/*******************************************************************************
 * Copyright (c) 2005, 2008 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.ui;

import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IConfigurationElement;
import org.eclipse.core.runtime.IExecutableExtension;
import org.eclipse.core.runtime.IExecutableExtensionFactory;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.Status;
import org.eclipse.ui.internal.ShowInMenu;
import org.eclipse.ui.internal.dialogs.ContentTypesPreferencePage;
import org.eclipse.ui.internal.dialogs.DecoratorsPreferencePage;
import org.eclipse.ui.internal.dialogs.EditorsPreferencePage;
import org.eclipse.ui.internal.dialogs.FileEditorsPreferencePage;
import org.eclipse.ui.internal.dialogs.PerspectivesPreferencePage;
import org.eclipse.ui.internal.dialogs.ViewsPreferencePage;
import org.eclipse.ui.internal.dialogs.WorkbenchPreferencePage;
import org.eclipse.ui.internal.keys.KeysPreferencePage;
import org.eclipse.ui.internal.keys.NewKeysPreferencePage;
import org.eclipse.ui.internal.progress.ProgressView;
import org.eclipse.ui.internal.themes.ColorsAndFontsPreferencePage;
import org.eclipse.ui.internal.wizards.preferences.PreferencesExportWizard;
import org.eclipse.ui.internal.wizards.preferences.PreferencesImportWizard;

/**
 * Factory for the workbench's public extensions.
 * <p>
 * This allows the extensions to be made available for use by RCP applications
 * without exposing their concrete implementation classes.
 * </p>
 * 
 * @since 3.1
 */
public class ExtensionFactory implements IExecutableExtensionFactory,
		IExecutableExtension {

	/**
	 * Factory ID for the Appearance preference page.
	 */
	public static final String APPEARANCE_PREFERENCE_PAGE = "appearancePreferencePage"; //$NON-NLS-1$

	/**
	 * Factory ID for the Colors and Fonts preference page.
	 */
	public static final String COLORS_AND_FONTS_PREFERENCE_PAGE = "colorsAndFontsPreferencePage"; //$NON-NLS-1$

	/**
	 * Factory ID for the Decorators preference page.
	 */
	public static final String DECORATORS_PREFERENCE_PAGE = "decoratorsPreferencePage"; //$NON-NLS-1$

	/**
	 * Factory ID for the Editors preference page.
	 */
	public static final String EDITORS_PREFERENCE_PAGE = "editorsPreferencePage"; //$NON-NLS-1$

	/**
	 * Factory ID for the File Associations preference page.
	 */
	public static final String FILE_ASSOCIATIONS_PREFERENCE_PAGE = "fileAssociationsPreferencePage"; //$NON-NLS-1$

	/**
	 * Factory ID for the Keys preference page.
	 */
	public static final String KEYS_PREFERENCE_PAGE = "keysPreferencePage"; //$NON-NLS-1$

	/**
	 * Factory ID for the new (and improved) keys preference page.
	 * 
	 * @since 3.2
	 */
	public static final String NEW_KEYS_PREFERENCE_PAGE = "newKeysPreferencePage"; //$NON-NLS-1$

	/**
	 * Factory ID for the Perspectives preference page.
	 */
	public static final String PERSPECTIVES_PREFERENCE_PAGE = "perspectivesPreferencePage"; //$NON-NLS-1$

	/**
	 * Factory ID for the Preferences export wizard.
	 */
	public static final String PREFERENCES_EXPORT_WIZARD = "preferencesExportWizard"; // $//$NON-NLS-1$

	/**
	 * Factory ID for the Preferences import wizard.
	 */
	public static final String PREFERENCES_IMPORT_WIZARD = "preferencesImportWizard"; // $//$NON-NLS-1$

	/**
	 * Factory ID for the Progress view.
	 */
	public static final String PROGRESS_VIEW = "progressView"; //$NON-NLS-1$

	/**
	 * Factory ID for the Workbench preference page.
	 */
	public static final String WORKBENCH_PREFERENCE_PAGE = "workbenchPreferencePage"; //$NON-NLS-1$

	/**
	 * Factory ID for the ContentTypes preference page.
	 */
	public static final String CONTENT_TYPES_PREFERENCE_PAGE = "contentTypesPreferencePage"; //$NON-NLS-1$

	/**
	 * Factory ID for the show in contribution.
	 * 
	 * @since 3.4
	 */
	public static final String SHOW_IN_CONTRIBUTION = "showInContribution"; //$NON-NLS-1$

	private IConfigurationElement config;

	private String id;

	private String propertyName;

	/**
	 * Constructs a new workbench extension factory.
	 */
	public ExtensionFactory() {
		// do nothing
	}

	private Object configure(Object obj) throws CoreException {
		if (obj instanceof IExecutableExtension) {
			((IExecutableExtension) obj).setInitializationData(config,
					propertyName, null);
		}
		return obj;
	}

	/**
	 * Creates the object referenced by the factory id obtained from the
	 * extension data.
	 */
	public Object create() throws CoreException {
		if (APPEARANCE_PREFERENCE_PAGE.equals(id)) {
			return configure(new ViewsPreferencePage());
		}
		if (COLORS_AND_FONTS_PREFERENCE_PAGE.equals(id)) {
			return configure(new ColorsAndFontsPreferencePage());
		}
		if (DECORATORS_PREFERENCE_PAGE.equals(id)) {
			return configure(new DecoratorsPreferencePage());
		}
		if (EDITORS_PREFERENCE_PAGE.equals(id)) {
			return configure(new EditorsPreferencePage());
		}
		if (FILE_ASSOCIATIONS_PREFERENCE_PAGE.equals(id)) {
			return configure(new FileEditorsPreferencePage());
		}
		if (KEYS_PREFERENCE_PAGE.equals(id)) {
			return configure(new KeysPreferencePage());
		}
		if (NEW_KEYS_PREFERENCE_PAGE.equals(id)) {
			return configure(new NewKeysPreferencePage());
		}
		if (PERSPECTIVES_PREFERENCE_PAGE.equals(id)) {
			return configure(new PerspectivesPreferencePage());
		}
		if (PREFERENCES_EXPORT_WIZARD.equals(id)) {
			return configure(new PreferencesExportWizard());
		}
		if (PREFERENCES_IMPORT_WIZARD.equals(id)) {
			return configure(new PreferencesImportWizard());
		}
		if (PROGRESS_VIEW.equals(id)) {
			return configure(new ProgressView());
		}
		if (WORKBENCH_PREFERENCE_PAGE.equals(id)) {
			return configure(new WorkbenchPreferencePage());
		}
		if (CONTENT_TYPES_PREFERENCE_PAGE.equals(id)) {
			return configure(new ContentTypesPreferencePage());
		}
		if (SHOW_IN_CONTRIBUTION.equals(id)) {
			ShowInMenu showInMenu = new ShowInMenu();
			return showInMenu;
		}

		throw new CoreException(new Status(IStatus.ERROR, PlatformUI.PLUGIN_ID,
				0, "Unknown id in data argument for " + getClass(), null)); //$NON-NLS-1$
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.core.runtime.IExecutableExtension#setInitializationData(org.eclipse.core.runtime.IConfigurationElement,
	 *      java.lang.String, java.lang.Object)
	 */
	public void setInitializationData(IConfigurationElement config,
			String propertyName, Object data) throws CoreException {
		if (data instanceof String) {
			id = (String) data;
		} else {
			throw new CoreException(new Status(IStatus.ERROR,
					PlatformUI.PLUGIN_ID, 0,
					"Data argument must be a String for " + getClass(), null)); //$NON-NLS-1$
		}
		this.config = config;
		this.propertyName = propertyName;
	}
}