/*

  * 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.tag.mp4.field;

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

 import org.jaudiotagger.tag.TagField;

 import org.jaudiotagger.tag.TagTextField;

 import org.jaudiotagger.tag.mp4.Mp4TagField;

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

 import java.io.UnsupportedEncodingException;

 import java.nio.ByteBuffer;

 /**

  * Represents a single text field

  * <p/>

  * <p>Mp4 metadata normally held as follows:

  * <pre>

  * MP4Box Parent contains

  *      :length (includes length of data child)  (4 bytes)

  *      :name         (4 bytes)

  *      :child with

  *          :length          (4 bytes)

  *          :name 'Data'     (4 bytes)

  *          :atom version    (1 byte)

  *          :atom type flags (3 bytes)

  *          :null field      (4 bytes)

  *          :data

  * </pre>

  * <p/>

  * <p>Note:This class is initilized with the child data atom only, the parent data has already been processed, this may

  * change as it seems that code should probably be enscapulated into this. Whereas the raw content returned by the

  * getRawContent() contais the byte data for parent and child.

  */

 public class Mp4TagTextField extends Mp4TagField implements TagTextField

 {

     protected int dataSize;

     protected String content;

     /**

      * Construct from File

      *

      * @param id   parent id

      * @param data atom data

      * @throws UnsupportedEncodingException

      */

     public Mp4TagTextField(String id, ByteBuffer data) throws UnsupportedEncodingException

     {

         super(id, data);

     }

     /**

      * Construct new Field

      *

      * @param id      parent id

      * @param content data atom data

      */

     public Mp4TagTextField(String id, String content)

     {

         super(id);

         this.content = content;

     }

     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();

         content = databox.getContent();

     }

     public void copyContent(TagField field)

     {

         if (field instanceof Mp4TagTextField)

         {

             this.content = ((Mp4TagTextField) field).getContent();

         }

     }

     public String getContent()

     {

         return content;

     }

     protected byte[] getDataBytes() throws UnsupportedEncodingException

     {

         return content.getBytes(getEncoding());

     }

     public Mp4FieldType getFieldType()

     {

         return Mp4FieldType.TEXT;

     }

     public String getEncoding()

     {

         return Mp4BoxHeader.CHARSET_UTF_8;

     }

     public boolean isBinary()

     {

         return false;

     }

     public boolean isEmpty()

     {

         return this.content.trim().equals("");

     }

     public void setContent(String s)

     {

         this.content = s;

     }

     public void setEncoding(String s)

     {

         /* Not allowed */

     }

     public String toString()

     {

         return content;

     }

 }