/*
 * The Relaxer artifact
 * Copyright (c) 2000-2004, ASAMI Tomoharu, All rights reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer. 
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
package galatea.relaxer.event;

import java.util.*;
import org.w3c.dom.*;

/**
 * RStack
 *
 * @since   Mar.  8, 2000
 * @version May. 22, 2003
 * @author  ASAMI, Tomoharu (asami@relaxer.org)
 */
public final class RStack {
    private Element element_;
    private Object[] children_;
    // Set<String>
//    private HashSet consumedAttrs_ = new HashSet();
    // Set<Attr>
    private HashSet consumedAttrNodes_ = null;
    // Set<Element>
    private HashSet consumedElementNodes_ = null;
    // Map<String, String>
    private HashMap pi_ = new HashMap();
    private int index_;
//    private Element lastPoppedElemnt_ = null;

    protected RStack() {
    }

    public RStack(Element element) {
	element_ = element;
	NodeList nodes = element.getChildNodes();
	List list = new ArrayList();
	_makeList(nodes, list);
	int size = list.size();
	children_ = new Object[size];
	children_ = list.toArray(children_);
	index_ = 0;
    }

    private void _makeList(NodeList nodes, List list) {
	int size = nodes.getLength();
	StringBuffer buffer = null;
	for (int i = 0;i < size;i++) {
	    Node node = nodes.item(i);
	    if (node instanceof Element) {
		if (buffer != null) {
		    list.add(new String(buffer));
		    buffer = null;
		}
		list.add(node);
	    } else if (node instanceof Text) {
		if (buffer == null) {
		    buffer = new StringBuffer();
		}
		buffer.append(((Text)node).getData());
	    } else if (node instanceof ProcessingInstruction) {
		ProcessingInstruction pi = (ProcessingInstruction)node;
		pi_.put(pi.getTarget(), pi.getData());
	    } else if (node instanceof EntityReference) {
		_makeList(node.getChildNodes(), list);
	    }
	}
	if (buffer != null) {
	    list.add(new String(buffer));
	}
    }

    public Element getContextElement() {
	return (element_);
    }

/*
    public Element getLastPoppedElement() {
	return (lastPoppedElemnt_);
    }
*/

    public boolean isEmpty() {
	return (index_ == children_.length);
    }

    public boolean isEmptyElement() {
	if (index_ == children_.length) {
	    return (true);
	}
	for (int i = index_;i < children_.length;i++) {
	    if (children_[i] instanceof Element) {
		return (false);
	    }
	}
	return (true);
    }

    public Object pop() {
	return (children_[index_++]);
    }

    public Object peek() {
	if (index_ == children_.length) {
	    return (null);
	}
	return (children_[index_]);
    }

    public Element popElement() {
	if (index_ == children_.length) {
	    return (null);
	}
	while (index_ < children_.length) {
	    Object node = children_[index_++];
	    if (node instanceof Element) {
//		lastPoppedElemnt_ = (Element)node;
//		return (lastPoppedElemnt_);
		return ((Element)node);
	    }
	}
	return (null);
    }

    public Element peekElement() {
	if (index_ == children_.length) {
	    return (null);
	}
	for (int i = index_;i < children_.length;i++) {
	    Object node = children_[i];
	    if (node instanceof Element) {
		return ((Element)node);
	    }
	}
	return (null);
    }

    public Element[] peekElements() {
	if (index_ == children_.length) {
	    return (null);
	}
	List list = new ArrayList();
	for (int i = index_;i < children_.length;i++) {
	    Object node = children_[i];
	    if (node instanceof Element) {
		list.add(node);
	    }
	}
	Element[] elements = new Element[list.size()];
	return ((Element[])list.toArray(elements));
    }

/*
    public boolean hasAttributeHungry(String name) {
	if (isConsumedAttribute(name)) {
	    return (false);
	}
	setCosumedAttribute(name);
	return (URelaxer.hasAttribute(element_, name));
    }
*/

/*
    public boolean isConsumedAttribute(String name) {
	return (consumedAttrs_.contains(name));
    }

    public boolean isConsumedAttribute(String uri, String name) {
	return (consumedAttrs_.contains(uri + "$" + name));
    }

    public void setConsumedAttribute(String name) {
	if (isConsumedAttribute(name)) {
	    throw (new InternalError());
	}
	consumedAttrs_.add(name);
    }

    public void setConsumedAttribute(String uri, String name) {
	String fullname = uri + "$" + name;
	if (isConsumedAttribute(fullname)) {
	    throw (new InternalError());
	}
	consumedAttrs_.add(fullname);
    }
*/

    public Map getPIMap() {
	return ((Map)pi_.clone());
    }

    public boolean isConsumedElement(Attr attr) {
	if (consumedElementNodes_ == null) {
	    return (false);
	}
	return (consumedElementNodes_.contains(attr));
    }

    public void consumeElement(Attr attr) {
	if (consumedElementNodes_ == null) {
	    consumedElementNodes_ = new HashSet();
	}
	consumedElementNodes_.add(attr);
    }

    public boolean isConsumedAttribute(Attr attr) {
	if (consumedAttrNodes_ == null) {
	    return (false);
	}
	return (consumedAttrNodes_.contains(attr));
    }

    public void consumeAttribute(Attr attr) {
	if (attr == null) {
	    return;
	}
	if (consumedAttrNodes_ == null) {
	    consumedAttrNodes_ = new HashSet();
	}
	consumedAttrNodes_.add(attr);
    }

    public void addDirectAttributes(Map map) {
	NamedNodeMap attrs = element_.getAttributes();
	int size = attrs.getLength();
	for (int i = 0;i < size;i++) {
	    Attr attr = (Attr)attrs.item(i);
	    if (!isConsumedAttribute(attr)) {
		map.put(attr.getName(), attr.getValue());
	    }
	}
    }

    public RStack makeClone() {
	RStack newStack = new RStack();
	newStack.element_ = element_;
	newStack.children_ = (Object[])children_.clone();
	if (consumedAttrNodes_ != null) {
	    newStack.consumedAttrNodes_
		= (HashSet)consumedAttrNodes_.clone();
	}
	if (consumedElementNodes_ != null) {
	    newStack.consumedElementNodes_
		= (HashSet)consumedElementNodes_.clone();
	}
	newStack.pi_ = (HashMap)pi_.clone();
	newStack.index_ = index_;
	return (newStack);
    }

    public String toString() {
	StringBuffer buffer = new StringBuffer();
	buffer.append("[");
	if (index_ < children_.length) {
	    Object object = children_[index_];
	    buffer.append(object);
	    for (int i = index_ + 1;i < children_.length;i++) {
		buffer.append(",");
		object = children_[i];
		buffer.append(object);
	    }
	}
	buffer.append("]");
	return (new String(buffer));
    }
}
