// @(#)root/hbook:$Id$
// Author: Rene Brun   18/02/2002

/*************************************************************************
 * Copyright (C) 1995-2002, Rene Brun and Fons Rademakers.               *
 * All rights reserved.                                                  *
 *                                                                       *
 * For the licensing terms see $ROOTSYS/LICENSE.                         *
 * For the list of contributors see $ROOTSYS/README/CREDITS.             *
 *************************************************************************/

/** \class THbookTree
    \ingroup Hist
 A wrapper class supporting Hbook ntuples (CWN and RWN).
 The normal TTree calls can be used, including TTree::Draw().
 Data read directly from the Hbook file via THbookFile.

 IMPORTANT NOTE
 When setting the branch address (via THbookTree::SetBranchAddress)
 for a branch in an Hbook block containing several names, eg
 Hbook block SELEVN with the following variables:

~~~
 ******************************************************************
 *      1   * R*4  *         *              * SELEVN   * WGGS
 *      2   * R*4  *         *              * SELEVN   * AM12
 *      3   * R*4  *         *              * SELEVN   * AM34
 *      4   * R*4  *         *              * SELEVN   * AM14
 *      5   * R*4  *         *              * SELEVN   * AM32
 *      6   * R*4  *         *              * SELEVN   * PtPI(4)
 *      7   * R*4  *         *              * SELEVN   * PHIPI(4)
 *      8   * R*4  *         *              * SELEVN   * THTPI(4)

 one must define a C struct like:
  struct {
     Float_t Wggs;
     Float_t Am12;
     Float_t Am34;
     Float_t Am14;
     Float_t Am32;
     Float_t Ptpi[4];
     Float_t Phipi[4];
     Float_t Thtpi[4];
  } event;

 and set ONLY the first variable address with:
    h96->SetBranchAddress("Wggs",&event.Wggs);
~~~
*/

#include "THbookTree.h"
#include "THbookBranch.h"
#include "TTreeFormula.h"


ClassImp(THbookTree);

////////////////////////////////////////////////////////////////////////////////
///default constructor

THbookTree::THbookTree(): TTree()
{
   fID   = 0;
   fType = 0;
   fX    = 0;
   fFile = 0;
   fInit = kFALSE;
}

////////////////////////////////////////////////////////////////////////////////
///constructor

THbookTree::THbookTree(const char *name,Int_t id)
    :TTree(name,name)
{
   fID   = id;
   fType = 0;
   fX    = 0;
   fFile = 0;
   fInit = kFALSE;
}


////////////////////////////////////////////////////////////////////////////////
///destructor

THbookTree::~THbookTree()
{
   if (fX) delete [] fX;
   if (fFile) fFile->DeleteID(fID);
}


////////////////////////////////////////////////////////////////////////////////
///get one entry from the hbook ntuple

Int_t THbookTree::GetEntry(Long64_t entry, Int_t /*getall*/)
{
   fReadEntry = entry;
   return fFile->GetEntry(entry,fID,fType,GetX());
}


////////////////////////////////////////////////////////////////////////////////
///Initialize the branch addresses

void THbookTree::InitBranches(Long64_t entry)
{
   Int_t nfill = GetPlayer()->GetNfill();
   if (nfill > 0) {fInit = kFALSE; return;}
   if (fInit) return;
   fInit = kTRUE;
   if (!GetPlayer()->GetVar1()) {
      GetEntry(entry);
      return;
   }
   //fFile->InitLeaves(fID, 5,GetPlayer()->GetMultiplicity());
   fFile->InitLeaves(fID, 0,GetPlayer()->GetSelect());
   fFile->InitLeaves(fID, 3,GetPlayer()->GetVar3());
   fFile->InitLeaves(fID, 2,GetPlayer()->GetVar2());
   fFile->InitLeaves(fID, 1,GetPlayer()->GetVar1());
}

////////////////////////////////////////////////////////////////////////////////
///Print an overview of the hbook ntuple

void THbookTree::Print(Option_t *option) const
{
   TTree::Print(option);
}

////////////////////////////////////////////////////////////////////////////////
///Set the number of entries in the tree header and its branches

Long64_t THbookTree::SetEntries(Long64_t n)
{
   fEntries = n;
   TIter next(GetListOfBranches());
   THbookBranch *branch;
   while ((branch=(THbookBranch*)next())) {
      branch->SetEntries(n);
   }
   return n;
}