/*
 *  MusicTag Copyright (C)2003,2004
 *
 *  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,
 *  you can get a copy from http://www.opensource.org/licenses/lgpl-license.php or write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */
package org.jaudiotagger.tag.id3.framebody;

import org.jaudiotagger.tag.InvalidTagException;
import org.jaudiotagger.tag.datatype.DataTypes;
import org.jaudiotagger.tag.datatype.NumberHashMap;
import org.jaudiotagger.tag.datatype.Pair;
import org.jaudiotagger.tag.datatype.PairedTextEncodedStringNullTerminated;
import org.jaudiotagger.tag.id3.ID3v23Frames;
import org.jaudiotagger.tag.id3.valuepair.TextEncoding;

import java.io.ByteArrayOutputStream;
import java.nio.ByteBuffer;
import java.util.Map;
import java.util.StringTokenizer;

/**
 * Involved People List ID3v22/v23 Only
 * <p/>
 * Since there might be a lot of people contributing to an audio file in various ways, such as musicians and technicians,
 * the 'Text information frames' are often insufficient to list everyone involved in a project.
 * The 'Involved people list' is a frame containing the names of those involved, and how they were involved.
 * The body simply contains a terminated string with the involvement directly followed by a terminated string with
 * the involvee followed by a new involvement and so on. There may only be one "IPLS" frame in each tag.
 * <p/>
 * <Header for 'Involved people list', ID: "IPLS">
 * Text encoding	$xx
 * People list strings	<text strings according to encoding>
 * <p/>
 * <p>For more details, please refer to the ID3 specifications:
 * <ul>
 * <li><a href="http://www.id3.org/id3v2.3.0.txt">ID3 v2.3.0 Spec</a>
 * </ul>
 *
 * @author : Paul Taylor
 * @author : Eric Farng
 * @version $Id: FrameBodyIPLS.java 923 2010-10-16 21:59:49Z paultaylor $
 */
public class FrameBodyIPLS extends AbstractID3v2FrameBody implements ID3v23FrameBody
{
    /**
     * Creates a new FrameBodyIPLS datatype.
     */
    public FrameBodyIPLS()
    {
        super();
        setObjectValue(DataTypes.OBJ_TEXT_ENCODING, TextEncoding.ISO_8859_1);
    }

    public FrameBodyIPLS(ByteBuffer byteBuffer, int frameSize) throws InvalidTagException
    {
        super(byteBuffer, frameSize);
    }

    /**
     * The ID3v23 frame identifier
     *
     * @return the ID3v23 frame identifier for this frame type
     */
    public String getIdentifier()
    {
        return ID3v23Frames.FRAME_ID_V3_IPLS;
    }

    public FrameBodyIPLS(FrameBodyIPLS body)
    {
        super(body);
    }

    /**
     * Creates a new FrameBodyIPLS data type.
     *
     * @param textEncoding
     * @param text
     */
    public FrameBodyIPLS(byte textEncoding, String text)
    {
        setObjectValue(DataTypes.OBJ_TEXT_ENCODING, textEncoding);
        setText(text);
    }

    /**
     * Convert from V4 to V3 Frame
     * @param body
     */
    public FrameBodyIPLS(FrameBodyTIPL body)
    {
        setObjectValue(DataTypes.OBJ_TEXT_ENCODING, body.getTextEncoding());
        setText(body.getText());
    }

    /**
     * Set the text, decoded as pairs of involvee - involvement
     * @param text
     */
    public void setText(String text)
    {
        PairedTextEncodedStringNullTerminated.ValuePairs value = new PairedTextEncodedStringNullTerminated.ValuePairs();
        StringTokenizer stz = new StringTokenizer(text, "\0");
        while (stz.hasMoreTokens())
        {
            String key =stz.nextToken();
            if(stz.hasMoreTokens())
            {
                value.add(key, stz.nextToken());
            }

        }
        setObjectValue(DataTypes.OBJ_TEXT, value);
    }

    public void addPair(String text)
    {
        PairedTextEncodedStringNullTerminated.ValuePairs value = ((PairedTextEncodedStringNullTerminated) getObject(DataTypes.OBJ_TEXT)).getValue();
        StringTokenizer stz = new StringTokenizer(text, "\0");
        if (stz.hasMoreTokens())
        {
            value.add(stz.nextToken(),stz.nextToken());
        }
    }

    /**
     * Because have a text encoding we need to check the data values do not contain characters that cannot be encoded in
     * current encoding before we write data. If they do change the encoding.
     */
    public void write(ByteArrayOutputStream tagBuffer)
    {
        if (!((PairedTextEncodedStringNullTerminated) getObject(DataTypes.OBJ_TEXT)).canBeEncoded())
        {
            this.setTextEncoding(TextEncoding.UTF_16);
        }
        super.write(tagBuffer);
    }

    /**
     * Consists of a text encoding , and then a series of null terminated Strings, there should be an even number
     * of Strings as they are paired as involvement/involvee
     */
    protected void setupObjectList()
    {
        objectList.add(new NumberHashMap(DataTypes.OBJ_TEXT_ENCODING, this, TextEncoding.TEXT_ENCODING_FIELD_SIZE));
        objectList.add(new PairedTextEncodedStringNullTerminated(DataTypes.OBJ_TEXT, this));
    }

    public PairedTextEncodedStringNullTerminated.ValuePairs getPairing()
    {
        return  (PairedTextEncodedStringNullTerminated.ValuePairs)getObject(DataTypes.OBJ_TEXT).getValue();  
    }
     /**
     * Get key at index
     *
     * @param index
     * @return value at index
     */
    public String getKeyAtIndex(int index)
    {
        PairedTextEncodedStringNullTerminated text = (PairedTextEncodedStringNullTerminated) getObject(DataTypes.OBJ_TEXT);
        return text.getValue().getMapping().get(index).getKey();
    }

     /**
     * Get value at index
     *
     * @param index
     * @return value at index
     */
    public String getValueAtIndex(int index)
    {
        PairedTextEncodedStringNullTerminated text = (PairedTextEncodedStringNullTerminated) getObject(DataTypes.OBJ_TEXT);
        return text.getValue().getMapping().get(index).getValue();
    }

    /**
     * @return number of text pairs
     */
    public int getNumberOfPairs()
    {
        PairedTextEncodedStringNullTerminated text = (PairedTextEncodedStringNullTerminated) getObject(DataTypes.OBJ_TEXT);
        return text.getValue().getNumberOfPairs();
    }

    public String getText()
    {
        PairedTextEncodedStringNullTerminated text = (PairedTextEncodedStringNullTerminated) getObject(DataTypes.OBJ_TEXT);
        StringBuilder sb = new StringBuilder();
        int count=1;
        for(Pair entry:text.getValue().getMapping())
        {
            sb.append(entry.getKey()+'\0'+entry.getValue());
            if(count!=getNumberOfPairs())
            {
                sb.append('\0');
            }
            count++;
        }
        return sb.toString();
    }

     public String getUserFriendlyValue()
    {
        return getText();
    }
}