/* ======================================================================== *\
!
! *
! * This file is part of MARS, the MAGIC Analysis and Reconstruction
! * Software. It is distributed to you in the hope that it can be a useful
! * and timesaving tool in analysing Data of imaging Cerenkov telescopes.
! * It is distributed WITHOUT ANY WARRANTY.
! *
! * Permission to use, copy, modify and distribute this software and its
! * documentation for any purpose is hereby granted without fee,
! * provided that the above copyright notice appear in all copies and
! * that both that copyright notice and this permission notice appear
! * in supporting documentation. It is provided "as is" without express
! * or implied warranty.
! *
!
!
!   Author(s): Thomas Bretz    12/2000 <mailto:tbretz@astro.uni-wuerzburg.de>
!   Author(s): Rudolf Bock     10/2001 <mailto:Rudolf.Bock@cern.ch>
!   Author(s): Wolfgang Wittek 06/2002 <mailto:wittek@mppmu.mpg.de>
!
!   Copyright: MAGIC Software Development, 2000-2004
!
!
\* ======================================================================== */

/////////////////////////////////////////////////////////////////////////////
//
// MHillasExt
//
// Storage Container for extended image parameters
//
//    extended image parameters
//
//
// Version 1:
// ----------
// fConc     ratio of sum of two highest pixels over fSize
// fConc1    ratio of highest pixel over fSize
// fAsym     distance from highest pixel to center, projected onto major axis
// fM3Long   third moment along major axis
// fM3Trans  third moment along minor axis
//
// Version 2:
// ----------
// fConc     removed
// fConc1    removed
//
// Version 3:
// ----------
// fMaxDist  added. Distance between center and most distant used pixel
//
//
// WARNING: Before you can use fAsym, fM3Long and fM3Trans you must
//          multiply by the sign of MHillasSrc::fCosDeltaAlpha
//
////////////////////////////////////////////////////////////////////////////
/*
 // fAsymna   d/(d na) of ( sum(x*q^na)/sum(q^na), sum(y*q^na)/sum(q^na) )
 //           projected onto the major axis
 // fAsym0    (F-B)/(F+B) along the major axis
 */
#include "MHillasExt.h"

#include <TArrayF.h>

#include "MGeomPix.h"
#include "MGeomCam.h"

#include "MCerPhotPix.h"
#include "MCerPhotEvt.h"

#include "MLog.h"
#include "MLogManip.h"

#include "MHillas.h"

ClassImp(MHillasExt);

using namespace std;

// -------------------------------------------------------------------------
//
// Default constructor.
//
MHillasExt::MHillasExt(const char *name, const char *title)
{
    fName  = name  ? name  : "MHillasExt";
    fTitle = title ? title : "Storage container for extended parameter set of one event";

    Reset();
}

// -------------------------------------------------------------------------
//
void MHillasExt::Reset()
{
    fAsym    =  0;
    fM3Long  =  0;
    fM3Trans =  0;

    fMaxDist =  0;
}

// -------------------------------------------------------------------------
//
// Print contents of MHillasExt to *fLog.
//
void MHillasExt::Print(Option_t *) const
{
    *fLog << all;
    *fLog << "Extended Image Parameters (" << GetName() << ")" << endl;
    *fLog << " - Asymmetry            = " << fAsym    << endl;
    *fLog << " - 3.Moment Long  [mm]  = " << fM3Long  << endl;
    *fLog << " - 3.Moment Trans [mm]  = " << fM3Trans << endl;
    *fLog << " - Max.Dist       [mm]  = " << fMaxDist << endl;
}

// -------------------------------------------------------------------------
//
// Print contents of MHillasExt to *fLog, depending on the geometry in
// units of deg.
//
void MHillasExt::Print(const MGeomCam &geom) const
{
    *fLog << all;
    *fLog << "Extended Image Parameters (" << GetName() << ")" << endl;
    *fLog << " - Asymmetry            = " << fAsym   *geom.GetConvMm2Deg() << endl;
    *fLog << " - 3.Moment Long  [deg] = " << fM3Long *geom.GetConvMm2Deg() << endl;
    *fLog << " - 3.Moment Trans [deg] = " << fM3Trans*geom.GetConvMm2Deg() << endl;
    *fLog << " - Max.Dist       [deg] = " << fMaxDist*geom.GetConvMm2Deg() << endl;
}

// -------------------------------------------------------------------------
//
// calculation of additional parameters based on the camera geometry
// and the cerenkov photon event
//
Int_t MHillasExt::Calc(const MGeomCam &geom, const MCerPhotEvt &evt, const MHillas &hil, Int_t island)
{
    //
    //   calculate the additional image parameters
    // --------------------------------------------
    //
    //  loop to get third moments along ellipse axes and two max pixels
    //
    //  For the moments double precision is used to make sure, that
    //  the complex matrix multiplication and sum is evaluated correctly.
    //
    Double_t m3x = 0;
    Double_t m3y = 0;

    Int_t maxpixid  = 0;
    Float_t maxpix  = 0;
    Float_t maxdist = 0;

    MCerPhotPix *pix = 0;

    TIter Next(evt);
    while ((pix=(MCerPhotPix*)Next()))
    {
        if (island>=0 && pix->GetIdxIsland()!=island)
            continue;

        const Int_t pixid = pix->GetPixId();

        const MGeomPix &gpix = geom[pixid];
        const Double_t dx = gpix.GetX() - hil.GetMeanX();      // [mm]
        const Double_t dy = gpix.GetY() - hil.GetMeanY();      // [mm]

        Double_t nphot = pix->GetNumPhotons();                  // [1]

        const Double_t dzx =  hil.GetCosDelta()*dx + hil.GetSinDelta()*dy; // [mm]
        const Double_t dzy = -hil.GetSinDelta()*dx + hil.GetCosDelta()*dy; // [mm]

        const Double_t dist = dx*dx+dy*dy;
        if (TMath::Abs(dist)>TMath::Abs(maxdist))
            maxdist = dzx<0 ? -dist : dist;                    // [mm^2]

        m3x += nphot * dzx*dzx*dzx;                            // [mm^3]
        m3y += nphot * dzy*dzy*dzy;                            // [mm^3]

        //
        // Now we are working on absolute values of nphot, which
        // must take pixel size into account
        //
        nphot *= geom.GetPixRatio(pixid);

        if (nphot>maxpix)
        {
            maxpix   = nphot;                                  // [1]
            maxpixid = pixid;
            continue;                                          // [1]
        }
    }

    const MGeomPix &maxp = geom[maxpixid];

    fAsym = (hil.GetMeanX()-maxp.GetX())*hil.GetCosDelta() +
            (hil.GetMeanY()-maxp.GetY())*hil.GetSinDelta();            // [mm]

    //
    // Third moments along axes get normalized
    //
    m3x /= hil.GetSize();
    m3y /= hil.GetSize();

    fM3Long  = m3x<0 ? -pow(-m3x, 1./3) : pow(m3x, 1./3);      // [mm]
    fM3Trans = m3y<0 ? -pow(-m3y, 1./3) : pow(m3y, 1./3);      // [mm]

    const Double_t md = TMath::Sqrt(TMath::Abs(maxdist));
    fMaxDist = maxdist<0 ? -md : md;                           // [mm]

    SetReadyToSave();

    return 0;
}

// --------------------------------------------------------------------------
//
// This function is ment for special usage, please never try to set
// values via this function
//
void MHillasExt::Set(const TArrayF &arr)
{
    if (arr.GetSize() != 4)
        return;

    fAsym    = arr.At(0);
    fM3Long  = arr.At(1);
    fM3Trans = arr.At(2);
    fMaxDist = arr.At(3);
}