/*******************************************************************************
 * 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
 *******************************************************************************/

package org.eclipse.ui.actions;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import org.eclipse.core.runtime.Assert;
import org.eclipse.jface.action.IContributionItem;
import org.eclipse.jface.action.IMenuManager;
import org.eclipse.jface.action.Separator;
import org.eclipse.jface.util.IPropertyChangeListener;
import org.eclipse.jface.util.PropertyChangeEvent;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.ui.IActionBars;
import org.eclipse.ui.IMemento;
import org.eclipse.ui.IWorkbenchActionConstants;
import org.eclipse.ui.IWorkbenchPage;
import org.eclipse.ui.IWorkbenchPreferenceConstants;
import org.eclipse.ui.IWorkbenchWindow;
import org.eclipse.ui.IWorkingSet;
import org.eclipse.ui.PlatformUI;
import org.eclipse.ui.internal.WorkingSetComparator;
import org.eclipse.ui.internal.WorkingSetMenuContributionItem;
import org.eclipse.ui.internal.actions.ClearWorkingSetAction;
import org.eclipse.ui.internal.actions.EditWorkingSetAction;
import org.eclipse.ui.internal.actions.SelectWorkingSetAction;
import org.eclipse.ui.internal.util.Util;

/**
 * Adds working set filter actions (set / clear / edit)
 *
 * @since 2.1
 */
public class WorkingSetFilterActionGroup extends ActionGroup {
	private static final String TAG_WORKING_SET_NAME = "workingSetName"; //$NON-NLS-1$

	/**
	 * Indicates if working set was changed
	 */
	public static final String CHANGE_WORKING_SET = "changeWorkingSet"; //$NON-NLS-1$

	private static final String START_SEPARATOR_ID = "workingSetGroupStartSeparator"; //$NON-NLS-1$

	private static final String SEPARATOR_ID = "workingSetGroupSeparator"; //$NON-NLS-1$

	private static final String WORKING_SET_ACTION_GROUP = "workingSetActionGroup"; //$NON-NLS-1$

	private IWorkingSet workingSet = null;

	private ClearWorkingSetAction clearWorkingSetAction;

	private SelectWorkingSetAction selectWorkingSetAction;

	private EditWorkingSetAction editWorkingSetAction;

	private IPropertyChangeListener workingSetUpdater;

	private IMenuManager menuManager;

	private IWorkbenchWindow workbenchWindow;

	private IWorkbenchPage page;

	private boolean allowWindowWorkingSetByDefault;

	private CompoundContributionItem mruList;

	/**
	 * Creates a new instance of the receiver.
	 *
	 * @param shell             shell to open dialogs and wizards on
	 * @param workingSetUpdater property change listener notified when a working set
	 *                          is set
	 * @since 3.2 Please note that it is expected that clients treat any selected
	 *        working sets whose {@link IWorkingSet#isAggregateWorkingSet()} method
	 *        returns <code>true</code> somewhat differently from traditional
	 *        working sets. Please see the documentation for
	 *        {@link IWorkbenchPage#getAggregateWorkingSet()} for details.
	 */
	public WorkingSetFilterActionGroup(Shell shell, IPropertyChangeListener workingSetUpdater) {
		Assert.isNotNull(shell);

		this.workingSetUpdater = workingSetUpdater;
		clearWorkingSetAction = new ClearWorkingSetAction(this);
		selectWorkingSetAction = new SelectWorkingSetAction(this, shell);
		editWorkingSetAction = new EditWorkingSetAction(this, shell);
		mruList = new CompoundContributionItem() {

			@Override
			protected IContributionItem[] getContributionItems() {
				IWorkingSet[] workingSets = PlatformUI.getWorkbench().getWorkingSetManager().getRecentWorkingSets();
				List<IContributionItem> items = new ArrayList<>(workingSets.length);
				List<IWorkingSet> sortedWorkingSets = Arrays.asList(workingSets);
				sortedWorkingSets.sort(new WorkingSetComparator());

				int mruMenuCount = 0;
				if (page != null && page.getAggregateWorkingSet() != null) {
					IContributionItem item = new WorkingSetMenuContributionItem(++mruMenuCount,
							WorkingSetFilterActionGroup.this, page.getAggregateWorkingSet());
					items.add(item);
				}
				for (IWorkingSet workingSet : sortedWorkingSets) {
					if (workingSet != null && !workingSet.isAggregateWorkingSet()) {
						IContributionItem item = new WorkingSetMenuContributionItem(++mruMenuCount,
								WorkingSetFilterActionGroup.this, workingSet);
						items.add(item);
					}
				}
				return items.toArray(new IContributionItem[items.size()]);
			}
		};

		workbenchWindow = Util.getWorkbenchWindowForShell(shell);
		allowWindowWorkingSetByDefault = false;
		// set the default working set to be that of the window.
		page = workbenchWindow.getActivePage();
		if (page == null) {
			IWorkbenchPage[] pages = workbenchWindow.getPages();
			if (pages.length > 0) {
				page = pages[0];
			}
		}
	}

	@Override
	public void fillActionBars(IActionBars actionBars) {
		menuManager = actionBars.getMenuManager();

		if (menuManager.find(IWorkbenchActionConstants.MB_ADDITIONS) != null)
			menuManager.insertAfter(IWorkbenchActionConstants.MB_ADDITIONS, new Separator(WORKING_SET_ACTION_GROUP));
		else
			menuManager.add(new Separator(WORKING_SET_ACTION_GROUP));

		menuManager.appendToGroup(WORKING_SET_ACTION_GROUP, selectWorkingSetAction);
		menuManager.appendToGroup(WORKING_SET_ACTION_GROUP, clearWorkingSetAction);
		menuManager.appendToGroup(WORKING_SET_ACTION_GROUP, editWorkingSetAction);
		menuManager.appendToGroup(WORKING_SET_ACTION_GROUP, new Separator(START_SEPARATOR_ID));
		menuManager.appendToGroup(WORKING_SET_ACTION_GROUP, mruList);
		menuManager.appendToGroup(WORKING_SET_ACTION_GROUP, new Separator(SEPARATOR_ID));
	}

	@Override
	public void fillContextMenu(IMenuManager menuManager) {
		menuManager.add(selectWorkingSetAction);
		menuManager.add(clearWorkingSetAction);
		menuManager.add(editWorkingSetAction);
		menuManager.add(new Separator());
		menuManager.add(mruList);
		menuManager.add(new Separator(SEPARATOR_ID));
	}

	/**
	 * Returns the working set which is currently selected.
	 *
	 * @return the working set which is currently selected.
	 */
	public IWorkingSet getWorkingSet() {
		return workingSet;
	}

	/**
	 * Sets the current working set.
	 *
	 * @param newWorkingSet the new working set
	 */
	public void setWorkingSet(IWorkingSet newWorkingSet) {
		IWorkingSet oldWorkingSet = workingSet;

		workingSet = newWorkingSet;
		// Update action
		clearWorkingSetAction.setEnabled(newWorkingSet != null);
		editWorkingSetAction.setEnabled(newWorkingSet != null && newWorkingSet.isEditable());

		firePropertyChange(newWorkingSet, oldWorkingSet);
	}

	/**
	 * Fire the property change to the updater if there is one available.
	 *
	 * @param newWorkingSet the new working set
	 * @param oldWorkingSet the previous working set
	 * @since 3.2
	 */
	private void firePropertyChange(IWorkingSet newWorkingSet, IWorkingSet oldWorkingSet) {
		// Update viewer
		if (workingSetUpdater != null && newWorkingSet != oldWorkingSet) {
			workingSetUpdater.propertyChange(new PropertyChangeEvent(this,
					WorkingSetFilterActionGroup.CHANGE_WORKING_SET, oldWorkingSet, newWorkingSet));
		}
	}

	/**
	 * Saves the state of the filter actions in a memento.
	 *
	 * @param memento the memento
	 * @since 3.3
	 */
	public void saveState(IMemento memento) {
		if (workingSet != null) {
			memento.putString(TAG_WORKING_SET_NAME, workingSet.getName());
		} else {
			memento.putString(TAG_WORKING_SET_NAME, ""); //$NON-NLS-1$
		}
	}

	/**
	 * Restores the state of the filter actions from a memento.
	 * <p>
	 * Note: This method does not refresh the viewer.
	 * </p>
	 *
	 * @param memento the memento with the filter actions content
	 * @since 3.3
	 */
	public void restoreState(IMemento memento) {
		String workingSetName = memento.getString(TAG_WORKING_SET_NAME);
		if (workingSetName != null && workingSetName.length() > 0) {
			setWorkingSet(PlatformUI.getWorkbench().getWorkingSetManager().getWorkingSet(workingSetName));
		} else if (page != null && useWindowWorkingSetByDefault()) {
			setWorkingSet(page.getAggregateWorkingSet());
		}
	}

	private boolean useWindowWorkingSetByDefault() {
		return allowWindowWorkingSetByDefault && PlatformUI.getPreferenceStore()
				.getBoolean(IWorkbenchPreferenceConstants.USE_WINDOW_WORKING_SET_BY_DEFAULT);
	}
}
