/*
 * $Revision: 2615 $
 *
 * last checkin:
 *   $Author: gutwenger $
 *   $Date: 2012-07-16 14:23:36 +0200 (Mo, 16. Jul 2012) $
 ***************************************************************/

/** \file
 * \brief Declaration of class HashArray2D.
 *
 * This is a class implementing a 2-dimensional Hash array.
 * It uses templates for the keys and the data of the objects
 * stored in it.
 *
 * \author René Weiskircher
 *
 * \par License:
 * This file is part of the Open Graph Drawing Framework (OGDF).
 *
 * \par
 * Copyright (C)<br>
 * See README.txt in the root directory of the OGDF installation for details.
 *
 * \par
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * Version 2 or 3 as published by the Free Software Foundation;
 * see the file LICENSE.txt included in the packaging of this file
 * for details.
 *
 * \par
 * 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.
 *
 * \par
 * 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., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 *
 * \see  http://www.gnu.org/copyleft/gpl.html
 ***************************************************************/


#ifdef _MSC_VER
#pragma once
#endif

#include <ogdf/basic/HashArray.h>
#include <ogdf/basic/tuples.h>
#include <ogdf/basic/HashIterator2D.h>

#ifndef OGDF_HASH_ARRAY_2D_H
#define OGDF_HASH_ARRAY_2D_H


namespace ogdf {


//! Indexed 2-dimensional arrays using hashing for element access.
/**
 * @tparam I1 is the first index type.
 * @tparam I2 is the second index type.
 * @tparam E  is the element type.
 * @tparam H1 is the hash function type for \a I1. Optional; uses the class DefHashFunc by default.
 * @tparam H2 is the hash function type for \a I2. Optional; uses the class DefHashFunc by default.
 *
 * A 2D-hash array can be used like a usual 2-dimensional array but with a general
 * index type.
 */
template<
	class I1,
	class I2,
	class E,
	class H1 = DefHashFunc<I1>,
	class H2 = DefHashFunc<I2> >
class HashArray2D : private Hashing< Tuple2<I1,I2>, E, HashFuncTuple<I1,I2,H1,H2> >
{
public:
	//! The type of const-iterators for 2D-hash arrays.
	typedef HashConstIterator2D<I1,I2,E,H1,H2> const_iterator;

	//! Creates a 2D-hash array.
	HashArray2D() { }

	//! Creates a 2D-hash array and sets the default value to \a x.
	HashArray2D(const E &defaultValue, const H1 &hashFunc1 = H1(), const H2 &hashFunc2 = H2()) :
		Hashing<Tuple2<I1,I2>,E,HashFuncTuple<I1,I2,H1,H2> >(
			256,
			HashFuncTuple<I1,I2,H1,H2>(hashFunc1,hashFunc2)),
		m_defaultValue(defaultValue) { }

	//! Copy constructor.
	HashArray2D(const HashArray2D<I1,I2,E,H1,H2> &A) :
		Hashing<Tuple2<I1,I2>,E,HashFuncTuple<I1,I2,H1,H2> >(A),
		m_defaultValue(A.m_defaultValue) { }

	//! Assignment operator.
	HashArray2D &operator=(const HashArray2D<I1,I2,E,H1,H2> &A) {
		m_defaultValue = A.m_defaultValue;
		Hashing<Tuple2<I1,I2>,E,HashFuncTuple<I1,I2,H1,H2> >::operator=(A);

		return *this;
	}

	~HashArray2D() { }

	//! Returns a const reference to entry (\a i,\a j).
	const E &operator()(const I1 &i, const I2 &j) const {
		HashElement<Tuple2<I1,I2>,E> *pElement =
			Hashing<Tuple2<I1,I2>,E,HashFuncTuple<I1,I2,H1,H2> >::lookup(Tuple2<I1,I2>(i,j));
		return (pElement) ? pElement->info() : m_defaultValue;
	}

	//! Returns a reference to entry (\a i,\a j).
	E &operator()(const I1 &i, const I2 &j) {
		Tuple2<I1,I2> t(i,j);
		HashElement<Tuple2<I1,I2>,E> *pElement =
			Hashing<Tuple2<I1,I2>,E,HashFuncTuple<I1,I2,H1,H2> >::lookup(t);
		if (!pElement)
			pElement = Hashing<Tuple2<I1,I2>,E,HashFuncTuple<I1,I2,H1,H2> >::fastInsert(t,m_defaultValue);
		return pElement->info();
	}

	//! Returns true iff entry (\a i,\a j) is defined.
	bool isDefined(const I1 &i, const I2 &j) const {
		return Hashing<Tuple2<I1,I2>,E,HashFuncTuple<I1,I2,H1,H2> >::member(Tuple2<I1,I2>(i,j));
	}

	//! Undefines the entry at index (\a i,\a j).
	void undefine(const I1 &i, const I2 &j) {
		return Hashing<Tuple2<I1,I2>,E,HashFuncTuple<I1,I2,H1,H2> >::del(Tuple2<I1,I2>(i,j));
	}

	//! Returns an iterator pointing to the first element.
	HashConstIterator2D<I1,I2,E,H1,H2> begin() const {
		return HashConstIterator2D<I1,I2,E>(
			Hashing<Tuple2<I1,I2>,E,HashFuncTuple<I1,I2,H1,H2> >::begin());
	}

	//! Returns the number of defined elements in the table.
	int size() const {
		return Hashing<Tuple2<I1,I2>,E,HashFuncTuple<I1,I2,H1,H2> >::size();
	}

	//! Returns if any indices are defined
	int empty() const {
		return Hashing<Tuple2<I1,I2>,E,HashFuncTuple<I1,I2,H1,H2> >::empty();
	}


	//! Undefines all indices.
	void clear() {
		Hashing<Tuple2<I1,I2>,E,HashFuncTuple<I1,I2,H1,H2> >::clear();
	}

private:
	E m_defaultValue; //!< The default value of the array.
};

}

#endif
