {
    case 0: return trueX;
    case 1:
	if (IsParallel2(wix,wiy) == 2)
	    return (trueX>0)? trueX-3 : trueX+3 ;
	return trueX;
    case 2:
	if ( (par3= IsParallel3(wix,wiy)) )
	    return (trueX>0) ? trueX-3*(par3-1) : trueX+3*(par3-1) ;
	return trueX ;
    default :
	printf("Couille dans AliMUONSegmentationV1::ix\n");
    }
    return -1;
}

Int_t AliMUONSegmentationV1::Ix() 
{
// returns the X number of pad which has to increment charge
// due to parallel read-out
    return Ix(fIx,fIy);
}

Int_t AliMUONSegmentationV1::ISector() 
{
// This function is of no use for this kind of segmentation.
    return GetZone(fIx,fIy);
}

void AliMUONSegmentationV1::SigGenInit(Float_t x,Float_t y,Float_t z)
{
//
//  Initialises pad and wire position during stepping
    fXt =x;
    fYt =y;
    GetPadI(x,y,fIxt,fIyt);
    fIwt= GetiAnod(x);

}

Int_t AliMUONSegmentationV1::SigGenCond(Float_t x,Float_t y,Float_t z)
{
//
//  Signal will be generated if particle crosses pad boundary or
//  boundary between two wires. 
    Int_t ixt;
    Int_t iyt;
    GetPadI(x,y,ixt,iyt);
    Int_t iwt= GetiAnod(x);
    
    if ((ixt != fIxt) || (iyt !=fIyt) || (iwt != fIwt)) {
	return 1;
    } else {
	return 0;
    }
}

void AliMUONSegmentationV1::
IntegrationLimits(Float_t& x1,Float_t& x2,Float_t& y1, Float_t& y2)
{
// Get integration limits
    x1=fXhit-fX-fDpx/2.;
    x2=x1+fDpx;
    y1=fYhit-fY-fDpy/2.;
    y2=y1+fDpy;    
}

void AliMUONSegmentationV1::GetNParallelAndOffset(Int_t iX, Int_t iY,Int_t
*Nparallel, Int_t* Offset)
{
// Get parallel pad
    Int_t wix = TMath::Abs(iX)-1;
    Int_t wiy = TMath::Abs(iY)-1;
    Int_t zone = GetZone(iX,iY);
    switch (zone) {
    case 0: 
	*Nparallel=1;
	*Offset=0;
	break;
    case 1:
	*Nparallel = NParallel2(wix,wiy);
	(iX>0) ? *Offset =3 : *Offset = -3;
	if (IsParallel2(wix,wiy)>1)
	    printf("GetNParallelAndOffset called for existing channel -> answer is crazy\n");
	break;
    case 2:
	*Nparallel = NParallel3(wix,wiy);
	(iX>0) ? *Offset =3 : *Offset = -3;
	if (IsParallel3(wix,wiy)>1)
	    printf("GetNParallelAndOffset called for existing channel -> answer is crazy\n");
	break;
    }
}


Float_t AliMUONSegmentationV1::Distance2AndOffset(Int_t iX, Int_t iY, Float_t X, Float_t Y, Int_t *Offset)
{
//
// Computes the offset for which the physical pad has the minimum distance squared
// (returned value) to the given coordinates

    Int_t nPara,offset;
    GetNParallelAndOffset(iX,iY,&nPara,&offset);
    Float_t d2min=1E10;
    for (Int_t i=0;i<nPara; i++)
    {
	Float_t x,y;
	GetPadC(iX+i*offset,iY,x,y);
	Float_t d2=(x-X)*(x-X) + (y-Y)*(y-Y);
	if ( d2min > d2)
	{
	    d2min = d2;
	    *Offset = i*offset;
	}
    }
    return d2min; 
}

void AliMUONSegmentationV1::CleanNeighbours(Int_t* Nlist, Int_t *Xlist, 
 	Int_t *Ylist)
{
// In the raw neighbours list, some pads do not exist 
// and some others are read in parallel ...
// So we prune non-existing neighbours from the list (event if this should be
// at last not be a problem due to the clustering algorithm...)

    Int_t nTot=0;
    for (Int_t nList=0;nList<*Nlist;nList++)
    {
	// prune if it does not exist
	if ( Xlist[nList]==0 || Ylist[nList]==0 )
	    continue;
	// compute true position
	Xlist[nTot] = Ix(Xlist[nList],Ylist[nList]) ;
	Ylist[nTot] = Ylist[nList] ;
	// and prune if it does already exist
	Int_t nTest;
	for (nTest=0;nTest<nTot; nTest++)
	{
	    if ( Xlist[nTest]==Xlist[nTot] && Ylist[nTest]==Ylist[nTot])
		// we found it
		break ;
	}
	if (nTest==nTot)
	    nTot++;
    }
    *Nlist = nTot;
}

void AliMUONSegmentationV1::
NeighboursNonDiag(Int_t iX, Int_t iY, Int_t* Nlist, Int_t Xlist[12], Int_t Ylist[12])
{
// returns the X number of pad which has to increment charge
// due to parallel read-out

    Int_t nParallel, offset;
    GetNParallelAndOffset(iX,iY,&nParallel,&offset);
//
// now fill raw list of neighbours
    *Nlist=4*nParallel;
    Xlist[0]=Xlist[1]=iX;Xlist[2]=iX-1;Xlist[3]=iX+1;
    Ylist[0]=iY-1;Ylist[1]=iY+1;Ylist[2]=Ylist[3]=iY;
    if (nParallel>1) {
	Xlist[4]=Xlist[5]=iX+offset;Xlist[6]=iX+offset-1;Xlist[7]=iX+offset+1;
	Ylist[4]=iY-1;Ylist[5]=iY+1;Ylist[6]=Ylist[7]=iY;
	if (nParallel>2) {
	    Xlist[8]=Xlist[9]=iX+2*offset;Xlist[10]=iX+2*offset-1;Xlist[11]=iX+2*offset+1;
	    Ylist[8]=iY-1;Ylist[9]=iY+1;Ylist[10]=Ylist[11]=iY;
	}
    }
    CleanNeighbours(Nlist,Xlist,Ylist);
}

void AliMUONSegmentationV1::
NeighboursDiag(Int_t iX, Int_t iY, Int_t* Nlist, Int_t Xlist[24], Int_t Ylist[24])
{
// returns the X number of pad which has to increment charge
// due to parallel read-out

    Int_t nParallel, offset;
    GetNParallelAndOffset(iX,iY,&nParallel,&offset);
//
// now fill raw list of neighbours
    *Nlist=0;
    for (Int_t i=0;i<nParallel;i++)
	for (Int_t dx=-1;dx<2;dx++)
	    for (Int_t dy=-1;dy<2;dy++)
	    {
		if (dx==dy && dy==0)
		    continue; 
		Xlist[*Nlist] = iX + dx + i*offset;
		Ylist[*Nlist] = iY + dy;
		(*Nlist)++;
	    }
    CleanNeighbours(Nlist,Xlist,Ylist);
}

void AliMUONSegmentationV1::Neighbours(Int_t iX, Int_t iY, Int_t* Nlist, 
				       Int_t Xlist[24], Int_t Ylist[24])
{
// Get neighbours
NeighboursDiag(iX,iY,Nlist,Xlist,Ylist);
}


void AliMUONSegmentationV1::GiveTestPoints(Int_t &n, Float_t *x, Float_t *y) const
{
// Return a test point
    n=1;
    x[0]=(TMath::Sqrt(frSensMax2)-TMath::Sqrt(frSensMin2))/2/TMath::Sqrt(2.);
    y[0]=x[0];
}

AliMUONSegmentationV1& AliMUONSegmentationV1::operator =(const AliMUONSegmentationV1 & rhs)
{
// Dummy assignment operator
    return *this;
}