/*******************************************************************************
 * Copyright (c) 2005, 2018 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
 *     Jeanderson Candido <http://jeandersonbc.github.io> - Bug 414565
 *     Lars Vogel <Lars.Vogel@vogella.com> - Bug 475361
 *******************************************************************************/
package org.eclipse.jface.snippets.wizard;

import java.util.ArrayList;
import java.util.List;

import org.eclipse.jface.viewers.ArrayContentProvider;
import org.eclipse.jface.viewers.TableViewer;
import org.eclipse.jface.wizard.IWizardPage;
import org.eclipse.jface.wizard.Wizard;
import org.eclipse.jface.wizard.WizardDialog;
import org.eclipse.jface.wizard.WizardPage;
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.SelectionAdapter;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.layout.FillLayout;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.ProgressBar;
import org.eclipse.swt.widgets.Shell;

/**
 * Example how to load data from a background thread into a TableViewer
 *
 * @author Tom Schindl &lt;tom.schindl@bestsolution.at&gt;
 * @since 1.0
 */
public class Snippet047WizardWithLongRunningOperation {

	private static class MyWizard extends Wizard {

		private final int loadingType;

		public MyWizard(int loadingType) {
			this.loadingType = loadingType;
		}

		@Override
		public void addPages() {
			addPage(new MyWizardPage("Standard Page"));
			addPage(new MyWizardPageThread("Thread Page", loadingType));
		}

		@Override
		public boolean performFinish() {
			return true;
		}

		@Override
		public boolean canFinish() {
			IWizardPage[] pages = getPages();
			for (IWizardPage page : pages) {
				if (!page.isPageComplete()) {
					return false;
				}
			}
			return true;
		}

	}

	private static class MyWizardPage extends WizardPage {

		protected MyWizardPage(String pageName) {
			super(pageName);
			setTitle(pageName);
		}

		@Override
		public void createControl(Composite parent) {
			Composite comp = new Composite(parent, SWT.NONE);
			setControl(comp);
		}
	}

	private static class MyWizardPageThread extends WizardPage {
		private final int loadingType;
		private boolean loading = true;
		private TableViewer v;

		protected MyWizardPageThread(String pageName, int loadingType) {
			super(pageName);
			this.loadingType = loadingType;
			setTitle(pageName);
		}

		@Override
		public void createControl(final Composite parent) {
			final Composite comp = new Composite(parent, SWT.NONE);
			comp.setLayout(new GridLayout(1, false));

			v = new TableViewer(comp, SWT.FULL_SELECTION);
			v.setContentProvider(ArrayContentProvider.getInstance());
			v.getTable().setLayoutData(new GridData(GridData.FILL_BOTH));
			v.addSelectionChangedListener(event -> getWizard().getContainer().updateButtons());

			final Composite barContainer = new Composite(comp, SWT.NONE);
			barContainer.setLayoutData(new GridData(GridData.FILL_HORIZONTAL));
			barContainer.setLayout(new GridLayout(2, false));

			Label l = new Label(barContainer, SWT.NONE);
			l.setText("Loading Data");

			final ProgressBar bar = new ProgressBar(barContainer,
					(loadingType == 1) ? SWT.INDETERMINATE : SWT.NONE);
			bar.setLayoutData(new GridData(GridData.FILL_HORIZONTAL));

			if (loadingType == 2) {
				bar.setMaximum(10);
			}

			setControl(comp);

			Thread t = new Thread() {

				@Override
				public void run() {
					final List<MyModel> ms = new ArrayList<>();
					if (loadingType == 1) {
						try {
							Thread.sleep(10000);
							for (int i = 0; i < 10; i++) {
								ms.add(new MyModel(i));
							}
							if (v.getTable().isDisposed()) {
								return;
							}
							parent.getDisplay().asyncExec(() -> {
								v.setInput(ms);
								((GridData) barContainer.getLayoutData()).exclude = true;
								comp.layout(true);
							});
						} catch (InterruptedException e) {
							e.printStackTrace();
						}

					} else {
						parent.getDisplay().syncExec(() -> v.setInput(ms));

						for (int i = 0; i < 10; i++) {
							final int j = i;
							if (v.getTable().isDisposed()) {
								return;
							}
							parent.getDisplay().asyncExec(() -> {
								MyModel tmp = new MyModel(j);
								v.add(tmp);
								ms.add(tmp);
								bar.setSelection(j + 1);
							});

							try {
								Thread.sleep(1000);
							} catch (InterruptedException e) {
								e.printStackTrace();
							}
						}

						parent.getDisplay().asyncExec(() -> {
							((GridData) barContainer.getLayoutData()).exclude = true;
							comp.layout(true);
						});
					}

					parent.getDisplay().syncExec(() -> {
						loading = false;
						getWizard().getContainer().updateButtons();
					});
				}

			};
			t.start();
		}

		@Override
		public boolean isPageComplete() {
			return !loading && !v.getSelection().isEmpty();
		}

	}

	private static class MyModel {
		private final int index;

		public MyModel(int index) {
			this.index = index;
		}

		@Override
		public String toString() {
			return "Item-" + index;
		}
	}

	public static void main(String[] args) {
		Display display = new Display();

		final Shell shell = new Shell(display);
		shell.setLayout(new FillLayout());

		Button b = new Button(shell, SWT.PUSH);
		b.setText("Load in one Chunk");
		b.addSelectionListener(new SelectionAdapter() {

			@Override
			public void widgetSelected(SelectionEvent e) {
				WizardDialog dialog = new WizardDialog(shell, new MyWizard(1));
				dialog.open();
			}

		});

		b = new Button(shell, SWT.PUSH);
		b.setText("Load Item by Item");
		b.addSelectionListener(new SelectionAdapter() {

			@Override
			public void widgetSelected(SelectionEvent e) {
				WizardDialog dialog = new WizardDialog(shell, new MyWizard(2));
				dialog.open();
			}

		});

		shell.open();

		while (!shell.isDisposed()) {
			if (!display.readAndDispatch())
				display.sleep();
		}
		display.dispose();
	}
}