// @(#)root/hist:$Id: TFitResultPtr.cxx 37863 2011-01-24 16:50:59Z pcanal $
// Author: David Gonzalez Maline   12/11/09

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

#include "TFitResultPtr.h"
#include "TFitResult.h"
#include "TError.h"

/**
TFitResultPtr provides an indirection to the TFitResult class and with a semantics
identical to a TFitResult pointer, i.e. it is like a smart pointer to a TFitResult. 
In addition it provides an automatic comversion to an integer. In this way it can be 
returned from the TH1::Fit method and the change in TH1::Fit be backward compatible. 
The class 

 */

ClassImp(TFitResultPtr)

TFitResultPtr::TFitResultPtr(TFitResult * p) :  
   fStatus(-1), 
   fPointer(p) 
{
   // constructor from a TFitResult pointer
   if (fPointer != 0) fStatus = fPointer->Status(); 
}

TFitResultPtr::TFitResultPtr(const TFitResultPtr& rhs) : 
   fStatus(rhs.fStatus), fPointer(0)
{
   // copy constructor - create a new TFitResult if needed
   if (rhs.fPointer != 0)  fPointer = new TFitResult(*rhs);
}

TFitResultPtr::~TFitResultPtr()
{
   // destructor - delete the contained TFitResult pointer if needed
   if ( fPointer != 0)
      delete fPointer;
}


TFitResult& TFitResultPtr::operator*() const
{
   // implement the de-reference operator to make the class acts as a pointer to a TFitResult
   // assert in case the class does not contain a pointer to TFitResult
   if  (fPointer == 0) { 
      Error("TFitResultPtr","TFitResult is empty - use the fit option S");
      return *(new TFitResult() );
   }
   return *fPointer;
}

TFitResult* TFitResultPtr::operator->() const
{
   // implement the -> operator to make the class acts as a pointer to a TFitResult
   // assert in case the class does not contain a pointer to TFitResult
   if  (fPointer == 0) { 
      Error("TFitResultPtr","TFitResult is empty - use the fit option S");
      return new TFitResult();
   }
   return fPointer;
}


TFitResultPtr & TFitResultPtr::operator=(const TFitResultPtr& rhs) 
{ 
   // assignment operator
   // if needed copy the TFitResult  object and delete previous one if existing
   if ( &rhs == this) return *this; // self assignment
   fStatus = rhs.fStatus; 
   if ( fPointer ) delete fPointer;
   fPointer = 0;
   if (rhs.fPointer != 0)  fPointer = new TFitResult(*rhs);
   return *this;
}