//
//RTree implementation.
//Copyright (C) 2002-2004 Wolfgang Baer - WBaer@gmx.de
//
//This library is free software; you can redistribute it and/or
//modify it under the terms of the GNU Lesser General Public
//License as published by the Free Software Foundation; either
//version 2.1 of the License, or (at your option) any later version.
//
//This library 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
//Lesser General Public License for more details.
//
//You should have received a copy of the GNU Lesser General Public
//License along with this library; if not, write to the Free Software
//Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

package org.deegree.io.rtree;

import java.io.Serializable;

/**
 * <p>
 * Abstract class for common implementation and definition of abstract methods
 * for both concrete classes LeafNode and NoneLeafNode.
 * </p>
 * @author Wolfgang Baer - WBaer@gmx.de
 */

abstract class Node implements Serializable {

    protected transient PageFile file;

	protected int parentNode;
	protected int pageNumber;
	protected int counter;
    protected HyperBoundingBox unionMinBB;
    protected HyperBoundingBox[] hyperBBs;

    protected int place;

    /**
	 * Constructor.
	 * @param pageNumber - number of this node in page file
	 * @param file - the PageFile of this node
     */
    protected Node( int pageNumber, PageFile pageFile ) {
        this.file = pageFile;
        this.pageNumber = pageNumber;
        parentNode = 0;
        hyperBBs = new HyperBoundingBox[file.getCapacity()];

        for ( int i = 0; i < file.getCapacity(); i++ )
            hyperBBs[i] = HyperBoundingBox.getNullHyperBoundingBox( file.getDimension() );

        unionMinBB = HyperBoundingBox.getNullHyperBoundingBox( file.getDimension() );
        counter = 0;
    }

    /**
	 * Inserts the given data into the node
	 * @param obj - object to insert (Typ Integer oder AbstractNode)
	 * @param box - the associated HyperBoundingBox
     */
	protected abstract void insertData(Object obj, HyperBoundingBox box); 

	/** 
	 * Deletes a the entry with given index from node
	 * @param index - index of entry
     */
	protected abstract void deleteData(int index);				

    /**
	 * Fetches the data for given index from node
	 * @param index - index of data
     */
	protected abstract Object getData( int index );

    /**
	 * Returns the parent node of this.
	 * @return Node
     */
    protected Node getParent() {

		Node node = null;		
        try {
            node = file.readNode( parentNode );
        } catch ( PageFileException e ) {
            //PageFileException: AbstractNode.getParent() - readNode
            e.printStackTrace();
        }

        return node;
    }

    /**
     * Returns the page number of this.
     * @return int
     */
    protected int getPageNumber() {
        return pageNumber;
    }

    /**
     * Sets the page number of this to given number
     * @param number - int
     */
    protected void setPageNumber(int number) {
        this.pageNumber = number;
    }


    /**
	 * Currently used space in the node
	 * @return int
     */
	protected int getUsedSpace() {
        return counter;
    }

    /**
     * Returns the HyperBoundingBox over all Entries currently in the node
     * @return HyperBoundingBox
     */
    protected HyperBoundingBox getUnionMinBB() {
        return unionMinBB;
    }

    /**
	 * Updates the HyperBoundingBox over all Entries currently in the node
     */
    protected void updateNodeBoundingBox() {
		this.unionMinBB = HyperBoundingBox.getNullHyperBoundingBox(file.getDimension());;
        for ( int i = 0; i < this.getUsedSpace(); i++ )
            this.unionMinBB = this.unionMinBB.unionBoundingBox( this.hyperBBs[i] );
    }

    /**
	 * Returns an array of HyperBoundingBox objects of the entries of the node.
	 * The array may be empty - for used place in the node see getUsedSpace.
	 * @return HyperBoundingBox[] - boxes of the entries
     * @see #getUsedSpace()
     */
    protected HyperBoundingBox[] getHyperBoundingBoxes() {
        return hyperBBs;
    }

    /**
     * Returns the HyperBoundingBox for entrie with given index.
	 * @param index - index of entry
	 * @return HyperBoundingBox
     */
    protected HyperBoundingBox getHyperBoundingBox( int index ) {
        return hyperBBs[index];
    }

    /**
     * Tests if this is the root node.
	 * @return boolean
     */
    protected boolean isRoot() {
        return pageNumber == 0;
    }

    /**
     * Deep copy without data entries (only HyperBoundingBox objects)
     * @see java.lang.Object#clone()
     */
    protected abstract Object clone();

    /**
     * String-Representation of Node
     */
    public String toString() {
        String str = "";

        if ( this instanceof LeafNode ) {
            str = "LeafNode: " + unionMinBB.toString();
        } else {
            str = "NoneLeafNode: " + unionMinBB.toString();
        }

        return str;
    }
}/* ********************************************************************
Changes to this class. What the people have been up to:
$Log: Node.java,v $
Revision 1.5  2006/07/12 14:46:17  poth
comment footer added

********************************************************************** */