package org.jaudiotagger.tag.mp4.field;

 import org.jaudiotagger.audio.mp4.atom.Mp4BoxHeader;

 import org.jaudiotagger.logging.ErrorMessage;

 import org.jaudiotagger.tag.mp4.Mp4FieldKey;

 import org.jaudiotagger.tag.mp4.atom.Mp4DataBox;

 import org.jaudiotagger.tag.reference.GenreTypes;

 import java.io.UnsupportedEncodingException;

 import java.nio.ByteBuffer;

 import java.util.ArrayList;

 /**

  * Represents the Genre field , when user has selected from the set list of genres

  * <p/>

  * <p>This class allows you to retrieve either the internal genreid, or the display value

  */

 public class Mp4GenreField extends Mp4TagTextNumberField

 {

     public Mp4GenreField(String id, ByteBuffer data) throws UnsupportedEncodingException

     {

         super(id, data);

     }

     /**

      * Precheck to see if the value is a valid genre or whether you should use a custom genre.

      *

      * @param genreId

      * @return

      */

     public static boolean isValidGenre(String genreId)

     {

         //Is it an id (within old id3 range)      

         try

         {

             short genreVal = Short.parseShort(genreId);

             if ((genreVal - 1) <= GenreTypes.getMaxStandardGenreId())

             {

                 return true;

             }

         }

         catch (NumberFormatException nfe)

         {

             //Do Nothing test as String instead

         }

         //Is it the String value ?

         Integer id3GenreId = GenreTypes.getInstanceOf().getIdForValue(genreId);

         if (id3GenreId != null)

         {

             if (id3GenreId <= GenreTypes.getMaxStandardGenreId())

             {

                 return true;

             }

         }

         return false;

     }

     /**

      * Construct genre, if cant find match just default to first genre

      *

      * @param genreId key into ID3v1 list (offset by one) or String value in ID3list

      */

     public Mp4GenreField(String genreId)

     {

         super(Mp4FieldKey.GENRE.getFieldName(), genreId);

         //Is it an id

         try

         {

             short genreVal = Short.parseShort(genreId);

             if ((genreVal - 1) <= GenreTypes.getMaxStandardGenreId())

             {

                 numbers = new ArrayList<Short>();

                 numbers.add(genreVal);

                 return;

             }

             //Default

             numbers = new ArrayList<Short>();

             numbers.add((short) (1));

             return;

         }

         catch (NumberFormatException nfe)

         {

             //Do Nothing test as String instead

         }

         //Is it the String value ?

         Integer id3GenreId = GenreTypes.getInstanceOf().getIdForValue(genreId);

         if (id3GenreId != null)

         {

             if (id3GenreId.intValue() <= GenreTypes.getMaxStandardGenreId())

             {

                 numbers = new ArrayList<Short>();

                 numbers.add((short) (id3GenreId + 1));

                 return;

             }

         }

         numbers = new ArrayList<Short>();

         numbers.add((short) (1));

         return;

     }

     protected void build(ByteBuffer data) throws UnsupportedEncodingException

     {

         //Data actually contains a 'Data' Box so process data using this

         Mp4BoxHeader header = new Mp4BoxHeader(data);

         Mp4DataBox databox = new Mp4DataBox(header, data);

         dataSize = header.getDataLength();

         numbers = databox.getNumbers();

         int genreId = numbers.get(0);

         //Get value, we have to adjust index by one because iTunes labels from one instead of zero

         content = GenreTypes.getInstanceOf().getValueForId(genreId - 1);

         //Some apps set genre to invalid value, we dont disguise this by setting content to empty string we leave

         //as null so apps can handle if they wish, but we do display a warning to make them aware.

         if (content == null)

         {

             logger.warning(ErrorMessage.MP4_GENRE_OUT_OF_RANGE.getMsg(genreId));

         }

     }

 }