/*******************************************************************************
 * Copyright (c) 2000, 2005 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.internal.dialogs;

import org.eclipse.core.runtime.Assert;
import org.eclipse.jface.wizard.IWizardPage;
import org.eclipse.jface.wizard.Wizard;
import org.eclipse.ui.IWorkingSet;
import org.eclipse.ui.dialogs.IWorkingSetNewWizard;
import org.eclipse.ui.dialogs.IWorkingSetPage;
import org.eclipse.ui.internal.WorkbenchMessages;
import org.eclipse.ui.internal.WorkbenchPlugin;
import org.eclipse.ui.internal.registry.WorkingSetDescriptor;
import org.eclipse.ui.internal.registry.WorkingSetRegistry;

/**
 * A new working set wizard allows the user to create a 
 * new working set using a plugin specified working set page.
 * 
 * @since 2.0
 * @see org.eclipse.ui.dialog.IWorkingSetPage
 */
public class WorkingSetNewWizard extends Wizard implements IWorkingSetNewWizard {
    private WorkingSetTypePage workingSetTypePage;

    private IWorkingSetPage workingSetEditPage;

    private String editPageId;

    private IWorkingSet workingSet;
    
    private WorkingSetDescriptor[] descriptors;
    
    /**
     * Creates a new instance of the receiver.
     * 
     * @param descriptors the choice of descriptors 
     */
    public WorkingSetNewWizard(WorkingSetDescriptor[] descriptors) {
        super();
        Assert.isTrue(descriptors != null && descriptors.length > 0);
        this.descriptors= descriptors;
        setWindowTitle(WorkbenchMessages.WorkingSetNewWizard_title);
    }

    /**
     * Overrides method in Wizard.
     * Adds a page listing the available kinds of working sets.
     * The second wizard page will depend on the selected working set 
     * type.
     * 
     * @see org.eclipse.jface.wizard.Wizard#addPages()
     */
    public void addPages() {
        super.addPages();

        IWizardPage page;
        WorkingSetRegistry registry = WorkbenchPlugin.getDefault().getWorkingSetRegistry();
        
        if (descriptors.length > 1) {
            page = workingSetTypePage = new WorkingSetTypePage();
        } else {
            editPageId = descriptors[0].getId();
            page = workingSetEditPage = registry.getWorkingSetPage(editPageId);
        }
        page.setWizard(this);
        addPage(page);
        setForcePreviousAndNextButtons(descriptors.length > 1);
    }

	/**
     * Overrides method in Wizard.
     * 
     * @see org.eclipse.jface.wizard.Wizard#canFinish()
     */
    public boolean canFinish() {
        return (workingSetEditPage != null && workingSetEditPage
                .isPageComplete());
    }

    /**
     * Overrides method in Wizard.
     * Returns a working set page for creating the new working set.
     * This second page is loaded from the plugin that defined the
     * selected working set type.
     * 
     * @see org.eclipse.jface.wizard.Wizard#getNextPage(IWizardPage)
     */
    public IWizardPage getNextPage(IWizardPage page) {
        if (workingSetTypePage != null && page == workingSetTypePage) {
            String pageId = workingSetTypePage.getSelection();
            if (pageId != null) {
                if (workingSetEditPage == null || pageId != editPageId) {
                    WorkingSetRegistry registry = WorkbenchPlugin.getDefault()
                            .getWorkingSetRegistry();
                    workingSetEditPage = registry.getWorkingSetPage(pageId);
                    addPage(workingSetEditPage);
                    editPageId = pageId;
                }
                return workingSetEditPage;
            }
        }
        return null;
    }

    /**
     * Returns the new working set. Returns null if the wizard has 
     * been cancelled.
     * 
     * @return the new working set or null if the wizard has been 
     * 	cancelled.
     */
    public IWorkingSet getSelection() {
        return workingSet;
    }

    /**
     * Overrides method in Wizard.
     * Stores the newly created working set and the id of the page
     * used to create it.
     * 
     * @see org.eclipse.jface.wizard.Wizard#performFinish()
     */
    public boolean performFinish() {
        workingSetEditPage.finish();
        workingSet = workingSetEditPage.getSelection();
        workingSet.setId(editPageId);
        return true;
    }    
}