/*******************************************************************************
 * Copyright (c) 2006 Sybase, Inc. 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:
 *     Sybase, Inc. - initial API and implementation
 *******************************************************************************/
package org.eclipse.jst.pagedesigner.elementedit;

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

import org.eclipse.jst.jsf.common.dom.TagIdentifier;
import org.eclipse.jst.jsf.core.internal.tld.TagIdentifierFactory;
import org.eclipse.jst.pagedesigner.elementedit.html.HTMLElementEditFactory;
import org.eclipse.jst.pagedesigner.elementedit.jsp.JSPElementEditFactory;
import org.w3c.dom.Element;

/**
 * @author mengbo
 * @version 1.5
 */
public class ElementEditFactoryRegistry {
	List _factories = new ArrayList();

	private static ElementEditFactoryRegistry _instance;

	/**
	 * 
	 */
	private ElementEditFactoryRegistry() {
		addFactory(new HTMLElementEditFactory());
        addFactory(new JSPElementEditFactory());

		List<IElementEditFactory> facs = 
		    ElementEditFacRegistryReader.getAllHandlers();

		if (facs != null) 
		{
			for (IElementEditFactory fac : facs) 
			{
				addFactory(fac);
			}
		}
	}

	/**
	 * Add a factory to list available.
	 * 
	 * @param fac
	 */
	public void addFactory(IElementEditFactory fac) {
		_factories.add(fac);
	}

    /**
     * @param tagIdentifier 
     * @return an IElementEdit constructed for the tag uniquely identified
     * by the ns uri (tag uri for JSP tags) and tagName (element name) or null
     * if the system can't create one.
     */
    public IElementEdit createElementEdit(final TagIdentifier tagIdentifier)
    {
        final String uri = tagIdentifier.getUri();
        
        // first round, match uri
        for (int i = 0, size = _factories.size(); i < size; i++) {
            IElementEditFactory fac = (IElementEditFactory) _factories.get(i);
            String facuri = fac.getSupportedURI();
            if (facuri != null && facuri.equals(uri)) {
                IElementEdit elementEdit = fac.createElementEdit(tagIdentifier);
                if (elementEdit != null) {
                    return elementEdit;
                }
            }
        }
        // second round
        for (int i = 0, size = _factories.size(); i < size; i++) {
            IElementEditFactory fac = (IElementEditFactory) _factories.get(i);
            String facuri = fac.getSupportedURI();
            if (facuri == null) {
                IElementEdit elementEdit = fac.createElementEdit(tagIdentifier);
                if (elementEdit != null) {
                    return elementEdit;
                }
            }
        }
        return null;
    }
    
	/**
     * Convenience method for createElementEdit(uri, tagName) that takes
     * a tag element.
     * 
	 * @param ele
	 * @return an element edit
	 */
	public IElementEdit createElementEdit(Element ele) {
		final TagIdentifier tagIdentifier = TagIdentifierFactory.createDocumentTagWrapper(ele);
        return createElementEdit(tagIdentifier);
	}

	/**
	 * @return the single instance of the factory registry
	 */
	public static ElementEditFactoryRegistry getInstance() {
		if (_instance == null) {
			_instance = new ElementEditFactoryRegistry();
		}
		return _instance;
	}
}