poi/poi-ooxml/src/test/java/org/apache/poi/xdgf/usermodel/section/geometry/TestArcTo.java

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   this work for additional information regarding copyright ownership.
   The ASF licenses this file to You under the Apache License, Version 2.0
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package org.apache.poi.xdgf.usermodel.section.geometry;

import com.microsoft.schemas.office.visio.x2012.main.CellType;
import com.microsoft.schemas.office.visio.x2012.main.RowType;
import com.microsoft.schemas.office.visio.x2012.main.SectionType;
import com.microsoft.schemas.office.visio.x2012.main.TriggerType;

import org.apache.poi.util.LocaleUtil;
import org.apache.poi.xdgf.usermodel.section.GeometrySection;
import org.junit.jupiter.api.Assertions;
import org.junit.jupiter.api.Test;

import java.awt.geom.Path2D;
import java.awt.geom.PathIterator;
import java.util.Arrays;

import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertNotNull;
import static org.junit.jupiter.api.Assertions.assertNull;
import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.when;

public class TestArcTo {

    private static final double EPS = 0.000001;

    // We draw a circular arc with radius 100 from (0, 0) to (100, 100)
    private static final double X0 = 0.0;
    private static final double Y0 = 0.0;
    private static final double X = 100.0;
    private static final double Y = 100.0;
    private static final double A = 29.289322; // a = radius - sqrt(((x + x0) / 2) ^ 2 + ((y + y0) / 2) ^2)

    @Test
    public void shouldDrawCircularArcWhenArcHeightMoreThanZero() {
        ArcTo arcTo = createArcTo(A);

        Path2D.Double actualPath = new Path2D.Double();
        actualPath.moveTo(X0, Y0);

        // Shape isn't used while creating a circular arc
        arcTo.addToPath(actualPath, null);

        // This path can be used to draw a curve that approximates calculated arc.
        Path2D.Double expectedPath = new Path2D.Double();
        expectedPath.moveTo(X0, Y0);
        expectedPath.curveTo(26.521649, 0.0, 51.957040, 10.535684, 70.710678, 29.289321);
        expectedPath.curveTo(89.464316, 48.042960, 100.000000, 73.478351, X, Y);

        assertPath(expectedPath, actualPath);
    }

    @Test
    public void shouldDrawCircularArcWhenArcHeightLessThanZero() {
        ArcTo arcTo = createArcTo(-A);

        Path2D.Double actualPath = new Path2D.Double();
        actualPath.moveTo(X0, Y0);

        // Shape isn't used while creating a circular arc
        arcTo.addToPath(actualPath, null);

        // This path can be used to draw a curve that approximates calculated arc.
        Path2D.Double expectedPath = new Path2D.Double();
        expectedPath.moveTo(X0, Y0);
        expectedPath.curveTo(0.0, 26.521649, 10.535684, 51.957040, 29.289321, 70.710678);
        expectedPath.curveTo(48.042960, 89.464316,  73.478351, 100.000000,  X, Y);

        assertPath(expectedPath, actualPath);
    }

    @Test
    public void shouldDrawLineInsteadOfArcWhenArcHeightIsZero() {
        ArcTo arcTo = createArcTo(0.0);

        Path2D.Double actualPath = new Path2D.Double();
        actualPath.moveTo(X0, Y0);

        // Shape isn't used while creating a circular arc
        arcTo.addToPath(actualPath, null);

        // This path can be used to draw a curve that approximates calculated arc.
        Path2D.Double expectedPath = new Path2D.Double();
        expectedPath.moveTo(X0, Y0);
        expectedPath.lineTo(X, Y);

        assertPath(expectedPath, actualPath);
    }

    @Test
    public void shouldNotDrawAnythingWhenArcIsDeleted() {
        RowType row = RowType.Factory.newInstance();
        row.setIX(0L);
        row.setDel(true);

        ArcTo arcTo = new ArcTo(row);

        Path2D.Double actualPath = new Path2D.Double();
        actualPath.moveTo(X0, Y0);

        // Shape isn't used while creating a circular arc
        arcTo.addToPath(actualPath, null);

        // This path can be used to draw a curve that approximates calculated arc.
        Path2D.Double expectedPath = new Path2D.Double();
        expectedPath.moveTo(X0, Y0);

        assertPath(expectedPath, actualPath);
    }

    // this test is mostly used to trigger inclusion of some
    // classes into poi-ooxml-lite
    @Test
    public void testSnapshot() {
        SectionType sectionType = mock(SectionType.class);
        RowType rowType = mock(RowType.class);

        when(sectionType.getCellArray()).thenReturn(new CellType[0]);
        when(sectionType.getRowArray()).thenReturn(new RowType[] {
                rowType
        });
        when(rowType.getIX()).thenReturn(0L);
        when(rowType.getT()).thenReturn("ArcTo");
        when(rowType.getCellArray()).thenReturn(new CellType[0]);

        GeometrySection section = new GeometrySection(sectionType, null);
        assertNotNull(section);

        TriggerType[] triggerArray = sectionType.getTriggerArray();
        assertNull(triggerArray);
    }

    private static ArcTo createArcTo(double a) {
        RowType row = RowType.Factory.newInstance();
        row.setIX(0L);
        row.setDel(false);

        CellType xCell = CellType.Factory.newInstance();
        xCell.setN("X");
        xCell.setV(Double.toString(X));

        CellType yCell = CellType.Factory.newInstance();
        yCell.setN("Y");
        yCell.setV(Double.toString(Y));


        CellType aCell = CellType.Factory.newInstance();
        aCell.setN("A");
        aCell.setV(Double.toString(a));

        CellType[] cells = new CellType[] { xCell , yCell, aCell };
        row.setCellArray(cells);

        return new ArcTo(row);
    }

    private static void assertPath(Path2D expected, Path2D actual) {
        PathIterator expectedIterator = expected.getPathIterator(null);
        PathIterator actualIterator = actual.getPathIterator(null);

        double[] expectedCoordinates = new double[6];
        double[] actualCoordinates = new double[6];
        while (!expectedIterator.isDone() && !actualIterator.isDone()) {
            int expectedSegmentType = expectedIterator.currentSegment(expectedCoordinates);
            int actualSegmentType = actualIterator.currentSegment(actualCoordinates);

            assertEquals(expectedSegmentType, actualSegmentType);
            assertCoordinates(expectedCoordinates, actualCoordinates);

            expectedIterator.next();
            actualIterator.next();
        }

        if (!expectedIterator.isDone() || !actualIterator.isDone()) {
            Assertions.fail("Path iterators have different number of segments");
        }
    }

    private static void assertCoordinates(double[] expected, double[] actual) {
        if (expected.length != actual.length) {
            Assertions.fail(String.format(
                    LocaleUtil.getUserLocale(),
                    "Given coordinates arrays have different length: expected=%s, actual=%s",
                    Arrays.toString(expected), Arrays.toString(actual)));
        }
        for (int i = 0; i < expected.length; i++) {
            double e = expected[i];
            double a = actual[i];

            if (Math.abs(e - a) > EPS) {
                Assertions.fail(String.format(
                        LocaleUtil.getUserLocale(),
                        "expected <%f> but found <%f>", e, a));
            }
        }
    }
}