/*

 * Copyright (c) 2000, 2014, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package javax.imageio.metadata;

import java.util.ArrayList;

import java.util.Iterator;

import java.util.List;

import org.w3c.dom.Attr;

import org.w3c.dom.Document;

import org.w3c.dom.Element;

import org.w3c.dom.DOMException;

import org.w3c.dom.NamedNodeMap;

import org.w3c.dom.Node;

import org.w3c.dom.NodeList;

import org.w3c.dom.TypeInfo;

import org.w3c.dom.UserDataHandler;

class IIODOMException extends DOMException {

    private static final long serialVersionUID = -4369510142067447468L;

    public IIODOMException(short code, String message) {

        super(code, message);

    }

}

class IIONamedNodeMap implements NamedNodeMap {

    List<? extends Node> nodes;

    public IIONamedNodeMap(List<? extends Node> nodes) {

        this.nodes = nodes;

    }

    public int getLength() {

        return nodes.size();

    }

    public Node getNamedItem(String name) {

        Iterator<? extends Node> iter = nodes.iterator();

        while (iter.hasNext()) {

            Node node = iter.next();

            if (name.equals(node.getNodeName())) {

                return node;

            }

        }

        return null;

    }

    public Node item(int index) {

        Node node = nodes.get(index);

        return node;

    }

    public Node removeNamedItem(java.lang.String name) {

        throw new DOMException(DOMException.NO_MODIFICATION_ALLOWED_ERR,

                               "This NamedNodeMap is read-only!");

    }

    public Node setNamedItem(Node arg) {

        throw new DOMException(DOMException.NO_MODIFICATION_ALLOWED_ERR,

                               "This NamedNodeMap is read-only!");

    }

    /**

     * Equivalent to {@code getNamedItem(localName)}.

     */

    public Node getNamedItemNS(String namespaceURI, String localName) {

        return getNamedItem(localName);

    }

    /**

     * Equivalent to {@code setNamedItem(arg)}.

     */

    public Node setNamedItemNS(Node arg) {

        return setNamedItem(arg);

    }

    /**

     * Equivalent to {@code removeNamedItem(localName)}.

     */

    public Node removeNamedItemNS(String namespaceURI, String localName) {

        return removeNamedItem(localName);

    }

}

class IIONodeList implements NodeList {

    List<? extends Node> nodes;

    public IIONodeList(List<? extends Node> nodes) {

        this.nodes = nodes;

    }

    public int getLength() {

        return nodes.size();

    }

    public Node item(int index) {

        if (index < 0 || index >= nodes.size()) {

            return null;

        }

        return nodes.get(index);

    }

}

class IIOAttr extends IIOMetadataNode implements Attr {

    Element owner;

    String name;

    String value;

    public IIOAttr(Element owner, String name, String value) {

        this.owner = owner;

        this.name = name;

        this.value = value;

    }

    public String getName() {

        return name;

    }

    public String getNodeName() {

        return name;

    }

    public short getNodeType() {

        return ATTRIBUTE_NODE;

    }

    public boolean getSpecified() {

        return true;

    }

    public String getValue() {

        return value;

    }

    public String getNodeValue() {

        return value;

    }

    public void setValue(String value) {

        this.value = value;

    }

    public void setNodeValue(String value) {

        this.value = value;

    }

    public Element getOwnerElement() {

        return owner;

    }

    public void setOwnerElement(Element owner) {

        this.owner = owner;

    }

    /** This method is new in the DOM L3 for Attr interface.

     * Could throw DOMException here, but its probably OK

     * to always return false. One reason for this, is we have no good

     * way to document this exception, since this class, IIOAttr,

     * is not a public class. The rest of the methods that throw

     * DOMException are publically documented as such on IIOMetadataNode.

     * @return false

     */

    public boolean isId() {

        return false;

    }

}

/**

 * A class representing a node in a meta-data tree, which implements

 * for the storage of non-textual objects via the

 * {@code getUserObject} and {@code setUserObject} methods.

 *

 * <p> This class is not intended to be used for general XML

 * processing. In particular, {@code Element} nodes created

 * within the Image I/O API are not compatible with those created by

 * Sun's standard implementation of the {@code org.w3.dom} API.

 * In particular, the implementation is tuned for simple uses and may

 * not perform well for intensive processing.

 *

 * <p> Namespaces are ignored in this implementation.  The terms "tag

 * name" and "node name" are always considered to be synonymous.

 *

 * <em>Note:</em>

 * The DOM Level 3 specification added a number of new methods to the

 * {@code Node}, {@code Element} and {@code Attr} interfaces that are not

 * of value to the {@code IIOMetadataNode} implementation or specification.

 *

 * Calling such methods on an {@code IIOMetadataNode}, or an {@code Attr}

 * instance returned from an {@code IIOMetadataNode} will result in a

 * {@code DOMException} being thrown.

 *

 * @see IIOMetadata#getAsTree

 * @see IIOMetadata#setFromTree

 * @see IIOMetadata#mergeTree

 *

 */

public class IIOMetadataNode implements Element, NodeList {

    /**

     * The name of the node as a {@code String}.

     */

    private String nodeName = null;

    /**

     * The value of the node as a {@code String}.  The Image I/O

     * API typically does not make use of the node value.

     */

    private String nodeValue = null;

    /**

     * The {@code Object} value associated with this node.

     */

    private Object userObject = null;

    /**

     * The parent node of this node, or {@code null} if this node

     * forms the root of its own tree.

     */

    private IIOMetadataNode parent = null;

    /**

     * The number of child nodes.

     */

    private int numChildren = 0;

    /**

     * The first (leftmost) child node of this node, or

     * {@code null} if this node is a leaf node.

     */

    private IIOMetadataNode firstChild = null;

    /**

     * The last (rightmost) child node of this node, or

     * {@code null} if this node is a leaf node.

     */

    private IIOMetadataNode lastChild = null;

    /**

     * The next (right) sibling node of this node, or

     * {@code null} if this node is its parent's last child node.

     */

    private IIOMetadataNode nextSibling = null;

    /**

     * The previous (left) sibling node of this node, or

     * {@code null} if this node is its parent's first child node.

     */

    private IIOMetadataNode previousSibling = null;

    /**

     * A {@code List} of {@code IIOAttr} nodes representing

     * attributes.

     */

    private List<IIOAttr> attributes = new ArrayList<>();

    /**

     * Constructs an empty {@code IIOMetadataNode}.

     */

    public IIOMetadataNode() {}

    /**

     * Constructs an {@code IIOMetadataNode} with a given node

     * name.

     *

     * @param nodeName the name of the node, as a {@code String}.

     */

    public IIOMetadataNode(String nodeName) {

        this.nodeName = nodeName;

    }

    /**

     * Check that the node is either {@code null} or an

     * {@code IIOMetadataNode}.

     *

     * @throws DOMException if {@code node} is not {@code null} and not an

     * instance of {@code IIOMetadataNode}

     */

    private void checkNode(Node node) throws DOMException {

        if (node == null) {

            return;

        }

        if (!(node instanceof IIOMetadataNode)) {

            throw new IIODOMException(DOMException.WRONG_DOCUMENT_ERR,

                                      "Node not an IIOMetadataNode!");

        }

    }

    // Methods from Node

    /**

     * Returns the node name associated with this node.

     *

     * @return the node name, as a {@code String}.

     */

    public String getNodeName() {

        return nodeName;

    }

    /**

     * Returns the value associated with this node.

     *

     * @return the node value, as a {@code String}.

     */

    public String getNodeValue(){

        return nodeValue;

    }

    /**

     * Sets the {@code String} value associated with this node.

     */

    public void setNodeValue(String nodeValue) {

        this.nodeValue = nodeValue;

    }

    /**

     * Returns the node type, which is always

     * {@code ELEMENT_NODE}.

     *

     * @return the {@code short} value {@code ELEMENT_NODE}.

     */

    public short getNodeType() {

        return ELEMENT_NODE;

    }

    /**

     * Returns the parent of this node.  A {@code null} value

     * indicates that the node is the root of its own tree.  To add a

     * node to an existing tree, use one of the

     * {@code insertBefore}, {@code replaceChild}, or

     * {@code appendChild} methods.

     *

     * @return the parent, as a {@code Node}.

     *

     * @see #insertBefore

     * @see #replaceChild

     * @see #appendChild

     */

    public Node getParentNode() {

        return parent;

    }

    /**

     * Returns a {@code NodeList} that contains all children of this node.

     * If there are no children, this is a {@code NodeList} containing

     * no nodes.

     *

     * @return the children as a {@code NodeList}

     */

    public NodeList getChildNodes() {

        return this;

    }

    /**

     * Returns the first child of this node, or {@code null} if

     * the node has no children.

     *

     * @return the first child, as a {@code Node}, or

     * {@code null}

     */

    public Node getFirstChild() {

        return firstChild;

    }

    /**

     * Returns the last child of this node, or {@code null} if

     * the node has no children.

     *

     * @return the last child, as a {@code Node}, or

     * {@code null}.

     */

    public Node getLastChild() {

        return lastChild;

    }

    /**

     * Returns the previous sibling of this node, or {@code null}

     * if this node has no previous sibling.

     *

     * @return the previous sibling, as a {@code Node}, or

     * {@code null}.

     */

    public Node getPreviousSibling() {

        return previousSibling;

    }

    /**

     * Returns the next sibling of this node, or {@code null} if

     * the node has no next sibling.

     *

     * @return the next sibling, as a {@code Node}, or

     * {@code null}.

     */

    public Node getNextSibling() {

        return nextSibling;

    }

    /**

     * Returns a {@code NamedNodeMap} containing the attributes of

     * this node.

     *

     * @return a {@code NamedNodeMap} containing the attributes of

     * this node.

     */

    public NamedNodeMap getAttributes() {

        return new IIONamedNodeMap(attributes);

    }

    /**

     * Returns {@code null}, since {@code IIOMetadataNode}s

     * do not belong to any {@code Document}.

     *

     * @return {@code null}.

     */

    public Document getOwnerDocument() {

        return null;

    }

    /**

     * Inserts the node {@code newChild} before the existing

     * child node {@code refChild}. If {@code refChild} is

     * {@code null}, insert {@code newChild} at the end of

     * the list of children.

     *

     * @param newChild the {@code Node} to insert.

     * @param refChild the reference {@code Node}.

     *

     * @return the node being inserted.

     *

     * @exception IllegalArgumentException if {@code newChild} is

     * {@code null}.

     */

    public Node insertBefore(Node newChild,

                             Node refChild) {

        if (newChild == null) {

            throw new IllegalArgumentException("newChild == null!");

        }

        checkNode(newChild);

        checkNode(refChild);

        IIOMetadataNode newChildNode = (IIOMetadataNode)newChild;

        IIOMetadataNode refChildNode = (IIOMetadataNode)refChild;

        // Siblings, can be null.

        IIOMetadataNode previous = null;

        IIOMetadataNode next = null;

        if (refChild == null) {

            previous = this.lastChild;

            next = null;

            this.lastChild = newChildNode;

        } else {

            previous = refChildNode.previousSibling;

            next = refChildNode;

        }

        if (previous != null) {

            previous.nextSibling = newChildNode;

        }

        if (next != null) {

            next.previousSibling = newChildNode;

        }

        newChildNode.parent = this;

        newChildNode.previousSibling = previous;

        newChildNode.nextSibling = next;

        // N.B.: O.K. if refChild == null

        if (this.firstChild == refChildNode) {

            this.firstChild = newChildNode;

        }

        ++numChildren;

        return newChildNode;

    }

    /**

     * Replaces the child node {@code oldChild} with

     * {@code newChild} in the list of children, and returns the

     * {@code oldChild} node.

     *

     * @param newChild the {@code Node} to insert.

     * @param oldChild the {@code Node} to be replaced.