/*
 *    GeoTools - The Open Source Java GIS Toolkit
 *    http://geotools.org
 * 
 *    (C) 2002-2008, Open Source Geospatial Foundation (OSGeo)
 *
 *    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;
 *    version 2.1 of the License.
 *
 *    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.
 */
package org.geotools.referencing.operation.builder;

import org.geotools.geometry.DirectPosition2D;
import org.opengis.geometry.DirectPosition;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Random;

import org.junit.*;
import static org.junit.Assert.*;


public final class TriangulationFactoryTest {
    /**
     * Test (@link TringulationFactory).
     */
    @Test
    public void testTringulationFactory() {
        DirectPosition sp1 = new DirectPosition2D(10, 10);
        DirectPosition tp1 = new DirectPosition2D(10, 10);

        DirectPosition sp2 = new DirectPosition2D(20, 10);
        DirectPosition tp2 = new DirectPosition2D(20, 10);

        DirectPosition sp3 = new DirectPosition2D(20, 20);
        DirectPosition tp3 = new DirectPosition2D(20, 20);

        DirectPosition sp4 = new DirectPosition2D(10, 20);
        DirectPosition tp4 = new DirectPosition2D(10, 20);

        DirectPosition sp5 = new DirectPosition2D(14, 16);
        DirectPosition tp5 = new DirectPosition2D(14, 16);

        ExtendedPosition mtp1 = new ExtendedPosition(sp1, tp1);
        ExtendedPosition mtp2 = new ExtendedPosition(sp2, tp2);
        ExtendedPosition mtp3 = new ExtendedPosition(sp3, tp3);
        ExtendedPosition mtp4 = new ExtendedPosition(sp4, tp4);
        ExtendedPosition mtp5 = new ExtendedPosition(sp5, tp5);
        DirectPosition[] vertices = new DirectPosition[1];
        vertices[0] = mtp5;

        Quadrilateral quad = new Quadrilateral(mtp1, mtp2, mtp3, mtp4);

        try {
            new TriangulationFactory(quad,
                    vertices);
        } catch (TriangulationException e) {
            System.out.println(e.getMessage());
        }
    }
    
    /**
     * Test (@link TriangulationFactory). Triangles are tested with delaunay test.
     */
    @Test
    public void testDelaunay() throws TriangulationException {
        // coordinates of quadrilateral for triangulation
        DirectPosition2D leftDown  = new DirectPosition2D(100, 100);
        DirectPosition2D rightDown = new DirectPosition2D(200, 100);
        DirectPosition2D rightTop  = new DirectPosition2D(200, 250);
        DirectPosition2D leftTop   = new DirectPosition2D(100, 250);

        // generator for points within the quadrilateral:
        Random randomCoord = new Random(872066443);

        // number of points
        int number = 5;
        DirectPosition[] vertices = new DirectPosition[number];

        for (int i = 0; i < number; i++) {
            double x = leftDown.x + (randomCoord.nextDouble() * (rightDown.x - leftDown.x));
            double y = leftDown.y + (randomCoord.nextDouble() * (leftTop  .y - leftDown.y));
            vertices[i] = new DirectPosition2D(x, y);
        }

        Quadrilateral quad = new Quadrilateral(leftDown, rightDown, rightTop, leftTop);

        List<TINTriangle> triangles = new ArrayList<TINTriangle>();

        TriangulationFactory trigfac = new TriangulationFactory(quad, vertices);
        triangles = trigfac.getTriangulation();

        int j = 1;

        for (Iterator<TINTriangle> i = triangles.iterator(); i.hasNext();) {
            TINTriangle triangle = i.next();

            for (j = 0; j < vertices.length; j++) {
                // Delunay Test - there are no vetrices in the CircumCicle
                assertFalse(triangle.getCircumCicle().contains(vertices[j]));
            }
        }
    }
}