/*

 * Copyright (c) 1999, 2013, 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

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package com.sun.media.sound;

import java.io.BufferedInputStream;

import java.io.DataInputStream;

import java.io.File;

import java.io.FileInputStream;

import java.io.IOException;

import java.io.InputStream;

import java.net.URL;

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;

/**

 * AU file reader.

 *

 * @author Kara Kytle

 * @author Jan Borgersen

 * @author Florian Bomers

 */

public final class AuFileReader extends SunFileReader {

    // METHODS TO IMPLEMENT AudioFileReader

    /**

     * Obtains the audio file format of the input stream provided.  The stream must

     * point to valid audio file data.  In general, audio file providers may

     * need to read some data from the stream before determining whether they

     * support it.  These parsers must

     * be able to mark the stream, read enough data to determine whether they

     * support the stream, and, if not, reset the stream's read pointer to its original

     * position.  If the input stream does not support this, this method may fail

     * with an IOException.

     * @param stream the input stream from which file format information should be

     * extracted

     * @return an <code>AudioFileFormat</code> object describing the audio file format

     * @throws UnsupportedAudioFileException if the stream does not point to valid audio

     * file data recognized by the system

     * @throws IOException if an I/O exception occurs

     * @see InputStream#markSupported

     * @see InputStream#mark

     */

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

        AudioFormat format = null;

        AuFileFormat fileFormat = null;

        int maxReadLength = 28;

        boolean bigendian  = false;

        int magic          = -1;

        int headerSize     = -1;

        int dataSize       = -1;

        int encoding_local = -1;

        int sampleRate     = -1;

        int frameRate      = -1;

        int frameSize      = -1;

        int channels       = -1;

        final int sampleSizeInBits;

        int length = 0;

        int nread = 0;

        AudioFormat.Encoding encoding = null;

        DataInputStream dis = new DataInputStream( stream );

        dis.mark(maxReadLength);

        magic = dis.readInt();

        if (! (magic == AuFileFormat.AU_SUN_MAGIC) || (magic == AuFileFormat.AU_DEC_MAGIC) ||

            (magic == AuFileFormat.AU_SUN_INV_MAGIC) || (magic == AuFileFormat.AU_DEC_INV_MAGIC) ) {

            // not AU, reset the stream, place into exception, throw exception

            dis.reset();

            throw new UnsupportedAudioFileException("not an AU file");

        }

        if ((magic == AuFileFormat.AU_SUN_MAGIC) || (magic == AuFileFormat.AU_DEC_MAGIC)) {

            bigendian = true;        // otherwise little-endian

        }

        headerSize     = (bigendian==true ? dis.readInt() : rllong(dis) );  nread += 4;

        dataSize       = (bigendian==true ? dis.readInt() : rllong(dis) );  nread += 4;

        encoding_local = (bigendian==true ? dis.readInt() : rllong(dis) );  nread += 4;

        sampleRate     = (bigendian==true ? dis.readInt() : rllong(dis) );  nread += 4;

        channels       = (bigendian==true ? dis.readInt() : rllong(dis) );  nread += 4;

        if (channels <= 0) {

            dis.reset();

            throw new UnsupportedAudioFileException("Invalid number of channels");

        }

        frameRate = sampleRate;

        switch (encoding_local) {

        case AuFileFormat.AU_ULAW_8:

            encoding = AudioFormat.Encoding.ULAW;

            sampleSizeInBits = 8;

            break;

        case AuFileFormat.AU_ALAW_8:

            encoding = AudioFormat.Encoding.ALAW;

            sampleSizeInBits = 8;

            break;

        case AuFileFormat.AU_LINEAR_8:

            // $$jb: 04.29.99: 8bit linear is *signed*, not *unsigned*

            encoding = AudioFormat.Encoding.PCM_SIGNED;

            sampleSizeInBits = 8;

            break;

        case AuFileFormat.AU_LINEAR_16:

            encoding = AudioFormat.Encoding.PCM_SIGNED;

            sampleSizeInBits = 16;

            break;

        case AuFileFormat.AU_LINEAR_24:

            encoding = AudioFormat.Encoding.PCM_SIGNED;

            sampleSizeInBits = 24;

            break;

        case AuFileFormat.AU_LINEAR_32:

            encoding = AudioFormat.Encoding.PCM_SIGNED;

            sampleSizeInBits = 32;

            break;

            // $jb: 03.19.99: we don't support these ...

            /*          case AuFileFormat.AU_FLOAT:

                        encoding = new AudioFormat.FLOAT;

                        sampleSizeInBits = 32;

                        break;

                        case AuFileFormat.AU_DOUBLE:

                        encoding = new AudioFormat.DOUBLE;

                        sampleSizeInBits = 8;

                        break;

                        case AuFileFormat.AU_ADPCM_G721:

                        encoding = new AudioFormat.G721_ADPCM;

                        sampleSizeInBits = 16;

                        break;

                        case AuFileFormat.AU_ADPCM_G723_3:

                        encoding = new AudioFormat.G723_3;

                        sampleSize = 24;

                        SamplePerUnit = 8;

                        break;

                        case AuFileFormat.AU_ADPCM_G723_5:

                        encoding = new AudioFormat.G723_5;

                        sampleSize = 40;

                        SamplePerUnit = 8;

                        break;

            */

        default:

                // unsupported filetype, throw exception

                dis.reset();

                throw new UnsupportedAudioFileException("not a valid AU file");

        }

        frameSize = calculatePCMFrameSize(sampleSizeInBits, channels);

        //$$fb 2002-11-02: fix for 4629669: AU file reader: problems with empty files

        if( dataSize < 0 ) {

            length = AudioSystem.NOT_SPECIFIED;

        } else {

            //$$fb 2003-10-20: fix for 4940459: AudioInputStream.getFrameLength() returns 0 instead of NOT_SPECIFIED

            length = dataSize / frameSize;

        }

        format = new AudioFormat( encoding, (float)sampleRate, sampleSizeInBits,

                                  channels, frameSize, (float)frameRate, bigendian);

        fileFormat = new AuFileFormat( AudioFileFormat.Type.AU, dataSize+headerSize,

                                       format, length);

        dis.reset(); // Throws IOException

        return fileFormat;

    }

    /**

     * Obtains the audio file format of the URL provided.  The URL must

     * point to valid audio file data.

     * @param url the URL from which file format information should be

     * extracted

     * @return an <code>AudioFileFormat</code> object describing the audio file format

     * @throws UnsupportedAudioFileException if the URL does not point to valid audio

     * file data recognized by the system

     * @throws IOException if an I/O exception occurs

     */

    public AudioFileFormat getAudioFileFormat(URL url) throws UnsupportedAudioFileException, IOException {

        InputStream                             urlStream = null;

        BufferedInputStream             bis = null;

        AudioFileFormat                 fileFormat = null;

        AudioFormat                             format = null;

        urlStream = url.openStream();   // throws IOException

        try {

            bis = new BufferedInputStream( urlStream, bisBufferSize );

            fileFormat = getAudioFileFormat( bis );             // throws UnsupportedAudioFileException

        } finally {

            urlStream.close();

        }

        return fileFormat;

    }

    /**

     * Obtains the audio file format of the File provided.  The File must

     * point to valid audio file data.

     * @param file the File from which file format information should be

     * extracted

     * @return an <code>AudioFileFormat</code> object describing the audio file format

     * @throws UnsupportedAudioFileException if the File does not point to valid audio

     * file data recognized by the system

     * @throws IOException if an I/O exception occurs

     */

    public AudioFileFormat getAudioFileFormat(File file) throws UnsupportedAudioFileException, IOException {

        FileInputStream                 fis = null;

        BufferedInputStream             bis = null;

        AudioFileFormat                 fileFormat = null;

        AudioFormat                             format = null;

        fis = new FileInputStream( file );      // throws IOException

        // part of fix for 4325421

        try {

            bis = new BufferedInputStream( fis, bisBufferSize );

            fileFormat = getAudioFileFormat( bis );             // throws UnsupportedAudioFileException

        } finally {

            fis.close();

        }

        return fileFormat;

    }

    /**

     * Obtains an audio stream from the input stream provided.  The stream must

     * point to valid audio file data.  In general, audio file providers may

     * need to read some data from the stream before determining whether they

     * support it.  These parsers must

     * be able to mark the stream, read enough data to determine whether they

     * support the stream, and, if not, reset the stream's read pointer to its original

     * position.  If the input stream does not support this, this method may fail

     * with an IOException.

     * @param stream the input stream from which the <code>AudioInputStream</code> should be

     * constructed

     * @return an <code>AudioInputStream</code> object based on the audio file data contained

     * in the input stream.

     * @throws UnsupportedAudioFileException if the stream does not point to valid audio

     * file data recognized by the system

     * @throws IOException if an I/O exception occurs

     * @see InputStream#markSupported

     * @see InputStream#mark

     */

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

        DataInputStream dis = null;

        int headerSize;

        AudioFileFormat fileFormat = null;

        AudioFormat format = null;

        fileFormat = getAudioFileFormat( stream ); // throws UnsupportedAudioFileException, IOException

        // if we passed this call, we have an AU file.

        format = fileFormat.getFormat();

        dis = new DataInputStream(stream);

        // now seek past the header

        dis.readInt(); // magic

        headerSize     = (format.isBigEndian()==true ? dis.readInt() : rllong(dis) );

        dis.skipBytes( headerSize - 8 );

        // we've got everything, and the stream should be at the

        // beginning of the data chunk, so return an AudioInputStream.

        return new AudioInputStream(dis, format, fileFormat.getFrameLength());

    }

    /**

     * Obtains an audio stream from the URL provided.  The URL must

     * point to valid audio file data.

     * @param url the URL for which the <code>AudioInputStream</code> should be

     * constructed

     * @return an <code>AudioInputStream</code> object based on the audio file data pointed

     * to by the URL

     * @throws UnsupportedAudioFileException if the URL does not point to valid audio

     * file data recognized by the system

     * @throws IOException if an I/O exception occurs

     */

    public AudioInputStream getAudioInputStream(URL url) throws UnsupportedAudioFileException, IOException {

        InputStream                             urlStream = null;

        BufferedInputStream             bis = null;

        AudioFileFormat                 fileFormat = null;

        urlStream = url.openStream();   // throws IOException

        AudioInputStream result = null;

        try {

            bis = new BufferedInputStream( urlStream, bisBufferSize );

            result = getAudioInputStream( (InputStream)bis );

        } finally {

            if (result == null) {

                urlStream.close();

            }

        }

        return result;

    }

    /**

     * Obtains an audio stream from the File provided.  The File must

     * point to valid audio file data.

     * @param file the File for which the <code>AudioInputStream</code> should be

     * constructed

     * @return an <code>AudioInputStream</code> object based on the audio file data pointed

     * to by the File

     * @throws UnsupportedAudioFileException if the File does not point to valid audio

     * file data recognized by the system

     * @throws IOException if an I/O exception occurs

     */

    public AudioInputStream getAudioInputStream(File file) throws UnsupportedAudioFileException, IOException {

        FileInputStream                 fis = null;

        BufferedInputStream             bis = null;

        AudioFileFormat                 fileFormat = null;

        fis = new FileInputStream( file );      // throws IOException

        AudioInputStream result = null;

        // part of fix for 4325421

        try {

            bis = new BufferedInputStream( fis, bisBufferSize );

            result = getAudioInputStream( (InputStream)bis );

        } finally {

            if (result == null) {

                fis.close();

            }

        }

        return result;

    }

}