tests/org.eclipse.e4.ui.tests.css.swt/src/org/eclipse/e4/ui/tests/css/swt/GradientTest.java

/*******************************************************************************
 * Copyright (c) 2009, 2014 IBM Corporation and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *     Thibault Le Ouay <thibaultleouay@gmail.com> - Bug 443094
 *******************************************************************************/
package org.eclipse.e4.ui.tests.css.swt;

import static org.junit.Assert.assertArrayEquals;
import static org.junit.Assert.assertEquals;

import java.lang.reflect.Field;

import org.eclipse.swt.SWT;
import org.eclipse.swt.custom.CTabFolder;
import org.eclipse.swt.custom.CTabItem;
import org.eclipse.swt.graphics.Color;
import org.eclipse.swt.graphics.RGB;
import org.eclipse.swt.layout.FillLayout;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Shell;
import org.junit.Test;

/**
 * Test gradient capabilities.
 * We use CTabFolder because we can retrieve the gradient values from it.
 * Other usage of gradients is drawn by GradientBackgroundListener which is harder
 * to test it's doing the right thing.
 */

public class GradientTest extends CSSSWTTestCase {

	static final RGB RED = new RGB(255, 0, 0);
	static final RGB GREEN = new RGB(0, 255, 0);
	static final RGB BLUE = new RGB(0, 0, 255);
	static final RGB WHITE = new RGB(255, 255, 255);

	protected CTabFolder createTestCTabFolder(String styleSheet) {
		engine = createEngine(styleSheet, display);

		// Create widgets
		Shell shell = new Shell(display, SWT.SHELL_TRIM);
		FillLayout layout = new FillLayout();
		shell.setLayout(layout);
		Composite panel = new Composite(shell, SWT.NONE);
		panel.setLayout(new FillLayout());

		CTabFolder folderToTest = new CTabFolder(panel, SWT.NONE);
		CTabItem tab1 = new CTabItem(folderToTest, SWT.NONE);
		tab1.setText("A TAB ITEM");

		engine.applyStyles(folderToTest, true);

		shell.pack();
		return folderToTest;
	}

	@Test
	public void testGradients() {
		CTabFolder folderToTest = createTestCTabFolder(
				"CTabItem:selected { background-color: #FF0000 #0000FF}");
		assertEquals(RED, getSelectionBackgroundBegin(folderToTest).getRGB()); //gradient begin
		assertEquals(BLUE, folderToTest.getSelectionBackground().getRGB()); //gradient end
	}

	@Test
	public void testDefaultPercents() {
		CTabFolder folderToTest = createTestCTabFolder(
				"CTabItem:selected { background-color: #FF0000 #0000FF}");
		assertEquals(RED, getSelectionBackgroundBegin(folderToTest).getRGB()); //gradient begin
		assertEquals(BLUE, folderToTest.getSelectionBackground().getRGB()); //gradient end
		assertArrayEquals(new int[] { 100 }, getSelectionGradientPercents(folderToTest)); // default
		// percent
	}

	@Test
	public void testDefaultManyPercents() {
		CTabFolder folderToTest = createTestCTabFolder(
				"CTabItem:selected { background-color: red green blue yellow}");
		assertArrayEquals(new int[] { 33, 67, 100 }, getSelectionGradientPercents(folderToTest)); // default
		// percent
	}

	@Test
	public void testSpecifiedPercents() {
		CTabFolder folderToTest = createTestCTabFolder(
				"CTabItem:selected { background-color: #FF0000 #0000FF 53%}");
		assertArrayEquals(new int[] { 53 }, getSelectionGradientPercents(folderToTest));
	}

	@Test
	public void testManyColorsAndSpecifiedManyPercents() {
		CTabFolder folderToTest = createTestCTabFolder(
				"CTabItem:selected { background-color: #FF0000 #00FF00 #0000FF 22% 44%}");
		assertEquals(RED, getSelectionBackgroundBegin(folderToTest).getRGB()); //gradient begin
		assertEquals(GREEN, getSelectionBackground(folderToTest, 1).getRGB()); //2nd gradient
		assertEquals(BLUE, folderToTest.getSelectionBackground().getRGB()); //gradient end
		assertArrayEquals(new int[] { 22, 44 }, getSelectionGradientPercents(folderToTest));
	}

	/*
	 * Tests handling when # of percents isn't one less than number of colors
	 */
	@Test
	public void testBadPercents() {
		//There should be either zero or three percent declarations, otherwise it acts as default
		CTabFolder folderToTest = createTestCTabFolder(
				"CTabItem:selected { background-color: red green blue yellow 10%}");
		assertArrayEquals(new int[] { 33, 67, 100 }, getSelectionGradientPercents(folderToTest)); // default
		// percent
	}

	/*
	 * Test to ensure that one bad apple doesn't spoil it for everyone
	 * (non-existent color name is ignored)
	 */
	@Test
	public void testBadColors() {
		CTabFolder folderToTest = createTestCTabFolder(
				"CTabItem:selected { background-color: #FF0000 notAColor #0000FF}");
		assertEquals(RED, getSelectionBackgroundBegin(folderToTest).getRGB()); //gradient begin
		assertEquals(BLUE, folderToTest.getSelectionBackground().getRGB()); //gradient end
		assertArrayEquals(new int[] { 100 }, getSelectionGradientPercents(folderToTest)); // default
		// percent
	}

	/*
	 * Test to ensure that a percent > 100 triggers default
	 */
	@Test
	public void testAboveRangePercents() {
		CTabFolder folderToTest = createTestCTabFolder(
				"CTabItem:selected { background-color: #FF0000 #00FF00 #0000FF 20% 110%}");
		assertEquals(RED, getSelectionBackgroundBegin(folderToTest).getRGB()); //gradient begin
		assertEquals(BLUE, folderToTest.getSelectionBackground().getRGB()); //gradient end
		assertArrayEquals(new int[] { 50, 100 }, getSelectionGradientPercents(folderToTest)); // default
		// percent
	}

	/*
	 * Test to ensure that a percent < 0 triggers default
	 */
	@Test
	public void testBelowRangePercents() {
		CTabFolder folderToTest = createTestCTabFolder(
				"CTabItem:selected { background-color: #FF0000 #00FF00 #0000FF -20% 50%}");
		assertEquals(RED, getSelectionBackgroundBegin(folderToTest).getRGB()); //gradient begin
		assertEquals(BLUE, folderToTest.getSelectionBackground().getRGB()); //gradient end
		assertArrayEquals(new int[] { 50, 100 }, getSelectionGradientPercents(folderToTest)); // default
		// percent
	}

	/*
	 * Test to ensure we properly parse something like:
	 *    background-color: gradient,
	 *           rgb(140,140,140),
	 *           rgb(48,48,48),
	 *           100%;
	 */
	@Test
	public void testAltSyntax() {
		CTabFolder folderToTest = createTestCTabFolder(
				"CTabItem:selected { background-color: gradient, rgb(140,140,140), rgb(48,48,48), 100%;");
		assertEquals(new RGB(140,140,140), getSelectionBackgroundBegin(folderToTest).getRGB()); //gradient begin
		assertEquals(new RGB(48,48,48), folderToTest.getSelectionBackground().getRGB()); //gradient end
		assertArrayEquals(new int[] { 100 }, getSelectionGradientPercents(folderToTest)); // default
		// percent
	}



	//CTabFolder doesn't provide getter for these so we need to dig via reflection

	Color getSelectionBackgroundBegin(CTabFolder folder) {
		return getSelectionBackground(folder, 0);
	}

	Color getSelectionBackground(CTabFolder folder, int i) {
		try {
			Field field = folder.getClass().getDeclaredField("selectionGradientColors");
			field.setAccessible(true);
			return ((Color[]) field.get(folder))[i];
		} catch (NoSuchFieldException | IllegalAccessException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		return null;
	}

	int[] getSelectionGradientPercents(CTabFolder folder) {
		//CTabFolder doesn't provide a getter for this so we need to dig via reflection
		try {
			Field field = folder.getClass().getDeclaredField("selectionGradientPercents");
			field.setAccessible(true);
			return (int[]) field.get(folder);
		} catch (NoSuchFieldException | IllegalAccessException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		return null;
	}
}