/*
 * 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.
/**
 * 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.
 */
/*
 * Copyright (c) 2005, 2018, Oracle and/or its affiliates. All rights reserved.
 */
/*
 * $Id: ApacheTransform.java 1788465 2017-03-24 15:10:51Z coheigea $
 */
package org.jcp.xml.dsig.internal.dom;

import java.io.OutputStream;
import java.security.InvalidAlgorithmParameterException;
import java.security.spec.AlgorithmParameterSpec;
import java.util.Set;

import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import com.sun.org.apache.xml.internal.security.signature.XMLSignatureInput;
import com.sun.org.apache.xml.internal.security.transforms.Transform;

import javax.xml.crypto.*;
import javax.xml.crypto.dom.DOMCryptoContext;
import javax.xml.crypto.dsig.*;
import javax.xml.crypto.dsig.spec.TransformParameterSpec;

This is a wrapper/glue class which invokes the Apache XML-Security
Transform.
/**
 * This is a wrapper/glue class which invokes the Apache XML-Security
 * Transform.
 *
 */
public abstract class ApacheTransform extends TransformService {

    static {
        com.sun.org.apache.xml.internal.security.Init.init();
    }

    private static final com.sun.org.slf4j.internal.Logger LOG =
        com.sun.org.slf4j.internal.LoggerFactory.getLogger(ApacheTransform.class);
    private Transform apacheTransform;
    protected Document ownerDoc;
    protected Element transformElem;
    protected TransformParameterSpec params;

    @Override
    public final AlgorithmParameterSpec getParameterSpec() {
        return params;
    }

    public void init(XMLStructure parent, XMLCryptoContext context)
        throws InvalidAlgorithmParameterException
    {
        if (context != null && !(context instanceof DOMCryptoContext)) {
            throw new ClassCastException
                ("context must be of type DOMCryptoContext");
        }
        if (parent == null) {
            throw new NullPointerException();
        }
        if (!(parent instanceof javax.xml.crypto.dom.DOMStructure)) {
            throw new ClassCastException("parent must be of type DOMStructure");
        }
        transformElem = (Element)
            ((javax.xml.crypto.dom.DOMStructure) parent).getNode();
        ownerDoc = DOMUtils.getOwnerDocument(transformElem);
    }

    public void marshalParams(XMLStructure parent, XMLCryptoContext context)
        throws MarshalException
    {
        if (context != null && !(context instanceof DOMCryptoContext)) {
            throw new ClassCastException
                ("context must be of type DOMCryptoContext");
        }
        if (parent == null) {
            throw new NullPointerException();
        }
        if (!(parent instanceof javax.xml.crypto.dom.DOMStructure)) {
            throw new ClassCastException("parent must be of type DOMStructure");
        }
        transformElem = (Element)
            ((javax.xml.crypto.dom.DOMStructure) parent).getNode();
        ownerDoc = DOMUtils.getOwnerDocument(transformElem);
    }

    public Data transform(Data data, XMLCryptoContext xc)
        throws TransformException
    {
        if (data == null) {
            throw new NullPointerException("data must not be null");
        }
        return transformIt(data, xc, null);
    }

    public Data transform(Data data, XMLCryptoContext xc, OutputStream os)
        throws TransformException
    {
        if (data == null) {
            throw new NullPointerException("data must not be null");
        }
        if (os == null) {
            throw new NullPointerException("output stream must not be null");
        }
        return transformIt(data, xc, os);
    }

    private Data transformIt(Data data, XMLCryptoContext xc, OutputStream os)
        throws TransformException
    {
        if (ownerDoc == null) {
            throw new TransformException("transform must be marshalled");
        }

        if (apacheTransform == null) {
            try {
                apacheTransform =
                    new Transform(ownerDoc, getAlgorithm(), transformElem.getChildNodes());
                apacheTransform.setElement(transformElem, xc.getBaseURI());
                boolean secVal = Utils.secureValidation(xc);
                apacheTransform.setSecureValidation(secVal);
                LOG.debug("Created transform for algorithm: {}", getAlgorithm());
            } catch (Exception ex) {
                throw new TransformException("Couldn't find Transform for: " +
                                             getAlgorithm(), ex);
            }
        }

        if (Utils.secureValidation(xc)) {
            String algorithm = getAlgorithm();
            if (Policy.restrictAlg(algorithm)) {
                throw new TransformException(
                    "Transform " + algorithm + " is forbidden when secure validation is enabled"
                );
            }
        }

        XMLSignatureInput in;
        if (data instanceof ApacheData) {
            LOG.debug("ApacheData = true");
            in = ((ApacheData)data).getXMLSignatureInput();
        } else if (data instanceof NodeSetData) {
            LOG.debug("isNodeSet() = true");
            if (data instanceof DOMSubTreeData) {
                LOG.debug("DOMSubTreeData = true");
                DOMSubTreeData subTree = (DOMSubTreeData)data;
                in = new XMLSignatureInput(subTree.getRoot());
                in.setExcludeComments(subTree.excludeComments());
            } else {
                @SuppressWarnings("unchecked")
                Set<Node> nodeSet =
                    Utils.toNodeSet(((NodeSetData)data).iterator());
                in = new XMLSignatureInput(nodeSet);
            }
        } else {
            LOG.debug("isNodeSet() = false");
            try {
                in = new XMLSignatureInput
                    (((OctetStreamData)data).getOctetStream());
            } catch (Exception ex) {
                throw new TransformException(ex);
            }
        }
        boolean secVal = Utils.secureValidation(xc);
        in.setSecureValidation(secVal);

        try {
            if (os != null) {
                in = apacheTransform.performTransform(in, os);
                if (!in.isNodeSet() && !in.isElement()) {
                    return null;
                }
            } else {
                in = apacheTransform.performTransform(in);
            }
            if (in.isOctetStream()) {
                return new ApacheOctetStreamData(in);
            } else {
                return new ApacheNodeSetData(in);
            }
        } catch (Exception ex) {
            throw new TransformException(ex);
        }
    }

    public final boolean isFeatureSupported(String feature) {
        if (feature == null) {
            throw new NullPointerException();
        } else {
            return false;
        }
    }
}