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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.IIOException;
	import javax.imageio.metadata.IIOInvalidTreeException;
	import javax.imageio.metadata.IIOMetadataNode;
	import javax.imageio.stream.ImageOutputStream;

	import java.io.IOException;

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

	/**
	* An SOS (Start Of Scan) marker segment.
	*/
	class SOSMarkerSegment extends MarkerSegment {
	int startSpectralSelection;
	int endSpectralSelection;
	int approxHigh;
	int approxLow;
	ScanComponentSpec [] componentSpecs; // Array size is numScanComponents

	SOSMarkerSegment(boolean willSubsample,
	byte[] componentIDs,
	int numComponents) {
	super(JPEG.SOS);
	startSpectralSelection = 0;
	endSpectralSelection = 63;
	approxHigh = 0;
	approxLow = 0;
	componentSpecs = new ScanComponentSpec[numComponents];
	for (int i = 0; i < numComponents; i++) {
	int tableSel = 0;
	if (willSubsample) {
	if ((i == 1) \|\| (i == 2)) {
	tableSel = 1;
	}
	}
	componentSpecs[i] = new ScanComponentSpec(componentIDs[i],
	tableSel);
	}
	}

	SOSMarkerSegment(JPEGBuffer buffer) throws IOException {
	super(buffer);
	int numComponents = buffer.buf[buffer.bufPtr++];
	componentSpecs = new ScanComponentSpec[numComponents];
	for (int i = 0; i < numComponents; i++) {
	componentSpecs[i] = new ScanComponentSpec(buffer);
	}
	startSpectralSelection = buffer.buf[buffer.bufPtr++];
	endSpectralSelection = buffer.buf[buffer.bufPtr++];
	approxHigh = buffer.buf[buffer.bufPtr] >> 4;
	approxLow = buffer.buf[buffer.bufPtr++] &0xf;
	buffer.bufAvail -= length;
	}

	SOSMarkerSegment(Node node) throws IIOInvalidTreeException {
	super(JPEG.SOS);
	startSpectralSelection = 0;
	endSpectralSelection = 63;
	approxHigh = 0;
	approxLow = 0;
	updateFromNativeNode(node, true);
	}

	protected Object clone () {
	SOSMarkerSegment newGuy = (SOSMarkerSegment) super.clone();
	if (componentSpecs != null) {
	newGuy.componentSpecs =
	(ScanComponentSpec []) componentSpecs.clone();
	for (int i = 0; i < componentSpecs.length; i++) {
	newGuy.componentSpecs[i] =
	(ScanComponentSpec) componentSpecs[i].clone();
	}
	}
	return newGuy;
	}

	IIOMetadataNode getNativeNode() {
	IIOMetadataNode node = new IIOMetadataNode("sos");
	node.setAttribute("numScanComponents",
	Integer.toString(componentSpecs.length));
	node.setAttribute("startSpectralSelection",
	Integer.toString(startSpectralSelection));
	node.setAttribute("endSpectralSelection",
	Integer.toString(endSpectralSelection));
	node.setAttribute("approxHigh",
	Integer.toString(approxHigh));
	node.setAttribute("approxLow",
	Integer.toString(approxLow));
	for (int i = 0; i < componentSpecs.length; i++) {
	node.appendChild(componentSpecs[i].getNativeNode());
	}

	return node;
	}

	void updateFromNativeNode(Node node, boolean fromScratch)
	throws IIOInvalidTreeException {
	NamedNodeMap attrs = node.getAttributes();
	int numComponents = getAttributeValue(node, attrs, "numScanComponents",
	1, 4, true);
	int value = getAttributeValue(node, attrs, "startSpectralSelection",
	0, 63, false);
	startSpectralSelection = (value != -1) ? value : startSpectralSelection;
	value = getAttributeValue(node, attrs, "endSpectralSelection",
	0, 63, false);
	endSpectralSelection = (value != -1) ? value : endSpectralSelection;
	value = getAttributeValue(node, attrs, "approxHigh", 0, 15, false);
	approxHigh = (value != -1) ? value : approxHigh;
	value = getAttributeValue(node, attrs, "approxLow", 0, 15, false);
	approxLow = (value != -1) ? value : approxLow;

	// Now the children
	NodeList children = node.getChildNodes();
	if (children.getLength() != numComponents) {
	throw new IIOInvalidTreeException
	("numScanComponents must match the number of children", node);
	}
	componentSpecs = new ScanComponentSpec[numComponents];
	for (int i = 0; i < numComponents; i++) {
	componentSpecs[i] = new ScanComponentSpec(children.item(i));
	}
	}

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

	void print () {
	printTag("SOS");
	System.out.print("Start spectral selection: ");
	System.out.println(startSpectralSelection);
	System.out.print("End spectral selection: ");
	System.out.println(endSpectralSelection);
	System.out.print("Approx high: ");
	System.out.println(approxHigh);
	System.out.print("Approx low: ");
	System.out.println(approxLow);
	System.out.print("Num scan components: ");
	System.out.println(componentSpecs.length);
	for (int i = 0; i< componentSpecs.length; i++) {
	componentSpecs[i].print();
	}
	}

	ScanComponentSpec getScanComponentSpec(byte componentSel, int tableSel) {
	return new ScanComponentSpec(componentSel, tableSel);
	}

	/**
	* A scan component spec within an SOS marker segment.
	*/
	class ScanComponentSpec implements Cloneable {
	int componentSelector;
	int dcHuffTable;
	int acHuffTable;

	ScanComponentSpec(byte componentSel, int tableSel) {
	componentSelector = componentSel;
	dcHuffTable = tableSel;
	acHuffTable = tableSel;
	}

	ScanComponentSpec(JPEGBuffer buffer) {
	// Parent already loaded the buffer
	componentSelector = buffer.buf[buffer.bufPtr++];
	dcHuffTable = buffer.buf[buffer.bufPtr] >> 4;
	acHuffTable = buffer.buf[buffer.bufPtr++] & 0xf;
	}

	ScanComponentSpec(Node node) throws IIOInvalidTreeException {
	NamedNodeMap attrs = node.getAttributes();
	componentSelector = getAttributeValue(node, attrs, "componentSelector",
	0, 255, true);
	dcHuffTable = getAttributeValue(node, attrs, "dcHuffTable",
	0, 3, true);
	acHuffTable = getAttributeValue(node, attrs, "acHuffTable",
	0, 3, true);
	}

	protected Object clone() {
	try {
	return super.clone();
	} catch (CloneNotSupportedException e) {} // won't happen
	return null;
	}

	IIOMetadataNode getNativeNode() {
	IIOMetadataNode node = new IIOMetadataNode("scanComponentSpec");
	node.setAttribute("componentSelector",
	Integer.toString(componentSelector));
	node.setAttribute("dcHuffTable",
	Integer.toString(dcHuffTable));
	node.setAttribute("acHuffTable",
	Integer.toString(acHuffTable));
	return node;
	}

	void print () {
	System.out.print("Component Selector: ");
	System.out.println(componentSelector);
	System.out.print("DC huffman table: ");
	System.out.println(dcHuffTable);
	System.out.print("AC huffman table: ");
	System.out.println(acHuffTable);
	}
	}

	}

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