/* Copyright(c) 1998-2003, ALICE Experiment at CERN, All rights reserved. *
 * See cxx source for full Copyright notice                               */

///////////////////////////////////////////////////
//  Huffman Table associated classes for set:TPC //
///////////////////////////////////////////////////

 
#ifndef AliTPCHUFFMAN_H
#define AliTPCHUFFMAN_H

class AliTPCBuffer160;

class AliTPCHNode: public TObject  {
 public:
  AliTPCHNode(); //default constructor
  AliTPCHNode(Int_t symbol, Double_t freq);
  virtual ~AliTPCHNode() {}
  AliTPCHNode(const AliTPCHNode &source); // copy constructor
  AliTPCHNode& operator=(const AliTPCHNode &source); // ass. op.

  Bool_t  IsSortable() const{return kTRUE;}
  Int_t   Compare(const TObject *obj) const;
  void    SetLeft(AliTPCHNode* point){fLeft=point;}
  void    SetRight(AliTPCHNode* point){fRight=point;}
  AliTPCHNode* GetRight()const{return fRight;}
  AliTPCHNode* GetLeft()const{return fLeft;}
  void     SetSymbol(Int_t sym){fSymbol=sym;}
  void     SetFrequency(Double_t freq){fFrequency=freq;}
  Double_t GetFrequency()const{return fFrequency;}
  Int_t    GetSymbol()const{return fSymbol;}

 private:
  Int_t         fSymbol;       // Symbols
  Double_t      fFrequency;    // Frequency of the Symbol
  AliTPCHNode   *fLeft;        // Pointer to the left son
  AliTPCHNode   *fRight;       // Pointer to the right son
  ClassDef(AliTPCHNode,1)     
};
/////////////////////////////////////////////////////////////////////////////////////////////////
class AliTPCHTable: public TObject{ 
 public:
  AliTPCHTable(); 
  AliTPCHTable(Int_t size);
  virtual   ~AliTPCHTable();
  AliTPCHTable(const AliTPCHTable &source); // copy constructor
  AliTPCHTable& operator=(const AliTPCHTable &source); // ass. op.
  
  Int_t      Size()const {return fSize;}
  UChar_t*   CodeLen()const {return fCodeLen;}
  Double_t*  Code()const {return fCode;}
  Short_t*   Sym()const {return fSym;}
  void       SetCodeLen(UChar_t len,Int_t val);
  void       SetCode(Double_t code,Int_t val);
  TObjArray* HNodes()const {return fHNodes;}
  void       PrintTable()const;
  //This method builds the Huffman tree starting from the frequencies that are 
  //strored temporary in fCode array
  Int_t      BuildHTable();
  //This method returns the number of words stored in the fSym array
  ULong_t    GetWordsNumber()const{return fNum;}
  //This method increase by one the frequency of each value that is present
  //in the specified file
  Int_t      GetFrequencies(const char* fname);
  //This method increase by one the frequency of a given value
  Int_t      SetFrequency(const Int_t Val);
  //This method stores the frequency of the symbol in a text file
  Int_t      StoreFrequencies(const char *fname)const;
  void       CompleteTable(Int_t k);
  Double_t   GetEntropy()const;
  void       SetVerbose(Int_t val){fVerbose=val;}
  //Method to set directly a frequency 
  Int_t      SetValFrequency(const Int_t Val,Double_t Value);
 private:
  //This method executes the pre-order visit of an Huffman tree and calculates the 
  //codeword for each leaf
  Bool_t     SpanTree(AliTPCHNode*start, ULong_t code, UChar_t len);
  void       ResetHNodes();  //Reset the array fHNodes but not delete the removed objects
  void       ClearTable();   //Reset the table
  Int_t       fSize;         //size of the arrays fCodelen and fCode
  UChar_t     *fCodeLen;     //![fSize] number of bits array
  Double_t    *fCode;        //![fSize] coded symbols array
  
  Short_t    *fSym;          //![fSize] array of input symbols
  TObjArray  *fHNodes;       // array of nodes
  Int_t       fNnodes;       // number of nodes
  ULong_t     fNum;          // number of words
  Int_t       fVerbose;      // if fVerbose== 0 no output messages; fVerbose!=0 output messages are printed out 
  ClassDef(AliTPCHTable,1)   //Huffman Table object for set:TPC
};
#endif