/*
 * Copyright (c) 2004, Stefan Walter
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *     * Redistributions of source code must retain the above
 *       copyright notice, this list of conditions and the
 *       following disclaimer.
 *     * Redistributions in binary form must reproduce the
 *       above copyright notice, this list of conditions and
 *       the following disclaimer in the documentation and/or
 *       other materials provided with the distribution.
 *     * The names of contributors to this software may not be
 *       used to endorse or promote products derived from this
 *       software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
 * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
 * DAMAGE.
 *
 *
 * CONTRIBUTORS
 *  Stef Walter <stef@memberwebs.com>
 *
 */

package com.memberwebs.ldapxml.map;

import java.io.IOException;
import java.util.Map;
import java.util.Set;

import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;
import org.xml.sax.helpers.XMLReaderFactory;


/**
 * The in memory representation of an LX map.
 *
 * @author stef@memberwebs.com
 * @version 0.5
 */
public class LXMap
	extends LXBase
{
	// Cache of the name map
	private Map m_nameMap;

	// Cache of the name set
	private Set m_nameSet;

	// Whether to use the nameset or not
	boolean m_hasInclusive;

	/**
     * Constructs a new LXMap object.
     */
    LXMap(Map nameMap, Set nameSet)
    {
    	super(null);
        m_nameMap = nameMap;
        m_nameSet = nameSet;
        m_hasInclusive = false;
    }


	/**
	 * Get an entry in this LX map by name.
	 *
	 * @param name The entry name.
	 * @return The entry, or null if no such entry is present
	 */
	public LXEntry getEntry(String name)
	{
		LXEntry entry = (LXEntry)getChild(name);

		if(entry != null && !entry.isUseable())
			entry = null;

		return entry;
	}

    /**
     * Get public (XML) to private (LDAP) name mappings
     * for the first entry.
     *
     * @return The name map.
     */
    public final Map getNameMap()
    {
        return m_nameMap;
    }

    /**
     * Get the minimum set of LDAP attributes required
     * to retrieve items via this map.
     */
    public final Set getNameSet()
    {
        return m_hasInclusive ? null : m_nameSet;
    }

	/**
	 * Load an LX map from an XML data stream
	 *
	 * @param source The source of the XML data.
	 */
	public static LXMap loadMap(InputSource source)
			throws LXMapException, IOException
	{
		try
		{
			XMLReader xr = XMLReaderFactory.createXMLReader("org.apache.xerces.parsers.SAXParser");

			// We require some form of validation on the document
			// as our internal checks are lax
			xr.setFeature("http://xml.org/sax/features/validation", true);

			// Parse and load the map.
			LXSAXHandler handler = new LXSAXHandler();
			xr.setContentHandler(handler);
			xr.setErrorHandler(handler);
			xr.parse(source);

			LXMap map = handler.getMap();
			return map;
		}
		catch(SAXException e)
		{
			Exception inside = e.getException();

			if(inside != null)
			{
				inside.printStackTrace();
				if(inside instanceof LXMapException)
					throw (LXMapException)inside;
				else if(inside.getMessage() != null)
					throw new LXMapException(inside.getMessage());
				else
					throw new LXMapException(inside.getClass().getName());
			}

			throw new LXMapException(e.getMessage());
		}
	}

	/**
	 * Load an LX map from a uri.
	 *
	 * @param uri The fully qualified uri of the file.
	 */
	public static LXMap loadMap(String uri)
			throws LXMapException, IOException
	{
		return loadMap(new InputSource(uri));
	}
}