plugins/org.eclipse.app4mc.amalthea.visualization.runnabledependency/src/org/eclipse/app4mc/amalthea/visualization/runnabledependency/RunnableDependencyVisualization.java

/**
 ********************************************************************************
 * Copyright (c) 2020-2022 DLR e. V. and OFFIS e. V. 
 * 
 * This program and the accompanying materials are made
 * available under the terms of the Eclipse Public License 2.0
 * which is available at https://www.eclipse.org/legal/epl-2.0/
 * 
 * SPDX-License-Identifier: EPL-2.0
 * 
 * Contributors:
 *     OFFIS e. V. - initial API and implementation
 *     DLR e. V.   - initial API and implementation
 *******************************************************************************/

package org.eclipse.app4mc.amalthea.visualization.runnabledependency;

import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.lang.ProcessBuilder.Redirect;
import java.nio.charset.StandardCharsets;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.function.Consumer;

import javax.annotation.PostConstruct;

import org.eclipse.app4mc.amalthea.model.SWModel;
import org.eclipse.app4mc.visualization.ui.registry.Visualization;
import org.eclipse.core.runtime.Platform;
import org.eclipse.e4.core.di.extensions.Preference;
import org.eclipse.e4.core.services.events.IEventBroker;
import org.eclipse.jface.dialogs.MessageDialog;
import org.eclipse.jface.layout.GridDataFactory;
import org.eclipse.jface.layout.GridLayoutFactory;
import org.eclipse.jface.layout.RowLayoutFactory;
import org.eclipse.swt.SWT;
import org.eclipse.swt.browser.Browser;
import org.eclipse.swt.browser.LocationListener;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.events.SelectionListener;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.FileDialog;
import org.eclipse.swt.widgets.Shell;
import org.osgi.service.component.annotations.Component;

import net.sourceforge.plantuml.eclipse.utils.PlantumlConstants;

@Component(property = {
		"name=Runnable Data Dependencies",
		"description=Runnable Label Access Visualization for Software Models"
})
public class RunnableDependencyVisualization implements Visualization {

	private static GraphvizGeneratorConfig config = new GraphvizGeneratorConfig();
	private GraphvizGenerator graphvizGenerator;
	private Browser browser;
	private String dotPath;
	private SWModel model;

	/**
	 * Entry point for the visualization framework
	 * 
	 * @param model   software model that shall be visualized
	 * @param parent  parent component
	 * @param dotPath path to Graphviz DOT executable
	 * @param broker  event broker for element selection
	 */
	@PostConstruct
	public void createVisualization(
			SWModel model,
			Composite parent,
			@Preference(
					nodePath = "net.sourceforge.plantuml.eclipse",
					value = PlantumlConstants.GRAPHVIZ_PATH)
			String dotPath,
			IEventBroker broker) {

		this.graphvizGenerator = new GraphvizGenerator(config, true, true);
		this.model = model;
		if (dotPath == null) {
			if (Platform.getOS().equals(Platform.OS_WIN32)) {
				this.dotPath = "dot.exe";
			} else {
				this.dotPath = "dot";
			}
		} else {
			this.dotPath = dotPath;
		}

		Composite pane = new Composite(parent, SWT.NONE);
		GridLayoutFactory.fillDefaults().applyTo(pane);
		Composite buttonArea = new Composite(pane, SWT.NONE);
		this.browser = new Browser(pane, SWT.NONE);
		if (broker != null) {
			setupElementNavigation(broker);
		}
		addToggleButton(buttonArea, "Horizontal Layout", config::setHorizontalLayout, config.isHorizontalLayout());
		addToggleButton(buttonArea, "Show Labels", config::setShowLabels, config.isShowLabels());
		addToggleButton(buttonArea, "Show R/W dependencies", config::setShowLabelDependencies, config.isShowLabelDependencies());
		addToggleButton(buttonArea, "Show Control Flow", config::setShowCallDependencies, config.isShowCallDependencies());
		addToggleButton(buttonArea, "Show Tasks", config::setShowTasks, config.isShowTasks());

		addPushButton(buttonArea, "Export", () -> {
			FileDialog fd = new FileDialog(parent.getShell(), SWT.SAVE);
			fd.setFilterNames(new String[] { "Scalable Vector Graphics (*.svg)", "Portable Document Format (*.pdf)",
					"Portable Network Graphics (*.png)", "all files (*.*)" });
			fd.setFilterExtensions(new String[] { "*.svg", "*.pdf", "*.png", "*.*" });
			String path = fd.open();
			if (path != null) {
				export(path);
			}
		});

		addPushButton(buttonArea, "+", () -> browser.execute(
				"svg=document.getElementsByTagName(\"svg\")[0]; svg.width.baseVal.value *=1.25; svg.height.baseVal.value *=1.25;"));
		addPushButton(buttonArea, "-", () -> browser.execute(
				"svg=document.getElementsByTagName(\"svg\")[0]; svg.width.baseVal.value /=1.25; svg.height.baseVal.value /=1.25;"));

		RowLayoutFactory.swtDefaults().applyTo(buttonArea);

		GridDataFactory.fillDefaults().align(SWT.FILL, SWT.FILL).grab(true, true).applyTo(browser);
		visualize();
	}

	/**
	 * Setup navigation to a selected element in the model viewer
	 * 
	 * @param broker
	 */
	private void setupElementNavigation(IEventBroker broker) {
		browser.addLocationListener(LocationListener.changingAdapter(c -> {
			c.doit = true;

			Object target = null;
			int idx = c.location.indexOf('#');
			if (idx >= 0) {
				target = graphvizGenerator.getObjectById(c.location.substring(idx + 1));
			}
			if (target != null) {
				HashMap<String, Object> data = new HashMap<>();
				data.put("modelElements", Collections.singletonList(target));
				broker.send("org/eclipse/app4mc/amalthea/editor/SELECT", data);
			}
		}));
	}

	/**
	 * Helper for adding a toggle button
	 * 
	 * @param parent          container element
	 * @param text            label
	 * @param f               button select action; takes the button's selection
	 *                        status as an argument
	 * @param initialSelected initial selection state of the button
	 */
	private void addToggleButton(Composite parent, String text, final Consumer<Boolean> f, boolean initialSelected) {
		final Button btn = new Button(parent, SWT.TOGGLE);
		btn.setText(text);
		btn.setSelection(initialSelected);
		btn.addSelectionListener(new SelectionListener() {

			@Override
			public void widgetDefaultSelected(SelectionEvent evt) {
				widgetSelected(evt);
			}

			@Override
			public void widgetSelected(SelectionEvent evt) {
				f.accept(btn.getSelection());
				visualize();
			}

		});
	}

	/**
	 * Helper for adding a push button
	 * 
	 * @param parent container element
	 * @param text   label
	 * @param cmd    button select action
	 */
	private void addPushButton(Composite parent, String text, Runnable cmd) {
		final Button btn = new Button(parent, SWT.PUSH);
		btn.setText(text);
		btn.addSelectionListener(new SelectionListener() {

			@Override
			public void widgetDefaultSelected(SelectionEvent evt) {
				widgetSelected(evt);
			}

			@Override
			public void widgetSelected(SelectionEvent evt) {
				cmd.run();
			}
		});
	}

	/**
	 * Visualizes a given model element in a browser. The dot graph is constructed
	 * and compiled in a separate thread.
	 */
	private void visualize() {
		new Thread(() -> {
			String dot = graphvizGenerator.createDot(model);

			String result;
			try {
				result = runGraphviz(dot, "-Tsvg");
			} catch (IOException e) {
				result = prepareErrorMessage(e);
				Platform.getLog(RunnableDependencyVisualization.class).error(result, e);
			}
			if (result != null && !browser.isDisposed()) {
				final String browserContent = result;
				browser.getDisplay().asyncExec(() -> {
					if (!browser.isDisposed()) {
						browser.setText(browserContent);
					}
				});
			}

		}).start();

	}

	private String prepareErrorMessage(IOException e) {
		return "Error invoking Graphviz: \"" + e.getMessage()
				+ "\". Make sure you have configured the path to the dot executable properly in the PlantUML preferences.";
	}

	/**
	 * Export the visualization
	 * 
	 * @param path export destination
	 */
	private void export(String path) {
		Display display = Display.getCurrent();
		final Shell shell = display != null ? display.getActiveShell() : null;
		new Thread(() -> {
			String ext = path.substring(path.lastIndexOf('.') + 1);
			final String dot = new GraphvizGenerator(config, !"dot".equals(ext), false).createDot(model);
			try {
				if ("dot".equals(ext)) {
					try (PrintWriter writer = new PrintWriter(path)) {
						writer.append(dot);
					}
				} else {
					runGraphviz(dot, "-T" + ext, "-o", path);
				}
			} catch (IOException e) {
				String msg = prepareErrorMessage(e);
				Platform.getLog(RunnableDependencyVisualization.class).error(msg, e);
				MessageDialog.openError(shell, "Error during export", msg);
			}
		}).start();
	}

	/**
	 * Execute the DOT command, pass the model to stdin and return stdout
	 * 
	 * @param dot  the DOT model to be provided on stdin
	 * @param args arguments to the dot command
	 * @return the command output
	 */
	private String runGraphviz(String dot, String... args) throws IOException {
		List<String> command = new ArrayList<>(args.length + 1);
		command.add(dotPath);
		command.addAll(Arrays.asList(args));
		Process process = new ProcessBuilder(command).redirectError(Redirect.PIPE).start();
		OutputStreamWriter writer = new OutputStreamWriter(process.getOutputStream());
		InputStreamReader reader = new InputStreamReader(process.getInputStream(), StandardCharsets.UTF_8);
		writer.append(dot);
		writer.close();
		StringBuilder sb = new StringBuilder();
		char[] buf = new char[1024];
		int len;
		while ((len = reader.read(buf)) >= 0) {
			sb.append(buf, 0, len);
		}
		return sb.toString();
	}

}