/*
 * $Revision: 2584 $
 *
 * last checkin:
 *   $Author: gutwenger $
 *   $Date: 2012-07-12 02:38:07 +0200 (Do, 12. Jul 2012) $
 ***************************************************************/

/** \file
 * \brief Declaration and implementation of ClusterArray class.
 *
 * \author Sebastian Leipert
 *
 * \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

#ifndef OGDF_CLUSTER_ARRAY_H
#define OGDF_CLUSTER_ARRAY_H


#include "../basic/Array.h"
#include "ClusterGraph.h"


namespace ogdf {


//---------------------------------------------------------
// ClusterArrayBase
// base class for ClusterArray<T>, defines interface for event handling
// used by Graph
//---------------------------------------------------------
//! Abstract base class for cluster arrays.
/**
 * Defines the interface for event handling used by the ClusterGraph class.
 * Use the paramiterized class ClusterArray for creating edge arrays.
 */
class ClusterArrayBase {
	/**
	 * Pointer to list element in the list of all registered cluster
	 * arrays which references this array.
	 */
	ListIterator<ClusterArrayBase*> m_it;

public:
	const ClusterGraph *m_pClusterGraph; //!< The associated cluster graph.

	//! Initializes a cluster array not associated with a cluster graph.
	ClusterArrayBase() : m_pClusterGraph(0) { }
	//! Initializes a cluster array associated with \a pC.
	ClusterArrayBase(const ClusterGraph *pC) : m_pClusterGraph(pC) {
		if(pC) m_it = pC->registerArray(this);
	}

	// destructor, unregisters the array
	virtual ~ClusterArrayBase() {
		if (m_pClusterGraph) m_pClusterGraph->unregisterArray(m_it);
	}

	// event interface used by Graph
	//! Virtual function called when table size has to be enlarged.
	virtual void enlargeTable(int newTableSize) = 0;
	//! Virtual function called when table has to be reinitialized.
	virtual void reinit(int initTableSize) = 0;
	//! Virtual function called when array is disconnected from the cluster graph.
	virtual void disconnect() = 0;

	//! Associates the array with a new cluster graph.
	void reregister(const ClusterGraph *pC) {
		if (m_pClusterGraph) m_pClusterGraph->unregisterArray(m_it);
		if ((m_pClusterGraph = pC) != 0) m_it = pC->registerArray(this);
	}
}; // class ClusterArrayBase


//! Dynamic arrays indexed with clusters.
/**
 * Cluster arrays adjust their table size automatically
 * when the cluster graph grows.
 */
template<class T> class ClusterArray : private Array<T>, protected ClusterArrayBase {
	T m_x; //!< The default value for array elements.

public:
	//! Constructs an empty cluster array associated with no graph.
	ClusterArray() : Array<T>(), ClusterArrayBase() { }
	//! Constructs a cluster array associated with \a C.
	ClusterArray(const ClusterGraph &C) :
		Array<T>(C.clusterArrayTableSize()),
		ClusterArrayBase(&C) { }
	//! Constructs a cluster array associated with \a C.
	/**
	 * @param C is the associated cluster graph.
	 * @param x is the default value for all array elements.
	 */
	ClusterArray(const ClusterGraph &C, const T &x) :
		Array<T>(0,C.clusterArrayTableSize()-1,x),
		ClusterArrayBase(&C), m_x(x) { }
	//! Constructs a cluster array associated with \a C and a given
	//! size (for static use).
	/**
	 * @param C is the associated cluster graph.
	 * @param x is the default value for all array elements.
	 * @param size is the size of the array.
	 */
	ClusterArray(const ClusterGraph &C, const T &x, int size) :
		Array<T>(0,size-1,x),
		ClusterArrayBase(&C), m_x(x) { }

	//! Constructs a cluster array that is a copy of \a A.
	/**
	 * Associates the array with the same cluster graph as \a A and copies all elements.
	 */
	ClusterArray(const ClusterArray<T> &A) :
		Array<T>(A),
		ClusterArrayBase(A.m_pClusterGraph), m_x(A.m_x) { }

	//! Returns true iff the array is associated with a graph.
	bool valid() const { return (Array<T>::low() <= Array<T>::high()); }

	//! Returns a pointer to the associated cluster graph.
	const ClusterGraph *graphOf() const {
		return m_pClusterGraph;
	}

	//! Returns a reference to the element with index \a c.
	const T &operator[](cluster c) const {
		OGDF_ASSERT(c != 0 && c->graphOf() == m_pClusterGraph)
		return Array<T>::operator [](c->index());
	}

	//! Returns a reference to the element with index \a c.
	T &operator[](cluster c) {
		OGDF_ASSERT(c != 0 && c->graphOf() == m_pClusterGraph)
		return Array<T>::operator [](c->index());
	}

	//! Returns a reference to the element with index \a index.
	/**
	 * \attention Make sure that \a index is a valid index for a cluster
	 * in the associated cluster graph!
	 */
	const T &operator[](int index) const {
		return Array<T>::operator [](index);
	}

	//! Returns a reference to the element with index \a index.
	/**
	 * \attention Make sure that \a index is a valid index for a cluster
	 * in the associated cluster graph!
	 */
	T &operator[](int index) {
		return Array<T>::operator [](index);
	}

	//! Assignment operator.
	ClusterArray<T> &operator=(const ClusterArray<T> &a) {
		Array<T>::operator =(a);
		m_x = a.m_x;
		reregister(a.m_pClusterGraph);
		return *this;
	}

	//! Reinitializes the array. Associates the array with no cluster graph.
	void init() {
		Array<T>::init(); reregister(0);
	}

	//! Reinitializes the array. Associates the array with \a C.
	void init(const ClusterGraph &C) {
		Array<T>::init( C.clusterArrayTableSize() ); reregister(&C);
	}

	//! Reinitializes the array. Associates the array with \a C.
	/**
	 * @param C is the associated cluster graph.
	 * @param x is the default value.
	 */
	void init(const ClusterGraph &C, const T &x) {
		Array<T>::init(0,C.clusterArrayTableSize()-1, m_x = x); reregister(&C);
	}

	//! Sets all array elements to \a x.
	void fill(const T &x) {
		int high = m_pClusterGraph->maxClusterIndex();
		if(high >= 0)
			Array<T>::fill(0,high,x);
	}

private:
	virtual void enlargeTable(int newTableSize) {
		Array<T>::grow(newTableSize-Array<T>::size(),m_x);
	}

	virtual void reinit(int initTableSize) {
		Array<T>::init(0,initTableSize-1,m_x);
	}

	virtual void disconnect() {
		Array<T>::init();
		m_pClusterGraph = 0;
	}

	OGDF_NEW_DELETE

}; // class ClusterArray<T>


} // end namespace ogdf


#endif