/*
 * The JTS Topology Suite is a collection of Java classes that
 * implement the fundamental operations required to validate a given
 * geo-spatial data set to a known topological specification.
 *
 * Copyright (C) 2001 Vivid Solutions
 *
 * 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
 *
 * For more information, contact:
 *
 *     Vivid Solutions
 *     Suite #1A
 *     2328 Government Street
 *     Victoria BC  V8T 5G5
 *     Canada
 *
 *     (250)385-6040
 *     www.vividsolutions.com
 */
package com.vividsolutions.jts.geom.prep;

import java.util.List;

import com.vividsolutions.jts.geom.Geometry;
import com.vividsolutions.jts.noding.SegmentStringUtil;

/**
 * Computes the <tt>intersects</tt> spatial relationship predicate
 * for {@link PreparedPolygon}s relative to all other {@link Geometry} classes.
 * Uses short-circuit tests and indexing to improve performance. 
 * 
 * @author Martin Davis
 *
 */
class PreparedPolygonIntersects 
	extends PreparedPolygonPredicate
{
	/**
	 * Computes the intersects predicate between a {@link PreparedPolygon}
	 * and a {@link Geometry}.
	 * 
	 * @param prep the prepared polygon
	 * @param geom a test geometry
	 * @return true if the polygon intersects the geometry
	 */
	public static boolean intersects(PreparedPolygon prep, Geometry geom)
	{
    PreparedPolygonIntersects polyInt = new PreparedPolygonIntersects(prep);
    return polyInt.intersects(geom);
	}
	
  /**
   * Creates an instance of this operation.
   * 
   * @param prepPoly the PreparedPolygon to evaluate
   */
	public PreparedPolygonIntersects(PreparedPolygon prepPoly)
	{
		super(prepPoly);
	}
	
	/**
	 * Tests whether this PreparedPolygon intersects a given geometry.
	 * 
	 * @param geom the test geometry
	 * @return true if the test geometry intersects
	 */
	public boolean intersects(Geometry geom)
	{
		/**
		 * Do point-in-poly tests first, since they are cheaper and may result
		 * in a quick positive result.
		 * 
		 * If a point of any test components lie in target, result is true
		 */
		boolean isInPrepGeomArea = isAnyTestComponentInTarget(geom);
		if (isInPrepGeomArea) return true;
		
		/**
		 * If any segments intersect, result is true
		 */
    List lineSegStr = SegmentStringUtil.extractSegmentStrings(geom);
		boolean segsIntersect = prepPoly.getIntersectionFinder().intersects(lineSegStr);
		if (segsIntersect) 
      return true;
		
		/**
		 * If the test has dimension = 2 as well, it is necessary to
		 * test for proper inclusion of the target.
		 * Since no segments intersect, it is sufficient to test representative points.
		 */
		if (geom.getDimension() == 2) {
			// TODO: generalize this to handle GeometryCollections
			boolean isPrepGeomInArea = isAnyTargetComponentInAreaTest(geom, prepPoly.getRepresentativePoints());
			if (isPrepGeomInArea) return true;
		}
		
		return false;
	}
	  
}
