/* $Id$ */

/*
 * Copyright (C) 2006 Richard Braun
 * 
 * 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 _MTXVALUE_H
#define _MTXVALUE_H

#include <string>

/**
 * \def MTXVALUE_CLONE_METHOD_DECLARATION
 * \brief Allows easy decleration of clone() method in derived classes.
 */
#define MTXVALUE_CLONE_METHOD_DECLARATION(type) virtual type * clone() const

/**
 * \def MTXVALUE_CLONE_METHOD
 * \brief Allows easy implementation of clone() method in derived classes.
 */
#define MTXVALUE_CLONE_METHOD(type) \
type * \
type::clone() const \
{ \
  type *new_object; \
  new_object = new type; \
  *new_object = *this; \
  return new_object; \
}

/**
 * Abstract class for values used by the engine.
 */
class MtxValue
{
  public:
    virtual ~MtxValue();

    /**
     * Return a string representation of the value.
     */
    virtual std::string toString() const = 0;

    /**
     * Create a copy of the object and return its address.
     */
    virtual MtxValue * clone() const = 0;

    /**
     * Add the current value with the given value and return the address of
     * the result. This result must be deleted by the caller.
     */
    virtual MtxValue * add(const MtxValue *value) const = 0;

    /**
     * Subtract the given value from the current value and return the address
     * of the result. This result must be deleted by the caller.
     */
    virtual MtxValue * subtract(const MtxValue *value) const = 0;

    /**
     * Multiply the current value by the given value and return the address
     * of the result. This result must be deleted by the caller.
     */
    virtual MtxValue * multiply(const MtxValue *value) const = 0;

    /**
     * Divide the current value by the given value and return the address
     * of the result. This result must be deleted by the caller.
     */
    virtual MtxValue * divide(const MtxValue *value) const = 0;

    /**
     * Return a pointer to the opposite of the value.
     * This pointer must be deleted by the caller.
     */
    virtual MtxValue * opposite() const = 0;
};

#endif /* _MTXVALUE_H */