/*

  * Entagged Audio Tag library

  * Copyright (c) 2003-2005 Raphaël Slinckx <raphael@slinckx.net>

  * 

  * This library is free software; you can redistribute it and/or

  * modify it under the terms of the GNU Lesser General Public

  * License as published by the Free Software Foundation; either

  * version 2.1 of the License, or (at your option) any later version.

  *  

  * This library 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

  * Lesser General Public License for more details.

  * 

  * You should have received a copy of the GNU Lesser General Public

  * License along with this library; if not, write to the Free Software

  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

  */

 package org.jaudiotagger.audio.flac;

 import org.jaudiotagger.audio.exceptions.CannotReadException;

 import org.jaudiotagger.audio.exceptions.CannotWriteException;

 import org.jaudiotagger.audio.flac.metadatablock.*;

 import org.jaudiotagger.tag.Tag;

 import org.jaudiotagger.tag.flac.FlacTag;

 import java.io.IOException;

 import java.io.RandomAccessFile;

 import java.util.ArrayList;

 import java.util.List;

 import java.util.logging.Logger;

 /**

  * Write Flac Tag

  */

 public class FlacTagWriter

 {

     // Logger Object

     public static Logger logger = Logger.getLogger("org.jaudiotagger.audio.flac");

     private List<MetadataBlock> metadataBlockPadding = new ArrayList<MetadataBlock>(1);

     private List<MetadataBlock> metadataBlockApplication = new ArrayList<MetadataBlock>(1);

     private List<MetadataBlock> metadataBlockSeekTable = new ArrayList<MetadataBlock>(1);

     private List<MetadataBlock> metadataBlockCueSheet = new ArrayList<MetadataBlock>(1);

     private FlacTagCreator tc = new FlacTagCreator();

     private FlacTagReader reader = new FlacTagReader();

     /**

      * Delete Tag from file

      *

      * @param raf

      * @param tempRaf

      * @throws IOException

      * @throws CannotWriteException

      */

     public void delete(RandomAccessFile raf, RandomAccessFile tempRaf) throws IOException, CannotWriteException

     {

         //This will save the file without any Comment or PictureData blocks  

         FlacTag emptyTag = new FlacTag(null, new ArrayList<MetadataBlockDataPicture>());

         raf.seek(0);

         tempRaf.seek(0);

         write(emptyTag, raf, tempRaf);

     }

     /**

      * Write tag to file

      *

      * @param tag

      * @param raf

      * @param rafTemp

      * @throws CannotWriteException

      * @throws IOException

      */

     public void write(Tag tag, RandomAccessFile raf, RandomAccessFile rafTemp) throws CannotWriteException, IOException

     {

         logger.info("Writing tag");

         //Clean up old data

         metadataBlockPadding.clear();

         metadataBlockApplication.clear();

         metadataBlockSeekTable.clear();

         metadataBlockCueSheet.clear();

         //Read existing data

         FlacStreamReader flacStream = new FlacStreamReader(raf);

         try

         {

             flacStream.findStream();

         }

         catch (CannotReadException cre)

         {

             throw new CannotWriteException(cre.getMessage());

         }

         boolean isLastBlock = false;

         while (!isLastBlock)

         {

             MetadataBlockHeader mbh = MetadataBlockHeader.readHeader(raf);

             switch (mbh.getBlockType())

             {

                 case VORBIS_COMMENT:

                 case PADDING:

                 case PICTURE:

                 {

                     //All these will be replaced by the new metadata so we just treat as padding in order

                     //to determine how much space is already allocated in the file

                     raf.seek(raf.getFilePointer() + mbh.getDataLength());

                     MetadataBlockData mbd = new MetadataBlockDataPadding(mbh.getDataLength());

                     metadataBlockPadding.add(new MetadataBlock(mbh, mbd));

                     break;

                 }

                 case APPLICATION:

                 {

                     MetadataBlockData mbd = new MetadataBlockDataApplication(mbh, raf);

                     metadataBlockApplication.add(new MetadataBlock(mbh, mbd));

                     break;

                 }

                 case SEEKTABLE:

                 {

                     MetadataBlockData mbd = new MetadataBlockDataSeekTable(mbh, raf);

                     metadataBlockSeekTable.add(new MetadataBlock(mbh, mbd));

                     break;

                 }

                 case CUESHEET:

                 {

                     MetadataBlockData mbd = new MetadataBlockDataCueSheet(mbh, raf);

                     metadataBlockCueSheet.add(new MetadataBlock(mbh, mbd));

                     break;

                 }

                 default:

                 {

                     //What are the consequences of doing this

                     raf.seek(raf.getFilePointer() + mbh.getDataLength());

                     break;

                 }

             }

             isLastBlock = mbh.isLastBlock();

         }

         //Number of bytes in the existing file available before audio data

         int availableRoom = computeAvailableRoom();

         //Minimum Size of the New tag data without padding         

         int newTagSize = tc.convert(tag).limit();

         //Number of bytes required for new tagdata and other metadata blocks

         int neededRoom = newTagSize + computeNeededRoom();

         //Go to start of Flac within file

         raf.seek(flacStream.getStartOfFlacInFile());

         logger.info("Writing tag available bytes:" + availableRoom + ":needed bytes:" + neededRoom);

         //There is enough room to fit the tag without moving the audio just need to

         //adjust padding accordingly need to allow space for padding header if padding required

         if ((availableRoom == neededRoom) || (availableRoom > neededRoom + MetadataBlockHeader.HEADER_LENGTH))

         {

             //Jump over Id3 (if exists) Flac and StreamInfoBlock

             raf.seek(flacStream.getStartOfFlacInFile() + FlacStreamReader.FLAC_STREAM_IDENTIFIER_LENGTH + MetadataBlockHeader.HEADER_LENGTH + MetadataBlockDataStreamInfo.STREAM_INFO_DATA_LENGTH);

             //Write Application Blocks

             for (MetadataBlock aMetadataBlockApplication : metadataBlockApplication)

             {

                 raf.write(aMetadataBlockApplication.getHeader().getBytesWithoutIsLastBlockFlag());

                 raf.write(aMetadataBlockApplication.getData().getBytes());

             }

             //Write Seek Table Blocks

             for (MetadataBlock aMetadataBlockSeekTable : metadataBlockSeekTable)

             {

                 raf.write(aMetadataBlockSeekTable.getHeader().getBytesWithoutIsLastBlockFlag());

                 raf.write(aMetadataBlockSeekTable.getData().getBytes());

             }

             //Write Cue sheet Blocks

             for (MetadataBlock aMetadataBlockCueSheet : metadataBlockCueSheet)

             {

                 raf.write(aMetadataBlockCueSheet.getHeader().getBytesWithoutIsLastBlockFlag());

                 raf.write(aMetadataBlockCueSheet.getData().getBytes());

             }

             //Write tag (and padding)

             raf.getChannel().write(tc.convert(tag, availableRoom - neededRoom));

         }

         //Need to move audio

         else

         {

             //Skip to start of Audio

             //Write FlacStreamReader and StreamIfoMetablock to new file

             int dataStartSize = flacStream.getStartOfFlacInFile() + FlacStreamReader.FLAC_STREAM_IDENTIFIER_LENGTH + MetadataBlockHeader.HEADER_LENGTH + MetadataBlockDataStreamInfo.STREAM_INFO_DATA_LENGTH;

             raf.seek(0);

             rafTemp.getChannel().transferFrom(raf.getChannel(), 0, dataStartSize);

             rafTemp.seek(dataStartSize);

             //Write all the metadatablocks

             for (MetadataBlock aMetadataBlockApplication : metadataBlockApplication)

             {

                 rafTemp.write(aMetadataBlockApplication.getHeader().getBytesWithoutIsLastBlockFlag());

                 rafTemp.write(aMetadataBlockApplication.getData().getBytes());

             }

             for (MetadataBlock aMetadataBlockSeekTable : metadataBlockSeekTable)

             {

                 rafTemp.write(aMetadataBlockSeekTable.getHeader().getBytesWithoutIsLastBlockFlag());

                 rafTemp.write(aMetadataBlockSeekTable.getData().getBytes());

             }

             for (MetadataBlock aMetadataBlockCueSheet : metadataBlockCueSheet)

             {

                 rafTemp.write(aMetadataBlockCueSheet.getHeader().getBytesWithoutIsLastBlockFlag());

                 rafTemp.write(aMetadataBlockCueSheet.getData().getBytes());

             }

             //Write tag data use default padding

             rafTemp.write(tc.convert(tag, FlacTagCreator.DEFAULT_PADDING).array());

             //Write audio to new file

             raf.seek(dataStartSize + availableRoom);

             rafTemp.getChannel().transferFrom(raf.getChannel(), rafTemp.getChannel().position(), raf.getChannel().size());

         }

     }

     /**

      * @return space currently availble for writing all Flac metadatablocks exceprt for StreamInfo which is fixed size

      */

     private int computeAvailableRoom()

     {

         int length = 0;

         for (MetadataBlock aMetadataBlockApplication : metadataBlockApplication)

         {

             length += aMetadataBlockApplication.getLength();

         }

         for (MetadataBlock aMetadataBlockSeekTable : metadataBlockSeekTable)

         {

             length += aMetadataBlockSeekTable.getLength();

         }

         for (MetadataBlock aMetadataBlockCueSheet : metadataBlockCueSheet)

         {

             length += aMetadataBlockCueSheet.getLength();

         }

         for (MetadataBlock aMetadataBlockPadding : metadataBlockPadding)

         {

             length += aMetadataBlockPadding.getLength();

         }

         return length;

     }

     /**

      * @return space required to write the metadata blocks that are part of Flac but are not part of tagdata

      *         in the normal sense.

      */

     private int computeNeededRoom()

     {

         int length = 0;

         for (MetadataBlock aMetadataBlockApplication : metadataBlockApplication)

         {

             length += aMetadataBlockApplication.getLength();

         }

         for (MetadataBlock aMetadataBlockSeekTable : metadataBlockSeekTable)

         {

             length += aMetadataBlockSeekTable.getLength();

         }

         for (MetadataBlock aMetadataBlockCueSheet : metadataBlockCueSheet)

         {

             length += aMetadataBlockCueSheet.getLength();

         }

         return length;

     }

 }