// $Id$

//**************************************************************************
//* This file is property of and copyright by the ALICE HLT Project        * 
//* ALICE Experiment at CERN, All rights reserved.                         *
//*                                                                        *
//* Primary Authors: Matthias Richter <Matthias.Richter@ift.uib.no>        *
//*                  for The ALICE HLT Project.                            *
//*                                                                        *
//* Permission to use, copy, modify and distribute this software and its   *
//* documentation strictly for non-commercial purposes is hereby granted   *
//* without fee, provided that the above copyright notice appears in all   *
//* copies and that both the copyright notice and this permission notice   *
//* appear in the supporting documentation. The authors make no claims     *
//* about the suitability of this software for any purpose. It is          *
//* provided "as is" without express or implied warranty.                  *
//**************************************************************************

/// @file   AliHLTMisc.h
/// @author Matthias Richter
/// @date   2009-07-07
/// @brief  Definition of various glue functions implemented in dynamically
///         loaded libraries

#include "AliHLTMisc.h"
#include "AliHLTLogging.h"
#include "TClass.h"
#include "TSystem.h"

/** ROOT macro for the implementation of ROOT specific class methods */
ClassImp(AliHLTMisc);

AliHLTMisc::AliHLTMisc()
{
  // see header file for function documentation
}

AliHLTMisc::~AliHLTMisc()
{
  // see header file for function documentation
}

AliHLTMisc* AliHLTMisc::fgInstance=NULL;

template<class T>
T* AliHLTMisc::LoadInstance(const T* /*t*/, const char* classname, const char* library)
{
  // see header file for function documentation
  int iLibResult=0;
  T* pInstance=NULL;
  AliHLTLogging log;
  TClass* pCl=NULL;
  ROOT::NewFunc_t pNewFunc=NULL;
  do {
    pCl=TClass::GetClass(classname);
  } while (!pCl && (iLibResult=gSystem->Load(library))==0);
  if (iLibResult>=0) {
    if (pCl && (pNewFunc=pCl->GetNew())!=NULL) {
      void* p=(*pNewFunc)(NULL);
      if (p) {
	pInstance=reinterpret_cast<T*>(p);
	if (!pInstance) {
	  log.Logging(kHLTLogError, "AliHLTMisc::LoadInstance", "HLT Analysis", "type cast (%s) to instance failed", classname);
	}
      } else {
	log.Logging(kHLTLogError, "AliHLTMisc::LoadInstance", "HLT Analysis", "can not create instance of type %s from class descriptor", classname);
      }
    } else {
      log.Logging(kHLTLogError, "AliHLTMisc::LoadInstance", "HLT Analysis", "can not find class descriptor %s", classname);
    }
  } else {
    log.Logging(kHLTLogError, "AliHLTMisc::LoadInstance", "HLT Analysis", "can not load %s library in order to find class descriptor %s", library, classname);
  }
  return pInstance;
}

AliHLTMisc& AliHLTMisc::Instance()
{
  // see header file for function documentation
  if (!fgInstance) {
    fgInstance=LoadInstance((AliHLTMisc*)NULL, "AliHLTMiscImplementation", ALIHLTMISC_LIBRARY);
  }
  if (!fgInstance) {
    AliHLTLogging log;
    fgInstance=new AliHLTMisc;
    log.Logging(kHLTLogError, "AliHLTMisc::Instance", "HLT Analysis", "falling back to default AliHLTMisc instance");
  }
  return *fgInstance;
}

int AliHLTMisc::InitCDB(const char* /*cdbpath*/)
{
  // see header file for function documentation
  return -EFAULT;
}

int AliHLTMisc::SetCDBRunNo(int /*runNo*/)
{
  // see header file for function documentation
  return -EFAULT;
}

AliCDBEntry* AliHLTMisc::LoadOCDBEntry(const char* /*path*/, int /*runNo*/, int /*version*/, int /*subVersion*/)
{
  // see header file for function documentation
  return NULL;
}

TObject* AliHLTMisc::ExtractObject(AliCDBEntry* /*entry*/)
{
  // see header file for function documentation
  return NULL;
}

ostream  &operator<<(ostream &out, const AliHLTComponentDataType &dt)
{
  // printout of AliHLTComponentDataType struct
  char id[kAliHLTComponentDataTypefIDsize+1];
  strncpy(id, dt.fID, kAliHLTComponentDataTypefIDsize);
  id[kAliHLTComponentDataTypefIDsize]=0;
  char origin[kAliHLTComponentDataTypefOriginSize+1];
  strncpy(origin, dt.fOrigin, kAliHLTComponentDataTypefOriginSize);
  origin[kAliHLTComponentDataTypefOriginSize]=0;
  out << "{" << id << ":" << origin << "}";
  return out;
}