/*******************************************************************************
 * Copyright (c) 2003, 2006 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.jst.j2ee.internal.wizard;

import java.lang.reflect.InvocationTargetException;

import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IConfigurationElement;
import org.eclipse.core.runtime.IExecutableExtension;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.jst.j2ee.internal.plugin.CommonEditorUtility;
import org.eclipse.swt.widgets.Display;
import org.eclipse.ui.IImportWizard;
import org.eclipse.ui.IWorkbench;
import org.eclipse.ui.wizards.newresource.BasicNewProjectResourceWizard;
import org.eclipse.wst.common.frameworks.datamodel.IDataModel;
import org.eclipse.wst.common.frameworks.internal.datamodel.ui.DataModelWizard;
import org.eclipse.wst.web.internal.DelegateConfigurationElement;

/**
 * <p>
 * Serves as a base class for Wizards which import J2EE artifact structures into Eclipse projects.
 * </p>
 * <p>
 * Subclasses must provide the methods that are required by
 * {@see org.eclipse.wst.common.frameworks.internal.ui.WTPWizard}.
 * </p>
 * <p>
 * Optionally, subclasses may also override the following methods:
 * <ul>
 * <li>{@link #getFinalPerspectiveID()}
 * <li>{@link #doInit()()}
 * <li>{@link #doDispose()()}
 * </ul>
 * </p>
 * <p>
 * The base class will ensure that the Wizard is not spawned unless all open editors are in a
 * non-dirty state. Additionally, the selection from the active view which spanwed the wizard will
 * be made available to subclasses via {@link #getCurrentSelection()}.
 * </p>
 */
public abstract class J2EEArtifactImportWizard extends DataModelWizard implements IImportWizard, IExecutableExtension {

	/**
	 * <p>
	 * Constant used to identify the key of the main page of the Wizard.
	 * </p>
	 */
	protected static final String MAIN_PG = "main"; //$NON-NLS-1$

	private IConfigurationElement configurationElement;
	private IStructuredSelection selection;

	/**
	 * <p>
	 * The default constructor. Creates a wizard with no selection, no model instance, and no
	 * operation instance. The model and operation will be created as needed.
	 * </p>
	 */
	public J2EEArtifactImportWizard() {
		super();
	}

	/**
	 * <p>
	 * The model is used to prepopulate the wizard controls and interface with the operation.
	 * </p>
	 * 
	 * @param model
	 *            The model parameter is used to pre-populate wizard controls and interface with the
	 *            operation
	 */
	public J2EEArtifactImportWizard(IDataModel model) {
		super(model);
	}

	/**
	 * <p>
	 * The selection is used to pre-populate values in the Wizard dialog controls.
	 * </p>
	 * 
	 * @see org.eclipse.ui.IWorkbenchWizard#init(org.eclipse.ui.IWorkbench,
	 *      org.eclipse.jface.viewers.IStructuredSelection)
	 * 
	 * @param workbench
	 *            the current workbench parent of the wizard
	 * @param aSelection
	 *            the selection from the view used to start the wizard (if any)
	 */
	public final void init(IWorkbench workbench, IStructuredSelection aSelection) {
		this.selection = aSelection;
		setNeedsProgressMonitor(true);
		doInit();
	}

	/**
	 * <p>
	 * Calls {@link #doDispose()}and then nulls out fields that are no longer needed once the
	 * wizard completes.
	 * </p>
	 * 
	 * @see com.ibm.etools.j2ee.common.wizard.datamodel.WTPWizard#dispose()
	 */
	public final void dispose() {
		super.dispose();
		doDispose();
		this.selection = null;
		this.configurationElement = null;
	}

	/**
	 * <p>
	 * Invoked after the selection has been saved off in
	 * {@link #init(IWorkbench, IStructuredSelection)}. Should be used to handle any specific
	 * Wizard initialization.
	 * </p>
	 */
	protected void doInit() {
		// init
	}

	/**
	 * <p>
	 * Invoked from {@link #dispose()}. Should be used to handle any specific Wizard disposal.
	 * </p>
	 */
	protected void doDispose() {
		// dispose
	}

	/**
	 * <p>
	 * The return value of this method will be used to suggest a final perspective to the user once
	 * the wizard completes.
	 * </p>
	 * 
	 * @return Returns the J2EE Perpsective ID by default
	 */
	protected String getFinalPerspectiveID() {
		return null;
	}

	/**
	 * <p>
	 * Prompts the user to save open, dirty editors.
	 * </p>
	 * 
	 * @return true only if all editors are saved
	 */
	protected final boolean prePerformFinish() {
		if (!CommonEditorUtility.promptToSaveAllDirtyEditors()) {
			return false;
		}
		//Must have selected to not save, but should close all remaining
		CommonEditorUtility.closeAllEditors();
		return super.prePerformFinish();
	}

	/**
	 * <p>
	 * Invoked after the user has clicked the "Finish" button of the wizard. The default
	 * implementation will attempt to update the final perspective to the value specified by
	 * {@link #getFinalPerspectiveID() }
	 * </p>
	 * 
	 * @throws InvocationTargetException
	 * 
	 * @see org.eclipse.wst.common.frameworks.internal.ui.wizard.WTPWizard#postPerformFinish()
	 */
	protected final void postPerformFinish() throws InvocationTargetException {
		super.postPerformFinish();
		if (getFinalPerspectiveID() != null && getFinalPerspectiveID().length() > 0) {
			final IConfigurationElement element = new DelegateConfigurationElement(configurationElement) {
				public String getAttribute(String aName) {
					if (aName.equals("finalPerspective")) { //$NON-NLS-1$
						return getFinalPerspectiveID();
					}
					return super.getAttribute(aName);
				}
			};
			Display.getDefault().asyncExec(new Runnable() {
				public void run() {
					BasicNewProjectResourceWizard.updatePerspective(element);
				}
			});
		} else {
			Display.getDefault().asyncExec(new Runnable() {
				public void run() {
					BasicNewProjectResourceWizard.updatePerspective(configurationElement);
				}
			});
		}
	}

	/**
	 * {@inheritDoc}
	 * 
	 * <p>
	 * The configuration element is saved to use when the wizard completes in order to change the
	 * current perspective using either (1) the value specified by {@see #getFinalPerspectiveID()}
	 * or (2) the value specified by the finalPerspective attribute in the Wizard's configuration
	 * element.
	 * </p>
	 * 
	 * @see org.eclipse.core.runtime.IExecutableExtension#setInitializationData(org.eclipse.core.runtime.IConfigurationElement,
	 *      java.lang.String, java.lang.Object)
	 */
	public final void setInitializationData(IConfigurationElement config, String propertyName, Object data) throws CoreException {
		this.configurationElement = config;
	}

	/**
	 * @return Returns the selection.
	 */
	protected final IStructuredSelection getSelection() {
		return selection;
	}

}