/**************************************************************************
 * 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.                  *
 **************************************************************************/

#include <fstream>
#include <TRandom.h>
#include "Riostream.h"

#include "AliMUONTriggerEfficiencyCells.h"
#include "AliMUONConstants.h"
#include "AliRun.h"
#include "AliMpPad.h"
#include "AliMUON.h"
#include "AliMpVSegmentation.h"
#include "AliMpTriggerSegmentation.h"
#include "AliMpTrigger.h"
#include "AliLog.h"

//
// A class to store and give access to the trigger chamber efficiency.
//
// Efficiency is stored per cathode, on "cells" of a given size.
//
// The main method of this class is IsTriggered().
//
// $ALICE_ROOT/MUON/data/TriggerChamberefficiencyCells.dat contains efficiency 
// for each chamber (i.e. DetElement). 
// The efficiency cells goes from right to left and 
// from bottom to top of the chamber, namely, the efficiencies tabulated in the 
// file refers to the following reference frame:
//
//x
//<----------------------------------|
//                                   |
//   ---------------------------     |
//  | 0.97 | 0.97 | 0.97 | 0.97 |    |
//   ---------------------------     |
//  | 0.97 | 0.97 | 0.97 | 0.97 |    |
//   ---------------------------     |
//  | 0.97 | 0.97 | 0.97 | 0.97 |    |
//   ---------------------------     |
//                                   |
//                                  \/ y
//
//  The file can be edited in order to change efficiency in a chosen region
//  of the chamber.
//
// But please note that this object is also available from the CDB 
// (generated using the MUONCDB.C macro)
//

ClassImp(AliMUONTriggerEfficiencyCells)

//__________________________________________________________________________
AliMUONTriggerEfficiencyCells::AliMUONTriggerEfficiencyCells()
:
TObject()
{
  // Default ctor.
  Reset();
}

//__________________________________________________________________________
AliMUONTriggerEfficiencyCells::AliMUONTriggerEfficiencyCells(const char* filename)
:
TObject()
{
  // Ctor using an ASCII file.
  Reset();
  ReadFile(filename);
}


//__________________________________________________________________________
AliMUONTriggerEfficiencyCells::~AliMUONTriggerEfficiencyCells()
{
  // dtor. Does nothing ;-)
}
    
//__________________________________________________________________________
Float_t AliMUONTriggerEfficiencyCells::GetCellEfficiency(Int_t detElemId, Int_t cathode, Float_t x, Float_t y)
{
  // Get the efficiency at a given position (x,y) for a given cathode
  
  Int_t chamber = FindChamberIndex(detElemId);
  Int_t slat = FindSlatIndex(detElemId);
  TArrayI cell = CellByCoord(detElemId,x,y);
  Float_t efficiency = 0.0;
  if (cell.At(0)>=0 && cell.At(1)>=0)
  {
    efficiency = fCellContent[chamber][slat][cathode][cell.At(0)][cell.At(1)];
  }
  return efficiency;
}


//__________________________________________________________________________
void AliMUONTriggerEfficiencyCells::GetCellEfficiency(Int_t detElemId, Float_t x, Float_t y, Float_t &eff1, Float_t &eff2)
{
  // Get the efficiencies of the 2 cathode at a given location (x,y)
  Int_t chamber = FindChamberIndex(detElemId);
  Int_t slat = FindSlatIndex(detElemId);
  TArrayI cell = CellByCoord(detElemId,x,y);
  eff1 = 0.0;
  eff2 = 0.0;
  if(cell.At(0)>=0 && cell.At(1)>=0)
  {
    eff1 = fCellContent[chamber][slat][0][cell.At(0)][cell.At(1)];
    eff2 = fCellContent[chamber][slat][1][cell.At(0)][cell.At(1)];
  }
}


//__________________________________________________________________________
Bool_t 
AliMUONTriggerEfficiencyCells::IsTriggered(Int_t detElemId, Int_t cathode, Float_t x, Float_t y)
{
  // Random decision of whether a given "location" (x,y) trigs or not.
  Float_t efficiency = GetCellEfficiency(detElemId, cathode, x, y);
  Bool_t trigger = kTRUE;
  if(gRandom->Rndm()>efficiency)
  {
    trigger = kFALSE;
  }
  return trigger;
}


//__________________________________________________________________________
void 
AliMUONTriggerEfficiencyCells::IsTriggered(Int_t detElemId, Float_t x, Float_t y, Bool_t &trig1, Bool_t &trig2)
{
  // Whether or not a given location (x,y) has a chance to trig, on each cathode.
  Float_t eff1 = 0.0;
  Float_t eff2 = 0.0;
  GetCellEfficiency(detElemId, x, y, eff1, eff2);
  trig1 = kTRUE; 
  trig2 = kTRUE;
  if(gRandom->Rndm()>eff1)trig1 = kFALSE;
  if(gRandom->Rndm()>eff2)trig2 = kFALSE;
}


//__________________________________________________________________________
TArrayI AliMUONTriggerEfficiencyCells::CellByCoord(Int_t detElemId, Float_t x, Float_t y)
{
  // Get the efficiencies at a given location.
  Int_t chamber = FindChamberIndex(detElemId);
  Int_t slat = FindSlatIndex(detElemId);
  Int_t cell[2]={-1,-1};
  Float_t maxX = fCellSize[chamber][slat][0]*((Float_t)fCellNumber[chamber][slat][0]);
  Float_t maxY = fCellSize[chamber][slat][1]*((Float_t)fCellNumber[chamber][slat][1]);
  if(x>=0 & x<maxX & y>=0 & y<maxY)
  {
    cell[0] = (Int_t)(x/fCellSize[chamber][slat][0]);
    cell[1] = (Int_t)(y/fCellSize[chamber][slat][1]);
  }
  return TArrayI(2,cell);
}

//__________________________________________________________________________
void AliMUONTriggerEfficiencyCells::ReadFile(const char* filename)
{
  // Reads a file containing the efficiency map.
  TString fileName = gSystem->ExpandPathName(filename);
  ifstream file(fileName.Data());
  Int_t datInt=0, detEl=0, chamber=0, rpc=0;
  Float_t datFloat=0.0;
  char dat[50];
  if (file.good()){
    while (file >> dat) {
	    file >> detEl;
	    chamber = FindChamberIndex(detEl);
	    rpc = FindSlatIndex(detEl);
	    file >> dat;
	    for(Int_t i=0; i<2; i++){
        file >> datInt;
        fCellNumber[chamber][rpc][i] = datInt;
        file >> dat;
	    }
	    for(Int_t i=0; i<2; i++){
        file >> datFloat;
        fCellSize[chamber][rpc][i] = datFloat;
        if(i==0)file >> dat;
	    }
	    for(Int_t cath=0; cath<2; cath++){
        file >> dat;
        file >> datInt;
        for(Int_t iy=0; iy<fCellNumber[chamber][rpc][1]; iy++){
          for(Int_t ix=0; ix<fCellNumber[chamber][rpc][0]; ix++){
            file >> datFloat;
            fCellContent[chamber][rpc][cath][ix][iy] = datFloat;
          }
        }
	    }
    }
    file.close();
  } else {
    AliWarning(Form("Can't read file %s",fileName.Data()));
  }
}


//__________________________________________________________________________
Int_t AliMUONTriggerEfficiencyCells::FindChamberIndex(Int_t detElemId)
{
  // From detElemId to chamber number
  Int_t offset = 100*(AliMUONConstants::NTrackingCh()+1);
  Int_t chamber = (detElemId-offset)/100;
  return chamber;
}


//__________________________________________________________________________
Int_t AliMUONTriggerEfficiencyCells::FindSlatIndex(Int_t detElemId)
{
  // From detElemId to slat index.
  Int_t offset = 100*(AliMUONConstants::NTrackingCh()+1);
  Int_t chamber = FindChamberIndex(detElemId);
  Int_t slat = detElemId-offset-(chamber*100);
  return slat;
}


//__________________________________________________________________________
TVector2 AliMUONTriggerEfficiencyCells::ChangeReferenceFrame(Float_t x, Float_t y, Float_t x0, Float_t y0)
{
    //(x0,y0) position of the local reference frame (center of the chamber)
    Float_t x1 = x0-x;//reflection of axis
    Float_t y1 = y+y0;
    return TVector2(x1,y1);
}

//__________________________________________________________________________
void
AliMUONTriggerEfficiencyCells::Reset()
{
  //
  // Sets our internal array contents to zero.
  //
  for(Int_t chamber=0; chamber<4; chamber++)
  {
    for(Int_t slat=0; slat<18; slat++)
    {
	    for(Int_t cath=0; cath<2; cath++)
      {
        fCellSize[chamber][slat][cath]=0.0;
        fCellNumber[chamber][slat][cath]=0;
        for(Int_t ix=0; ix<fgkNofCells; ix++)
        {
          for(Int_t iy=0; iy<fgkNofCells; iy++)
          {
            fCellContent[chamber][slat][cath][ix][iy]=0.0;
          }
        }
	    }
    }
  }
}