/*******************************************************************************
 * Copyright 2015 xWic group (http://www.xwic.de)
 *
 * Licensed under the Apache License, Version 2.0 (the "License").
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * 		http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software 
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and 
 * limitations under the License.
 *  
 *******************************************************************************/
package de.jwic.controls.wizard;

import java.util.ArrayList;
import java.util.List;

import de.jwic.base.SessionContext;

/**
 * Provides and controlles a set of WizardPages. A Wizard is hosted within a
 * WizardDialog.
 * 
 * @author Florian Lippisch
 * @version $Revision: 1.2 $
 */
public abstract class AbstractWizard<WP extends WizardPage> {

	private List<WP> pages = new ArrayList<WP>();
	private String title = "Wizard";
	private int width = 0;
	private int height = 0;

	/**
	 * Returns the title
	 * 
	 * @return
	 */
	public String getTitle() {
		return title;
	}

	/**
	 * Set the title of the wizard.
	 * 
	 * @param newTitle
	 */
	public void setTitle(String newTitle) {
		title = newTitle;
	}

	/**
	 * Creates the WizardPages used by this wizard and returns the initial page.
	 * 
	 * @param site
	 * @return
	 */
	public abstract WP createWizardPages(SessionContext sessionContext);

	/**
	 * Add a WizardPage to the wizard.
	 * 
	 * @param page
	 */
	protected final void addWizardPage(WP page) {

		pages.add(page);

	}

	/**
	 * Returns true if the specified page has a following page. This method may
	 * be overriden to implement content-specific page navigation.
	 * 
	 * @param page
	 * @return
	 */
	public boolean hasNext(WP page) {
		int idx = pages.indexOf(page);
		return (idx != -1 && (idx < pages.size() - 1));
	}

	/**
	 * Returns the following page to the specified page. This method may be
	 * overriden to implement content-specific page navigation.
	 * 
	 * @param page
	 * @return
	 */
	public WP getNextPage(WP page) {
		int idx = pages.indexOf(page);
		if (idx != -1 && (idx < pages.size() - 1)) {
			return pages.get(idx + 1);
		}
		return null;
	}

	/**
	 * Returns true if the specified page has a following page. This method may
	 * be overriden to implement content-specific page navigation.
	 * 
	 * @param page
	 * @return
	 */
	public boolean hasPrevious(WP page) {
		int idx = pages.indexOf(page);
		return (idx != -1 && (idx > 0));
	}

	/**
	 * Returns the following page to the specified page. This method may be
	 * overriden to implement content-specific page navigation.
	 * 
	 * @param page
	 * @return
	 */
	public WP getPreviousPage(WP page) {
		int idx = pages.indexOf(page);
		if (idx != -1 && (idx > 0)) {
			return pages.get(idx - 1);
		}
		return null;
	}

	/**
	 * Returns the list of pages.
	 * 
	 * @return
	 */
	public final List<WP> getWizardPages() {
		return pages;
	}

	/**
	 * Perform the finish action.
	 * 
	 * @return
	 * @throws ValidationException
	 */
	public abstract boolean performFinish() throws ValidationException;

	/**
	 * The user aborted the wizard.
	 */
	public void performAbort() {
		// nothing to do
	}

	/**
	 * @return Returns the height.
	 */
	public int getHeight() {
		return height;
	}

	/**
	 * @param height
	 *            The height to set.
	 */
	public void setHeight(int height) {
		this.height = height;
	}

	/**
	 * @return Returns the widthHint.
	 */
	public int getWidth() {
		return width;
	}

	/**
	 * @param width
	 *            The width to set.
	 */
	public void setWidth(int width) {
		this.width = width;
	}

	/**
	 * @param currentPage
	 * @return
	 */
	public boolean canFinish(WP currentPage) {
		return !hasNext(currentPage);
	}

}