/*******************************************************************************
 * Copyright (c) 2004, 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
 *     Wind River Systems - Ted Williams - [Memory View] Memory View: Workflow Enhancements (Bug 215432)
 *******************************************************************************/
package org.eclipse.debug.internal.ui.views.memory;

import java.util.ArrayList;
import java.util.Enumeration;
import java.util.Hashtable;
import java.util.StringTokenizer;

import org.eclipse.core.commands.AbstractHandler;
import org.eclipse.core.commands.ExecutionEvent;
import org.eclipse.core.commands.ExecutionException;
import org.eclipse.core.runtime.IAdaptable;
import org.eclipse.core.runtime.Platform;
import org.eclipse.core.runtime.preferences.IEclipsePreferences;
import org.eclipse.core.runtime.preferences.InstanceScope;
import org.eclipse.debug.internal.ui.DebugUIMessages;
import org.eclipse.debug.internal.ui.DebugUIPlugin;
import org.eclipse.debug.internal.ui.views.variables.VariablesViewMessages;
import org.eclipse.debug.ui.DebugUITools;
import org.eclipse.debug.ui.IDebugUIConstants;
import org.eclipse.debug.ui.memory.IMemoryRendering;
import org.eclipse.debug.ui.memory.IMemoryRenderingContainer;
import org.eclipse.debug.ui.memory.IMemoryRenderingSite;
import org.eclipse.debug.ui.memory.IMemoryRenderingSite2;
import org.eclipse.debug.ui.memory.IMemoryRenderingSynchronizationService;
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.action.ToolBarManager;
import org.eclipse.jface.viewers.ISelection;
import org.eclipse.jface.viewers.ISelectionChangedListener;
import org.eclipse.jface.viewers.ISelectionProvider;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.jface.viewers.SelectionChangedEvent;
import org.eclipse.jface.viewers.StructuredSelection;
import org.eclipse.swt.SWT;
import org.eclipse.swt.custom.SashForm;
import org.eclipse.swt.custom.ViewForm;
import org.eclipse.swt.events.FocusAdapter;
import org.eclipse.swt.events.FocusEvent;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Event;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.Listener;
import org.eclipse.swt.widgets.ToolBar;
import org.eclipse.ui.IActionBars;
import org.eclipse.ui.IPartListener2;
import org.eclipse.ui.IViewReference;
import org.eclipse.ui.IViewSite;
import org.eclipse.ui.IWorkbenchPart;
import org.eclipse.ui.IWorkbenchPartReference;
import org.eclipse.ui.PartInitException;
import org.eclipse.ui.PlatformUI;
import org.eclipse.ui.commands.ICommandService;
import org.eclipse.ui.contexts.IContextService;
import org.eclipse.ui.handlers.IHandlerService;
import org.eclipse.ui.part.ViewPart;
import org.osgi.service.prefs.BackingStoreException;

/**
 *
 * @since 3.0
 */
public class MemoryView extends ViewPart implements IMemoryRenderingSite2 {

	protected MemoryViewSelectionProvider fSelectionProvider;
	private MemoryViewPartListener fPartListener;

	private SashForm fSashForm;
	private Hashtable<String, IMemoryViewPane> fViewPanes = new Hashtable<>();
	private Hashtable<String, ViewForm> fViewPaneControls = new Hashtable<>();
	private ArrayList<String> fVisibleViewPanes = new ArrayList<>();
	private boolean fVisible;

	private ArrayList<Integer> fWeights = new ArrayList<>();

	private static final String VISIBILITY_PREF = IDebugUIConstants.ID_MEMORY_VIEW + ".viewPanesVisibility"; //$NON-NLS-1$
	private static final String ID_MEMORY_VIEW_CONTEXT = "org.eclipse.debug.ui.memoryview"; //$NON-NLS-1$
	private static final String ID_ADD_MEMORY_BLOCK_COMMAND = "org.eclipse.debug.ui.commands.addMemoryMonitor"; //$NON-NLS-1$
	private static final String ID_TOGGLE_MEMORY_MONITORS_PANE_COMMAND = "org.eclipse.debug.ui.commands.toggleMemoryMonitorsPane"; //$NON-NLS-1$
	private static final String ID_NEXT_MEMORY_BLOCK_COMMAND = "org.eclipse.debug.ui.commands.nextMemoryBlock"; //$NON-NLS-1$
	private static final String ID_NEW_RENDERING_COMMAND = "org.eclipse.debug.ui.commands.newRendering"; //$NON-NLS-1$
	private static final String ID_CLOSE_RENDERING_COMMAND = "org.eclipse.debug.ui.commands.closeRendering"; //$NON-NLS-1$

	public static final String VIEW_PANE_ORIENTATION_PREF = IDebugUIConstants.ID_MEMORY_VIEW + ".orientation"; //$NON-NLS-1$
	public static final int HORIZONTAL_VIEW_ORIENTATION = 0;
	public static final int VERTICAL_VIEW_ORIENTATION = 1;

	private String[] defaultVisiblePaneIds = {
			MemoryBlocksTreeViewPane.PANE_ID,
			IDebugUIConstants.ID_RENDERING_VIEW_PANE_1 };

	private MemoryBlocksTreeViewPane fMemBlkViewer;

	private MemoryViewSynchronizationService fSyncService;

	private boolean fPinMBDisplay = false; // pin memory block display, on by
											// default
	private static int fViewCnt = 0;

	private AbstractHandler fAddHandler;
	private AbstractHandler fToggleMonitorsHandler;
	private AbstractHandler fNextMemoryBlockHandler;
	private AbstractHandler fNewRenderingHandler;
	private AbstractHandler fCloseRenderingHandler;

	private ViewPaneOrientationAction[] fOrientationActions;
	private int fViewOrientation = HORIZONTAL_VIEW_ORIENTATION;

	private String fActivePaneId;

	static class MemoryViewSelectionProvider implements ISelectionProvider, ISelectionChangedListener {
		ArrayList<ISelectionChangedListener> fListeners = new ArrayList<>();

		IStructuredSelection fSelections = new StructuredSelection();

		@Override
		public void addSelectionChangedListener(ISelectionChangedListener listener) {
			if (!fListeners.contains(listener)) {
				fListeners.add(listener);
			}

		}

		@Override
		public ISelection getSelection() {
			return fSelections;
		}

		@Override
		public void removeSelectionChangedListener(ISelectionChangedListener listener) {
			if (fListeners.contains(listener)) {
				fListeners.remove(listener);
			}

		}

		@Override
		public void setSelection(ISelection selection) {
			if (selection instanceof IStructuredSelection) {
				boolean fireChanged = false;

				// only fire change event if the selection has really changed
				if (fSelections.getFirstElement() != ((IStructuredSelection) selection).getFirstElement()) {
					fireChanged = true;
				}

				fSelections = (IStructuredSelection) selection;

				if (fireChanged) {
					fireChanged();
				}
			}
		}

		public void fireChanged() {
			SelectionChangedEvent evt = new SelectionChangedEvent(this, getSelection());
			for (ISelectionChangedListener listener : fListeners) {
				listener.selectionChanged(evt);
			}
		}

		@Override
		public void selectionChanged(SelectionChangedEvent event) {
			ISelection viewPaneSelection = event.getSelection();

			if (viewPaneSelection instanceof IStructuredSelection) {
				Object selected = ((IStructuredSelection) viewPaneSelection).getFirstElement();

				if (selected != null) {
					StructuredSelection strucSelection = new StructuredSelection(new Object[] { selected });
					setSelection(strucSelection);
				} else {
					setSelection(viewPaneSelection);
				}
			}
		}
	}

	class MemoryViewPartListener implements IPartListener2 {
		IMemoryRenderingSite fView = null;

		public MemoryViewPartListener(IMemoryRenderingSite view) {
			fView = view;
		}

		@Override
		public void partActivated(IWorkbenchPartReference ref) {
		}

		@Override
		public void partBroughtToTop(IWorkbenchPartReference ref) {
		}

		@Override
		public void partClosed(IWorkbenchPartReference ref) {
		}

		@Override
		public void partDeactivated(IWorkbenchPartReference ref) {
		}

		@Override
		public void partHidden(IWorkbenchPartReference ref) {

			IWorkbenchPart part = ref.getPart(false);

			if (part == fView) {
				setVisible(false);
			}
		}

		@Override
		public void partVisible(IWorkbenchPartReference ref) {
			IWorkbenchPart part = ref.getPart(false);

			if (part == fView) {
				setVisible(true);
				restoreView();
			}
		}

		@Override
		public void partInputChanged(IWorkbenchPartReference ref) {
		}

		@Override
		public void partOpened(IWorkbenchPartReference ref) {
		}
	}

	@Override
	public void init(IViewSite site) throws PartInitException {
		super.init(site);

		fViewCnt++;
		String secondaryId = site.getSecondaryId();
		if (secondaryId != null) {
			MemoryViewIdRegistry.registerView(secondaryId);
		}

		// only do this the first time
		// not sure if there is a bug in the UI... if the view is
		// not a primary view and if it's hidden, the view is not
		// init and created until it becomes visible.
		if (fViewCnt == 1) {
			// also try to find other views and register
			if (DebugUIPlugin.getActiveWorkbenchWindow() != null && DebugUIPlugin.getActiveWorkbenchWindow().getActivePage() != null) {
				IViewReference references[] = DebugUIPlugin.getActiveWorkbenchWindow().getActivePage().getViewReferences();
				for (IViewReference reference : references) {
					if (reference.getSecondaryId() != null) {
						MemoryViewIdRegistry.registerView(reference.getSecondaryId());
					}
				}
			}
		}

		fSyncService = new MemoryViewSynchronizationService();
	}

	@Override
	public void createPartControl(Composite parent) {
		fSashForm = new SashForm(parent, SWT.HORIZONTAL);

		fSelectionProvider = new MemoryViewSelectionProvider();

		// set up selection provider and listeners
		getSite().setSelectionProvider(fSelectionProvider);

		createMemoryBlocksTreeViewPane(fSashForm);
		createRenderingViewPane(IDebugUIConstants.ID_RENDERING_VIEW_PANE_1);
		createRenderingViewPane(IDebugUIConstants.ID_RENDERING_VIEW_PANE_2);

		setVisible(true);

		// set up weights in sashform
		Integer[] weights = fWeights.toArray(new Integer[fWeights.size()]);
		int[] intWeights = new int[weights.length];
		for (int i = 0; i < weights.length; i++) {
			intWeights[i] = weights[i].intValue();
		}
		fSashForm.setWeights(intWeights);
		loadViewPanesVisibility();

		createOrientationActions();
		loadOrientation();

		fPartListener = new MemoryViewPartListener(this);
		getSite().getPage().addPartListener(fPartListener);
		activateHandlers();
		// restore view pane after finishing creating all the view panes
		restoreView();
	}

	public void activateHandlers() {
		ICommandService commandSupport = getSite().getService(ICommandService.class);
		IHandlerService handlerService = getSite().getService(IHandlerService.class);
		IContextService contextSupport = getSite().getService(IContextService.class);

		if (commandSupport != null && handlerService != null && contextSupport != null) {
			contextSupport.activateContext(ID_MEMORY_VIEW_CONTEXT);

			fAddHandler = new AbstractHandler() {
				@Override
				public Object execute(ExecutionEvent event) throws ExecutionException {
					IAdaptable context = DebugUITools.getPartDebugContext(getSite());
					if (context != null && MemoryViewUtil.isValidSelection(new StructuredSelection(context))) {
						RetargetAddMemoryBlockAction action = new RetargetAddMemoryBlockAction(MemoryView.this);
						action.run();
						action.dispose();
					}
					return null;
				}
			};
			handlerService.activateHandler(ID_ADD_MEMORY_BLOCK_COMMAND, fAddHandler);

			fToggleMonitorsHandler = new AbstractHandler() {
				@Override
				public Object execute(ExecutionEvent event) throws ExecutionException {
					ToggleMemoryMonitorsAction action = new ToggleMemoryMonitorsAction();
					action.init(MemoryView.this);
					action.run();
					action.dispose();
					return null;
				}
			};

			handlerService.activateHandler(ID_TOGGLE_MEMORY_MONITORS_PANE_COMMAND, fToggleMonitorsHandler);

			fNextMemoryBlockHandler = new AbstractHandler() {

				@Override
				public Object execute(ExecutionEvent event) throws ExecutionException {
					SwitchMemoryBlockAction action = new SwitchMemoryBlockAction();
					action.init(MemoryView.this);
					action.run();
					action.dispose();
					return null;
				}
			};
			handlerService.activateHandler(ID_NEXT_MEMORY_BLOCK_COMMAND, fNextMemoryBlockHandler);

			fCloseRenderingHandler = new AbstractHandler() {

				@Override
				public Object execute(ExecutionEvent event) throws ExecutionException {

					IMemoryRenderingContainer container = getContainer(fActivePaneId);
					if (container != null) {
						if (container instanceof RenderingViewPane) {
							if (!((RenderingViewPane) container).canRemoveRendering()) {
								return null;
							}
						}
						IMemoryRendering activeRendering = container.getActiveRendering();
						if (activeRendering != null) {
							container.removeMemoryRendering(activeRendering);
						}
					}

					return null;
				}
			};
			handlerService.activateHandler(ID_CLOSE_RENDERING_COMMAND, fCloseRenderingHandler);

			fNewRenderingHandler = new AbstractHandler() {

				@Override
				public Object execute(ExecutionEvent event) throws ExecutionException {

					IMemoryRenderingContainer container = getContainer(fActivePaneId);

					if (container != null && container instanceof RenderingViewPane) {
						RenderingViewPane pane = (RenderingViewPane) container;
						if (pane.canAddRendering()) {
							pane.showCreateRenderingTab();
						}
					}
					return null;
				}
			};
			handlerService.activateHandler(ID_NEW_RENDERING_COMMAND, fNewRenderingHandler);
		}
	}

	/**
	 *
	 */
	private void createMemoryBlocksTreeViewPane(Composite parent) {

		fMemBlkViewer = new MemoryBlocksTreeViewPane(this);
		fViewPanes.put(MemoryBlocksTreeViewPane.PANE_ID, fMemBlkViewer);
		ViewForm viewerViewForm = new ViewForm(parent, SWT.NONE);
		PlatformUI.getWorkbench().getHelpSystem().setHelp(viewerViewForm, IDebugUIConstants.PLUGIN_ID + ".MemoryView_context"); //$NON-NLS-1$
		fViewPaneControls.put(MemoryBlocksTreeViewPane.PANE_ID, viewerViewForm);
		fWeights.add(Integer.valueOf(15));

		fMemBlkViewer.addSelectionListener(fSelectionProvider);

		Control viewerControl = fMemBlkViewer.createViewPane(viewerViewForm, MemoryBlocksTreeViewPane.PANE_ID, DebugUIMessages.MemoryView_Memory_monitors);
		viewerViewForm.setContent(viewerControl);

		ISelection selection = fMemBlkViewer.getSelectionProvider().getSelection();
		if (selection != null) {
			fSelectionProvider.setSelection(selection);
		}

		ToolBarManager viewerToolBarMgr = new ToolBarManager(SWT.FLAT);
		IAction[] actions = fMemBlkViewer.getActions();
		for (IAction action : actions) {
			viewerToolBarMgr.add(action);
		}
		ToolBar viewerToolbar = viewerToolBarMgr.createControl(viewerViewForm);
		viewerViewForm.setTopRight(viewerToolbar);

		Label viewerLabel = new Label(viewerViewForm, SWT.WRAP);
		viewerLabel.setText(DebugUIMessages.MemoryView_Memory_monitors);
		viewerViewForm.setTopLeft(viewerLabel);

		fMemBlkViewer.getControl().addFocusListener(new FocusAdapter() {
			@Override
			public void focusGained(FocusEvent e) {
				fActivePaneId = fMemBlkViewer.getId();
			}
		});
	}

	/**
	 * @return an activate listener for the given view pane
	 *
	 */
	private Listener createDeactivateListener(final IMemoryViewPane viewPane) {
		Listener deactivateListener = new Listener() {
			private String id = viewPane.getId();

			@Override
			public void handleEvent(Event event) {
				if (fActivePaneId.equals(id)) {
					viewPane.removeSelctionListener(fSelectionProvider);
				}
			}
		};
		return deactivateListener;
	}

	/**
	 * @return a deactivate listener for the given view pane
	 */
	private Listener createActivateListener(final IMemoryViewPane viewPane) {
		Listener activateListener = new Listener() {
			private String id = viewPane.getId();

			@Override
			public void handleEvent(Event event) {
				fActivePaneId = id;
				viewPane.addSelectionListener(fSelectionProvider);
				fSelectionProvider.setSelection(viewPane.getSelectionProvider().getSelection());
			}
		};
		return activateListener;
	}

	/**
	 *
	 */
	public void createRenderingViewPane(final String paneId) {
		final RenderingViewPane renderingPane = new RenderingViewPane(this);
		fViewPanes.put(paneId, renderingPane);
		ViewForm renderingViewForm = new ViewForm(fSashForm, SWT.NONE);
		fViewPaneControls.put(paneId, renderingViewForm);
		fWeights.add(Integer.valueOf(40));

		Control renderingControl = renderingPane.createViewPane(renderingViewForm, paneId, DebugUIMessages.MemoryView_Memory_renderings, true, true);
		PlatformUI.getWorkbench().getHelpSystem().setHelp(renderingControl, IDebugUIConstants.PLUGIN_ID + ".MemoryView_context"); //$NON-NLS-1$
		renderingViewForm.setContent(renderingControl);

		Listener renderingActivateListener = createActivateListener(renderingPane);
		renderingControl.addListener(SWT.Activate, renderingActivateListener);

		Listener renderingDeactivateListener = createDeactivateListener(renderingPane);
		renderingControl.addListener(SWT.Deactivate, renderingDeactivateListener);

	}

	@Override
	public void setFocus() {
		if (fActivePaneId == null) {
			fActivePaneId = fMemBlkViewer.getId();
		}

		IMemoryViewPane pane = getViewPane(fActivePaneId);
		pane.getControl().setFocus();
	}

	@Override
	public void dispose() {
		getSite().getPage().removePartListener(fPartListener);

		Enumeration<IMemoryViewPane> enumeration = fViewPanes.elements();
		while (enumeration.hasMoreElements()) {
			Object element = enumeration.nextElement();
			if (element instanceof IMemoryViewPane) {
				((IMemoryViewPane) element).dispose();
			}
		}

		fViewPaneControls.clear();

		IViewSite viewSite = getViewSite();
		String secondaryId = viewSite.getSecondaryId();
		if (secondaryId != null) {
			MemoryViewIdRegistry.deregisterView(secondaryId);
		}

		fSyncService.shutdown();

		if (fAddHandler != null) {
			fAddHandler.dispose();
		}

		if (fToggleMonitorsHandler != null) {
			fToggleMonitorsHandler.dispose();
		}

		if (fNextMemoryBlockHandler != null) {
			fNextMemoryBlockHandler.dispose();
		}

		super.dispose();
	}

	private void setVisible(boolean visible) {
		IMemoryViewPane[] viewPanes = getViewPanes();

		for (IMemoryViewPane viewPane : viewPanes) {
			// if currently visible, take view pane's visibility into account
			// else force view pane to be visible if it is listed in
			// "visible view panes" array list.
			if (fVisible) {
				viewPane.setVisible(visible && viewPane.isVisible());
			} else {
				if (isViewPaneVisible(viewPane.getId())) {
					viewPane.setVisible(visible);
				}
			}
		}

		fVisible = visible;
	}

	/*
	 * @see
	 * org.eclipse.debug.internal.ui.views.memory.IMultipaneMemoryView#getViewPane
	 * (java.lang.String)
	 */
	public IMemoryViewPane getViewPane(String paneId) {
		return fViewPanes.get(paneId);
	}

	/*
	 * @see
	 * org.eclipse.debug.internal.ui.views.memory.IMultipaneMemoryView#getViewPanes
	 * ()
	 */
	public IMemoryViewPane[] getViewPanes() {
		IMemoryViewPane[] viewPanes = new IMemoryViewPane[fViewPanes.size()];

		Enumeration<IMemoryViewPane> enumeration = fViewPanes.elements();
		int i = 0;
		while (enumeration.hasMoreElements()) {
			viewPanes[i] = enumeration.nextElement();
			i++;
		}

		return viewPanes;
	}

	/**
	 * Restore each view pane from the memory view based on current debug
	 * selection
	 */
	private void restoreView() {
		IMemoryViewPane[] viewPanes = getViewPanes();
		for (IMemoryViewPane viewPane : viewPanes) {
			viewPane.restoreViewPane();
		}
	}

	/*
	 * @see
	 * org.eclipse.debug.internal.ui.views.memory.IMultipaneMemoryView#showViewPane
	 * (boolean, java.lang.String)
	 */
	public void showViewPane(boolean show, String paneId) {

		Control viewPaneControl = fViewPaneControls.get(paneId);

		if (viewPaneControl != null) {
			Control children[] = fSashForm.getChildren();

			for (Control child : children) {
				if (child == viewPaneControl) {
					child.setVisible(show);
					IMemoryViewPane viewPane = fViewPanes.get(paneId);
					if (viewPane != null) {
						viewPane.setVisible(show);
					}
				}
			}
			fSashForm.layout();
		}

		storeViewPaneVisibility();
	}

	/*
	 * @see org.eclipse.debug.internal.ui.views.memory.IMultipaneMemoryView#
	 * isViewPaneVisible(java.lang.String)
	 */
	public boolean isViewPaneVisible(String paneId) {
		return fVisibleViewPanes.contains(paneId);
	}

	private void storeViewPaneVisibility() {
		fVisibleViewPanes.clear();
		StringBuilder visibleViewPanes = new StringBuilder();

		Enumeration<String> enumeration = fViewPaneControls.keys();

		while (enumeration.hasMoreElements()) {
			String paneId = enumeration.nextElement();

			Control control = fViewPaneControls.get(paneId);
			if (control.isVisible()) {
				visibleViewPanes.append(paneId);
				visibleViewPanes.append(","); //$NON-NLS-1$
				fVisibleViewPanes.add(paneId);
			}
		}
		IEclipsePreferences node = InstanceScope.INSTANCE.getNode(DebugUIPlugin.getUniqueIdentifier());
		if (node != null) {
			try {
				node.put(getVisibilityPrefId(), visibleViewPanes.toString());
				node.flush();
			} catch (BackingStoreException e) {
				DebugUIPlugin.log(e);
			}
		}
	}

	private void loadViewPanesVisibility() {
		String visiblePanes = Platform.getPreferencesService().getString(DebugUIPlugin.getUniqueIdentifier(), getVisibilityPrefId(), null, null);

		if (visiblePanes != null && visiblePanes.length() > 0) {
			StringTokenizer tokenizer = new StringTokenizer(visiblePanes, ","); //$NON-NLS-1$
			while (tokenizer.hasMoreTokens()) {
				String paneId = tokenizer.nextToken();
				fVisibleViewPanes.add(paneId);
			}
		} else {
			for (String defaultVisiblePaneId : defaultVisiblePaneIds) {
				fVisibleViewPanes.add(defaultVisiblePaneId);
			}
		}

		Enumeration<String> enumeration = fViewPaneControls.keys();
		while (enumeration.hasMoreElements()) {
			String paneId = enumeration.nextElement();
			boolean visible = false;
			if (fVisibleViewPanes.contains(paneId)) {
				visible = true;
			}

			Control control = fViewPaneControls.get(paneId);
			control.setVisible(visible);

			IMemoryViewPane viewPane = fViewPanes.get(paneId);
			viewPane.setVisible(visible);
		}

		fSashForm.layout();
	}

	private void loadOrientation() {
		fViewOrientation = Platform.getPreferencesService().getInt(DebugUIPlugin.getUniqueIdentifier(), getOrientationPrefId(), HORIZONTAL_VIEW_ORIENTATION, null);

		for (ViewPaneOrientationAction fOrientationAction : fOrientationActions) {
			if (fOrientationAction.getOrientation() == fViewOrientation) {
				fOrientationAction.run();
			}
		}
		updateOrientationActions();
	}

	private void saveOrientation() {
		IEclipsePreferences node = InstanceScope.INSTANCE.getNode(DebugUIPlugin.getUniqueIdentifier());
		if (node != null) {
			try {
				node.putInt(getOrientationPrefId(), fViewOrientation);
				node.flush();
			} catch (BackingStoreException e) {
				DebugUIPlugin.log(e);
			}
		}
	}

	private void updateOrientationActions() {
		for (ViewPaneOrientationAction fOrientationAction : fOrientationActions) {
			if (fOrientationAction.getOrientation() == fViewOrientation) {
				fOrientationAction.setChecked(true);
			} else {
				fOrientationAction.setChecked(false);
			}
		}
	}

	@Override
	public IMemoryRenderingSynchronizationService getSynchronizationService() {
		return fSyncService;
	}

	@Override
	public IMemoryRenderingContainer[] getMemoryRenderingContainers() {
		Enumeration<IMemoryViewPane> enumeration = fViewPanes.elements();
		ArrayList<Object> containers = new ArrayList<>();
		while (enumeration.hasMoreElements()) {
			Object obj = enumeration.nextElement();
			if (obj instanceof IMemoryRenderingContainer) {
				containers.add(obj);
			}
		}

		return containers.toArray(new IMemoryRenderingContainer[containers.size()]);
	}

	@Override
	public IMemoryRenderingContainer getContainer(String id) {
		Object viewPane = fViewPanes.get(id);

		if (viewPane instanceof IMemoryRenderingContainer) {
			return (IMemoryRenderingContainer) viewPane;
		}

		return null;
	}

	public boolean isPinMBDisplay() {
		return fPinMBDisplay;
	}

	public void setPinMBDisplay(boolean pinMBDisplay) {
		fPinMBDisplay = pinMBDisplay;
	}

	private String getVisibilityPrefId() {
		IViewSite vs = getViewSite();
		String viewId = vs.getSecondaryId();

		if (viewId != null)
		 {
			return VISIBILITY_PREF + "." + viewId; //$NON-NLS-1$
		}

		return VISIBILITY_PREF;
	}

	private String getOrientationPrefId() {
		IViewSite vs = getViewSite();
		String viewId = vs.getSecondaryId();

		if (viewId != null)
		 {
			return VIEW_PANE_ORIENTATION_PREF + "." + viewId; //$NON-NLS-1$
		}

		return VIEW_PANE_ORIENTATION_PREF;
	}

	private void createOrientationActions() {
		IActionBars actionBars = getViewSite().getActionBars();
		IMenuManager viewMenu = actionBars.getMenuManager();

		fOrientationActions = new ViewPaneOrientationAction[2];
		fOrientationActions[0] = new ViewPaneOrientationAction(this, HORIZONTAL_VIEW_ORIENTATION);
		fOrientationActions[1] = new ViewPaneOrientationAction(this, VERTICAL_VIEW_ORIENTATION);

		viewMenu.add(new Separator());
		MenuManager layoutSubMenu = new MenuManager(VariablesViewMessages.VariablesView_40);
		layoutSubMenu.add(fOrientationActions[0]);
		layoutSubMenu.add(fOrientationActions[1]);
		viewMenu.add(layoutSubMenu);
		viewMenu.add(new Separator());
	}

	public void setViewPanesOrientation(int orientation) {
		fViewOrientation = orientation;
		if (fViewOrientation == VERTICAL_VIEW_ORIENTATION) {
			fSashForm.setOrientation(SWT.VERTICAL);
		} else {
			fSashForm.setOrientation(SWT.HORIZONTAL);
		}

		saveOrientation();
		updateOrientationActions();
	}

	public int getViewPanesOrientation() {
		return fViewOrientation;
	}

	@Override
	public void setContainerVisible(String id, boolean visible) {
		showViewPane(visible, id);
	}
}