/*
 * Copyright 2007 Sun Microsystems, Inc.  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.  Sun designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 */

package com.sun.media.sound;

import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.util.HashMap;
import java.util.Map;

import javax.sound.sampled.AudioFileFormat;
import javax.sound.sampled.AudioFormat;
import javax.sound.sampled.AudioInputStream;
import javax.sound.sampled.AudioSystem;
import javax.sound.sampled.UnsupportedAudioFileException;
import javax.sound.sampled.AudioFormat.Encoding;
import javax.sound.sampled.spi.AudioFileReader;

/**
 * WAVE file reader for files using format WAVE_FORMAT_EXTENSIBLE (0xFFFE).
 * 
 * @version %I%, %E%
 * @author Karl Helgason
 */

public class WaveExtensibleFileReader extends AudioFileReader {

	
	static private class GUID
	{
		long i1;
		int s1;
		int s2;
		int x1;
		int x2;
		int x3;
		int x4;
		int x5;
		int x6;
		int x7;
		int x8;
		
		private GUID()
		{			
		}
		public GUID(long i1, int s1, int s2, int x1, int x2, int x3, int x4, int x5, int x6, int x7, int x8)
		{
			this.i1 = i1;
			this.s1 = s1;
			this.s2 = s2;
			this.x1 = x1;
			this.x2 = x2;
			this.x3 = x3;
			this.x4 = x4;
			this.x5 = x5;
			this.x6 = x6;
			this.x7 = x7;
			this.x8 = x8;
		}
		
		public static GUID read(RIFFReader riff) throws IOException
		{
			GUID d = new GUID();
			d.i1 = riff.readUnsignedInt();
			d.s1 = riff.readUnsignedShort();
			d.s2 = riff.readUnsignedShort();
			d.x1 = riff.readUnsignedByte();
			d.x2 = riff.readUnsignedByte();
			d.x3 = riff.readUnsignedByte();
			d.x4 = riff.readUnsignedByte();
			d.x5 = riff.readUnsignedByte();
			d.x6 = riff.readUnsignedByte();
			d.x7 = riff.readUnsignedByte();
			d.x8 = riff.readUnsignedByte();
			return d;
		}
		
		public boolean equals(Object obj) {
			if(!(obj instanceof GUID)) return false;
			GUID t = (GUID)obj;
			if(i1 != t.i1) return false;
			if(s1 != t.s1) return false;
			if(s2 != t.s2) return false;
			if(x1 != t.x1) return false;
			if(x2 != t.x2) return false;
			if(x3 != t.x3) return false;
			if(x4 != t.x4) return false;
			if(x5 != t.x5) return false;
			if(x6 != t.x6) return false;
			if(x7 != t.x7) return false;
			if(x8 != t.x8) return false;
			return true;
		}
		
		
	}
	
	private static String[] channelnames = 
	   { "FL", "FR", "FC", "LF", "BL", "BR", // 5.1 
		 "FLC", "FLR", "BC", "SL", "SR",
		 "TC", "TFL", "TFC", "TFR", "TBL", "TBC", "TBR"};	
	
	private static String[] allchannelnames = 
	   { "w1",  "w2",  "w3",  "w4",  "w5",  "w6",  "w7",  "w8",  "w9", "w10",
		"w11", "w12", "w13", "w14", "w15", "w16", "w17", "w18", "w19", "w20",
		"w21", "w22", "w23", "w24", "w25", "w26", "w27", "w28", "w29", "w30",
		"w31", "w32", "w33", "w34", "w35", "w36", "w37", "w38", "w39", "w40",
		"w41", "w42", "w43", "w44", "w45", "w46", "w47", "w48", "w49", "w50",
		"w51", "w52", "w53", "w54", "w55", "w56", "w57", "w58", "w59", "w60",
		"w61", "w62", "w63", "w64"};
	
	private static GUID SUBTYPE_PCM        =  new GUID(0x00000001,0x0000,0x0010,0x80,0x00,0x00,0xaa,0x00,0x38,0x9b,0x71);
	private static GUID SUBTYPE_IEEE_FLOAT =  new GUID(0x00000003,0x0000,0x0010,0x80,0x00,0x00,0xaa,0x00,0x38,0x9b,0x71);

	private String decodeChannelMask(long channelmask)
	{
		StringBuffer sb = new StringBuffer();
		long m = 1;
		for (int i = 0; i < allchannelnames.length; i++) {
			if((channelmask & m) != 0L)
			{
				if(i < channelnames.length)
				{
					sb.append(channelnames[i] + " ");
				}
				else
				{
					sb.append(allchannelnames[i] + " ");				
				}	
			}
			m *= 2L;
		}
		if(sb.length() == 0) return null;
		return sb.substring(0, sb.length() - 1);
		
	}

	public AudioFileFormat getAudioFileFormat(InputStream stream)
			throws UnsupportedAudioFileException, IOException {

		stream.mark(200);
		AudioFileFormat format;
		try {
			format = internal_getAudioFileFormat(stream);
		} finally {
			stream.reset();
		}
		return format;
	}

	private AudioFileFormat internal_getAudioFileFormat(InputStream stream)
			throws UnsupportedAudioFileException, IOException {

		RIFFReader riffiterator = new RIFFReader(stream);
		if (!riffiterator.getFormat().equals("RIFF"))
			throw new UnsupportedAudioFileException();
		if (!riffiterator.getType().equals("WAVE"))
			throw new UnsupportedAudioFileException();

		boolean fmt_found = false;
		boolean data_found = false;

		int channels = 1;
		long samplerate = 1;
		//long framerate = 1;
		int framesize = 1;
		int bits = 1;
		int validBitsPerSample = 1;
		long channelMask = 0;
		GUID subFormat = null;

		while (riffiterator.hasNextChunk()) {
			RIFFReader chunk = riffiterator.nextChunk();

			if (chunk.getFormat().equals("fmt ")) {
				fmt_found = true;

				int format = chunk.readUnsignedShort();
				if (format != 0xFFFE)
					throw new UnsupportedAudioFileException(); // WAVE_FORMAT_EXTENSIBLE
																// only
				channels = chunk.readUnsignedShort();
				samplerate = chunk.readUnsignedInt();
				/*framerate =*/ chunk.readUnsignedInt();
				framesize = chunk.readUnsignedShort();
				bits = chunk.readUnsignedShort();
				int cbSize = chunk.readUnsignedShort();
				if (cbSize != 22)
					throw new UnsupportedAudioFileException();				
				validBitsPerSample = chunk.readUnsignedShort();
				if(validBitsPerSample > bits)
					throw new UnsupportedAudioFileException();
				channelMask = chunk.readUnsignedInt();
				subFormat = GUID.read(chunk);

			}
			if (chunk.getFormat().equals("data")) {
				data_found = true;
				break;
			}
		}

		if (!fmt_found)
			throw new UnsupportedAudioFileException();
		if (!data_found)
			throw new UnsupportedAudioFileException();

		Map<String, Object> p = new HashMap<String, Object>();
		String s_channelmask = decodeChannelMask(channelMask);
		if(s_channelmask != null)
			p.put("channelOrder", s_channelmask);
		if(channelMask != 0)
			p.put("channelMask", channelMask);
		// validBitsPerSample is only informational for PCM data,
		// data is still encode according to SampleSizeInBits.
		p.put("validBitsPerSample", validBitsPerSample);
		
		AudioFormat audioformat = null;
		if(subFormat.equals(SUBTYPE_PCM))
		{
			if(bits == 8)
			{
				audioformat = new AudioFormat(
						Encoding.PCM_UNSIGNED, samplerate, bits, channels,
						framesize, samplerate, false, p );
			}
			else
			{
				audioformat = new AudioFormat(
						Encoding.PCM_SIGNED, samplerate, bits, channels,
						framesize, samplerate, false, p );
			}
		}
		else
		if(subFormat.equals(SUBTYPE_IEEE_FLOAT))
		{
			audioformat = new AudioFormat(
					AudioFloatConverter.PCM_FLOAT, samplerate, bits, channels,
					framesize, samplerate, false, p );			
		}
		else
			throw new UnsupportedAudioFileException();
		

		AudioFileFormat fileformat = new AudioFileFormat(
				AudioFileFormat.Type.WAVE, audioformat,
				AudioSystem.NOT_SPECIFIED);
		return fileformat;
	}

	public AudioInputStream getAudioInputStream(InputStream stream)
			throws UnsupportedAudioFileException, IOException {

		AudioFileFormat format = getAudioFileFormat(stream);
		RIFFReader riffiterator = new RIFFReader(stream);
		if (!riffiterator.getFormat().equals("RIFF"))
			throw new UnsupportedAudioFileException();
		if (!riffiterator.getType().equals("WAVE"))
			throw new UnsupportedAudioFileException();
		while (riffiterator.hasNextChunk()) {
			RIFFReader chunk = riffiterator.nextChunk();
			if (chunk.getFormat().equals("data")) {
				return new AudioInputStream(chunk, format.getFormat(), chunk
						.getSize());
			}
		}
		throw new UnsupportedAudioFileException();
	}

	public AudioFileFormat getAudioFileFormat(URL url)
			throws UnsupportedAudioFileException, IOException {
		InputStream stream = url.openStream();
		AudioFileFormat format;
		try {
			format = getAudioFileFormat(new BufferedInputStream(stream));
		} finally {
			stream.close();
		}
		return format;
	}

	public AudioFileFormat getAudioFileFormat(File file)
			throws UnsupportedAudioFileException, IOException {
		InputStream stream = new FileInputStream(file);
		AudioFileFormat format;
		try {
			format = getAudioFileFormat(new BufferedInputStream(stream));
		} finally {
			stream.close();
		}
		return format;
	}

	public AudioInputStream getAudioInputStream(URL url)
			throws UnsupportedAudioFileException, IOException {
		return getAudioInputStream(new BufferedInputStream(url.openStream()));
	}

	public AudioInputStream getAudioInputStream(File file)
			throws UnsupportedAudioFileException, IOException {
		return getAudioInputStream(new BufferedInputStream(new FileInputStream(
				file)));
	}

}