/*
 *                 Sun Public License Notice
 * 
 * The contents of this file are subject to the Sun Public License
 * Version 1.0 (the "License"). You may not use this file except in
 * compliance with the License. A copy of the License is available at
 * http://www.sun.com/
 * 
 * The Original Code is NetBeans. The Initial Developer of the Original
 * Code is Sun Microsystems, Inc. Portions Copyright 1997-2003 Sun
 * Microsystems, Inc. All Rights Reserved.
 */

package org.netbeans.modules.java.ui.wizard;

import java.io.IOException;
import java.text.MessageFormat;
import java.util.NoSuchElementException;

import java.awt.Component;
import java.awt.event.ActionEvent;
import javax.swing.SwingUtilities;
import javax.swing.event.ChangeListener;

import org.openide.ErrorManager;
import org.openide.WizardDescriptor;
import org.openide.filesystems.FileObject;
import org.openide.loaders.DataObject;
import org.openide.loaders.DataFolder;
import org.openide.loaders.TemplateWizard;
import org.openide.util.Utilities;
import org.openide.util.NbBundle;

import org.openide.src.Type;

import org.netbeans.modules.java.JavaDataLoader;
import org.netbeans.api.java.classpath.ClassPath;

public class JavaWizardIterator implements TemplateWizard.Iterator {
    private static final long serialVersionUID = -1987345873459L;

    /** Array of panels that form the Wizard.
     */
    private transient WizardDescriptor.Panel[] panels;

    /**
     * Names for panels used in the Wizard.
     */
    private static String[] panelNames;
    
    /** Singleton instance of JavaWizardIterator, should it be ever needed.
     */
    private static JavaWizardIterator instance;
    
    /** Index of the current panel. Panels are numbered from 0 to PANEL_COUNT - 1.
     */
    private transient int panelIndex = 0;
    
    /**
     * Holds a reference to the instance of TemplateWizard we are communicating with.
     */
    private transient TemplateWizard wizardInstance;

    public JavaWizardIterator() {
    }
    
    /** Returns JavaWizardIterator singleton instance. This method is used
     * for constructing the instance from filesystem.attributes.
     */
    public static synchronized JavaWizardIterator singleton() {
        if (instance == null) {
            instance = new JavaWizardIterator();
        }
        return instance;
    }
    // ========================= TemplateWizard.Iterator ============================

    /** Instantiates the template using informations provided by
     * the wizard.
     *
     * @param wiz the wizard
     * @return set of data objects that has been created (should contain
     *  at least one
     * @exception IOException if the instantiation fails
    */
    public java.util.Set instantiate(TemplateWizard wiz) throws IOException, IllegalArgumentException {
        DataObject obj = instantiateTemplate(wiz.getTemplate(), wiz.getTargetFolder(), wiz.getTargetName());

        // run default action (hopefully should be here)
        final org.openide.nodes.Node node = obj.getNodeDelegate ();
        final org.openide.util.actions.SystemAction sa = node.getDefaultAction ();
        if (sa != null) {
            SwingUtilities.invokeLater(new Runnable () {
                public void run () {
                    sa.actionPerformed (new ActionEvent (node, ActionEvent.ACTION_PERFORMED, "")); // NOI18N
                }
            });
        }
        return java.util.Collections.singleton(obj);
    }
    
    public WizardDescriptor.Panel current() {
        return panels[panelIndex];
    }
    
    public String name() {
        return ""; // NOI18N
    }
    
    public boolean hasNext() {
        return false;
    }
    
    public boolean hasPrevious() {
        return false;
    }
    
    public void nextPanel() {
        throw new NoSuchElementException();
    }
    
    public void previousPanel() {
        throw new NoSuchElementException();
    }
    
    /** Add a listener to changes of the current panel.
     * The listener is notified when the possibility to move forward/backward changes.
     * @param l the listener to add
    */
    public void addChangeListener(ChangeListener l) {
    }
    
    /** Remove a listener to changes of the current panel.
     * @param l the listener to remove
    */
    public void removeChangeListener(ChangeListener l) {
    }

    public void initialize(TemplateWizard wizard) {
        this.wizardInstance = wizard;
        
	if (panels == null) {
            
            Component panel = wizard.targetChooser().getComponent();
            panelNames = new String[]{panel.getName()};
            if (panel instanceof javax.swing.JComponent) {
                ((javax.swing.JComponent)panel).putClientProperty(
                    "WizardPanel_contentData", panelNames); // NOI18N
            }
            panels = new WizardDescriptor.Panel[] {
                wizardInstance.targetChooser()
            };
	}
    }
    
    public void uninitialize(TemplateWizard wiz) {
	    panels = null;
        wizardInstance = null;
    }

    // ========================= IMPLEMENTATION ============================
    
    private Object readResolve() {
        return singleton();
    }
    
    /** Instantiates the template. Currently it just delegates to the template DataObject's
     * createFromTemplate method.
     */
    private DataObject instantiateTemplate(DataObject tpl, DataFolder target, String name) throws IOException {
        if (name == null) {
            name = getDefaultName(tpl, target);
        }
        
        checkValidPackageName(target);
        checkTargetName(target, name);
        return tpl.createFromTemplate(target, name);
    }
    
    private boolean isValidPackageName(String s) {
        // valid package is an empty one, or well-formed java identifier :-)
        if ("".equals(s)) // NOI18N
            return true;
        try {
            Type t = Type.parse(s);
            return true;
        } catch (IllegalArgumentException ex) {
            return false;
        }
    }
    
    private void checkValidPackageName(DataFolder targetFolder) 
        throws IllegalStateException {
        FileObject folder = targetFolder.getPrimaryFile();
        ClassPath cp = ClassPath.getClassPath(folder,ClassPath.SOURCE);
        String msg = null;
        if (cp != null) {
            String fullTarget = cp.getResourceName(folder, '.',false);
            if (isValidPackageName (fullTarget)) {
                return;
            }
            else {
                msg = MessageFormat.format(getString("FMTERR_IllegalFolderName"), // NOI18N
                    new Object[] {
                    folder.getPath(),
                    fullTarget});
            }
        }
        else {
            msg = getString ("ERR_NotInSourcePath");
        }
        // checking for java-compatible name - both the folder name and the target name
        // must be acceptable.
        throw (IllegalStateException)ErrorManager.getDefault().annotate(
            new IllegalStateException(msg),
            ErrorManager.USER, null, msg,
            null, null);
    }
    
    /** 
     * @param folder target folder for java file
     * @param desiredName name to check
     * @return true if the desiredName is OK
     */ 
    private boolean checkTargetName(DataFolder folder, String desiredName) {
        if (!Utilities.isJavaIdentifier(desiredName)) {
            String msg = MessageFormat.format(getString("FMTERR_IllegalTargetName"), // NOI18N
            new Object[] {
                desiredName
            });
            notifyError(msg);
            return false;
        }
        
        FileObject f = folder.getPrimaryFile();
        // check whether the name already exists:
        if (f.getFileObject(desiredName, JavaDataLoader.JAVA_EXTENSION) != null) {
            String msg = MessageFormat.format(getString("FMTERR_TargetExists"), // NOI18N
            new Object[] {
                desiredName
            });
            notifyError(msg);
            return false;
        }
        return true;
    }
    
    private void notifyError(String msg) {
        this.wizardInstance.putProperty("WizardPanel_errorMessage", msg); //NOI18N
        IllegalStateException ex = new IllegalStateException(msg);
        ErrorManager.getDefault().annotate(ex, ErrorManager.USER, null, msg, null, null);
        throw ex;
    }
    
    private String getDefaultName(DataObject template, DataFolder targetFolder) {
        String desiredName = org.openide.filesystems.FileUtil.findFreeFileName(targetFolder.getPrimaryFile(),
            template.getName(), JavaDataLoader.JAVA_EXTENSION);
        return desiredName;
    }

    static String getString(String key) {
        return NbBundle.getMessage(JavaWizardIterator.class, key);
    }
    
    static char getMnemonic(String key) {
	    return getString(key).charAt(0);
    }
}