/*

 * 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.

 */

/*

 * Copyright (c) 2005, Oracle and/or its affiliates. All rights reserved.

 */

package org.jcp.xml.dsig.internal.dom;

import java.security.Provider;

import java.util.ArrayList;

import java.util.Collections;

import java.util.List;

import javax.xml.crypto.MarshalException;

import javax.xml.crypto.XMLCryptoContext;

import javax.xml.crypto.XMLStructure;

import javax.xml.crypto.dom.DOMCryptoContext;

import javax.xml.crypto.dsig.XMLSignature;

import javax.xml.crypto.dsig.dom.DOMSignContext;

import javax.xml.crypto.dsig.keyinfo.KeyInfo;

import org.w3c.dom.Attr;

import org.w3c.dom.Document;

import org.w3c.dom.Element;

import org.w3c.dom.Node;

/**

 * DOM-based implementation of KeyInfo.

 *

 */

public final class DOMKeyInfo extends DOMStructure implements KeyInfo {

    private final String id;

    private final List<XMLStructure> keyInfoTypes;

    /**

     * A utility function to suppress casting warnings.

     * @param ki

     * @return the content of a KeyInfo Object

     */

    @SuppressWarnings("unchecked")

    public static List<XMLStructure> getContent(KeyInfo ki) {

        return ki.getContent();

    }

    /**

     * Creates a {@code DOMKeyInfo}.

     *

     * @param content a list of one or more {@link XMLStructure}s representing

     *    key information types. The list is defensively copied to protect

     *    against subsequent modification.

     * @param id an ID attribute

     * @throws NullPointerException if {@code content} is {@code null}

     * @throws IllegalArgumentException if {@code content} is empty

     * @throws ClassCastException if {@code content} contains any entries

     *    that are not of type {@link XMLStructure}

     */

    public DOMKeyInfo(List<? extends XMLStructure> content, String id) {

        if (content == null) {

            throw new NullPointerException("content cannot be null");

        }

        this.keyInfoTypes =

            Collections.unmodifiableList(new ArrayList<>(content));

        if (this.keyInfoTypes.isEmpty()) {

            throw new IllegalArgumentException("content cannot be empty");

        }

        for (int i = 0, size = this.keyInfoTypes.size(); i < size; i++) {

            if (!(this.keyInfoTypes.get(i) instanceof XMLStructure)) {

                throw new ClassCastException

                    ("content["+i+"] is not a valid KeyInfo type");

            }

        }

        this.id = id;

    }

    /**

     * Creates a {@code DOMKeyInfo} from XML.

     *

     * @param kiElem KeyInfo element

     */

    public DOMKeyInfo(Element kiElem, XMLCryptoContext context,

                      Provider provider)

        throws MarshalException

    {

        // get Id attribute, if specified

        Attr attr = kiElem.getAttributeNodeNS(null, "Id");

        if (attr != null) {

            id = attr.getValue();

            kiElem.setIdAttributeNode(attr, true);

        } else {

            id = null;

        }

        // get all children nodes

        List<XMLStructure> content = new ArrayList<>();

        Node firstChild = kiElem.getFirstChild();

        if (firstChild == null) {

            throw new MarshalException("KeyInfo must contain at least one type");

        }

        while (firstChild != null) {

            if (firstChild.getNodeType() == Node.ELEMENT_NODE) {

                Element childElem = (Element)firstChild;

                String localName = childElem.getLocalName();

                String namespace = childElem.getNamespaceURI();

                if ("X509Data".equals(localName) && XMLSignature.XMLNS.equals(namespace)) {

                    content.add(new DOMX509Data(childElem));

                } else if ("KeyName".equals(localName) && XMLSignature.XMLNS.equals(namespace)) {

                    content.add(new DOMKeyName(childElem));

                } else if ("KeyValue".equals(localName) && XMLSignature.XMLNS.equals(namespace)) {

                    content.add(DOMKeyValue.unmarshal(childElem));

                } else if ("RetrievalMethod".equals(localName) && XMLSignature.XMLNS.equals(namespace)) {

                    content.add(new DOMRetrievalMethod(childElem,

                                                       context, provider));

                } else if ("PGPData".equals(localName) && XMLSignature.XMLNS.equals(namespace)) {

                    content.add(new DOMPGPData(childElem));

                } else { //may be MgmtData, SPKIData or element from other namespace

                    content.add(new javax.xml.crypto.dom.DOMStructure(childElem));

                }

            }

            firstChild = firstChild.getNextSibling();

        }

        keyInfoTypes = Collections.unmodifiableList(content);

    }

    public String getId() {

        return id;

    }

    public List<XMLStructure> getContent() {

        return keyInfoTypes;

    }

    public void marshal(XMLStructure parent, XMLCryptoContext context)

        throws MarshalException

    {

        if (parent == null) {

            throw new NullPointerException("parent is null");

        }

        if (!(parent instanceof javax.xml.crypto.dom.DOMStructure)) {

            throw new ClassCastException("parent must be of type DOMStructure");

        }

        Node pNode = ((javax.xml.crypto.dom.DOMStructure)parent).getNode();

        String dsPrefix = DOMUtils.getSignaturePrefix(context);

        Element kiElem = DOMUtils.createElement

            (DOMUtils.getOwnerDocument(pNode), "KeyInfo",

             XMLSignature.XMLNS, dsPrefix);

        if (dsPrefix == null || dsPrefix.length() == 0) {

            kiElem.setAttributeNS("http://www.w3.org/2000/xmlns/",

                                  "xmlns", XMLSignature.XMLNS);

        } else {

            kiElem.setAttributeNS("http://www.w3.org/2000/xmlns/",

                                  "xmlns:" + dsPrefix, XMLSignature.XMLNS);

        }

        Node nextSibling = null;

        if (context instanceof DOMSignContext) {

            nextSibling = ((DOMSignContext)context).getNextSibling();

        }

        marshal(pNode, kiElem, nextSibling, dsPrefix, (DOMCryptoContext)context);

    }

    @Override

    public void marshal(Node parent, String dsPrefix,

                        DOMCryptoContext context)

        throws MarshalException

    {

        marshal(parent, null, dsPrefix, context);

    }

    public void marshal(Node parent, Node nextSibling, String dsPrefix,

                        DOMCryptoContext context)

        throws MarshalException

    {

        Document ownerDoc = DOMUtils.getOwnerDocument(parent);

        Element kiElem = DOMUtils.createElement(ownerDoc, "KeyInfo",

                                                XMLSignature.XMLNS, dsPrefix);

        marshal(parent, kiElem, nextSibling, dsPrefix, context);

    }

    private void marshal(Node parent, Element kiElem, Node nextSibling,

                         String dsPrefix, DOMCryptoContext context)

        throws MarshalException

    {

        // create and append KeyInfoType elements

        for (XMLStructure kiType : keyInfoTypes) {

            if (kiType instanceof DOMStructure) {

                ((DOMStructure)kiType).marshal(kiElem, dsPrefix, context);

            } else {

                DOMUtils.appendChild(kiElem,

                    ((javax.xml.crypto.dom.DOMStructure)kiType).getNode());

            }

        }

        // append id attribute

        DOMUtils.setAttributeID(kiElem, "Id", id);

        parent.insertBefore(kiElem, nextSibling);

    }

    @Override

    public boolean equals(Object o) {

        if (this == o) {

            return true;

        }

        if (!(o instanceof KeyInfo)) {

            return false;

        }

        KeyInfo oki = (KeyInfo)o;

        boolean idsEqual = id == null ? oki.getId() == null

                                       : id.equals(oki.getId());

        return keyInfoTypes.equals(oki.getContent()) && idsEqual;

    }

    @Override

    public int hashCode() {

        int result = 17;

        if (id != null) {

            result = 31 * result + id.hashCode();

        }

        result = 31 * result + keyInfoTypes.hashCode();

        return result;

    }

}