/*

 * 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.DataInputStream;

import java.io.IOException;

import java.io.InputStream;

import javax.sound.sampled.AudioFileFormat;

import javax.sound.sampled.AudioFormat;

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 {

    @Override

    public AudioFileFormat getAudioFileFormatImpl(final InputStream stream)

            throws UnsupportedAudioFileException, IOException {

        final DataInputStream dis = new DataInputStream(stream);

        final int magic = dis.readInt();

        if (magic != AuFileFormat.AU_SUN_MAGIC) {

            // not AU, throw exception

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

        }

        final int headerSize = dis.readInt();

        final int dataSize = dis.readInt();

        final int sampleRate = dis.readInt();

        final int channels = dis.readInt();

        if (channels <= 0) {

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

        }

        final int sampleSizeInBits;

        final AudioFormat.Encoding encoding;

                        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;

            */

        }

        final int frameSize = calculatePCMFrameSize(sampleSizeInBits, channels);

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

        final int length;

        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;

        }

        // now seek past the header

        dis.skipBytes(headerSize - AuFileFormat.AU_HEADERSIZE);

        final AudioFormat format = new AudioFormat(encoding, sampleRate,

                                                   sampleSizeInBits, channels,

                                                   frameSize, sampleRate, true);

    }

}