/**
 * Copyright (c) 2009, 2010 Anyware Technologies 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:
 *     Anyware Technologies - initial API and implementation
 *     Sebastien Moran <SMoran@sierrawireless.com> - bug 308802, 322393
 *     Jacques Lescot <JLescot@sierrawireless.com> - bug 314677
 *
 * $Id: EmfMasterDetailBlock.java,v 1.25 2010/06/16 17:28:11 bcabe Exp $
 */
package org.eclipse.pde.emfforms.editor;

import org.eclipse.core.databinding.DataBindingContext;
import org.eclipse.core.databinding.property.value.IValueProperty;
import org.eclipse.emf.edit.domain.AdapterFactoryEditingDomain;
import org.eclipse.emf.edit.ui.dnd.*;
import org.eclipse.emf.edit.ui.provider.*;
import org.eclipse.jface.action.*;
import org.eclipse.jface.databinding.swt.SWTObservables;
import org.eclipse.jface.databinding.util.JFaceProperties;
import org.eclipse.jface.layout.GridDataFactory;
import org.eclipse.jface.layout.GridLayoutFactory;
import org.eclipse.jface.viewers.*;
import org.eclipse.pde.emfforms.editor.actions.RemoveAction;
import org.eclipse.pde.emfforms.internal.Activator;
import org.eclipse.swt.SWT;
import org.eclipse.swt.dnd.DND;
import org.eclipse.swt.dnd.Transfer;
import org.eclipse.swt.events.*;
import org.eclipse.swt.layout.FillLayout;
import org.eclipse.swt.widgets.*;
import org.eclipse.ui.IEditorActionBarContributor;
import org.eclipse.ui.PlatformUI;
import org.eclipse.ui.dialogs.FilteredTree;
import org.eclipse.ui.dialogs.PatternFilter;
import org.eclipse.ui.forms.*;
import org.eclipse.ui.forms.widgets.*;

public abstract class EmfMasterDetailBlock extends MasterDetailsBlock implements IDetailsPageProvider, IMenuListener {

	public static final int DEFAULT_SECTION_OPTIONS = Section.DESCRIPTION | ExpandableComposite.TITLE_BAR;

	public static final int DEFAULT_VIEWER_OPTIONS = SWT.BORDER | SWT.H_SCROLL | SWT.V_SCROLL;

	protected EmfFormEditor<?> parentEditor;

	/**
	 * Style constant to indicate that no generic buttons (neither toolbar nor push) should be displayed 
	 */
	public static final int NO_BUTTONS = 0;

	/**
	 * Style constant to indicate whether generic toolbar buttons should be displayed or not 
	 */
	public static final int USE_GENERIC_TOOLBAR_BUTTONS = 1 << 0;

	/**
	 * Style constant to indicate whether generic push buttons should be displayed on the
	 * right-hand side of the tree viewer or not
	 */
	public static final int USE_GENERIC_PUSH_BUTTONS = 1 << 1;

	/**
	 * Style constant to indicate whether custom push buttons should be displayed on the
	 * right-hand side of the tree viewer or not.
	 * If the flag is set, the {@link EmfMasterDetailBlock#createCustomButtons(Composite)} will be called. 
	 */
	public static final int USE_CUSTOM_PUSH_BUTTONS = 1 << 2;

	/**
	 * Style constant to indicate whether generic "Collapse All" and "Expand All" buttons should be displayed
	 * in the toolbar or not. Note that this style is only relevant when the USE_GENERIC_TOOLBAR_BUTTONS style
	 * is applied too, otherwise it has no effect. A separator is also added before adding those buttons.
	 */
	public static final int USE_EXPAND_COLLAPSE_BUTTONS = 1 << 3;

	protected int buttonOption = USE_GENERIC_TOOLBAR_BUTTONS;

	private String title;
	private TreeViewer treeViewer;
	private Button addButton;
	private Button removeButton;

	protected ToolBarManager toolBarManager;
	private IAction removeAction;

	private Section section;

	public EmfMasterDetailBlock(EmfFormEditor<?> editor, String title) {
		this.title = title;
		this.parentEditor = editor;
	}

	public EmfMasterDetailBlock(EmfFormEditor<?> editor, String title, int buttonOption) {
		this(editor, title);
		this.buttonOption = buttonOption;
	}

	@Override
	protected void createMasterPart(final IManagedForm managedForm, Composite parent) {
		FormToolkit toolkit = parentEditor.getToolkit();

		section = toolkit.createSection(parent, getSectionOptions());
		section.setText(title);
		section.setDescription("Edit " + title); //$NON-NLS-1$
		section.marginWidth = 5;
		section.setLayout(new FillLayout());
		section.marginHeight = 5;

		Composite client = toolkit.createComposite(section, SWT.WRAP);
		GridLayoutFactory.fillDefaults().numColumns(showPushButtons() ? 2 : 1).applyTo(client);

		// deliberate use of the 3.4 API
		// TODO try to use the new look using a 3.5 fragment
		FilteredTree ft = new FilteredTree(client, getViewerOptions(), new PatternFilter());
		treeViewer = ft.getViewer();

		// Prevent scrollbars to be managed by the editor's root composite
		GridDataFactory.fillDefaults().grab(true, true).hint(50, 50).applyTo(treeViewer.getTree());

		//Buttons
		if (showPushButtons()) {
			Composite buttonComposite = new Composite(client, SWT.NONE);
			GridLayoutFactory.fillDefaults().numColumns(1).applyTo(buttonComposite);

			if (showGenericPushButtons())
				addButton = createButton(buttonComposite, "Add"); //$NON-NLS-1$
			if (showCustomPushButtons())
				createCustomButtons(buttonComposite);
			if (showGenericPushButtons())
				removeButton = createButton(buttonComposite, "Remove"); //$NON-NLS-1$

			GridDataFactory.fillDefaults().grab(false, false).applyTo(buttonComposite);
		}

		//SectionToolBar
		removeAction = createCustomToolbarRemoveAction();

		if (showToolbarButtons()) {
			toolBarManager = PDEFormToolkit.createSectionToolBarManager(section);
			Action addAction = createCustomToolbarAddAction();
			if (addAction != null) {
				toolBarManager.add(addAction);
			}

			if (removeAction != null) {
				toolBarManager.add(removeAction);
			}

			if (showExpandCollapseButtons()) {
				toolBarManager.add(new Separator());

				toolBarManager.add(new Action("Expand All", Activator.getImageDescriptor("icons/obj16/expand.gif")) { //$NON-NLS-1$ //$NON-NLS-2$
							@Override
							public void run() {
								treeViewer.getTree().setRedraw(false);
								treeViewer.expandAll();
								treeViewer.getTree().setRedraw(true);
							}
						});
				toolBarManager.add(new Action("Collapse All", Activator.getImageDescriptor("icons/obj16/collapse.gif")) { //$NON-NLS-1$ //$NON-NLS-2$
							@Override
							public void run() {
								treeViewer.getTree().setRedraw(false);
								treeViewer.collapseAll();
								treeViewer.getTree().setRedraw(true);
							}
						});
			}
			toolBarManager.update(true);
			section.setTextClient(toolBarManager.getControl());
		}

		treeViewer.setContentProvider(new AdapterFactoryContentProvider(parentEditor.getAdapterFactory()));
		treeViewer.setLabelProvider(new DecoratingLabelProvider(new AdapterFactoryLabelProvider(parentEditor.getAdapterFactory()), PlatformUI.getWorkbench().getDecoratorManager().getLabelDecorator()));
		treeViewer.addFilter(getTreeFilter());

		int dndOperations = DND.DROP_COPY | DND.DROP_MOVE | DND.DROP_LINK;
		Transfer[] transfers = new Transfer[] {LocalTransfer.getInstance()};
		treeViewer.addDragSupport(dndOperations, transfers, new ViewerDragAdapter(treeViewer));
		treeViewer.addDropSupport(dndOperations, transfers, new EditingDomainViewerDropAdapter(parentEditor.getEditingDomain(), treeViewer));

		final SectionPart spart = new SectionPart(section);
		managedForm.addPart(spart);

		treeViewer.addSelectionChangedListener(new ISelectionChangedListener() {
			public void selectionChanged(SelectionChangedEvent event) {
				managedForm.fireSelectionChanged(spart, event.getSelection());
			}
		});

		treeViewer.addOpenListener(new IOpenListener() {
			public void open(OpenEvent event) {
				detailsPart.setFocus();
			}
		});

		// Add listeners to manage activation/deactivation of the treeViewer's
		// ActionBarContributor's global handlers
		configureActionBarManagement();

		if (getRemoveButton() != null) {

			DataBindingContext bindingContext = new DataBindingContext();

			IValueProperty p = JFaceProperties.value(IAction.class, IAction.ENABLED, IAction.ENABLED);
			bindingContext.bindValue(SWTObservables.observeEnabled(getRemoveButton()), p.observe(removeAction));

			//Generic action for remove button
			getRemoveButton().addSelectionListener(new SelectionAdapter() {
				public void widgetSelected(SelectionEvent e) {
					if (removeAction != null)
						removeAction.run();
				}
			});
		}

		createContextMenuFor(treeViewer);

		//update Editor selection
		getEditor().addViewerToListenTo(getTreeViewer());

		section.setClient(client);
	}

	protected int getSectionOptions() {
		return DEFAULT_SECTION_OPTIONS;
	}

	/**
	 * Default styles : SWT.BORDER | SWT.H_SCROLL | SWT.V_SCROLL
	 * 
	 * @return int, style used to create the TreeViewer
	 */
	protected int getViewerOptions() {
		return DEFAULT_VIEWER_OPTIONS;
	}

	/**
	 * Add listeners to manage activation/deactivation of the treeViewer's
	 * ActionBarContributor's global handlers
	 */
	protected void configureActionBarManagement() {
		final IEditorActionBarContributor actionBarContributor = getEditor().getEditorSite().getActionBarContributor();

		if (actionBarContributor != null && actionBarContributor instanceof EmfActionBarContributor) {
			treeViewer.getControl().addFocusListener(new FocusAdapter() {
				@Override
				public void focusGained(FocusEvent e) {
					((EmfActionBarContributor) actionBarContributor).enableGlobalHandlers();
				}

				@Override
				public void focusLost(FocusEvent e) {
					((EmfActionBarContributor) actionBarContributor).disableGlobalHandlers();
				}
			});
		}
	}

	private boolean showPushButtons() {
		return showCustomPushButtons() || showGenericPushButtons();
	}

	private boolean showCustomPushButtons() {
		return ((buttonOption & USE_CUSTOM_PUSH_BUTTONS) > 0);
	}

	private boolean showGenericPushButtons() {
		return ((buttonOption & USE_GENERIC_PUSH_BUTTONS) > 0);
	}

	private boolean showToolbarButtons() {
		return (buttonOption & USE_GENERIC_TOOLBAR_BUTTONS) > 0;
	}

	private boolean showExpandCollapseButtons() {
		return showToolbarButtons() && (buttonOption & USE_EXPAND_COLLAPSE_BUTTONS) > 0;
	}

	protected Action createCustomToolbarAddAction() {
		// Subclass may override this method
		return null;
	}

	/**
	 * Create the Action to be performed when a deletion should be performed.
	 * Default implementation create a {@link RemoveAction} that delegates the job to the DELETE action
	 * registered through the {@link EmfActionBarContributor} of the current {@link EmfFormEditor} 
	 * Subclasses may override this method in order to provide their own Action
	 * @return Action the delete action to perform 
	 */
	protected Action createCustomToolbarRemoveAction() {
		return new RemoveAction(this);
	}

	protected Button createButton(Composite parent, String btnText) {
		Button btn = new Button(parent, SWT.FLAT | SWT.PUSH);
		GridDataFactory.fillDefaults().align(SWT.FILL, SWT.BEGINNING).grab(true, false).applyTo(btn);
		btn.setText(btnText);

		return btn;
	}

	/**
	 * Return a ViewerFilter to apply on the treeViewer
	 * 
	 * @return a ViewerFilter to apply on the treeViewer
	 */
	protected ViewerFilter getTreeFilter() {
		return new ViewerFilter() {
			@Override
			public boolean select(Viewer viewer, Object parentElement, Object element) {
				return true;
			}
		};
	}

	@Override
	protected void createToolBarActions(IManagedForm managedForm) {
		// TODO Auto-generated method stub
	}

	@Override
	protected void registerPages(DetailsPart detailsPart) {
		detailsPart.setPageProvider(this);
	}

	public Object getPageKey(Object object) {
		return AdapterFactoryEditingDomain.unwrap(object).getClass();
	}

	public TreeViewer getTreeViewer() {
		return treeViewer;
	}

	/**
	 * @return The "Add..." button that can be used to hook an element creation wizard, or <code>null</code> if the {@link EmfMasterDetailBlock#useGenericButton} flag is set to <code>false</code> 
	 */
	public Button getGenericAddButton() {
		return addButton;
	}

	protected void createCustomButtons(Composite parent) {
		// Should be overriden by clients wanting to contribute their own "add" button(s) 
	}

	public Button getRemoveButton() {
		return removeButton;
	}

	public void setAddButton(Button addButton) {
		this.addButton = addButton;
	}

	public void setRemoveButton(Button removeButton) {
		this.removeButton = removeButton;
	}

	protected void createContextMenuFor(StructuredViewer viewer) {
		MenuManager contextMenu = new MenuManager("#PopUp"); //$NON-NLS-1$
		contextMenu.add(new Separator("additions")); //$NON-NLS-1$
		contextMenu.setRemoveAllWhenShown(true);
		contextMenu.addMenuListener(this);
		Menu menu = contextMenu.createContextMenu(viewer.getControl());
		viewer.getControl().setMenu(menu);
		IEditorActionBarContributor actionBarContributor = parentEditor.getEditorSite().getActionBarContributor();
		if (actionBarContributor != null && actionBarContributor instanceof EmfActionBarContributor) {
			((EmfActionBarContributor) actionBarContributor).setCreateChildMenuFilter(getCreateChildContextMenuFilter());
			((EmfActionBarContributor) actionBarContributor).setCreateSiblingMenuFilter(getCreateSiblingContextMenuFilter());
		}
		parentEditor.getSite().registerContextMenu(contextMenu, new UnwrappingSelectionProvider(viewer));
	}

	/**
	 * TODO doc
	 */
	protected IFilter getCreateChildContextMenuFilter() {
		return AcceptAllFilter.getInstance();
	}

	/**
	 * TODO doc
	 */
	protected IFilter getCreateSiblingContextMenuFilter() {
		return AcceptAllFilter.getInstance();
	}

	public void menuAboutToShow(IMenuManager manager) {
		if (parentEditor.getEditorSite().getActionBarContributor() != null)
			((IMenuListener) parentEditor.getEditorSite().getActionBarContributor()).menuAboutToShow(manager);
	}

	public EmfFormEditor<?> getEditor() {
		return parentEditor;
	}

	public void setButtonOption(int buttonOption) {
		this.buttonOption = buttonOption;
	}

}