/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.xerces.dom;

import org.w3c.dom.Entity;
import org.w3c.dom.Node;

/**
 * Entity nodes hold the reference data for an XML Entity -- either
 * parsed or unparsed. The nodeName (inherited from Node) will contain
 * the name (if any) of the Entity. Its data will be contained in the
 * Entity's children, in exactly the structure which an
 * EntityReference to this name will present within the document's
 * body.
 * <P>
 * Note that this object models the actual entity, _not_ the entity
 * declaration or the entity reference.
 * <P>
 * An XML processor may choose to completely expand entities before
 * the structure model is passed to the DOM; in this case, there will
 * be no EntityReferences in the DOM tree.
 * <P>
 * Quoting the 10/01 DOM Proposal,
 * <BLOCKQUOTE>
 * "The DOM Level 1 does not support editing Entity nodes; if a user
 * wants to make changes to the contents of an Entity, every related
 * EntityReference node has to be replaced in the structure model by
 * a clone of the Entity's contents, and then the desired changes
 * must be made to each of those clones instead. All the
 * descendants of an Entity node are readonly."
 * </BLOCKQUOTE>
 * I'm interpreting this as: It is the parser's responsibilty to call
 * the non-DOM operation setReadOnly(true,true) after it constructs
 * the Entity. Since the DOM explicitly decided not to deal with this,
 * _any_ answer will involve a non-DOM operation, and this is the
 * simplest solution.
 * 
 * @xerces.internal
 * 
 * @author Elena Litani, IBM
 * @version $Id$
 * @since PR-DOM-Level-1-19980818.
 */
public class EntityImpl 
    extends ParentNode
    implements Entity {

    //
    // Constants
    //

    /** Serialization version. */
    static final long serialVersionUID = -3575760943444303423L;
    
    //
    // Data
    //

    /** Entity name. */
    protected String name;

    /** Public identifier. */
    protected String publicId;

    /** System identifier. */
    protected String systemId;

    /** Encoding */
    protected String encoding;


    /** Input Encoding */
    protected String inputEncoding;
    
    /** Version */
    protected String version;


    /** Notation name. */
    protected String notationName;

    /** base uri*/
    protected String baseURI;

    //
    // Constructors
    //

    /** Factory constructor. */
    public EntityImpl(CoreDocumentImpl ownerDoc, String name) {
    	super(ownerDoc);
        this.name = name;
        isReadOnly(true);
    }
    
    //
    // Node methods
    //

    /** 
     * A short integer indicating what type of node this is. The named
     * constants for this value are defined in the org.w3c.dom.Node interface.
     */
    public short getNodeType() {
        return Node.ENTITY_NODE;
    }

    /**
     * Returns the entity name
     */
    public String getNodeName() {
        if (needsSyncData()) {
            synchronizeData();
        }
        return name;
    }

    /** Clone node. */
    public Node cloneNode(boolean deep) {
        EntityImpl newentity = (EntityImpl)super.cloneNode(deep);
        newentity.setReadOnly(true, deep);
        return newentity;
    }

    //
    // Entity methods
    //

    /** 
     * The public identifier associated with the entity. If not specified,
     * this will be null. 
     */
    public String getPublicId() {
        
        if (needsSyncData()) {
            synchronizeData();
        }
        return publicId;

    } // getPublicId():String

    /** 
     * The system identifier associated with the entity. If not specified,
     * this will be null. 
     */
    public String getSystemId() {

        if (needsSyncData()) {
            synchronizeData();
        }
        return systemId;

    } // getSystemId():String

    /** 
      * DOM Level 3 WD - experimental
      * the version number of this entity, when it is an external parsed entity. 
      */
    public String getXmlVersion() {

       if (needsSyncData()) {
           synchronizeData();
       }
       return version;

   } // getVersion():String


    /**
     * DOM Level 3 WD - experimental 
     * the encoding of this entity, when it is an external parsed entity. 
     */
    public String getXmlEncoding() {

       if (needsSyncData()) {
           synchronizeData();
       }

       return encoding;

   } // getVersion():String





    /** 
     * Unparsed entities -- which contain non-XML data -- have a
     * "notation name" which tells applications how to deal with them.
     * Parsed entities, which <em>are</em> in XML format, don't need this and
     * set it to null.  
     */
    public String getNotationName() {

        if (needsSyncData()) {
            synchronizeData();
        }
        return notationName;

    } // getNotationName():String

    //
    // Public methods
    //

    /**
     * DOM Level 2: The public identifier associated with the entity. If not specified,
     * this will be null. */
    public void setPublicId(String id) {
        
        if (needsSyncData()) {
            synchronizeData();
        }
    	publicId = id;

    } // setPublicId(String)

    /**
     * NON-DOM 
     * encoding - An attribute specifying, as part of the text declaration, 
     * the encoding of this entity, when it is an external parsed entity. 
     * This is null otherwise
     *
     */
    public void setXmlEncoding(String value) {
        if (needsSyncData()) {
            synchronizeData();
        }
        encoding = value;
    } // setEncoding (String)


    /**
     * An attribute specifying the encoding used for this entity at the tiome 
     * of parsing, when it is an external parsed entity. This is 
     * <code>null</code> if it an entity from the internal subset or if it 
     * is not known..
     * @since DOM Level 3
     */
    public String getInputEncoding(){
        if (needsSyncData()) {
            synchronizeData();
        }
        return inputEncoding;
    }
    
    /**
     * NON-DOM, used to set the input encoding.
     */
    public void setInputEncoding(String inputEncoding){
        if (needsSyncData()) {
            synchronizeData();
        }
        this.inputEncoding = inputEncoding;
    }

    /** 
      * NON-DOM
      * version - An attribute specifying, as part of the text declaration, 
      * the version number of this entity, when it is an external parsed entity. 
      * This is null otherwise
      */
    public void setXmlVersion(String value) {       
        if (needsSyncData()) {
            synchronizeData();
        }
        version = value;
    } // setVersion (String)


    /**
     * DOM Level 2: The system identifier associated with the entity. If not
     * specified, this will be null. 
     */
    public void setSystemId(String id) {
        if (needsSyncData()) {
            synchronizeData();
        }
    	systemId = id;

    } // setSystemId(String)

    /** 
     * DOM Level 2: Unparsed entities -- which contain non-XML data -- have a
     * "notation name" which tells applications how to deal with them.
     * Parsed entities, which <em>are</em> in XML format, don't need this and
     * set it to null.  
     */
    public void setNotationName(String name) {        
        if (needsSyncData()) {
            synchronizeData();
        }
    	notationName = name;

    } // setNotationName(String)
    


    /**
     * Returns the absolute base URI of this node or null if the implementation
     * wasn't able to obtain an absolute URI. Note: If the URI is malformed, a
     * null is returned.
     * 
     * @return The absolute base URI of this node or null.
     * @since DOM Level 3
     */
    public String getBaseURI() {

        if (needsSyncData()) {
            synchronizeData();
        }
        return (baseURI!=null)?baseURI:((CoreDocumentImpl)getOwnerDocument()).getBaseURI();
    }

    /** NON-DOM: set base uri*/
    public void setBaseURI(String uri){
        if (needsSyncData()) {
            synchronizeData();
        }
        baseURI = uri;
    }



} // class EntityImpl
