// -*- mode: c++; c-basic-offset:4 -*-

// This file is part of libdap, A C++ implementation of the OPeNDAP Data

// Access Protocol.

// Copyright (c) 2014 OPeNDAP, Inc.

// Author: James Gallagher <jgallagher@opendap.org>

//

// This library is free software; you can redistribute it and/or

// modify it under the terms of the GNU Lesser General Public

// License as published by the Free Software Foundation; either

// version 2.1 of the License, or (at your option) any later version.

//

// This library 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

// Lesser General Public License for more details.

//

// You should have received a copy of the GNU Lesser General Public

// License along with this library; if not, write to the Free Software

// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA

//

// You can contact OPeNDAP, Inc. at PO Box 112, Saunderstown, RI. 02874-0112.

#ifndef _D4RValue_h

#define _D4RValue_h

#include <vector>

#include <string>

#include <dods-datatypes.h>

#include <D4Function.h>

namespace libdap

{

class BaseType;

class D4RValue;

// Factory class to build RValue objects. User by the parser/ce-evaluator

D4RValue *D4RValueFactory(std::string cpps);

class D4RValueList

{

private:

	std::vector<D4RValue *> d_rvalues;

	void m_duplicate(const D4RValueList &src;;

public:

	typedef std::vector<D4RValue *>::iterator iter;

	D4RValueList() { }

	D4RValueList(const D4RValueList &src) { m_duplicate(src); }

	D4RValueList(D4RValue *rv) { add_rvalue(rv); }

	virtual ~D4RValueList();

	void add_rvalue(D4RValue *rv) {

		d_rvalues.push_back(rv);

	}

	D4RValue *get_rvalue(unsigned int i) {

		return d_rvalues.at(i);

	}

	iter begin() { return d_rvalues.begin(); }

	iter end() { return d_rvalues.end(); }

	unsigned int size() const { return d_rvalues.size(); }

};

/**

 * Holds the RValues for the D4 function parser and for the filter

 * expression evaluator.

 */

class D4RValue

{

public:

    enum value_kind {

        unknown,

        basetype,

        function,

        constant

    };

private:

    BaseType *d_variable;	// This is a weak pointer; do not delete

    D4Function d_func;  	// (weak) pointer to a function returning BaseType *

    D4RValueList *d_args;  	// pointer to arguments to the function; delete

    BaseType *d_constant;	// pointer; delete.

    value_kind d_value_kind;

    /** @brief Clone 'src' to 'this'. */

    void m_duplicate(const D4RValue &src;;

    friend class D4RValueList;

public:

    D4RValue() : d_variable(0), d_func(0), d_args(0), d_constant(0), d_value_kind(unknown) { }

    D4RValue(const D4RValue &src) { m_duplicate(src); }

    D4RValue(BaseType *btp)  : d_variable(btp), d_func(0), d_args(0), d_constant(0), d_value_kind(basetype) { }

    D4RValue(D4Function f, D4RValueList *args)  : d_variable(0), d_func(f), d_args(args), d_constant(0), d_value_kind(function) { }

    D4RValue(unsigned long long ui);

    D4RValue(long long i);

    D4RValue(double r);

    D4RValue(std::string s);

    D4RValue(std::vector<dods_byte> &byte_args);

    D4RValue(std::vector<dods_int8> &byte_int8);

    D4RValue(std::vector<dods_uint16> &byte_uint16);

    D4RValue(std::vector<dods_int16> &byte_int16);

    D4RValue(std::vector<dods_uint32> &byte_uint32);

    D4RValue(std::vector<dods_int32> &byte_int32);

    D4RValue(std::vector<dods_uint64> &byte_uint64);

    D4RValue(std::vector<dods_int64> &byte_int64);

    D4RValue(std::vector<dods_float32> &byte_float32);

    D4RValue(std::vector<dods_float64> &byte_float64);

    virtual ~D4RValue();

    D4RValue &operator=(D4RValue &rhs) {

        if (this == &rhs)

            return *this;

        m_duplicate(rhs);

        return *this;

    }

    /**

     * @brief What kind of thing holds the value

     * Values in DAP4 constraints are either constants, dataset variables

     * or function results. It might be nice to know the source of a

     * given value in order to optimize the evaluation of certain kinds of

     * expressions.

     * @return The 'value_kind' of this value.

     */

    value_kind get_kind() const { return d_value_kind; }

    // This is the call that will be used to return the value of a function.

    // jhrg 3/10/14

    virtual BaseType *value(DMR &dmr);

    // And this optimizes value() for filters, where functions are not supported.

    virtual BaseType *value();

};

} // namespace libdap

#endif // _RValue_h