/*
 * 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.util.Enumeration;
import java.util.Hashtable;

/**
 * A base class for all objects in an LX map tree.
 *
 * @author stef@memberwebs.com
 * @version 0.5
 */
public class LXBase
{
    /**
     * Constructs an LXBase object.
     *
     * @param parent The parent object in the LX map tree.
     */
    LXBase(LXBase parent)
    {
        m_name = null;
        m_xmlName = null;
        m_nameSpace = null;
        m_ns = null;
        m_parent = parent;
        m_isUseable = true;

        // If we have a parent and it doesn't have any children set
        // Then give it child capabilities.
        if(parent != null && parent.m_children == null)
            parent.m_children = new Hashtable();
    }

    /**
     * Get the full XML name for this object. This includes any namespace
     * prefixes prepended to the name.
     *
     * @return The XML name.
     */
    public String getXmlName()
    {
        String xmlName = m_xmlName;
        if(xmlName == null)
            xmlName = m_name;

        if(xmlName != null)
        {
            String prefix = getPrefix();
            if(prefix != null)
                xmlName =  prefix + ":" + xmlName;
        }

        return xmlName;
    }


    /**
     * Get the name of this object.
     *
     * @return The name.
     */
    public final String getName()
    {
        return m_name;
    }


    /**
     * Set the name of this object. Updates the parent (if any)
     * to reflect this change in tree structure.
     *
     * @param name The new name
     */
    void setName(String name)
    {
        if(m_name != null && m_parent != null)
            m_parent.m_children.remove(m_name);

        if(name != null)
        {
            if(m_parent != null)
                m_parent.m_children.put(name, this);

            m_name = name;
        }
    }

    /**
     * Get the namespace prefix for this object. If this object has
     * no namespaces info set, returns the parent objects namespace
     * prefix.
     *
     * @return The namespace prefix, or null if there is no prefix.
     */
    public String getPrefix()
    {
        // If we have a namespace then return
        // the ns value regardless
        if(m_nameSpace != null)
            return m_ns;

        if(m_ns != null)
            return m_ns;

        if(m_parent != null)
            return m_parent.getPrefix();

        return null;
    }

    /**
     * Get the full namespace URI for this object.
     *
     * @param here If set to true, then parent namespaces will
     *             be returned if none is set on this object.
     * @return The namespace.
     */
    public String getNamespace(boolean here)
    {
        if(m_nameSpace != null || here)
            return m_nameSpace;

        if(m_parent != null)
            return m_parent.getNamespace();

        return null;
    }

    /**
     * Get the full namespace URI for this node.
     * If this object has no namespace, it's parent will
     * be queried.
     *
     * @return The namespace.
     */
    public String getNamespace()
    {
        return getNamespace(false);
    }

    /**
     * Get this object's parent in the LX map tree.
     *
     * @return The parent, or null if this object has no parent.
     */
    public final LXBase getParent()
    {
        return m_parent;
    }

    /**
     * Get a child of this object in the LX map tree.
     *
     * @param name The child's name.
     * @return The child, or null if no such child is present.
     */
    public final LXBase getChild(String name)
    {
        if(m_children == null)
            return null;

        return (LXBase)m_children.get(name);
    }

    /**
     * Get the names of all the child objects.
     *
     * @return An enumeraton of the child attribute names.
     */
    public final Enumeration getChildNames()
    {
        if(m_children == null)
            return null;

        return m_children.keys();
    }

    /**
     * Check whether this object has been marked unusable.
     *
     * @return Usability status.
     */
    public final boolean isUseable()
    {
        return m_isUseable;
    }

    /**
     * Get the LX hook for this object. If this
     * object has no hook, then the parent will be queried.
     *
     * @return The class name of the LX hook.
     */
    public String getHook()
    {
        if(m_hook == null && m_parent != null)
            return m_parent.getHook();

        return m_hook;
    }

    // The name to be used when creating XML for this object.
    String m_xmlName;

    // Namespace information for this object
    String m_nameSpace;
    String m_ns;

    // The hook for this object and below
    String m_hook;

    // Is this object useable or not
    boolean m_isUseable;

    // This object's parent in the LX map
    private LXBase m_parent;

    // This object's name
    private String m_name;

    // Children in the LX map tree of this object.
    private Hashtable m_children;
};