/*
 * 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.apache.xerces.impl.dv.xs.XSSimpleTypeDecl;
import org.apache.xerces.xni.NamespaceContext;
import org.w3c.dom.DOMException;

AttrNSImpl inherits from AttrImpl and adds namespace support. 

The qualified name is the node name, and we store localName which is also
used in all queries. On the other hand we recompute the prefix when
necessary.
Author:
Arnaud  Le Hors, IBM, Andy Clark, IBM, Ralf Pfeiffer, IBM
@xerces.internal
Version:
$Id: AttrNSImpl.java 924245 2010-03-17 11:58:14Z mrglavas $/**
 * AttrNSImpl inherits from AttrImpl and adds namespace support. 
 * <P>
 * The qualified name is the node name, and we store localName which is also
 * used in all queries. On the other hand we recompute the prefix when
 * necessary.
 * 
 * @xerces.internal

 * 
 * @author Arnaud  Le Hors, IBM
 * @author Andy Clark, IBM
 * @author Ralf Pfeiffer, IBM
 * @version $Id: AttrNSImpl.java 924245 2010-03-17 11:58:14Z mrglavas $
 */
public class AttrNSImpl
    extends AttrImpl {

    //
    // Constants
    //

    
Serialization version. /** Serialization version. */
    static final long serialVersionUID = -781906615369795414L;
    
    static final String xmlnsURI = "http://www.w3.org/2000/xmlns/";
    static final String xmlURI = "http://www.w3.org/XML/1998/namespace";

    //
    // Data
    //

    
DOM2: Namespace URI. /** DOM2: Namespace URI. */
    protected String namespaceURI;
  
    
DOM2: localName. /** DOM2: localName. */
    protected String localName;

    /*
     * Default constructor
     */
    public AttrNSImpl(){}
        
   
DOM2: Constructor for Namespace implementation.
/**
     * DOM2: Constructor for Namespace implementation.
     */
    protected AttrNSImpl(CoreDocumentImpl ownerDocument, 
                         String namespaceURI, 
                         String qualifiedName) {

        super(ownerDocument, qualifiedName);
        setName(namespaceURI, qualifiedName);
    }

    private void setName(String namespaceURI, String qname){
        CoreDocumentImpl ownerDocument = ownerDocument();
        String prefix;
        // DOM Level 3: namespace URI is never empty string.
        this.namespaceURI = namespaceURI;
        if (namespaceURI !=null) {
            this.namespaceURI = (namespaceURI.length() == 0)? null
                    : namespaceURI;
            
        }
        int colon1 = qname.indexOf(':');
        int colon2 = qname.lastIndexOf(':');
        ownerDocument.checkNamespaceWF(qname, colon1, colon2);
        if (colon1 < 0) {
            // there is no prefix
            localName = qname;
            if (ownerDocument.errorChecking) {
                ownerDocument.checkQName(null, localName);
                
                if (qname.equals("xmlns") && (namespaceURI == null
                    || !namespaceURI.equals(NamespaceContext.XMLNS_URI))
                    || (namespaceURI!=null && namespaceURI.equals(NamespaceContext.XMLNS_URI)
                    && !qname.equals("xmlns"))) {
                    String msg =
                        DOMMessageFormatter.formatMessage(
                                DOMMessageFormatter.DOM_DOMAIN,
                                "NAMESPACE_ERR",
                                null);
                    throw new DOMException(DOMException.NAMESPACE_ERR, msg);
                }
            }
        }
        else {
            prefix = qname.substring(0, colon1);
            localName = qname.substring(colon2+1);
            ownerDocument.checkQName(prefix, localName);
            ownerDocument.checkDOMNSErr(prefix, namespaceURI);
        }
    } 

    // when local name is known
    public AttrNSImpl(CoreDocumentImpl ownerDocument, 
                         String namespaceURI, 
                         String qualifiedName,
                         String localName) {
        super(ownerDocument, qualifiedName);
        
        this.localName = localName;
        this.namespaceURI = namespaceURI;
    }
    
    // for DeferredAttrImpl
    protected AttrNSImpl(CoreDocumentImpl ownerDocument, 
                         String value) {
        super(ownerDocument, value);
    }

    // Support for DOM Level 3 renameNode method.
    // Note: This only deals with part of the pb. It is expected to be
    // called after the Attr has been detached for one thing.
    // CoreDocumentImpl does all the work.
    void rename(String namespaceURI, String qualifiedName) {
        if (needsSyncData()) {
            synchronizeData();
        }
		this.name = qualifiedName;
        setName(namespaceURI, qualifiedName);
    }

    //
    // DOM2: Namespace methods
    //

    
Introduced in DOM Level 2. 

The namespace URI of this node, or null if it is unspecified.

This is not a computed value that is the result of a namespace lookup
based on an examination of the namespace declarations in scope. It is
merely the namespace URI given at creation time.

For nodes created with a DOM Level 1 method, such as createElement
from the Document interface, this is null.     
Since:
WD-DOM-Level-2-19990923/** 
     * Introduced in DOM Level 2. <p>
     *
     * The namespace URI of this node, or null if it is unspecified.<p>
     *
     * This is not a computed value that is the result of a namespace lookup
     * based on an examination of the namespace declarations in scope. It is
     * merely the namespace URI given at creation time.<p>
     *
     * For nodes created with a DOM Level 1 method, such as createElement
     * from the Document interface, this is null.     
     * @since WD-DOM-Level-2-19990923
     */
    public String getNamespaceURI()
    {
        if (needsSyncData()) {
            synchronizeData();
        }
        // REVIST: This code could/should be done at a lower-level, such that
        // the namespaceURI is set properly upon creation. However, there still
        // seems to be some DOM spec interpretation grey-area.
        return namespaceURI;
    }
    
    
Introduced in DOM Level 2. 

The namespace prefix of this node, or null if it is unspecified. 

For nodes created with a DOM Level 1 method, such as createElement
from the Document interface, this is null. 

Since:
WD-DOM-Level-2-19990923/** 
     * Introduced in DOM Level 2. <p>
     *
     * The namespace prefix of this node, or null if it is unspecified. <p>
     *
     * For nodes created with a DOM Level 1 method, such as createElement
     * from the Document interface, this is null. <p>
     *
     * @since WD-DOM-Level-2-19990923
     */
    public String getPrefix()
    {
        if (needsSyncData()) {
            synchronizeData();
        }
        int index = name.indexOf(':');
        return index < 0 ? null : name.substring(0, index); 
    }
    
    
Introduced in DOM Level 2. 

Note that setting this attribute changes the nodeName attribute, which
holds the qualified name, as well as the tagName and name attributes of
the Element and Attr interfaces, when applicable.

Params:
prefix – The namespace prefix of this node, or null(empty string) if it is unspecified.
Throws:
INVALID_CHARACTER_ERR – 
                  Raised if the specified
                  prefix contains an invalid character.
DOMException – 
Since:
WD-DOM-Level-2-19990923/**
     * Introduced in DOM Level 2. <p>
     * 
     * Note that setting this attribute changes the nodeName attribute, which
     * holds the qualified name, as well as the tagName and name attributes of
     * the Element and Attr interfaces, when applicable.<p>
     * 
     * @param prefix The namespace prefix of this node, or null(empty string) if it is unspecified.
     *
     * @exception INVALID_CHARACTER_ERR
     *                   Raised if the specified
     *                   prefix contains an invalid character.
     * @exception DOMException
     * @since WD-DOM-Level-2-19990923
     */
    public void setPrefix(String prefix)
        throws DOMException
    {
        if (needsSyncData()) {
            synchronizeData();
        }
        if (ownerDocument().errorChecking) {
            if (isReadOnly()) {
                String msg = DOMMessageFormatter.formatMessage(DOMMessageFormatter.DOM_DOMAIN, "NO_MODIFICATION_ALLOWED_ERR", null);
                throw new DOMException(DOMException.NO_MODIFICATION_ALLOWED_ERR, msg);
            }
            if (prefix != null && prefix.length() != 0) {

                if (!CoreDocumentImpl.isXMLName(prefix,ownerDocument().isXML11Version())) {
                    String msg = DOMMessageFormatter.formatMessage(DOMMessageFormatter.DOM_DOMAIN, "INVALID_CHARACTER_ERR", null);
                    throw new DOMException(DOMException.INVALID_CHARACTER_ERR, msg);
                }
                if (namespaceURI == null || prefix.indexOf(':') >=0) {
                    String msg = DOMMessageFormatter.formatMessage(DOMMessageFormatter.DOM_DOMAIN, "NAMESPACE_ERR", null);
                    throw new DOMException(DOMException.NAMESPACE_ERR, msg);
               
                }
               if (prefix.equals("xmlns")) {
                    if (!namespaceURI.equals(xmlnsURI)){
                        String msg = DOMMessageFormatter.formatMessage(DOMMessageFormatter.DOM_DOMAIN, "NAMESPACE_ERR", null);
                        throw new DOMException(DOMException.NAMESPACE_ERR, msg);
                    }
                } else if (prefix.equals("xml")) {
                    if (!namespaceURI.equals(xmlURI)) {
                        String msg = DOMMessageFormatter.formatMessage(DOMMessageFormatter.DOM_DOMAIN, "NAMESPACE_ERR", null);
                        throw new DOMException(DOMException.NAMESPACE_ERR, msg);
                    }
                }else if (name.equals("xmlns")) {
                    String msg = DOMMessageFormatter.formatMessage(DOMMessageFormatter.DOM_DOMAIN, "NAMESPACE_ERR", null);
                    throw new DOMException(DOMException.NAMESPACE_ERR, msg);
                }
            } 
        }

        // update node name with new qualifiedName
        if (prefix !=null && prefix.length() != 0) {
            name = prefix + ":" + localName;
        }
        else {
            name = localName;
        }
    }
                                        
    
Introduced in DOM Level 2. 

Returns the local part of the qualified name of this node.
Since:
WD-DOM-Level-2-19990923/** 
     * Introduced in DOM Level 2. <p>
     *
     * Returns the local part of the qualified name of this node.
     * @since WD-DOM-Level-2-19990923
     */
    public String getLocalName()
    {
        if (needsSyncData()) {
            synchronizeData();
        }
        return localName;
    }
    
    
    
See Also:
getTypeName.getTypeName()/**
     * @see org.w3c.dom.TypeInfo#getTypeName()
     */
    public String getTypeName() {
        if (type !=null){
            if (type instanceof XSSimpleTypeDecl){
                return ((XSSimpleTypeDecl)type).getName();
            }
            return (String)type;
        }
        return null;
    }

    
Introduced in DOM Level 3. 

Checks if a type is derived from another by restriction. See:
http://www.w3.org/TR/DOM-Level-3-Core/core.html#TypeInfo-isDerivedFrom
Params:
typeNamespaceArg – 
       The namspace of the ancestor type declaration
typeNameArg – 
       The name of the ancestor type declaration
derivationMethod – 
       The derivation method
Returns:
boolean True if the type is derived by restriciton for the
        reference type/**
     * Introduced in DOM Level 3. <p>
     * Checks if a type is derived from another by restriction. See:
     * http://www.w3.org/TR/DOM-Level-3-Core/core.html#TypeInfo-isDerivedFrom
     * 
     * @param typeNamespaceArg 
     *        The namspace of the ancestor type declaration
     * @param typeNameArg
     *        The name of the ancestor type declaration
     * @param derivationMethod
     *        The derivation method
     * 
     * @return boolean True if the type is derived by restriciton for the
     *         reference type
     */
    public boolean isDerivedFrom(String typeNamespaceArg, 
                                 String typeNameArg, 
                                 int derivationMethod) {
        if (type != null) {
            if (type instanceof XSSimpleTypeDecl) {
                return ((XSSimpleTypeDecl) type).isDOMDerivedFrom(
                        typeNamespaceArg, typeNameArg, derivationMethod);
            }    
        } 
        return false;
    }

    
See Also:
getTypeNamespace.getTypeNamespace()/**
     * @see org.w3c.dom.TypeInfo#getTypeNamespace()
     */
    public String getTypeNamespace() {
        if (type !=null) {
            if (type instanceof XSSimpleTypeDecl){
                return ((XSSimpleTypeDecl)type).getNamespace();
            }
            return DTD_URI;
        }
        return null;
    }
    
}