package com.ctc.wstx.dom;

import javax.xml.namespace.NamespaceContext;

import org.w3c.dom.Element;
import org.w3c.dom.Node;

import com.ctc.wstx.sw.OutputElementBase;
import com.ctc.wstx.util.BijectiveNsMap;

Context object that holds information about an open element
(one for which START_ELEMENT has been sent, but no END_ELEMENT)
/**
 * Context object that holds information about an open element
 * (one for which START_ELEMENT has been sent, but no END_ELEMENT)
 */
public final class DOMOutputElement
    extends OutputElementBase
{
    
Reference to the parent element, element enclosing this element.
Null for root element.
Non-final to allow temporary pooling
(on per-writer basis, to keep these short-lived).
/**
     * Reference to the parent element, element enclosing this element.
     * Null for root element.
     * Non-final to allow temporary pooling
     * (on per-writer basis, to keep these short-lived).
     */
    private DOMOutputElement mParent;

    
DOM node that is the root under which content is written, in case where there is no parent (mParent == null). If mParent is not null, this will be null. Value is of type Document, DocumentFragment or Element /**
     * DOM node that is the root under which content is written, in case
     * where there is no parent (mParent == null). If mParent is not null,
     * this will be null.
     * Value is of type
     * {@link Document}, {@link DocumentFragment} or {@link Element}
     */
    private final Node mRootNode;
    
    
Actual DOM element for which this element object acts as a proxy.
/**
     * Actual DOM element for which this element object acts as a proxy.
     */
    private Element mElement;

    private boolean mDefaultNsSet;

    
Constructor for the virtual root element
/**
     * Constructor for the virtual root element
     */
    private DOMOutputElement(Node rootNode)
    {
        super();
        mRootNode = rootNode;
        mParent = null;
        mElement = null;
        mNsMapping = null;
        mNsMapShared = false;
        mDefaultNsURI = "";
        mRootNsContext = null;
        mDefaultNsSet = false;
    }

    private DOMOutputElement(DOMOutputElement parent, Element element, BijectiveNsMap ns)
    {
        super(parent, ns);
        mRootNode = null;
        mParent = parent;
        mElement = element;
        mNsMapping = ns;
        mNsMapShared = (ns != null);
        mDefaultNsURI = parent.mDefaultNsURI;
        mRootNsContext = parent.mRootNsContext;
        mDefaultNsSet = false;
    }

    
Method called to reuse a pooled instance.
@returns
Chained pooled instance that should now be head of the
  reuse chain/**
     * Method called to reuse a pooled instance.
     *
     * @returns Chained pooled instance that should now be head of the
     *   reuse chain
     */
    private void relink(DOMOutputElement parent, Element element)
    {
        super.relink(parent);
        mParent = parent;
        mElement = element;
        parent.appendNode(element);
        mDefaultNsSet = false;
    }

    public static DOMOutputElement createRoot(Node rootNode)
    {
        return new DOMOutputElement(rootNode);
    }
    
    
Simplest factory method, which gets called when a 1-argument
element output method is called. It is, then, assumed to
use the default namespace.
Will both create the child element and attach it to parent element,
or lacking own owner document.
/**
     * Simplest factory method, which gets called when a 1-argument
     * element output method is called. It is, then, assumed to
     * use the default namespace.
     * Will both create the child element and attach it to parent element,
     * or lacking own owner document.
     */
    protected DOMOutputElement createAndAttachChild(Element element)
    {
        if (mRootNode != null) {
            mRootNode.appendChild(element);
        } else {
            mElement.appendChild(element);
        }
        return createChild(element);
    }

    protected DOMOutputElement createChild(Element element)
    {
        return new DOMOutputElement(this, element, mNsMapping);
    }

    
Returns:
New head of the recycle pool/**
     * @return New head of the recycle pool
     */
    protected DOMOutputElement reuseAsChild(DOMOutputElement parent, Element element)
    {
        DOMOutputElement poolHead = mParent;
        relink(parent, element);
        return poolHead;
    }

    
Method called to temporarily link this instance to a pool, to
allow reusing of instances with the same reader.
/**
     * Method called to temporarily link this instance to a pool, to
     * allow reusing of instances with the same reader.
     */
    protected void addToPool(DOMOutputElement poolHead)
    {
        mParent = poolHead;
    }
    
    /*
    ///////////////////////////////////////////////////////////////////////
    // Public API, accessors
    ///////////////////////////////////////////////////////////////////////
     */

    public DOMOutputElement getParent() {
        return mParent;
    }

    @Override
    public boolean isRoot() {
        // (Virtual) Root element has no parent...
        return (mParent == null);
    }
    
    
Returns:
String presentation of the fully-qualified name, in
  "prefix:localName" format (no URI). Useful for error and
  debugging messages./**
     * @return String presentation of the fully-qualified name, in
     *   "prefix:localName" format (no URI). Useful for error and
     *   debugging messages.
     */
    @Override
    public String getNameDesc() {
        if(mElement != null) {
            return mElement.getLocalName();
        }
        return "#error"; // unexpected case
    }
    
    /*
    ///////////////////////////////////////////////////////////////////////
    // Public API, mutators
    ///////////////////////////////////////////////////////////////////////
     */

    @Override
    public void setDefaultNsUri(String uri) {
        mDefaultNsURI = uri;
        mDefaultNsSet = true;
    }

    @Override
    protected void setRootNsContext(NamespaceContext ctxt)
    {
        mRootNsContext = ctxt;
        /* Let's also see if we have an active default ns mapping:
         * (provided it hasn't yet explicitly been set for this element)
         */
        if (!mDefaultNsSet) {
            String defURI = ctxt.getNamespaceURI("");
            if (defURI != null && defURI.length() > 0) {
                mDefaultNsURI = defURI;
            }
        }
    }

    /*
    ///////////////////////////////////////////////////////////////////////
    // Public API, DOM manipulation
    ///////////////////////////////////////////////////////////////////////
     */
    
    protected void appendNode(Node n)
    {
        if (mRootNode != null) {
            mRootNode.appendChild(n);
        } else {
            mElement.appendChild(n);
        }
    }

    protected void addAttribute(String pname, String value)
    {
        mElement.setAttribute(pname, value);
    }

    protected void addAttribute(String uri, String qname, String value)
    {
        mElement.setAttributeNS(uri, qname, value);
    }

    public void appendChild(Node n) {
        mElement.appendChild(n);
    }
}