libRocket/Include/Rocket/Core/ElementReference.h

/*
 * This source file is part of libRocket, the HTML/CSS Interface Middleware
 *
 * For the latest information, see http://www.librocket.com
 *
 * Copyright (c) 2008-2010 CodePoint Ltd, Shift Technology Ltd
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 *
 */

#ifndef ROCKETCOREELEMENTREFERENCE_H
#define ROCKETCOREELEMENTREFERENCE_H

namespace Rocket {
namespace Core {

class Element;

/**
	A smart pointer for RKTElements.

	@author Peter Curry
 */

class ElementReference
{
public:
	ElementReference(Element* element = NULL);
	ElementReference(const ElementReference& copy);
	~ElementReference();

	/// Returns true if this reference is bound to an element.
	/// @return True if this reference points to a non-NULL element, false otherwise.
	operator bool() const;

	/// Assigns a new element for this reference to point to.
	/// @param element[in] The new element.
	/// @return This element reference.
	ElementReference& operator=(Element* element);
	/// Assigns a new element for this reference, from another reference.
	/// @param element_reference[in] The element reference to copy.
	/// @return This element reference.
	ElementReference& operator=(const ElementReference& element_reference);

	/// Returns a reference to the underlying element.
	/// @return The underlying element. This may be NULL.
	Element* operator*();
	/// Returns a reference to the underlying element.
	/// @return The underlying element. This may be NULL.
	Element* operator->();

	/// Equality operator for the reference. Used for STL containers.
	/// @param rhs[in] The other element to use in the comparison.
	/// @return True if the elements are equivalent, false otherwise.
	bool operator==(const ElementReference& rhs) const;
	/// Equality operator for the reference.
	/// @param rhs[in] The other element to use in the comparison.
	/// @return True if the elements are equivalent, false otherwise.
	bool operator==(const Element* rhs) const;

	/// Less-than operator for the reference. Used for STL containers.
	/// @param rhs[in] The other element to use in the comparison.
	/// @return True if this element is less than the other element, false otherwise.
	bool operator<(const ElementReference& rhs) const;

	/// Inequality operator for the reference.
	/// @param rhs[in] The other element to use in the comparison.
	/// @return False if the elements are equivalent, true otherwise.
	bool operator!=(const ElementReference& rhs) const;
	/// Inequality operator for the reference.
	/// @param rhs[in] A raw element to use in the comparison.
	/// @return False if the elements are equivalent, true otherwise.
	bool operator!=(const Element* rhs) const;

private:
	Element* element;
};

}
}

#endif