/*******************************************************************************
 * Copyright (c) 2010, 2017 BestSolution.at 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:
 * Tom Schindl <tom.schindl@bestsolution.at> - initial API and implementation
 ******************************************************************************/
package org.eclipse.e4.internal.tools.wizards.model;

import org.eclipse.core.resources.IContainer;
import org.eclipse.core.resources.IResource;
import org.eclipse.core.resources.ResourcesPlugin;
import org.eclipse.core.runtime.IPath;
import org.eclipse.e4.internal.tools.Messages;
import org.eclipse.jdt.core.IJavaProject;
import org.eclipse.jdt.core.JavaModelException;
import org.eclipse.jface.dialogs.IDialogPage;
import org.eclipse.jface.viewers.ISelection;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.jface.window.Window;
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.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.Text;
import org.eclipse.ui.dialogs.ContainerSelectionDialog;

/**
 * The "New" wizard page allows setting the container for the new file as well
 * as the file name. The page will only accept file name without the extension
 * OR with the extension that matches the expected one (e4xmi).
 */

public class NewModelFilePage extends WizardPage {
	public static final String PAGE_NAME = "wizardPage"; //$NON-NLS-1$

	private Text containerText;

	private Text fileText;

	private final ISelection selection;

	private final String defaultFilename;

	/**
	 * Constructor for SampleNewWizardPage.
	 */
	public NewModelFilePage(ISelection selection, String defaultFilename) {
		super(PAGE_NAME);
		setTitle(Messages.NewModelFilePage_NewApplicationModel);
		setDescription(Messages.NewModelFilePage_TheWizardCreates);
		this.selection = selection;
		this.defaultFilename = defaultFilename;
	}

	/**
	 * @see IDialogPage#createControl(Composite)
	 */
	@Override
	public void createControl(Composite parent) {
		final Composite container = new Composite(parent, SWT.NULL);
		final GridLayout layout = new GridLayout();
		container.setLayout(layout);
		layout.numColumns = 3;
		layout.verticalSpacing = 9;
		Label label = new Label(container, SWT.NULL);
		label.setText(Messages.NewModelFilePage_Container);

		containerText = new Text(container, SWT.BORDER | SWT.SINGLE);
		GridData gd = new GridData(GridData.FILL_HORIZONTAL);
		containerText.setLayoutData(gd);
		containerText.addModifyListener(e -> dialogChanged());

		final Button button = new Button(container, SWT.PUSH);
		button.setText(Messages.NewModelFilePage_Browse);
		button.addSelectionListener(new SelectionAdapter() {
			@Override
			public void widgetSelected(SelectionEvent e) {
				handleBrowse();
			}
		});
		label = new Label(container, SWT.NULL);
		label.setText(Messages.NewModelFilePage_FileName);

		fileText = new Text(container, SWT.BORDER | SWT.SINGLE);
		gd = new GridData(GridData.FILL_HORIZONTAL);
		fileText.setLayoutData(gd);
		fileText.addModifyListener(e -> dialogChanged());

		new Label(container, SWT.NONE);

		createAdditionalControls(container);
		initialize();
		dialogChanged();
		setControl(container);
	}

	protected void createAdditionalControls(Composite parent) {

	}

	/**
	 * Tests if the current workbench selection is a suitable container to use.
	 */

	private void initialize() {
		if (selection != null && selection.isEmpty() == false
				&& selection instanceof IStructuredSelection) {
			final IStructuredSelection ssel = (IStructuredSelection) selection;
			if (ssel.size() > 1) {
				return;
			}
			final Object obj = ssel.getFirstElement();

			if (obj instanceof IResource) {
				IContainer container;
				if (obj instanceof IContainer) {
					container = (IContainer) obj;
				} else {
					container = ((IResource) obj).getParent();
				}
				containerText.setText(container.getFullPath().toString());
			} else if (obj instanceof IJavaProject) {
				final IJavaProject container = (IJavaProject) obj;
				try {
					containerText.setText(container.getCorrespondingResource().getFullPath().toString());
				} catch (final JavaModelException e) {
					e.printStackTrace();
				}
			}
		}
		fileText.setText(defaultFilename);
	}

	/**
	 * Uses the standard container selection dialog to choose the new value for
	 * the container field.
	 */

	private void handleBrowse() {
		final ContainerSelectionDialog dialog = new ContainerSelectionDialog(
				getShell(), ResourcesPlugin.getWorkspace().getRoot(), false,
				Messages.NewModelFilePage_SelectTheNewContainer);
		if (dialog.open() == Window.OK) {
			final Object[] result = dialog.getResult();
			if (result.length == 1) {
				containerText.setText(((IPath) result[0]).toString());
			}
		}
	}

	/**
	 * Ensures that both text fields are set.
	 */

	private void dialogChanged() {
		final IResource container = ResourcesPlugin.getWorkspace().getRoot()
				.findMember(IPath.fromOSString(getContainerName()));
		final String fileName = getFileName();

		if (getContainerName().length() == 0) {
			updateStatus(Messages.NewModelFilePage_FileContainerMustBeSpecified);
			return;
		}
		if (container == null
				|| (container.getType() & (IResource.PROJECT | IResource.FOLDER)) == 0) {
			updateStatus(Messages.NewModelFilePage_FileContainerMustExists);
			return;
		}
		if (!container.isAccessible()) {
			updateStatus(Messages.NewModelFilePage_ProjectMustBeWritable);
			return;
		}
		if (fileName.length() == 0) {
			updateStatus(Messages.NewModelFilePage_FileNameMustBeSpecified);
			return;
		}
		if (fileName.replace('\\', '/').indexOf('/', 1) > 0) {
			updateStatus(Messages.NewModelFilePage_FileNameMustBeValid);
			return;
		}
		final int dotLoc = fileName.lastIndexOf('.');
		if (dotLoc != -1) {
			final String ext = fileName.substring(dotLoc + 1);
			if (ext.equalsIgnoreCase("e4xmi") == false) { //$NON-NLS-1$
				updateStatus(Messages.NewModelFilePage_FileExtensionMustBeE4XMI);
				return;
			}
		}
		updateStatus(null);
	}

	private void updateStatus(String message) {
		setErrorMessage(message);
		setPageComplete(message == null);
	}

	public String getContainerName() {
		return containerText.getText();
	}

	public String getFileName() {
		return fileText.getText();
	}
}