/*

  * jaudiotagger library

  *

  * 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.generic;

 import org.jaudiotagger.tag.*;

 import org.jaudiotagger.tag.datatype.Artwork;

 import org.jaudiotagger.tag.mp4.Mp4TagField;

 import org.jaudiotagger.tag.mp4.Mp4FieldKey;

 import java.util.*;

 /**

  * This class is the default implementation for

  * {@link org.jaudiotagger.tag.Tag} and introduces some more useful

  * functionality to be implemented.<br>

  *

  * @author Rapha�l Slinckx

  */

 public abstract class AbstractTag implements Tag

 {

     /**

      * Stores the amount of {@link TagField} with {@link TagField#isCommon()}

      * <code>true</code>.

      */

     protected int commonNumber = 0;

     /**

      * This map stores the {@linkplain TagField#getId() ids} of the stored

      * fields to the {@linkplain TagField fields} themselves. Because a linked hashMap is used the order

      * that they are added in is preserved, the only exception to this rule is when two fields of the same id

      * exist, both will be returned according to when the first item was added to the file. <br>

      */

     protected Map<String, List<TagField>> fields = new LinkedHashMap<String, List<TagField>>();

     /**

      * Add field

      *

      * @see org.jaudiotagger.tag.Tag#add(org.jaudiotagger.tag.TagField)

      *      <p/>

      *      Changed so add empty fields

      */

     public void add(TagField field)

     {

         if (field == null)

         {

             return;

         }

         List<TagField> list = fields.get(field.getId());

         // There was no previous item

         if (list == null)

         {

             list = new ArrayList<TagField>();

             list.add(field);

             fields.put(field.getId(), list);

             if (field.isCommon())

             {

                 commonNumber++;

             }

         }

         else

         {

             // We append to existing list

             list.add(field);

         }

     }

     /**

      * Add (another) album

      *

      * @see org.jaudiotagger.tag.Tag#addAlbum(java.lang.String)

      */

     public void addAlbum(String s)

     {

         add(createAlbumField(s));

     }

     /**

      * Add (another) artist

      *

      * @see org.jaudiotagger.tag.Tag#addArtist(java.lang.String)

      */

     public void addArtist(String s)

     {

         add(createArtistField(s));

     }

     /**

      * Add (another) comment

      *

      * @see org.jaudiotagger.tag.Tag#addComment(java.lang.String)

      */

     public void addComment(String s)

     {

         add(createCommentField(s));

     }

     /**

      * Add (another) genre

      *

      * @see org.jaudiotagger.tag.Tag#addGenre(java.lang.String)

      */

     public void addGenre(String s)

     {

         add(createGenreField(s));

     }

     /**

      * Add (another) title

      *

      * @see org.jaudiotagger.tag.Tag#addTitle(java.lang.String)

      */

     public void addTitle(String s)

     {

         add(createTitleField(s));

     }

     /**

      * Add (another) track

      *

      * @see org.jaudiotagger.tag.Tag#addTrack(java.lang.String)

      */

     public void addTrack(String s) throws FieldDataInvalidException

     {

         add(createTrackField(s));

     }

     /**

      * (Add (another) year

      *

      * @see org.jaudiotagger.tag.Tag#addYear(java.lang.String)

      */

     public void addYear(String s)

     {

         add(createYearField(s));

     }

     /**

      * Get list of fields within this tag with the specified id

      *

      * @see org.jaudiotagger.tag.Tag#get(java.lang.String)

      */

     public List<TagField> get(String id)

     {

         List<TagField> list = fields.get(id);

         if (list == null)

         {

             return new ArrayList<TagField>();

         }

         return list;

     }

     /**

      * @param id

      * @return

      */

     //Needs to be overridden

     //TODO remove

     public List<TagField> get(TagFieldKey id) throws KeyNotFoundException

     {

         List<TagField> list = fields.get(id.name());

         if (list == null)

         {

             return new ArrayList<TagField>();

         }

         return list;

     }

     /**

      * @param id

      * @return matches for this saudio-specific key

      */

     public String getFirst(String id)

     {

         List<TagField> l = get(id);

         return (l.size() != 0) ? l.get(0).toString() : "";

     }

     public TagField getFirstField(String id)

     {

         List<TagField> l = get(id);

         return (l.size() != 0) ? l.get(0) : null;

     }

     /**

      * (overridden)

      *

      * @see org.jaudiotagger.tag.Tag#getAlbum()

      */

     public List<TagField> getAlbum()

     {

         return get(getAlbumId());

     }

     /**

      * Returns the identifier for a field representing the &quot;album&quot;<br>

      *

      * @return identifier for the "album" field.

      * @see TagField#getId()

      */

     protected abstract String getAlbumId();

     /**

      * Get Artist

      *

      * @see org.jaudiotagger.tag.Tag#getArtist()

      */

     public List<TagField> getArtist()

     {

         return get(getArtistId());

     }

     /**

      * Returns the identifier for a field representing the &quot;artist&quot;<br>

      *

      * @return identifier for the "artist" field.

      * @see TagField#getId()

      */

     protected abstract String getArtistId();

     /**

      * Get Comment

      *

      * @see org.jaudiotagger.tag.Tag#getComment()

      */

     public List<TagField> getComment()

     {

         return get(getCommentId());

     }

     /**

      * Returns the identifier for a field representing the &quot;comment&quot;<br>

      *

      * @return identifier for the "comment" field.

      * @see TagField#getId()

      */

     protected abstract String getCommentId();

     /**

      * @see org.jaudiotagger.tag.Tag#getFields()

      */

     public Iterator<TagField> getFields()

     {

         final Iterator<Map.Entry<String, List<TagField>>> it = this.fields.entrySet().iterator();

         return new Iterator<TagField>()

         {

             private Iterator<TagField> fieldsIt;

             private void changeIt()

             {

                 if (!it.hasNext())

                 {

                     return;

                 }

                 Map.Entry<String, List<TagField>> e = it.next();

                 List<TagField> l = e.getValue();

                 fieldsIt = l.iterator();

             }

             public boolean hasNext()

             {

                 if (fieldsIt == null)

                 {

                     changeIt();

                 }

                 return it.hasNext() || (fieldsIt != null && fieldsIt.hasNext());

             }

             public TagField next()

             {

                 if (!fieldsIt.hasNext())

                 {

                     changeIt();

                 }

                 return fieldsIt.next();

             }

             public void remove()

             {

                 fieldsIt.remove();

             }

         };

     }

     /**

      * Return field count

      * <p/>

      * TODO:There must be a more efficient way to do this.

      *

      * @return field count

      */

     public int getFieldCount()

     {

         Iterator it = getFields();

         int count = 0;

         while (it.hasNext())

         {

             count++;

             it.next();

         }

         return count;

     }

     /**

      * Get the first album or empty string if doesnt exist

      *

      * @see org.jaudiotagger.tag.Tag#getFirstAlbum()

      */

     public String getFirstAlbum()

     {

         List<TagField> l = getAlbum();

         return (l.size() != 0) ? ((TagTextField) l.get(0)).getContent() : "";

     }

     /**

      * Get the first artist or empty string if doesnt exist

      *

      * @see org.jaudiotagger.tag.Tag#getFirstArtist()

      */

     public String getFirstArtist()

     {

         List<TagField> l = getArtist();

         return (l.size() != 0) ? ((TagTextField) l.get(0)).getContent() : "";

     }

     /**

      * Get the first comment or empty string if doesnt exist

      *

      * @see org.jaudiotagger.tag.Tag#getFirstComment()

      */

     public String getFirstComment()

     {

         List<TagField> l = getComment();

         return (l.size() != 0) ? ((TagTextField) l.get(0)).getContent() : "";

     }

     /**

      * Get the first genre or empty string if doesnt exist

      *

      * @see org.jaudiotagger.tag.Tag#getFirstGenre()

      */

     public String getFirstGenre()

     {

         List<TagField> l = getGenre();

         return (l.size() != 0) ? ((TagTextField) l.get(0)).getContent() : "";

     }

     /**

      * Get the first title or empty string if doesnt exist

      *

      * @see org.jaudiotagger.tag.Tag#getFirstTitle()

      */

     public String getFirstTitle()

     {

         List<TagField> l = getTitle();

         return (l.size() != 0) ? ((TagTextField) l.get(0)).getContent() : "";

     }

     /**

      * Get the first track or empty string if doesnt exist

      *

      * @see org.jaudiotagger.tag.Tag#getFirstTrack()

      */

     public String getFirstTrack()

     {

         List<TagField> l = getTrack();

         return (l.size() != 0) ? ((TagTextField) l.get(0)).getContent() : "";

     }

     /**

      * Get the first year or empty string if doesnt exist

      *

      * @see org.jaudiotagger.tag.Tag#getFirstYear()

      */

     public String getFirstYear()

     {

         List<TagField> l = getYear();

         return (l.size() != 0) ? ((TagTextField) l.get(0)).getContent() : "";

     }

     /**

      * Get the genres or empty list if none exist

      *

      * @see org.jaudiotagger.tag.Tag#getGenre()

      */

     public List<TagField> getGenre()

     {

         return get(getGenreId());

     }

     /**

      * Returns the identifier for a field representing the &quot;genre&quot;<br>

      *

      * @return identifier for the "genre" field.

      * @see TagField#getId()

      */

     protected abstract String getGenreId();

     /**

      * Get the titles or empty list if none exist

      *

      * @see org.jaudiotagger.tag.Tag#getTitle()

      */

     public List<TagField> getTitle()

     {

         return get(getTitleId());

     }

     /**

      * Returns the identifier for a field representing the &quot;title&quot;<br>

      *

      * @return identifier for the "title" field.

      * @see TagField#getId()

      */

     protected abstract String getTitleId();

     /**

      * Get the tracks or empty list if none exist

      *

      * @see org.jaudiotagger.tag.Tag#getTrack()

      */

     public List<TagField> getTrack()

     {

         return get(getTrackId());

     }

     /**

      * Returns the identifier for a field representing the &quot;track&quot;<br>

      *

      * @return identifier for the "track" field.

      * @see TagField#getId()

      */

     protected abstract String getTrackId();

     /**

      * Get the  years or empty list if none exist

      *

      * @see org.jaudiotagger.tag.Tag#getYear()

      */

     public List<TagField> getYear()

     {

         return get(getYearId());

     }

     /**

      * Returns the identifier for a field representing the &quot;year&quot;<br>

      *

      * @return identifier for the "year" field.

      * @see TagField#getId()

      */

     protected abstract String getYearId();

     /**

      * Does this tag contain any comon fields

      *

      * @see org.jaudiotagger.tag.Tag#hasCommonFields()

      */

     public boolean hasCommonFields()

     {

         return commonNumber != 0;

     }

     /**

      * Does this tag contain a field with the specified id

      *

      * @see org.jaudiotagger.tag.Tag#hasField(java.lang.String)

      */

     public boolean hasField(String id)

     {

         return get(id).size() != 0;

     }

     /**

      * Determines whether the given charset encoding may be used for the

      * represented tagging system.

      *

      * @param enc charset encoding.

      * @return <code>true</code> if the given encoding can be used.

      */

     protected abstract boolean isAllowedEncoding(String enc);

     /**

      * Is this tag empty

      *

      * @see org.jaudiotagger.tag.Tag#isEmpty()

      */

     public boolean isEmpty()

     {

         return fields.size() == 0;

     }

     /**

      * Set field

      * <p/>

      * Changed:Just because field is empty it doesnt mean it should be deleted. That should be the choice

      * of the developer. (Or does this break things)

      *

      * @see org.jaudiotagger.tag.Tag#set(org.jaudiotagger.tag.TagField)

      */

     public void set(TagField field)

     {

         if (field == null)

         {

             return;

         }

         // If there is already an existing field with same id

         // and both are TextFields, we replace the first element

         List<TagField> list = fields.get(field.getId());

         if (list != null)

         {

             list.set(0, field);

             return;

         }

         // Else we put the new field in the fields.

         list = new ArrayList<TagField>();

         list.add(field);

         fields.put(field.getId(), list);

         if (field.isCommon())

         {

             commonNumber++;

         }

     }

     /**

      * Set or add album

      *

      * @see org.jaudiotagger.tag.Tag#setAlbum(java.lang.String)

      */

     public void setAlbum(String s)

     {

         set(createAlbumField(s));

     }

     /**

      * Set or add artist

      *

      * @see org.jaudiotagger.tag.Tag#setArtist(java.lang.String)

      */

     public void setArtist(String s)

     {

         set(createArtistField(s));

     }

     /**

      * Set or add comment

      *

      * @see org.jaudiotagger.tag.Tag#setComment(java.lang.String)

      */

     public void setComment(String s)

     {

         set(createCommentField(s));

     }

     /**

      * Set or add encoding

      *

      * @see org.jaudiotagger.tag.Tag#setEncoding(java.lang.String)

      */

     public boolean setEncoding(String enc)

     {

         if (!isAllowedEncoding(enc))

         {

             return false;

         }

         Iterator it = getFields();

         while (it.hasNext())

         {

             TagField field = (TagField) it.next();

             if (field instanceof TagTextField)

             {

                 ((TagTextField) field).setEncoding(enc);

             }

         }

         return true;

     }

     /**

      * Set or add genre

      *

      * @see org.jaudiotagger.tag.Tag#setGenre(java.lang.String)

      */

     public void setGenre(String s)

     {

         set(createGenreField(s));

     }

     /**

      * Set or add title

      *

      * @see org.jaudiotagger.tag.Tag#setTitle(java.lang.String)

      */

     public void setTitle(String s)

     {

         set(createTitleField(s));

     }

     /**

      * Set or add track

      *

      * @see org.jaudiotagger.tag.Tag#setTrack(java.lang.String)

      */

     public void setTrack(String s) throws FieldDataInvalidException

     {

         set(createTrackField(s));

     }

     /**

      * Set or add year

      *

      * @see org.jaudiotagger.tag.Tag#setYear(java.lang.String)

      */

     public void setYear(String s)

     {

         set(createYearField(s));

     }

     /**

      * (overridden)

      *

      * @see java.lang.Object#toString()

      */

     public String toString()

     {

         StringBuffer out = new StringBuffer();

         out.append("Tag content:\n");

         Iterator it = getFields();

         while (it.hasNext())

         {

             TagField field = (TagField) it.next();

             out.append("\t");

             out.append(field.getId());

             out.append(":");

             out.append(field.toString());

             out.append("\n");

         }

         return out.toString().substring(0, out.length() - 1);

     }

     /**

      *

      * @param genericKey

      * @param value

      * @return

      * @throws KeyNotFoundException

      * @throws FieldDataInvalidException

      */

     public abstract TagField createTagField(TagFieldKey genericKey, String value) throws KeyNotFoundException, FieldDataInvalidException;

     /**

      *

      * @param genericKey

      * @return

      * @throws KeyNotFoundException

      */

     public abstract String getFirst(TagFieldKey genericKey) throws KeyNotFoundException;

     /**

      * 

      * @param genericKey

      * @return

      * @throws KeyNotFoundException

      */

     public abstract TagField getFirstField(TagFieldKey genericKey) throws KeyNotFoundException;

     /**

      * 

      * @param tagFieldKey

      * @throws KeyNotFoundException

      */

     public abstract void deleteTagField(TagFieldKey tagFieldKey) throws KeyNotFoundException;

     /**

      * Delete all ocurrences of field.

      *

      * @param key

      */

     protected void deleteField(String key)

     {

         Object removed = fields.remove(key);

         //if (removed != null && field.isCommon())

         //    commonNumber--;

         return;

     }

     /**

      * Creates a field which represents the &quot;album&quot;.<br>

      * The field will already contain the given content.

      *

      * @param content The content of the created field.

      * @return tagfield representing the "album"

      */

     public abstract TagField createAlbumField(String content);

     /**

      * Creates a field which represents the &quot;artist&quot;.<br>

      * The field will already contain the given content.

      *

      * @param content The content of the created field.

      * @return tagfield representing the "artist"

      */

     public abstract TagField createArtistField(String content);

     /**

      * Creates a field which represents the &quot;comment&quot;.<br>

      * The field will already contain the given content.

      *

      * @param content The content of the created field.

      * @return tagfield representing the "comment"

      */

     public abstract TagField createCommentField(String content);

     /**

      * Creates a field which represents the &quot;genre&quot;.<br>

      * The field will already contain the given content.

      *

      * @param content The content of the created field.

      * @return tagfield representing the "genre"

      */

     public abstract TagField createGenreField(String content);

     /**

      * Creates a field which represents the &quot;title&quot;.<br>

      * The field will already contain the given content.

      *

      * @param content The content of the created field.

      * @return tagfield representing the "title"

      */

     public abstract TagField createTitleField(String content);

     /**

      * Creates a field which represents the &quot;track&quot;.<br>

      * The field will already contain the given content.

      *

      * @param content The content of the created field.

      * @return tagfield representing the "track"

      */

     public abstract TagField createTrackField(String content) throws FieldDataInvalidException;

     /**

      * Creates a field which represents the &quot;year&quot;.<br>

      * The field will already contain the given content.

      *

      * @param content The content of the created field.

      * @return tagfield representing the "year"

      */

     public abstract TagField createYearField(String content);

     public Artwork getFirstArtwork()

     {

         List<Artwork> artwork = getArtworkList();

         if(artwork.size()>0)

         {

             return artwork.get(0);

         }

         return null;

     }

       /**

      * Create field and then set within tag itself

      *

      * @param artwork

      * @throws FieldDataInvalidException

      */

     public void createAndSetArtworkField(Artwork artwork) throws FieldDataInvalidException

     {

         this.set(createArtworkField(artwork));

     }

 }