/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.commons.math4.geometry.euclidean.twod;

import org.junit.Assert;
import org.junit.Test;

import java.lang.reflect.Field;
import java.util.Arrays;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

public class NestedLoopsTest {

    private static final double EPS = Math.ulp(1d);

    @Test
    public void testNestedLoops() throws Exception {
        Cartesian2D oneOne = new Cartesian2D(1.0, 1.0);
        Cartesian2D oneNegativeOne = new Cartesian2D(1.0, -1.0);
        Cartesian2D negativeOneNegativeOne = new Cartesian2D(-1.0, -1.0);
        Cartesian2D negativeOneOne = new Cartesian2D(-1.0, 1.0);
        Cartesian2D origin = new Cartesian2D(0, 0);

        Cartesian2D [] vertices = new Cartesian2D[]{
                oneOne,
                oneNegativeOne,
                negativeOneNegativeOne,
                negativeOneOne,
                origin
        };

        NestedLoops nestedLoops = new NestedLoops(0.00000001);
        nestedLoops.add(vertices);
        nestedLoops.correctOrientation();

        Field surroundedField = nestedLoops.getClass().getDeclaredField("surrounded");
        Field loopField = nestedLoops.getClass().getDeclaredField("loop");
        surroundedField.setAccessible(Boolean.TRUE);
        loopField.setAccessible(Boolean.TRUE);
        List<NestedLoops> surrounded = (List<NestedLoops>) surroundedField.get(nestedLoops);
        Cartesian2D[] loop = (Cartesian2D []) loopField.get(surrounded.get(0));
        Set<Cartesian2D> vertexSet = new HashSet<>(Arrays.asList(loop));
        Assert.assertTrue(vertexSet.contains(oneOne));
        Assert.assertTrue(vertexSet.contains(oneNegativeOne));
        Assert.assertTrue(vertexSet.contains(negativeOneNegativeOne));
        Assert.assertTrue(vertexSet.contains(negativeOneOne));
        Assert.assertTrue(vertexSet.contains(origin));
    }

}