#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 TFile;
class AliAnalysisDataSlot;
class AliAnalysisDataContainer;

class AliAnalysisTask : public TTask {
 public:
  enum EAnalysisTaskFlags {
    kTaskUsed    = BIT(14),
    kTaskZombie  = BIT(15),
    kTaskChecked = BIT(16),
    kTaskPostEventLoop = BIT(17)
  };

 protected:
  Bool_t                    fReady;         // Flag if the task is ready
  Bool_t                    fInitialized;   // True if Init() was called
  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
  TString                   fBranchNames;   // List of input branches that need to be loaded for this task

  // 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);
  
  //=====================================================================
  // === OVERLOAD THIS TO CONNECT TREE BRANCHES AT INPUT SLOTS. YOU
  // SHOULD DEFINE HERE ALSO THE OBJECTS TO BE CONNECTED TO YOUR OUTPUTS
  virtual void              ConnectInputData(Option_t *option="");
  //=====================================================================
  
  // 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="");
  //=====================================================================
  
  // === USE THIS FIRST IN YOUR ConnectInputData() TO CHECH IF A BRANCH IS ALREADY CONNECTED
  // TO SOME ADDRESS.
  char                     *GetBranchAddress(Int_t islot, const char *branch) const;
  // === CALL THIS AFTERWARDS IN ConnectInputData() IF THE BRANCH ADDRESS IS NOT YET SET
  Bool_t                    SetBranchAddress(Int_t islot, const char *branch, void *address) const;
  //=====================================================================
  //=== CALL IN ConnectInputData() TO ENABLE ONLY EXPLICIT BRANCHES NEEDED FOR THIS TASK EXECUTION
  void                      EnableBranch(Int_t islot, const char *bname) const;
  //=====================================================================
  // === CALL THIS IN CreateOutputObjects BEFORE CREATING THE OBJECT FOR EACH 
  // OUTPUT IOUT THAT HAS TO BE WRITTEN TO A FILE
  TFile                    *OpenFile(Int_t iout, Option_t *option="RECREATE") const;
  
public:  
  AliAnalysisTask();
  AliAnalysisTask(const char *name, const char *title);
  AliAnalysisTask(const AliAnalysisTask &task); 
  virtual ~AliAnalysisTask();
  
  // Assignment
  AliAnalysisTask& operator=(const AliAnalysisTask &task);
  //=====================================================================
  // === OVERLOAD THIS AND CREATE YOUR OUTPUT OBJECTS (HISTOGRAMS,DATA) HERE
  virtual void              CreateOutputObjects();
  // === OVERLOAD THIS IF YOU NEED TO INITIALIZE YOUR CLASS ON THE CLIENT
  virtual void              LocalInit();
  // === OVERLOAD THIS IF YOU NEED TO TREAT INPUT FILE/TREE CHANGE
  virtual Bool_t            Notify();
  // === OVERLOAD THIS IF YOU NEED TO TREAT BIN CHANGE IN EVENT MIXING
  virtual Bool_t            NotifyBinChange();
  //=====================================================================
  // Optional method that will be called in SlaveTerminate phase for each task
  // Warning: in PROOF mode this is called before merging so their cleanup is
  //          not allowed - do output cleanup in class destructor.
  virtual void              FinishTaskOutput();
  // 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(Bool_t init=kFALSE);
  // Check if there are illegal circular dependencies
  Bool_t                    CheckCircularDeps();
  // Getters
  void                      GetBranches(const char *type, TString &result) const;
  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;
  TObject                  *GetOutputData(Int_t islot) const;  
  Bool_t                    IsOutputReady(Int_t islot) const {return fOutputReady[islot];}
  Bool_t                    IsChecked() const  {return TObject::TestBit(kTaskChecked);}
  Bool_t                    IsPostEventLoop() const {return TObject::TestBit(kTaskPostEventLoop);}
  Bool_t                    IsInitialized() const  {return fInitialized;}
  Bool_t                    IsReady() const  {return fReady;}
  Bool_t                    IsUsed() const   {return TObject::TestBit(kTaskUsed);}
  Bool_t                    IsZombie() const {return TObject::TestBit(kTaskZombie);}
  Bool_t                    HasBranches() const {return !fBranchNames.IsNull();}
  virtual void                      PrintTask(Option_t *option="all", Int_t indent=0) const;
  void                      PrintContainers(Option_t *option="all", Int_t indent=0) const;
  void                      SetBranches(const char *names) {fBranchNames = names;}
  void                      SetChecked(Bool_t flag=kTRUE) {TObject::SetBit(kTaskChecked,flag);}
  void                      SetPostEventLoop(Bool_t flag=kTRUE);
  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;}
  //=====================================================================
  // === OVERLOAD THIS IF YOU WANT TO DO SOMETHING WITH THE OUTPUT
  virtual void              Terminate(Option_t *option="");
  //=====================================================================
    
  ClassDef(AliAnalysisTask,2)  // Class describing an analysis task
};
#endif