// $Id$
// Main authors: Matevz Tadel & Alja Mrak-Tadel: 2006, 2007

/**************************************************************************
 * Copyright(c) 1998-2008, ALICE Experiment at CERN, all rights reserved. *
 * See http://aliceinfo.cern.ch/Offline/AliRoot/License.html for          *
 * full copyright notice.                                                 *
 **************************************************************************/

void esd_v0_init_rectrack(TEveRecTrack& rt, AliExternalTrackParam* tp)
{
  Double_t      pbuf[3], vbuf[3];

  rt.fSign = tp->GetSign();
  tp->GetXYZ(vbuf);     rt.fV.Set(vbuf);
  tp->GetPxPyPz(pbuf);  rt.fP.Set(pbuf);
  // Double_t ep = at->GetP(), mc = at->GetMass();
  rt.fBeta = 1; // ep/TMath::Sqrt(ep*ep + mc*mc);
}

AliEveV0* esd_make_v0(TEveTrackPropagator* rnrStyle, AliESDVertex* primVtx,
		      AliESDtrack* neg, AliESDtrack* pos, AliESDv0* v0, Int_t i)
{
  if (! v0->GetOnFlyStatus())
  { // v0 on fly do not have the momentum vector filled...
    TEveRecTrack  rcPos;
    TEveRecTrack  rcNeg;
    TEveRecV0     rcV0;

    Double_t p[3];
    v0->GetNPxPyPz(p[0], p[1], p[2]);
    rcV0.fPPos.Set(p);
    v0->GetPPxPyPz(p[0], p[1], p[2]);
    rcV0.fPNeg.Set(p);

    v0->GetPxPyPz(p[0], p[1], p[2]);
    Double_t v[3];
    v0->GetXYZ(v[0], v[1], v[2]);

    //   printf(" %f %f %f / %f %f %f    %i\n",p[0], p[1], p[2],
    // 	 v[0], v[1], v[2], v0->GetOnFlyStatus());

    rcV0.fVNeg.Set(v); //original track vertices at dca not stored
    rcV0.fVPos.Set(v);
    rcV0.fVCa.Set(v);

    rcV0.fDLabel[0] = v0->GetNindex();
    rcV0.fDLabel[1] = v0->GetPindex();

    esd_v0_init_rectrack(rcNeg, v0->GetParamN());
    esd_v0_init_rectrack(rcPos, v0->GetParamP());

    AliEveV0* myV0 = new AliEveV0(&rcNeg, &rcPos, &rcV0, rnrStyle);
    char ch[50];
    //   sprintf(ch,"ESDv0%i",i);
    //   myV0->SetName(ch);
    //   myV0->SetTitle(ch);
    myV0->SetESDIndex(i);
    myV0->SetDaughterDCA(v0->GetDcaV0Daughters());

    return myV0;
  } else {
    return 0;
  }
}


AliEveV0List* esd_V0(Double_t min_pt=0.1, Double_t max_pt=100)
{
  AliESDEvent* esd = AliEveEventManager::AssertESD();
  AliESDVertex* primVertex =(AliESDVertex*) esd->GetVertex();

  AliEveV0List* cont = new AliEveV0List("ESD v0");
  cont->SetMainColor(Color_t(3)); // green
  TEveTrackPropagator* rnrStyle = cont->GetPropagator();
  rnrStyle->SetMagField( 0.1*esd->GetMagneticField() );

  gEve->AddElement(cont);

  Int_t count = 0;
  //for (Int_t n=0; count<3; n++) {
  for (Int_t n=0; n<esd->GetNumberOfV0s(); n++) {

    AliESDv0 *v0 = esd->GetV0(n);
    if (v0->GetOnFlyStatus()) continue;

    Int_t negInd = v0->GetNindex();
    Int_t posInd = v0->GetPindex();
    AliESDtrack* negTr = esd->GetTrack(negInd);
    AliESDtrack* posTr = esd->GetTrack(posInd);

    AliEveV0* myV0 = esd_make_v0(rnrStyle, primVertex, negTr,posTr, v0, n);
    if (myV0) {
      gEve->AddElement(myV0, cont);
      count++;
    }
  }

  cont->SetTitle("test");
  cont->UpdateItems();

  cont->MakeV0s();
  gEve->Redraw3D();

  return cont;
}