    // @(#)root/tree:$Name:  $:$Id: TLeaf.cxx,v 1.12 2004/06/22 15:36:42 brun Exp $
    // Author: Rene Brun   12/01/96

    /*************************************************************************
     * Copyright (C) 1995-2000, Rene Brun and Fons Rademakers.               *
     * All rights reserved.                                                  *
     *                                                                       *
     * For the licensing terms see $ROOTSYS/LICENSE.                         *
     * For the list of contributors see $ROOTSYS/README/CREDITS.             *
     *************************************************************************/

    //////////////////////////////////////////////////////////////////////////
    //                                                                      //
    // A TLeaf describes individual elements of a TBranch                   //
    //       See TBranch structure in TTree.                                //
    //////////////////////////////////////////////////////////////////////////

    #include "TLeaf.h"
    #include "TBranch.h"
    #include "TTree.h"
    #include "TVirtualPad.h"
    #include "TBrowser.h"

    #include <ctype.h>

    R__EXTERN TTree *gTree;
    R__EXTERN TBranch *gBranch;

    ClassImp(TLeaf)

    //______________________________________________________________________________
     TLeaf::TLeaf(): TNamed()
    {
    //*-*-*-*-*-*Default constructor for Leaf*-*-*-*-*-*-*-*-*-*-*-*-*-*
    //*-*        ============================
       fLen        = 0;
       //fBranch     = 0;
       fBranch     = gBranch;
       fLeafCount  = 0;
       fNdata      = 0;
       fOffset     = 0;
    }

    //______________________________________________________________________________
     TLeaf::TLeaf(const char *name, const char *)
        :TNamed(name,name)
    {
    //*-*-*-*-*-*-*-*-*-*-*-*-*Create a Leaf*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
    //*-*                      =============
    //
    //     See the TTree and TBranch constructors for explanation of parameters.

       fBranch     = 0;
       fIsRange    = 0;
       fIsUnsigned = 0;
       fLenType    = 4;
       fNdata      = 0;
       fOffset     = 0;

       fLeafCount  = GetLeafCounter(fLen);

       if (fLen == -1) {
          MakeZombie();
          return;
       }

       if (fLeafCount || strchr(name,'[')) {
          char newname[64];
          strcpy(newname,name);
          char *bracket = strchr(newname,'[');
          *bracket = 0;
          SetName(newname);
       }
       fBranch     = gBranch;
    }

    //______________________________________________________________________________
     TLeaf::~TLeaf()
    {
    //*-*-*-*-*-*Default destructor for a Leaf*-*-*-*-*-*-*-*-*-*-*-*
    //*-*        ===============================

    //   if (fBranch) fBranch->GetListOfLeaves().Remove(this);
       if (!fBranch) return;
       TTree *tree = fBranch->GetTree();
       fBranch = 0;
       if (!tree) return;
       tree->GetListOfLeaves()->Remove(this);
    }

    //______________________________________________________________________________
     void TLeaf::Browse(TBrowser *b)
    {
       char name[64];
       if (strchr(GetName(),'.')) {
          fBranch->GetTree()->Draw(GetName(), b ? b->GetDrawOption() : "");
       } else {
          sprintf(name,"%s.%s",fBranch->GetName(),GetName());
          fBranch->GetTree()->Draw(name, "", b ? b->GetDrawOption() : "");
       }
       if (gPad) gPad->Update();
    }

    //______________________________________________________________________________
     void TLeaf::FillBasket(TBuffer &)
    {
    //*-*-*-*-*-*-*-*-*-*-*Pack leaf elements in Basket output buffer*-*-*-*-*-*-*
    //*-*                  =========================================

    }

    //______________________________________________________________________________
     TLeaf *TLeaf::GetLeafCounter(Int_t &countval) const
    {
    //*-*-*-*-*-*-*Return Pointer to counter of referenced Leaf*-*-*-*-*-*-*-*
    //*-*          ============================================
    //
    //  If leaf name has the forme var[nelem], where nelem is alphanumeric, then
    //     If nelem is a leaf name, return countval = 1 and the pointer to
    //     the leaf named nelem.
    //  If leaf name has the forme var[nelem], where nelem is a digit, then
    //     return countval = nelem and a null pointer.
    //  Otherwise return countval=0 and a null pointer.
    //

       countval = 1;
       const char *name = GetTitle();
       char *bleft = (char*)strchr(name,'[');
       if (!bleft) return 0;
       bleft++;
       Int_t nch = strlen(bleft);
       char *countname = new char[nch+1];
       strcpy(countname,bleft);
       char *bright = (char*)strchr(countname,']');
       if (!bright) { delete [] countname; return 0;}
       char *bleft2 = (char*)strchr(countname,'[');
       *bright = 0; nch = strlen(countname);

       //*-* Now search a branch name with a leave name = countname
       //    We search for the leaf in the ListOfLeaves from the TTree. We can in principle
       //    access the TTree by calling fBranch()->GetTree(), but fBranch is not set if this
       //    method is called from the TLeaf constructor. In that case, use global pointer
       //    gTree.
       //    Also, if fBranch is set, but fBranch->GetTree() returns NULL, use gTree.
      TTree* pTree = fBranch ? fBranch->GetTree() : gTree;
      if (!pTree) pTree = gTree;
      TLeaf *leaf = (TLeaf*) pTree->GetListOfLeaves()->FindObject(countname);
      Int_t i;
      if (leaf) {
         countval = 1;
         leaf->SetRange();
         if (bleft2) {
            sscanf(bleft2,"[%d]",&i);
            countval *= i;
         }
         bleft = bleft2;
         while(bleft) {
            bleft2++;
            bleft = (char*)strchr(bleft2,'[');
            if (!bleft) break;
            sscanf(bleft,"[%d]",&i);
            countval *= i;
            bleft2 = bleft;
         }
         delete [] countname;
         return leaf;
      }
    //*-* not found in a branch/leaf. Is it a numerical value?
       for (i=0;i<nch;i++) {
          if (!isdigit(countname[i])) {
            delete [] countname;
            countval = -1;
            return 0;
          }
       }
       sscanf(countname,"%d",&countval);
       if (bleft2) {
          sscanf(bleft2,"[%d]",&i);
          countval *= i;
       }
       bleft = bleft2;
       while(bleft) {
          bleft2++;
          bleft = (char*)strchr(bleft2,'[');
          if (!bleft) break;
          sscanf(bleft,"[%d]",&i);
          countval *= i;
          bleft2 = bleft;
       }
    //*/
       delete [] countname;
       return 0;
    }

    //______________________________________________________________________________
     Int_t TLeaf::GetLen() const
    {
    //*-*-*-*-*-*-*-*-*Return the number of effective elements of this leaf*-*-*-*
    //*-*              ====================================================

       Int_t len;
       if (fLeafCount) {
          len = Int_t(fLeafCount->GetValue());
          if (len > fLeafCount->GetMaximum()) {
             printf("ERROR leaf:%s, len=%d and max=%d\n",GetName(),len,fLeafCount->GetMaximum());
             len = fLeafCount->GetMaximum();
          }
          return len*fLen;
       } else {
          return fLen;
       }
    }

    //______________________________________________________________________________
     Int_t TLeaf::ResetAddress(void *add, Bool_t destructor)
    {
    //*-*-*-*-*-*-*-*-*-*-*Set leaf buffer data address*-*-*-*-*-*
    //*-*                  ============================
    //
    //  This function is called by all TLeafX::SetAddress

       Int_t todelete = 0;
       if (TestBit(kNewValue)) todelete = 1;
       if (destructor) return todelete;

       if (fLeafCount) fNdata = fLen*(fLeafCount->GetMaximum() + 1);
       else            fNdata = fLen;

       ResetBit(kNewValue);
       if (!add) SetBit(kNewValue);
       return todelete;
    }

    //_______________________________________________________________________
     void TLeaf::SetLeafCount(TLeaf *leaf)
    {
       if (IsZombie() && fLen==-1 && leaf) {
          // The constructor noted that it could not find the
          // leafcount. Now that we did find it, let's remove
          // the side-effects
          ResetBit(kZombie);
          fLen = 1;
       }
       fLeafCount=leaf;
    }

    //_______________________________________________________________________
     void TLeaf::Streamer(TBuffer &b)
    {
    //*-*-*-*-*-*-*-*-*Stream a class object*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
    //*-*              =========================================

       if (b.IsReading()) {
          UInt_t R__s, R__c;
          Version_t R__v = b.ReadVersion(&R__s, &R__c);
          if (R__v > 1) {
             TLeaf::Class()->ReadBuffer(b, this, R__v, R__s, R__c);
          } else {
             //====process old versions before automatic schema evolution
             TNamed::Streamer(b);
             b >> fLen;
             b >> fLenType;
             b >> fOffset;
             b >> fIsRange;
             b >> fIsUnsigned;
             b >> fLeafCount;
             b.CheckByteCount(R__s, R__c, TLeaf::IsA());
             //====end of old versions
          }
          if (fLen == 0) fLen = 1;
          ResetBit(kNewValue);
          SetAddress();
       } else {
          TLeaf::Class()->WriteBuffer(b,this);
       }
    }