/*

 * reserved comment block

 * DO NOT REMOVE OR ALTER!

 */

/**

 * 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 com.sun.org.apache.xml.internal.security.c14n.implementations;

import java.io.IOException;

import java.io.OutputStream;

import java.util.Map;

import java.util.Set;

import java.util.SortedSet;

import java.util.TreeSet;

import javax.xml.parsers.ParserConfigurationException;

import com.sun.org.apache.xml.internal.security.c14n.CanonicalizationException;

import com.sun.org.apache.xml.internal.security.c14n.Canonicalizer;

import com.sun.org.apache.xml.internal.security.signature.XMLSignatureInput;

import org.w3c.dom.Attr;

import org.w3c.dom.Comment;

import org.w3c.dom.DOMException;

import org.w3c.dom.Element;

import org.w3c.dom.NamedNodeMap;

import org.w3c.dom.Node;

import org.w3c.dom.ProcessingInstruction;

import org.xml.sax.SAXException;

/**

 * Serializes the physical representation of the subtree. All the attributes

 * present in the subtree are emitted. The attributes are sorted within an element,

 * with the namespace declarations appearing before the regular attributes.

 * This algorithm is not a true canonicalization since equivalent subtrees

 * may produce different output. It is therefore unsuitable for digital signatures.

 * This same property makes it ideal for XML Encryption Syntax and Processing,

 * because the decrypted XML content will share the same physical representation

 * as the original XML content that was encrypted.

 */

public class CanonicalizerPhysical extends CanonicalizerBase {

    /**

     * Constructor Canonicalizer20010315

     */

    public CanonicalizerPhysical() {

        super(true);

    }

    /**

     * Always throws a CanonicalizationException.

     *

     * @param xpathNodeSet

     * @param inclusiveNamespaces

     * @return none it always fails

     * @throws CanonicalizationException always

     */

    public byte[] engineCanonicalizeXPathNodeSet(Set<Node> xpathNodeSet, String inclusiveNamespaces)

        throws CanonicalizationException {

        /** $todo$ well, should we throw UnsupportedOperationException ? */

        throw new CanonicalizationException("c14n.Canonicalizer.UnsupportedOperation");

    }

    /**

     * Always throws a CanonicalizationException.

     *

     * @param rootNode

     * @param inclusiveNamespaces

     * @return none it always fails

     * @throws CanonicalizationException

     */

    public byte[] engineCanonicalizeSubTree(Node rootNode, String inclusiveNamespaces)

        throws CanonicalizationException {

        /** $todo$ well, should we throw UnsupportedOperationException ? */

        throw new CanonicalizationException("c14n.Canonicalizer.UnsupportedOperation");

    }

    /**

     * Always throws a CanonicalizationException.

     *

     * @param rootNode

     * @param inclusiveNamespaces

     * @return none it always fails

     * @throws CanonicalizationException

     */

    public byte[] engineCanonicalizeSubTree(

            Node rootNode, String inclusiveNamespaces, boolean propagateDefaultNamespace)

            throws CanonicalizationException {

        /** $todo$ well, should we throw UnsupportedOperationException ? */

        throw new CanonicalizationException("c14n.Canonicalizer.UnsupportedOperation");

    }

    /**

     * Output the Attr[]s for the given element.

     * <br>

     * The code of this method is a copy of {@link #outputAttributes(Element,

     * NameSpaceSymbTable, Map<String, byte[]>)},

     * whereas it takes into account that subtree-c14n is -- well -- subtree-based.

     * So if the element in question isRoot of c14n, it's parent is not in the

     * node set, as well as all other ancestors.

     *

     * @param element

     * @param ns

     * @param cache

     * @throws CanonicalizationException, DOMException, IOException

     */

    @Override

    protected void outputAttributesSubtree(Element element, NameSpaceSymbTable ns,

                                           Map<String, byte[]> cache)

        throws CanonicalizationException, DOMException, IOException {

        if (element.hasAttributes()) {

            // result will contain all the attrs declared directly on that element

            SortedSet<Attr> result = new TreeSet<Attr>(COMPARE);

            NamedNodeMap attrs = element.getAttributes();

            int attrsLength = attrs.getLength();

            for (int i = 0; i < attrsLength; i++) {

                Attr attribute = (Attr) attrs.item(i);

                result.add(attribute);

            }

            OutputStream writer = getWriter();

            //we output all Attrs which are available

            for (Attr attr : result) {

                outputAttrToWriter(attr.getNodeName(), attr.getNodeValue(), writer, cache);

            }

        }

    }

    @Override

    protected void outputAttributes(Element element, NameSpaceSymbTable ns,

                                    Map<String, byte[]> cache)

        throws CanonicalizationException, DOMException, IOException {

        /** $todo$ well, should we throw UnsupportedOperationException ? */

        throw new CanonicalizationException("c14n.Canonicalizer.UnsupportedOperation");

    }

    protected void circumventBugIfNeeded(XMLSignatureInput input)

        throws CanonicalizationException, ParserConfigurationException, IOException, SAXException {

        // nothing to do

    }

    @Override

    protected void handleParent(Element e, NameSpaceSymbTable ns) {

        // nothing to do

    }

    /** {@inheritDoc} */

    public final String engineGetURI() {

        return Canonicalizer.ALGO_ID_C14N_PHYSICAL;

    }

    /** {@inheritDoc} */

    public final boolean engineGetIncludeComments() {

        return true;

    }

    @Override

    protected void outputPItoWriter(ProcessingInstruction currentPI,

                                    OutputStream writer, int position) throws IOException {

        // Processing Instructions before or after the document element are not treated specially

        super.outputPItoWriter(currentPI, writer, NODE_NOT_BEFORE_OR_AFTER_DOCUMENT_ELEMENT);

    }

    @Override

    protected void outputCommentToWriter(Comment currentComment,

                                         OutputStream writer, int position) throws IOException {

        // Comments before or after the document element are not treated specially

        super.outputCommentToWriter(currentComment, writer, NODE_NOT_BEFORE_OR_AFTER_DOCUMENT_ELEMENT);

    }

}