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	/*
	* Copyright (c) 2001, 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 com.sun.imageio.plugins.jpeg;

	import javax.imageio.metadata.IIOInvalidTreeException;
	import javax.imageio.metadata.IIOMetadataNode;
	import javax.imageio.stream.ImageOutputStream;
	import javax.imageio.plugins.jpeg.JPEGHuffmanTable;

	import java.io.IOException;
	import java.util.List;
	import java.util.ArrayList;
	import java.util.Iterator;

	import org.w3c.dom.Node;
	import org.w3c.dom.NodeList;
	import org.w3c.dom.NamedNodeMap;

	/**
	* A DHT (Define Huffman Table) marker segment.
	*/
	class DHTMarkerSegment extends MarkerSegment {
	List tables = new ArrayList();

	DHTMarkerSegment(boolean needFour) {
	super(JPEG.DHT);
	tables.add(new Htable(JPEGHuffmanTable.StdDCLuminance, true, 0));
	if (needFour) {
	tables.add(new Htable(JPEGHuffmanTable.StdDCChrominance, true, 1));
	}
	tables.add(new Htable(JPEGHuffmanTable.StdACLuminance, false, 0));
	if (needFour) {
	tables.add(new Htable(JPEGHuffmanTable.StdACChrominance, false, 1));
	}
	}

	DHTMarkerSegment(JPEGBuffer buffer) throws IOException {
	super(buffer);
	int count = length;
	while (count > 0) {
	Htable newGuy = new Htable(buffer);
	tables.add(newGuy);
	count -= 1 + 16 + newGuy.values.length;
	}
	buffer.bufAvail -= length;
	}

	DHTMarkerSegment(JPEGHuffmanTable[] dcTables,
	JPEGHuffmanTable[] acTables) {
	super(JPEG.DHT);
	for (int i = 0; i < dcTables.length; i++) {
	tables.add(new Htable(dcTables[i], true, i));
	}
	for (int i = 0; i < acTables.length; i++) {
	tables.add(new Htable(acTables[i], false, i));
	}
	}

	DHTMarkerSegment(Node node) throws IIOInvalidTreeException {
	super(JPEG.DHT);
	NodeList children = node.getChildNodes();
	int size = children.getLength();
	if ((size < 1) \|\| (size > 4)) {
	throw new IIOInvalidTreeException("Invalid DHT node", node);
	}
	for (int i = 0; i < size; i++) {
	tables.add(new Htable(children.item(i)));
	}
	}

	protected Object clone() {
	DHTMarkerSegment newGuy = (DHTMarkerSegment) super.clone();
	newGuy.tables = new ArrayList(tables.size());
	Iterator iter = tables.iterator();
	while (iter.hasNext()) {
	Htable table = (Htable) iter.next();
	newGuy.tables.add(table.clone());
	}
	return newGuy;
	}

	IIOMetadataNode getNativeNode() {
	IIOMetadataNode node = new IIOMetadataNode("dht");
	for (int i= 0; i<tables.size(); i++) {
	Htable table = (Htable) tables.get(i);
	node.appendChild(table.getNativeNode());
	}
	return node;
	}

	/**
	* Writes the data for this segment to the stream in
	* valid JPEG format.
	*/
	void write(ImageOutputStream ios) throws IOException {
	// We don't write DHT segments; the IJG library does.
	}

	void print() {
	printTag("DHT");
	System.out.println("Num tables: "
	+ Integer.toString(tables.size()));
	for (int i= 0; i<tables.size(); i++) {
	Htable table = (Htable) tables.get(i);
	table.print();
	}
	System.out.println();

	}

	Htable getHtableFromNode(Node node) throws IIOInvalidTreeException {
	return new Htable(node);
	}

	void addHtable(JPEGHuffmanTable table, boolean isDC, int id) {
	tables.add(new Htable(table, isDC, id));
	}

	/**
	* A Huffman table within a DHT marker segment.
	*/
	class Htable implements Cloneable {
	int tableClass; // 0 == DC, 1 == AC
	int tableID; // 0 - 4
	private static final int NUM_LENGTHS = 16;
	// # of codes of each length
	short [] numCodes = new short[NUM_LENGTHS];
	short [] values;

	Htable(JPEGBuffer buffer) {
	tableClass = buffer.buf[buffer.bufPtr] >>> 4;
	tableID = buffer.buf[buffer.bufPtr++] & 0xf;
	for (int i = 0; i < NUM_LENGTHS; i++) {
	numCodes[i] = (short) (buffer.buf[buffer.bufPtr++] & 0xff);
	}

	int numValues = 0;
	for (int i = 0; i < NUM_LENGTHS; i++) {
	numValues += numCodes[i];
	}
	values = new short[numValues];
	for (int i = 0; i < numValues; i++) {
	values[i] = (short) (buffer.buf[buffer.bufPtr++] & 0xff);
	}
	}

	Htable(JPEGHuffmanTable table, boolean isDC, int id) {
	tableClass = isDC ? 0 : 1;
	tableID = id;
	numCodes = table.getLengths();
	values = table.getValues();
	}

	Htable(Node node) throws IIOInvalidTreeException {
	if (node.getNodeName().equals("dhtable")) {
	NamedNodeMap attrs = node.getAttributes();
	int count = attrs.getLength();
	if (count != 2) {
	throw new IIOInvalidTreeException
	("dhtable node must have 2 attributes", node);
	}
	tableClass = getAttributeValue(node, attrs, "class", 0, 1, true);
	tableID = getAttributeValue(node, attrs, "htableId", 0, 3, true);
	if (node instanceof IIOMetadataNode) {
	IIOMetadataNode ourNode = (IIOMetadataNode) node;
	JPEGHuffmanTable table =
	(JPEGHuffmanTable) ourNode.getUserObject();
	if (table == null) {
	throw new IIOInvalidTreeException
	("dhtable node must have user object", node);
	}
	numCodes = table.getLengths();
	values = table.getValues();
	} else {
	throw new IIOInvalidTreeException
	("dhtable node must have user object", node);
	}
	} else {
	throw new IIOInvalidTreeException
	("Invalid node, expected dqtable", node);
	}

	}

	protected Object clone() {
	Htable newGuy = null;
	try {
	newGuy = (Htable) super.clone();
	} catch (CloneNotSupportedException e) {} // won't happen
	if (numCodes != null) {
	newGuy.numCodes = (short []) numCodes.clone();
	}
	if (values != null) {
	newGuy.values = (short []) values.clone();
	}
	return newGuy;
	}

	IIOMetadataNode getNativeNode() {
	IIOMetadataNode node = new IIOMetadataNode("dhtable");
	node.setAttribute("class", Integer.toString(tableClass));
	node.setAttribute("htableId", Integer.toString(tableID));

	node.setUserObject(new JPEGHuffmanTable(numCodes, values));

	return node;
	}


	void print() {
	System.out.println("Huffman Table");
	System.out.println("table class: "
	+ ((tableClass == 0) ? "DC":"AC"));
	System.out.println("table id: " + Integer.toString(tableID));

	(new JPEGHuffmanTable(numCodes, values)).toString();
	/*
	System.out.print("Lengths:");
	for (int i=0; i<16; i++) {
	System.out.print(" " + Integer.toString(numCodes[i]));
	}
	int count = 0;
	if (values.length > 16) {
	System.out.println("\nFirst 16 Values:");
	count = 16;
	} else {
	System.out.println("\nValues:");
	count = values.length;
	}
	for (int i=0; i<count; i++) {
	System.out.println(Integer.toString(values[i]&0xff));
	}
	*/
	}
	}

	}

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