/*******************************************************************************
 * Copyright (c) 2000, 2007 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.jdt.internal.ui.navigator;

import org.eclipse.jface.action.Action;
import org.eclipse.jface.action.IAction;
import org.eclipse.jface.action.IMenuManager;
import org.eclipse.jface.action.MenuManager;
import org.eclipse.jface.action.Separator;
import org.eclipse.jface.viewers.StructuredViewer;

import org.eclipse.ui.IActionBars;
import org.eclipse.ui.IWorkbenchActionConstants;
import org.eclipse.ui.PlatformUI;
import org.eclipse.ui.navigator.IExtensionStateModel;

import org.eclipse.jdt.internal.ui.IJavaHelpContextIds;
import org.eclipse.jdt.internal.ui.JavaPluginImages;
import org.eclipse.jdt.internal.ui.actions.MultiActionGroup;
import org.eclipse.jdt.internal.ui.navigator.IExtensionStateConstants.Values;
import org.eclipse.jdt.internal.ui.packageview.PackagesMessages;

/**
 * Adds view menus to switch between flat and hierarchical layout.
 * 
 * @since 3.2
 */
public class CommonLayoutActionGroup extends MultiActionGroup {

	public static final String LAYOUT_GROUP_NAME = "layout"; //$NON-NLS-1$

	private IExtensionStateModel fStateModel;
	private StructuredViewer fStructuredViewer;

	private boolean fHasContributedToViewMenu = false;
	private IAction fHierarchicalLayout = null;
	private IAction fFlatLayoutAction = null;
	private IAction[] fActions;

	private IMenuManager fLayoutSubMenu;

	private class CommonLayoutAction extends Action implements IAction {

		private final boolean fIsFlatLayout;

		public CommonLayoutAction(boolean flat) {
			super("", AS_RADIO_BUTTON); //$NON-NLS-1$
			fIsFlatLayout = flat;
			if (fIsFlatLayout) {
				PlatformUI.getWorkbench().getHelpSystem().setHelp(this, IJavaHelpContextIds.LAYOUT_FLAT_ACTION);
			} else {
				PlatformUI.getWorkbench().getHelpSystem().setHelp(this, IJavaHelpContextIds.LAYOUT_HIERARCHICAL_ACTION);
			}
		}

		/*
		 * @see org.eclipse.jface.action.IAction#run()
		 */
		public void run() {
			if (fStateModel.getBooleanProperty(Values.IS_LAYOUT_FLAT) != fIsFlatLayout) {
				fStateModel.setBooleanProperty(Values.IS_LAYOUT_FLAT, fIsFlatLayout);

				fStructuredViewer.getControl().setRedraw(false);
				try {
					fStructuredViewer.refresh();
				} finally {
					fStructuredViewer.getControl().setRedraw(true);
				}
			}
		}
	}

	public CommonLayoutActionGroup(StructuredViewer structuredViewer,
			IExtensionStateModel stateModel) {
		super();
		fStateModel = stateModel;
		fStructuredViewer = structuredViewer;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see ActionGroup#fillActionBars(IActionBars)
	 */
	public void fillActionBars(IActionBars actionBars) {
		if (!fHasContributedToViewMenu) {

			IMenuManager viewMenu = actionBars.getMenuManager();
			// Create layout sub menu
			if (fLayoutSubMenu == null) {
				fLayoutSubMenu = new MenuManager(PackagesMessages.LayoutActionGroup_label);
				addActions(fLayoutSubMenu);

				viewMenu.insertAfter(IWorkbenchActionConstants.MB_ADDITIONS, new Separator(LAYOUT_GROUP_NAME));
			}

			viewMenu.appendToGroup(LAYOUT_GROUP_NAME, fLayoutSubMenu);

			fHasContributedToViewMenu = true;
		}
	}

	public void unfillActionBars(IActionBars actionBars) {
		if (fHasContributedToViewMenu) {
			// Create layout sub menu
			if (fLayoutSubMenu != null) {
				actionBars.getMenuManager().remove(fLayoutSubMenu);
				fLayoutSubMenu.dispose();
				fLayoutSubMenu= null;
			}

			fHasContributedToViewMenu = false;
		}
	}

	private IAction[] createActions() {

		fFlatLayoutAction = new CommonLayoutAction(true);
		fFlatLayoutAction.setText(PackagesMessages.LayoutActionGroup_flatLayoutAction_label);
		JavaPluginImages.setLocalImageDescriptors(fFlatLayoutAction, "flatLayout.gif"); //$NON-NLS-1$

		fHierarchicalLayout = new CommonLayoutAction(false);
		fHierarchicalLayout.setText(PackagesMessages.LayoutActionGroup_hierarchicalLayoutAction_label);
		JavaPluginImages.setLocalImageDescriptors(fHierarchicalLayout, "hierarchicalLayout.gif"); //$NON-NLS-1$

		return new IAction[] { fFlatLayoutAction, fHierarchicalLayout };
	}

	public void setFlatLayout(boolean flatLayout) {
		if (fActions == null) {
			fActions = createActions();
			
			// indicates check the flat action
			setActions(fActions, flatLayout ? 0	: 1);
		}
		fHierarchicalLayout.setChecked(!flatLayout);
		fFlatLayoutAction.setChecked(flatLayout); 
	}

}
