/**********************************************************************
 * $Id: Node.h 1820 2006-09-06 16:54:23Z mloskot $
 *
 * GEOS - Geometry Engine Open Source
 * http://geos.refractions.net
 *
 * Copyright (C) 2005-2006 Refractions Research Inc.
 * Copyright (C) 2001-2002 Vivid Solutions Inc.
 *
 * This is free software; you can redistribute and/or modify it under
 * the terms of the GNU Lesser General Public Licence as published
 * by the Free Software Foundation. 
 * See the COPYING file for more information.
 *
 **********************************************************************
 *
 * Last port: geomgraph/Node.java rev. 1.6 (JTS-1.7)
 *
 **********************************************************************/


#ifndef GEOS_GEOMGRAPH_NODE_H
#define GEOS_GEOMGRAPH_NODE_H

#include <geos/geomgraph/GraphComponent.h> // for inheritance
#include <geos/geom/Coordinate.h> // for member

#ifndef NDEBUG
#include <geos/geomgraph/EdgeEndStar.h> // for testInvariant
#include <geos/geomgraph/EdgeEnd.h> // for testInvariant
#endif // ndef NDEBUG

#include <geos/inline.h>

#include <cassert>
#include <string>

// Forward declarations
namespace geos {
	namespace geom {
		class IntersectionMatrix;
	}
	namespace geomgraph {
		class Node;
		class EdgeEndStar;
		class EdgeEnd;
		class Label;
		class NodeFactory;
	}
}

namespace geos {
namespace geomgraph { // geos.geomgraph

class Node: public GraphComponent {
using GraphComponent::setLabel;

public:

	friend std::ostream& operator<< (std::ostream& os, const Node& node);

	Node(const geom::Coordinate& newCoord, EdgeEndStar* newEdges);

	virtual ~Node();

	virtual const geom::Coordinate& getCoordinate() const;

	virtual EdgeEndStar* getEdges();

	virtual bool isIsolated() const;

	/** \brief
	 * Add the edge to the list of edges at this node
	 */
	virtual void add(EdgeEnd *e);

	virtual void mergeLabel(const Node& n);

	/** \brief
	 * To merge labels for two nodes,
	 * the merged location for each LabelElement is computed.
	 *
	 * The location for the corresponding node LabelElement is set
	 * to the result, as long as the location is non-null.
	 */
	virtual void mergeLabel(const Label& label2);

	virtual void setLabel(int argIndex, int onLocation);

	/** \brief
	 * Updates the label of a node to BOUNDARY,
	 * obeying the mod-2 boundaryDetermination rule.
	 */
	virtual void setLabelBoundary(int argIndex);

	/**
	 * The location for a given eltIndex for a node will be one
	 * of { null, INTERIOR, BOUNDARY }.
	 * A node may be on both the boundary and the interior of a geometry;
	 * in this case, the rule is that the node is considered to be
	 * in the boundary.
	 * The merged location is the maximum of the two input values.
	 */
	virtual int computeMergedLocation(const Label* label2, int eltIndex);

	virtual std::string print();

	virtual const std::vector<double> &getZ() const;

	virtual void addZ(double);

	/** \brief
	 * Tests whether any incident edge is flagged as
	 * being in the result.
	 *
	 * This test can be used to determine if the node is in the result,
	 * since if any incident edge is in the result, the node must be in
	 * the result as well.
	 *
	 * @return <code>true</code> if any indicident edge in the in
	 *         the result
	 */
	virtual bool isIncidentEdgeInResult() const;

protected:

	void testInvariant() const;

	geom::Coordinate coord;

	EdgeEndStar* edges;

	/** \brief
	 * Basic nodes do not compute IMs
	 */
	virtual void computeIM(geom::IntersectionMatrix *im) {};

private:

	std::vector<double>zvals;

	double ztot;

};

std::ostream& operator<< (std::ostream& os, const Node& node);

inline void
Node::testInvariant() const
{
#ifndef NDEBUG
	if (edges)
	{
		// Each EdgeEnd in the star has this Node's 
		// coordinate as first coordinate
		for (EdgeEndStar::iterator
				it=edges->begin(), itEnd=edges->end();
				it != itEnd; it++) 
		{
			EdgeEnd* e=*it;
			assert(e);
			assert(e->getCoordinate().equals2D(coord));
		}
	}

#if 0 // We can't rely on numerical stability with FP computations
	// ztot is the sum of doubnle sin zvals vector
	double ztot_check=0.0;
	for (std::vector<double>::const_iterator 
			i = zvals.begin(), e = zvals.end();
			i != e;
			i++)
	{
		ztot_check += *i;
	}
	assert(ztot_check == ztot);
#endif // 0

#endif
}


} // namespace geos.geomgraph
} // namespace geos

//#ifdef GEOS_INLINE
//# include "geos/geomgraph/Node.inl"
//#endif

#endif // ifndef GEOS_GEOMGRAPH_NODE_H

/**********************************************************************
 * $Log$
 * Revision 1.6  2006/06/01 11:49:36  strk
 * Reduced installed headers form geomgraph namespace
 *
 * Revision 1.5  2006/04/27 15:15:06  strk
 * Z check removed from invariant tester to avoid aborts due to differences in FP computations.
 *
 * Revision 1.4  2006/04/07 16:01:51  strk
 * Port info, doxygen comments, testInvariant(), many assertionss, handling of
 * the NULL EdgeEndStar member
 *
 * Revision 1.3  2006/03/24 09:52:41  strk
 * USE_INLINE => GEOS_INLINE
 *
 * Revision 1.2  2006/03/15 16:27:54  strk
 * operator<< for Node class
 *
 * Revision 1.1  2006/03/09 16:46:49  strk
 * geos::geom namespace definition, first pass at headers split
 *
 **********************************************************************/