/*******************************************************************************
 * Copyright (c) 2000, 2015 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
 *   Sebastian Davids <sdavids@gmx.de> - Fix for bug 19346 - Dialog
 *     font should be activated and used by other components.
 *******************************************************************************/

package org.eclipse.ui.dialogs;

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

import org.eclipse.core.resources.IContainer;
import org.eclipse.core.runtime.IPath;
import org.eclipse.swt.SWT;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.Listener;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.ui.PlatformUI;
import org.eclipse.ui.internal.ide.IDEWorkbenchMessages;
import org.eclipse.ui.internal.ide.IIDEHelpContextIds;
import org.eclipse.ui.internal.ide.misc.ContainerSelectionGroup;

/**
 * A standard selection dialog which solicits a container resource from the
 * user. The <code>getResult</code> method returns the selected container
 * resource.
 * <p>
 * This class may be instantiated; it is not intended to be subclassed.
 * </p>
 * <p>
 * Example:
 * </p>
 *
 * <pre>
 * ContainerSelectionDialog dialog = new ContainerSelectionDialog(getShell(), initialSelection, allowNewContainerName(),
 * 		msg);
 * dialog.open();
 * Object[] result = dialog.getResult();
 * </pre>
 *
 * @noextend This class is not intended to be subclassed by clients.
 */
public class ContainerSelectionDialog extends SelectionDialog {
	/**
	 *
	 */
	private static final String EMPTY_STRING = ""; //$NON-NLS-1$

	// the widget group;
	ContainerSelectionGroup group;

	// the root resource to populate the viewer with
	private IContainer initialSelection;

	// allow the user to type in a new container name
	private boolean allowNewContainerName = true;

	// the validation message
	Label statusMessage;

	// for validating the selection
	ISelectionValidator validator;

	// show closed projects by default
	private boolean showClosedProjects = true;

	/**
	 * Creates a resource container selection dialog rooted at the given resource.
	 * All selections are considered valid.
	 *
	 * @param parentShell           the parent shell
	 * @param initialRoot           the initial selection in the tree
	 * @param allowNewContainerName <code>true</code> to enable the user to type in
	 *                              a new container name, and <code>false</code> to
	 *                              restrict the user to just selecting from
	 *                              existing ones
	 * @param message               the message to be displayed at the top of this
	 *                              dialog, or <code>null</code> to display a
	 *                              default message
	 */
	public ContainerSelectionDialog(Shell parentShell, IContainer initialRoot, boolean allowNewContainerName,
			String message) {
		super(parentShell);
		setTitle(IDEWorkbenchMessages.ContainerSelectionDialog_title);
		this.initialSelection = initialRoot;
		this.allowNewContainerName = allowNewContainerName;
		if (message != null) {
			setMessage(message);
		} else {
			setMessage(IDEWorkbenchMessages.ContainerSelectionDialog_message);
		}
		setShellStyle(getShellStyle() | SWT.SHEET);
	}

	@Override
	protected void configureShell(Shell shell) {
		super.configureShell(shell);
		PlatformUI.getWorkbench().getHelpSystem().setHelp(shell, IIDEHelpContextIds.CONTAINER_SELECTION_DIALOG);
	}

	@Override
	protected Control createDialogArea(Composite parent) {
		// create composite
		Composite area = (Composite) super.createDialogArea(parent);

		Listener listener = event -> {
			if (statusMessage != null && validator != null) {
				String errorMsg = validator.isValid(group.getContainerFullPath());
				if (errorMsg == null || errorMsg.equals(EMPTY_STRING)) {
					statusMessage.setText(EMPTY_STRING);
					getOkButton().setEnabled(true);
				} else {
					statusMessage.setText(errorMsg);
					getOkButton().setEnabled(false);
				}
			}
		};

		// container selection group
		group = new ContainerSelectionGroup(area, listener, allowNewContainerName, getMessage(), showClosedProjects);
		if (initialSelection != null) {
			group.setSelectedContainer(initialSelection);
		}

		statusMessage = new Label(area, SWT.WRAP);
		statusMessage.setLayoutData(new GridData(GridData.FILL_HORIZONTAL));
		statusMessage.setText(" \n "); //$NON-NLS-1$
		statusMessage.setFont(parent.getFont());

		return dialogArea;
	}

	/**
	 * The <code>ContainerSelectionDialog</code> implementation of this
	 * <code>Dialog</code> method builds a list of the selected resource containers
	 * for later retrieval by the client and closes this dialog.
	 */
	@Override
	protected void okPressed() {

		List<IPath> chosenContainerPathList = new ArrayList<>();
		IPath returnValue = group.getContainerFullPath();
		if (returnValue != null) {
			chosenContainerPathList.add(returnValue);
		}
		setResult(chosenContainerPathList);
		super.okPressed();
	}

	/**
	 * Sets the validator to use.
	 *
	 * @param validator A selection validator
	 */
	public void setValidator(ISelectionValidator validator) {
		this.validator = validator;
	}

	/**
	 * Set whether or not closed projects should be shown in the selection dialog.
	 *
	 * @param show Whether or not to show closed projects.
	 */
	public void showClosedProjects(boolean show) {
		this.showClosedProjects = show;
	}
}
