/*

 * 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.transforms.implementations;

import java.io.ByteArrayOutputStream;

import java.io.IOException;

import java.io.OutputStream;

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

import com.sun.org.apache.xml.internal.security.c14n.implementations.Canonicalizer20010315;

import com.sun.org.apache.xml.internal.security.c14n.implementations.Canonicalizer20010315OmitComments;

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

import com.sun.org.apache.xml.internal.security.transforms.TransformSpi;

import com.sun.org.apache.xml.internal.security.transforms.Transforms;

import org.w3c.dom.Element;

/**

 * Implements the {@code http://www.w3.org/TR/2001/REC-xml-c14n-20010315}

 * transform.

 *

 */

public class TransformC14N extends TransformSpi {

    /**

     * {@inheritDoc}

     */

    @Override

    protected String engineGetURI() {

        return Transforms.TRANSFORM_C14N_OMIT_COMMENTS;

    }

    /**

     * {@inheritDoc}

     */

    @Override

    protected XMLSignatureInput enginePerformTransform(

        XMLSignatureInput input, OutputStream os, Element transformElement,

        String baseURI, boolean secureValidation

    ) throws CanonicalizationException {

        Canonicalizer20010315 c14n = getCanonicalizer();

        if (os == null) {

            try (ByteArrayOutputStream writer = new ByteArrayOutputStream()) {

                c14n.engineCanonicalize(input, writer, secureValidation);

                writer.flush();

                XMLSignatureInput output = new XMLSignatureInput(writer.toByteArray());

                output.setSecureValidation(secureValidation);

                return output;

            } catch (IOException ex) {

                throw new CanonicalizationException("empty", new Object[] {ex.getMessage()});

            }

        } else {

            c14n.engineCanonicalize(input, os, secureValidation);

            XMLSignatureInput output = new XMLSignatureInput((byte[])null);

            output.setSecureValidation(secureValidation);

            output.setOutputStream(os);

            return output;

        }

    }

    protected Canonicalizer20010315 getCanonicalizer() {

        return new Canonicalizer20010315OmitComments();

    }

}