/*******************************************************************************
 * Copyright (c) 2014, 2019 SAP SE 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:
 *     SAP SE - initial API and implementation
 *     Paul Pazderski - Bug 546900: Tests to check initial console content and content persistence
 *     Paul Pazderski - Bug 343023: Tests for 'clear initial content on first edit'
 *******************************************************************************/
package org.eclipse.jdt.debug.tests.console;

import static org.junit.Assert.assertArrayEquals;

import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

import org.eclipse.core.runtime.jobs.Job;
import org.eclipse.jdt.debug.tests.AbstractDebugTest;
import org.eclipse.jdt.debug.tests.TestUtil;
import org.eclipse.jdt.debug.ui.console.JavaStackTraceConsoleFactory;
import org.eclipse.jdt.internal.debug.ui.console.ConsoleMessages;
import org.eclipse.jdt.internal.debug.ui.console.JavaStackTraceConsole;
import org.eclipse.jdt.internal.debug.ui.console.JavaStackTraceConsolePage;
import org.eclipse.jface.text.BadLocationException;
import org.eclipse.jface.text.BadPositionCategoryException;
import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.Position;
import org.eclipse.swt.SWT;
import org.eclipse.swt.custom.ST;
import org.eclipse.swt.custom.StyledText;
import org.eclipse.swt.widgets.Event;
import org.eclipse.ui.IViewPart;
import org.eclipse.ui.IViewReference;
import org.eclipse.ui.IWorkbenchPage;
import org.eclipse.ui.IWorkbenchWindow;
import org.eclipse.ui.PlatformUI;
import org.eclipse.ui.console.ConsolePlugin;
import org.eclipse.ui.console.IConsole;
import org.eclipse.ui.console.IConsoleManager;
import org.eclipse.ui.console.TextConsoleViewer;
import org.eclipse.ui.internal.console.ConsoleHyperlinkPosition;
import org.eclipse.ui.internal.console.ConsoleView;

/**
 * Tests {@link JavaStackTraceConsole}
 */
public class JavaStackTraceConsoleTest extends AbstractDebugTest {

	private final JavaStackTraceConsoleFactory fConsoleFactory = new JavaStackTraceConsoleFactory();
	private JavaStackTraceConsole fConsole;

	public JavaStackTraceConsoleTest(String name) {
		super(name);
	}

	@Override
	public void setUp() throws Exception {
		super.setUp();
		initConsole(true);
	}

	@Override
	protected void tearDown() throws Exception {
		removeConsole(false);
		super.tearDown();
	}

	/**
	 * Create and register a {@link JavaStackTraceConsole}.
	 *
	 * @param assertDefaultContent
	 *            If <code>true</code> assert console is initialized with its default content.
	 * @see #removeConsole(boolean)
	 */
	private void initConsole(boolean assertDefaultContent) {
		fConsoleFactory.openConsole();
		IConsoleManager consoleManager = ConsolePlugin.getDefault().getConsoleManager();
		IConsole[] consoles = consoleManager.getConsoles();
		fConsole = null;
		for (IConsole console : consoles) {
			if (console instanceof JavaStackTraceConsole) {
				fConsole = (JavaStackTraceConsole) console;
				// do not end loop. There should be only one JavaStackTraceConsole but if there are more
				// the last one is most likely the one we opened
			}
		}
		assertNotNull("Failed to open a JavaStackTraceConsole", fConsole);
		if (assertDefaultContent) {
			assertInitialContent();
		}
	}

	/**
	 * Remove the previous created console.
	 *
	 * @param preserveContent
	 *            If <code>true</code> the remove does not prevent the current console content from being loaded by next
	 *            {@link JavaStackTraceConsole}.
	 * @see #initConsole(boolean)
	 */
	private void removeConsole(boolean preserveContent) {
		if (!preserveContent) {
			fConsole.clearConsole();
		}
		final int contentLength = fConsole.getDocument().getLength();

		IConsoleManager consoleManager = ConsolePlugin.getDefault().getConsoleManager();
		consoleManager.removeConsoles(new IConsole[] { fConsole });

		final Path stackTraceFile = Paths.get(JavaStackTraceConsole.FILE_NAME);
		if (!preserveContent) {
			assertTrue("Leaked content of JavaStackTraceConsole", Files.notExists(stackTraceFile));
		} else {
			assertTrue("JavaStackTraceConsole content was not persisted", Files.exists(stackTraceFile));
			try {
				assertTrue("Persisted content seems incomplete", Files.size(stackTraceFile) >= contentLength);
			} catch (IOException e) {
				fail("Persisted content seems incomplete");
			}
		}
	}

	public void testHyperlinkMatchSignatureSimple() throws Exception {
		consoleDocumentWithText("at foo.bar.Type.method1(Type.java:1)");

		String[] matchTexts = linkTextsAtPositions(24);
		assertArrayEquals(allLinks(), new String[] { "Type.java:1" }, matchTexts);
	}

	public void testHyperlinkMatchSignatureExtended() throws Exception {
		consoleDocumentWithText("at foo.bar.Type.method1(IILjava/lang/String;)V(Type.java:1)");

		String[] matchTexts = linkTextsAtPositions(47);
		assertArrayEquals(allLinks(), new String[] { "Type.java:1" }, matchTexts);
	}

	public void testHyperlinkMatchMultiple() throws Exception {
		consoleDocumentWithText("at foo.bar.Type.method2(Type.java:2)\n" //
				+ "at foo.bar.Type.method1(Type.java:1)");

		String[] matchTexts = linkTextsAtPositions(24, 61);
		assertArrayEquals(allLinks(), new String[] { "Type.java:2", "Type.java:1" }, matchTexts);
	}

	public void testHyperlinkMatchInvalidLine() throws Exception {
		consoleDocumentWithText("at foo.bar.Type.method1(Type.java:fff)");

		String[] matchTexts = linkTextsAtPositions(24);
		assertArrayEquals(allLinks(), new String[] { "Type.java:fff" }, matchTexts);
	}

	public void testHyperlinkNoMatch() throws Exception {
		consoleDocumentWithText("at foo.bar.Type.method1(foo.bar.Type.java:42)");

		Position[] positions = allLinkPositions();
		assertArrayEquals("Expected no hyperlinks for invalid type name", new Position[0], positions);
	}

	/**
	 * Test save/restore of stack trace console content on console close/reactivation.
	 */
	public void testLoadAndSaveDocument() throws Exception {
		IDocument initialDocument = fConsole.getDocument();
		String storedContent = "at foo.bar.Type.method1(Type.java:fff)";
		consoleDocumentWithText(storedContent);
		removeConsole(true);

		Path file = Paths.get(JavaStackTraceConsole.FILE_NAME);
		assertTrue("Content was not stored.", Files.exists(file));
		assertTrue("Content was not stored.", Files.size(file) > 0);

		initConsole(false);
		assertNotSame("Failed to create new console.", initialDocument, fConsole.getDocument());
		assertEquals("Failed to restore previous content.", storedContent, fConsole.getDocument().get());
	}

	/**
	 * Test for Bug 343023. Test if initial content is cleared on first edit and not cleared if it was changed programmatically before.
	 */
	public void testClearInitialContent() {
		PlatformUI.getWorkbench().getDisplay().syncExec(() -> {
			// type at start of initial content
			TextConsoleViewer viewer = getConsolesViewer();
			viewer.getTextWidget().invokeAction(ST.TEXT_START);
			doKeyStroke(viewer.getTextWidget(), 'a');
			assertEquals("Initial content was not cleared.", "a", fConsole.getDocument().get());
			doKeyStroke(viewer.getTextWidget(), 'b');
			assertEquals("Content was cleared again.", "ab", fConsole.getDocument().get());
			removeConsole(false);

			// type inside initial content
			initConsole(true);
			viewer = getConsolesViewer();
			viewer.getTextWidget().setCaretOffset(5);
			doKeyStroke(viewer.getTextWidget(), 'a');
			assertEquals("Initial content was not cleared.", "a", fConsole.getDocument().get());
			doKeyStroke(viewer.getTextWidget(), 'b');
			assertEquals("Content was cleared again.", "ab", fConsole.getDocument().get());
			removeConsole(false);

			// type at end of initial content
			initConsole(true);
			viewer = getConsolesViewer();
			viewer.getTextWidget().invokeAction(ST.TEXT_END);
			doKeyStroke(viewer.getTextWidget(), 'a');
			assertEquals("Initial content was not cleared.", "a", fConsole.getDocument().get());
			doKeyStroke(viewer.getTextWidget(), 'b');
			assertEquals("Content was cleared again.", "ab", fConsole.getDocument().get());
			removeConsole(false);

			// select all initial content
			initConsole(true);
			viewer = getConsolesViewer();
			viewer.getTextWidget().selectAll();
			doKeyStroke(viewer.getTextWidget(), 'a');
			assertEquals("Initial content was not cleared.", "a", fConsole.getDocument().get());
			doKeyStroke(viewer.getTextWidget(), 'b');
			assertEquals("Content was cleared again.", "ab", fConsole.getDocument().get());
			removeConsole(false);

			// select part of initial content
			initConsole(true);
			viewer = getConsolesViewer();
			viewer.getTextWidget().setSelection(5, 10);
			doKeyStroke(viewer.getTextWidget(), 'a');
			assertEquals("Initial content was not cleared.", "a", fConsole.getDocument().get());
			doKeyStroke(viewer.getTextWidget(), 'b');
			assertEquals("Content was cleared again.", "ab", fConsole.getDocument().get());
			removeConsole(false);

			// paste inside initial content
			initConsole(true);
			viewer = getConsolesViewer();
			viewer.getTextWidget().setCaretOffset(5);
			viewer.getTextWidget().insert("at foo.bar.Type.method1(IILjava/lang/String;)V(Type.java:1)");
			assertEquals("Initial content was not cleared.", "at foo.bar.Type.method1(IILjava/lang/String;)V(Type.java:1)", fConsole.getDocument().get());
			doKeyStroke(viewer.getTextWidget(), 'b');
			assertTrue("Content was cleared again.", fConsole.getDocument().getLength() > 5);
			removeConsole(false);

			// user edit after something already modified the content (expect no magic clear)
			initConsole(true);
			viewer = getConsolesViewer();
			String text = "Text set programmatically";
			viewer.getTextWidget().setText(text);
			viewer.getTextWidget().invokeAction(ST.TEXT_END);
			doKeyStroke(viewer.getTextWidget(), '!');
			assertEquals(text + "!", fConsole.getDocument().get());
			removeConsole(true); // preserve content this time!

			// check first edit does not clear if console is initialized with custom content
			initConsole(false);
			viewer = getConsolesViewer();
			int lengthBefore = fConsole.getDocument().getLength();
			doKeyStroke(viewer.getTextWidget(), 'a');
			assertEquals("Custom content was cleared.", lengthBefore + 1, fConsole.getDocument().getLength());
			// do not remove last console so tearDown can do something
		});
	}

	private IDocument consoleDocumentWithText(String text) throws InterruptedException {
		IDocument document = fConsole.getDocument();
		document.set(text);
		// wait for document being parsed and hyperlinks created
		Job.getJobManager().join(fConsole, null);
		return document;
	}

	private String[] linkTextsAtPositions(int... offsets) throws BadLocationException {
		IDocument document = fConsole.getDocument();

		List<String> texts = new ArrayList<>(offsets.length);
		List<Position> positions = linkPositions(offsets);
		for (Position pos : positions) {
			String matchText = document.get(pos.getOffset(), pos.getLength());
			texts.add(matchText);
		}
		return texts.toArray(new String[texts.size()]);
	}

	private List<Position> linkPositions(int... offsets) {
		List<Position> filteredPositions = new ArrayList<>(offsets.length);
		for (Position position : allLinkPositions()) {
			for (int offset : offsets) {
				if (offset >= position.getOffset() && offset <= (position.getOffset() + position.getLength())) {
					filteredPositions.add(position);
					break;
				}
			}
		}
		return filteredPositions;
	}

	private Position[] allLinkPositions() {
		try {
			return fConsole.getDocument().getPositions(ConsoleHyperlinkPosition.HYPER_LINK_CATEGORY);
		} catch (BadPositionCategoryException ex) {
			// no hyperlinks
		}
		return new Position[0];
	}

	private String allLinks() {
		return Arrays.toString(allLinkPositions());
	}

	/**
	 * Check if initial content is shown.
	 */
	public void assertInitialContent() {
		assertEquals("Console not loaded with initial content.", ConsoleMessages.JavaStackTraceConsole_0, fConsole.getDocument().get());
	}

	/**
	 * Tries to get the viewer of the currently tested console.
	 *
	 * @return the consoles viewer
	 */
	private TextConsoleViewer getConsolesViewer() {
		TestUtil.waitForJobs(getName(), 100, DEFAULT_TIMEOUT);
		IWorkbenchWindow workbenchWindow = PlatformUI.getWorkbench().getActiveWorkbenchWindow();
		assertNotNull(workbenchWindow);
		IWorkbenchPage activePage = workbenchWindow.getActivePage();
		assertNotNull(activePage);
		JavaStackTraceConsolePage page = null;
		for (IViewReference vref : activePage.getViewReferences()) {
			IViewPart view = vref.getView(false);
			if (view instanceof ConsoleView) {
				ConsoleView consoleView = (ConsoleView) view;
				if (consoleView.getConsole() == fConsole && consoleView.getCurrentPage() instanceof JavaStackTraceConsolePage) {
					page = (JavaStackTraceConsolePage) consoleView.getCurrentPage();
					break;
				}
			}
		}
		assertNotNull(page);
		return page.getViewer();
	}

	/**
	 * Simulate user pressing a key.
	 *
	 * @param widget
	 *            widget to type in
	 * @param c
	 *            character to type
	 */
	private void doKeyStroke(StyledText widget, char c) {
		final Event e = new Event();
		e.character = c;
		widget.notifyListeners(SWT.KeyDown, e);
		widget.notifyListeners(SWT.KeyUp, e);
	}
}