/***************************************************************************

  PFunction.h

  Author: Andreas Suter
  e-mail: andreas.suter@psi.ch

***************************************************************************/

/***************************************************************************
 *   Copyright (C) 2007-2019 by Andreas Suter                              *
 *   andreas.suter@psi.ch                                                  *
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 *   This program is distributed in the hope that it will be useful,       *
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
 *   GNU General Public License for more details.                          *
 *                                                                         *
 *   You should have received a copy of the GNU General Public License     *
 *   along with this program; if not, write to the                         *
 *   Free Software Foundation, Inc.,                                       *
 *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
 ***************************************************************************/

#ifndef _PFUNCTION_H_
#define _PFUNCTION_H_

#include <vector>

#include <boost/version.hpp>

#if BOOST_VERSION >= 103800
#  include <boost/spirit/include/classic_ast.hpp>
   using namespace BOOST_SPIRIT_CLASSIC_NS;
#else
#  include <boost/spirit/tree/ast.hpp>
   using namespace boost::spirit;
#endif

#include <TString.h>

#include "PFunctionGrammar.h"

//----------------------------------------------------------------------------
#define OP_ADD 0
#define OP_SUB 1
#define OP_MUL 2
#define OP_DIV 3

#define FUN_COS   0
#define FUN_SIN   1
#define FUN_TAN   2
#define FUN_COSH  3
#define FUN_SINH  4
#define FUN_TANH  5
#define FUN_ACOS  6
#define FUN_ASIN  7
#define FUN_ATAN  8
#define FUN_ACOSH 9
#define FUN_ASINH 10
#define FUN_ATANH 11
#define FUN_LOG   12
#define FUN_LN    13
#define FUN_EXP   14
#define FUN_SQRT  15
#define FUN_POW   16

//----------------------------------------------------------------------------
/**
 * <p>Structure needed to evaluate a function tree (see FUNCTIONS block of an msr-file).
 */
typedef struct func_tree_node {
  Int_t    fID; ///< tag showing what tree element this is
  Int_t    fOperatorTag; ///< tag for '+', '-', '*', '/'
  Int_t    fFunctionTag; ///< tag got "cos", "sin", ...
  Int_t    fIvalue; ///< for parameter numbers and maps
  Bool_t fSign; ///< for sign, true means '-', false '+'
  Double_t fDvalue; ///< for numbers
  std::vector<func_tree_node> children; ///< holding sub-tree
} PFuncTreeNode;

//----------------------------------------------------------------------------
/**
 * <p>Class handling a function from the msr-file FUNCTIONS block.
 */
class PFunction {
  public:
    PFunction(tree_parse_info<> info);
    virtual ~PFunction();

    virtual Bool_t IsValid() { return fValid; }
    virtual Int_t GetFuncNo() { return fFuncNo; }
    virtual Bool_t CheckMapAndParamRange(UInt_t mapSize, UInt_t paramSize);
    virtual Double_t Eval(std::vector<Double_t> param);
    virtual void SetMap(std::vector<Int_t> map) { fMap = map; }

    virtual TString* GetFuncString() { return &fFuncString; }

  protected:
    virtual void InitNode(PFuncTreeNode &node);
    virtual Bool_t SetFuncNo();

    virtual Bool_t FindAndCheckMapAndParamRange(PFuncTreeNode &node, UInt_t mapSize, UInt_t paramSize);
    virtual Bool_t GenerateFuncEvalTree();
    virtual void FillFuncEvalTree(iter_t const& i, PFuncTreeNode &node);
    virtual Double_t EvalNode(PFuncTreeNode &node);
    virtual void CleanupFuncEvalTree();
    virtual void CleanupNode(PFuncTreeNode &node);

  private:
    tree_parse_info<> fInfo; ///< AST parse tree holding a single parsed msr-function in an ascii representation
    std::vector<Double_t> fParam; ///< parameter vector (from the msr-file Fit Parameter block)
    std::vector<Int_t> fMap;      ///< map vector
    PFuncTreeNode fFunc;

    Bool_t fValid; ///< flag showing if the function is valid
    Int_t fFuncNo; ///< function number, i.e. FUNx with x the function number

    virtual void EvalTreeForString(tree_parse_info<> info);
    virtual void EvalTreeForStringExpression(iter_t const& i);
    TString fFuncString; ///< clear text representation of the function
};

#endif // _PFUNCTION_H_