#ifndef ALIANALYSISTASK_H
#define ALIANALYSISTASK_H
/* Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
 * See cxx source for full Copyright notice                               */

/* $Id$ */
// Author: Andrei Gheata, 31/05/2006

//==============================================================================
//   AliAnalysysTask - Class representing a basic analysis task. Any
// user-defined task should derive from it and implement the Exec() virtual
// method.
//==============================================================================

#ifndef ROOT_TTask
#include "TTask.h"
#endif

#ifndef ROOT_TObjArray
#include "TObjArray.h"
#endif

class TClass;
class AliAnalysisDataSlot;
class AliAnalysisDataContainer;

class AliAnalysisTask : public TTask {
public:
enum EAnalysisTaskFlags {
   kTaskUsed    = BIT(14),
   kTaskZombie  = BIT(15),
   kTaskChecked = BIT(16)
};   
protected:
   // Define the input/output slots (called by user in the ctor of the derived class)
   //=== CALL IN THE CONSTRUCTOR OF DERIVED CLASS TO DEFINE INPUTS/OUTPUTS ===
   void                      DefineInput(Int_t islot, TClass *type);
   void                      DefineOutput(Int_t islot, TClass *type);
   //=====================================================================

   // Post output data (called by Exec() when data is ready)
   //=== CALL IN EXEC() FOR EACH OUTPUT WHEN READY ===
   Bool_t                    PostData(Int_t iout, TObject *data, Option_t *option="");
   //=====================================================================

public:
   AliAnalysisTask();
   AliAnalysisTask(const char *name, const char *title);
   AliAnalysisTask(const AliAnalysisTask &task); 
   virtual ~AliAnalysisTask();
   
   // Assignment
   AliAnalysisTask& operator=(const AliAnalysisTask &task);
   // Conect inputs/outputs to data containers (by AliAnalysisModule)
   Bool_t                    ConnectInput(Int_t islot, AliAnalysisDataContainer *cont);
   Bool_t                    ConnectOutput(Int_t islot, AliAnalysisDataContainer *cont);
   // Check connectivity
   Bool_t                    AreSlotsConnected();
   // Check if data for all inputs is ready
   void                      CheckNotify();
   // Check if there are illegal circular dependencies
   Bool_t                    CheckCircularDeps();
   // Getters
   Int_t                     GetNinputs() const  {return fNinputs;}
   Int_t                     GetNoutputs() const {return fNoutputs;}
   TObject                  *GetPublishedData() const {return fPublishedData;}
   AliAnalysisDataSlot      *GetInputSlot(Int_t islot) const  {return (AliAnalysisDataSlot*)fInputs->At(islot);}
   AliAnalysisDataSlot      *GetOutputSlot(Int_t islot) const {return (AliAnalysisDataSlot*)fOutputs->At(islot);}
   TClass                   *GetInputType(Int_t islot) const;
   TClass                   *GetOutputType(Int_t islot) const;
   // === USE THIS TO RETREIVE INPUT DATA AND STATICALLY CAST IT TO THE DECLARED TYPE
   TObject                  *GetInputData(Int_t islot) const;
   //=====================================================================
   Bool_t                    IsOutputReady(Int_t islot) const {return fOutputReady[islot];}
   Bool_t                    IsChecked() const  {return TObject::TestBit(kTaskChecked);}
   Bool_t                    IsReady() const  {return fReady;}
   Bool_t                    IsUsed() const   {return TObject::TestBit(kTaskUsed);}
   Bool_t                    IsZombie() const {return TObject::TestBit(kTaskZombie);}
   void                      PrintTask(Option_t *option="all", Int_t indent=0) const;
   void                      PrintContainers(Option_t *option="all", Int_t indent=0) const;
   void                      SetChecked(Bool_t flag=kTRUE) {TObject::SetBit(kTaskChecked,flag);}
   void                      SetUsed(Bool_t flag=kTRUE);
   void                      SetZombie(Bool_t flag=kTRUE) {TObject::SetBit(kTaskZombie,flag);}
   // Main task execution 
   //=== IMPLEMENT THIS !!! ==============================================
   virtual void              Exec(Option_t *option) = 0;
   //=====================================================================
   Bool_t                    HasExecuted() const {return fHasExecuted;}
   
protected:
   Bool_t                    fReady;      // Flag if the task is ready
   Int_t                     fNinputs;    // Number of inputs
   Int_t                     fNoutputs;   // Number of outputs
   Bool_t                   *fOutputReady; //[fNoutputs] Flags for output readyness
   TObject                  *fPublishedData; // !published data
   TObjArray                *fInputs;     // Array of input slots
   TObjArray                *fOutputs;    // Array of output slots
   
   ClassDef(AliAnalysisTask,1)  // Class describing an analysis task
};
#endif