#ifndef TCOMETOutputMerged_hxx_seen
#define TCOMETOutputMerged_hxx_seen

#include <TROOT.h>

#include <ICOMETOutput.hxx>
#include <ISHAHashValue.hxx>
#include <EoaCore.hxx>

class TChain;
class TGeoManager;

namespace COMET {
    class ICOMETEvent;
    class ICOMETInput;
    class ICOMETOutputMerged;
    class IFieldDescription;
    class IDataVector;

    /// Base class for output errors.
    OA_EXCEPTION(ECOMETOutputMerged, EoaCore);
    /// An error occurred during file merging.
    OA_EXCEPTION(ECOMETOutputMergedAddFileFailed, ECOMETOutputMerged);
    /// An error occurred during WriteEvent.
    OA_EXCEPTION(ECOMETOutputMergedDiffGeom, ECOMETOutputMergedAddFileFailed);
    /// An error occurred during AddList
    OA_EXCEPTION(ECOMETOutputAddListFailed, ECOMETOutputMergedAddFileFailed);
}

/// Extends the basic COMET output class to also write IEntryLists to the file.
/// These are stored at the same level as the ICOMETEvent tree.
class COMET::ICOMETOutputMerged : public ICOMETOutput {
public:
    /// Open a new output file.
    ICOMETOutputMerged(const char* name,
                Option_t* opt="CREATE",
                Int_t compress = 1);

    virtual ~ICOMETOutputMerged(void);

    /// Ensure the list container is written when the file is closed
    virtual void Close(Option_t* opt = "");
    /// Add a file to the output
    virtual void AddFile(ICOMETInput* inFile, bool addEntryList=true);
    /// Check the file to be added has the same geometry as previous added
    /// files, if any
    bool CheckGeometry(ICOMETInput* inFile);
    /// Check the file to be added has the same EM field as previous added
    /// files, if any
    bool CheckEMField(ICOMETInput* inFile);
    /// Add this tree to the event tree in the file
    void AddToTree(TTree* inTree);
    /// Create the container for all entry lists
    void CreateEntryListContainer();
    /// Write the container for all entry lists
    void WriteEntryListContainer();
    /// Add an entry list corresponding to a file with a given number of entries
    void AddEntryList(const char* fileName, int nEntries, int entryID=-1);

    /// Default name for the entry list container
    static const char* listContName;
    
private:
    ICOMETOutputMerged(const ICOMETOutputMerged& aFile);

    IDataVector* fListContainer; /// Container for all lists
    int fNumFiles; /// Number of files merged
    ISHAHashValue fGeomHash; /// Geometry hash
    
    ClassDef(ICOMETOutputMerged,0);
};
#endif